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#!/usr/bin/python2.4 # # Copyright 2010 Google Inc. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. """Http tests Unit tests for the apiclient.http. """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' import unittest from apiclient.http import set_user_agent from apiclient.http import HttpMockSequence class TestUserAgent(unittest.TestCase): def test_set_user_agent(self): http = HttpMockSequence([ ({'status': '200'}, 'echo_request_headers'), ]) http = set_user_agent(http, "my_app/5.5") resp, content = http.request("http://example.com") self.assertEqual(content['user-agent'], 'my_app/5.5') def test_set_user_agent_nested(self): http = HttpMockSequence([ ({'status': '200'}, 'echo_request_headers'), ]) http = set_user_agent(http, "my_app/5.5") http = set_user_agent(http, "my_library/0.1") resp, content = http.request("http://example.com") self.assertEqual(content['user-agent'], 'my_app/5.5 my_library/0.1') if __name__ == '__main__': unittest.main()
Python
#!/usr/bin/env python """Execute all sample applications. Runs over all the sample applications, determines their type (App Engine, Django, or a command-line application), and then runs them checking for a good return status in the case of command-line applications and a 200 OK response in the case of the App Engine and Django samples. """ import gflags import httplib2 import logging import os import signal import subprocess import sys import time FLAGS = gflags.FLAGS gflags.DEFINE_list('samples_to_skip', ['latitude'], 'A comma separated list of project directory names to be skipped.') gflags.DEFINE_enum('logging_level', 'INFO', ['DEBUG', 'INFO', 'WARNING', 'ERROR', 'CRITICAL'], 'Set the level of logging detail.') gflags.DEFINE_string('app_engine_dir', '../google_appengine/', 'Directory where Google App Engine is installed.') gflags.DEFINE_string('sample_root', 'samples/oauth2', 'The root directory for all the samples.') def main(argv): try: argv = FLAGS(argv) except gflags.FlagsError, e: print '%s\\nUsage: %s ARGS\\n%s' % (e, argv[0], FLAGS) sys.exit(1) logging.getLogger().setLevel(getattr(logging, FLAGS.logging_level)) for dirname in os.listdir(FLAGS.sample_root): if dirname in FLAGS.samples_to_skip: logging.debug('Skipping ' + fulldirname + ' (blacklist)') continue fulldirname = os.path.join(FLAGS.sample_root, dirname) filelist = os.listdir(fulldirname) if 'settings.py' in filelist and 'manage.py' in filelist: logging.info(fulldirname + ' [Django]') proc = subprocess.Popen( [os.path.join(fulldirname, 'manage.py'), 'runserver']) # Now just wait, because Django actually spawns a sub-process that does # the I/O and does something funky with stdout so we can't read it and # figure out when it is started. time.sleep(3) h = httplib2.Http() resp, content = h.request('http://localhost:8000/') assert(200 == resp.status) time.sleep(1) logging.debug('Django ppid: %d', proc.pid) # Find and kill the sub-process manage.py forked. findpids = subprocess.Popen(['ps', '--ppid', str(proc.pid), 'o', 'pid',], stdout=subprocess.PIPE) for p in findpids.stdout.readlines(): if 'PID' not in p: os.kill(int(p), signal.SIGINT) os.kill(proc.pid, signal.SIGINT) proc.wait() elif 'app.yaml' in filelist: logging.info(fulldirname + ' [App Engine]') proc = subprocess.Popen( [os.path.join(FLAGS.app_engine_dir, 'dev_appserver.py'), fulldirname], stdout=subprocess.PIPE, stderr=subprocess.STDOUT) line = proc.stdout.readline() logging.debug('READ: ' + line) while '] Running application' not in line: line = proc.stdout.readline() logging.debug('READ: ' + line) h = httplib2.Http() resp, content = h.request('http://localhost:8080/') assert(200 == resp.status) time.sleep(1) os.kill(proc.pid, signal.SIGINT) proc.wait() else: logging.info(fulldirname + ' [Command-line]') for filename in os.listdir(fulldirname): if filename.endswith('.py'): logging.info('Running: ' + filename) proc = subprocess.Popen(['python', os.path.join(fulldirname, filename)]) returncode = proc.wait() assert(returncode == 0) if __name__ == '__main__': main(sys.argv)
Python
#!/usr/bin/env python import glob import logging import os import sys import unittest from trace import fullmodname # Conditional import of cleanup function try: from tests.utils import cleanup except: def cleanup(): pass # Ensure current working directory is in path sys.path.insert(0, os.getcwd()) def build_suite(folder, verbosity): # find all of the test modules top_level_modules = map(fullmodname, glob.glob(os.path.join(folder, 'test_*.py'))) # TODO(ade) Verify that this works on Windows. If it doesn't then switch to os.walk instead lower_level_modules = map(fullmodname, glob.glob(os.path.join(folder, '*/test_*.py'))) modules = top_level_modules + lower_level_modules if verbosity > 0: print "Running the tests found in the following modules:" print modules # load all of the tests into a suite try: return unittest.TestLoader().loadTestsFromNames(modules) except Exception, exception: # attempt to produce a more specific message for module in modules: __import__(module) raise def run(test_folder_name, verbosity, exit_on_failure): # Build and run the tests in test_folder_name tests = build_suite(test_folder_name, verbosity) result = unittest.TextTestRunner(verbosity=verbosity).run(tests) if exit_on_failure and not result.wasSuccessful(): sys.exit(1) cleanup() def main(): if '--help' in sys.argv: print 'Usage: python runtests.py [-q|--quiet|-v|--verbose] [--exit_on_failure] [tests|functional_tests|contrib_tests]' return verbosity = 1 exit_on_failure = '--exit_on_failure' in sys.argv if '-q' in sys.argv or '--quiet' in sys.argv: verbosity = 0 if "-v" in sys.argv or '--verbose' in sys.argv: verbosity = 2 if verbosity == 0: logging.disable(logging.CRITICAL) elif verbosity == 1: logging.disable(logging.ERROR) elif verbosity == 2: logging.basicConfig(level=logging.DEBUG) # Allow user to run a specific folder of tests if 'tests' in sys.argv: run('tests', verbosity, exit_on_failure) elif 'functional_tests' in sys.argv: run('functional_tests', verbosity, exit_on_failure) elif 'contrib_tests' in sys.argv: run('contrib_tests', verbosity, exit_on_failure) else: run('tests', verbosity, exit_on_failure) run('functional_tests', verbosity, exit_on_failure) run('contrib_tests', verbosity, exit_on_failure) if __name__ == '__main__': main()
Python
#!/usr/bin/env python # Copyright (c) 2010, Google Inc. # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. """Module to enforce different constraints on flags. A validator represents an invariant, enforced over a one or more flags. See 'FLAGS VALIDATORS' in flags.py's docstring for a usage manual. """ __author__ = 'olexiy@google.com (Olexiy Oryeshko)' class Error(Exception): """Thrown If validator constraint is not satisfied.""" class Validator(object): """Base class for flags validators. Users should NOT overload these classes, and use flags.Register... methods instead. """ # Used to assign each validator an unique insertion_index validators_count = 0 def __init__(self, checker, message): """Constructor to create all validators. Args: checker: function to verify the constraint. Input of this method varies, see SimpleValidator and DictionaryValidator for a detailed description. message: string, error message to be shown to the user """ self.checker = checker self.message = message Validator.validators_count += 1 # Used to assert validators in the order they were registered (CL/18694236) self.insertion_index = Validator.validators_count def Verify(self, flag_values): """Verify that constraint is satisfied. flags library calls this method to verify Validator's constraint. Args: flag_values: flags.FlagValues, containing all flags Raises: Error: if constraint is not satisfied. """ param = self._GetInputToCheckerFunction(flag_values) if not self.checker(param): raise Error(self.message) def GetFlagsNames(self): """Return the names of the flags checked by this validator. Returns: [string], names of the flags """ raise NotImplementedError('This method should be overloaded') def PrintFlagsWithValues(self, flag_values): raise NotImplementedError('This method should be overloaded') def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues, containing all flags. Returns: Return type depends on the specific validator. """ raise NotImplementedError('This method should be overloaded') class SimpleValidator(Validator): """Validator behind RegisterValidator() method. Validates that a single flag passes its checker function. The checker function takes the flag value and returns True (if value looks fine) or, if flag value is not valid, either returns False or raises an Exception.""" def __init__(self, flag_name, checker, message): """Constructor. Args: flag_name: string, name of the flag. checker: function to verify the validator. input - value of the corresponding flag (string, boolean, etc). output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise Error. message: string, error message to be shown to the user if validator's condition is not satisfied """ super(SimpleValidator, self).__init__(checker, message) self.flag_name = flag_name def GetFlagsNames(self): return [self.flag_name] def PrintFlagsWithValues(self, flag_values): return 'flag --%s=%s' % (self.flag_name, flag_values[self.flag_name].value) def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues Returns: value of the corresponding flag. """ return flag_values[self.flag_name].value class DictionaryValidator(Validator): """Validator behind RegisterDictionaryValidator method. Validates that flag values pass their common checker function. The checker function takes flag values and returns True (if values look fine) or, if values are not valid, either returns False or raises an Exception. """ def __init__(self, flag_names, checker, message): """Constructor. Args: flag_names: [string], containing names of the flags used by checker. checker: function to verify the validator. input - dictionary, with keys() being flag_names, and value for each key being the value of the corresponding flag (string, boolean, etc). output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise Error. message: string, error message to be shown to the user if validator's condition is not satisfied """ super(DictionaryValidator, self).__init__(checker, message) self.flag_names = flag_names def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues Returns: dictionary, with keys() being self.lag_names, and value for each key being the value of the corresponding flag (string, boolean, etc). """ return dict([key, flag_values[key].value] for key in self.flag_names) def PrintFlagsWithValues(self, flag_values): prefix = 'flags ' flags_with_values = [] for key in self.flag_names: flags_with_values.append('%s=%s' % (key, flag_values[key].value)) return prefix + ', '.join(flags_with_values) def GetFlagsNames(self): return self.flag_names
Python
#!/usr/bin/env python # Copyright (c) 2007, Google Inc. # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. # # --- # Author: Chad Lester # Design and style contributions by: # Amit Patel, Bogdan Cocosel, Daniel Dulitz, Eric Tiedemann, # Eric Veach, Laurence Gonsalves, Matthew Springer # Code reorganized a bit by Craig Silverstein """This module is used to define and parse command line flags. This module defines a *distributed* flag-definition policy: rather than an application having to define all flags in or near main(), each python module defines flags that are useful to it. When one python module imports another, it gains access to the other's flags. (This is implemented by having all modules share a common, global registry object containing all the flag information.) Flags are defined through the use of one of the DEFINE_xxx functions. The specific function used determines how the flag is parsed, checked, and optionally type-converted, when it's seen on the command line. IMPLEMENTATION: DEFINE_* creates a 'Flag' object and registers it with a 'FlagValues' object (typically the global FlagValues FLAGS, defined here). The 'FlagValues' object can scan the command line arguments and pass flag arguments to the corresponding 'Flag' objects for value-checking and type conversion. The converted flag values are available as attributes of the 'FlagValues' object. Code can access the flag through a FlagValues object, for instance gflags.FLAGS.myflag. Typically, the __main__ module passes the command line arguments to gflags.FLAGS for parsing. At bottom, this module calls getopt(), so getopt functionality is supported, including short- and long-style flags, and the use of -- to terminate flags. Methods defined by the flag module will throw 'FlagsError' exceptions. The exception argument will be a human-readable string. FLAG TYPES: This is a list of the DEFINE_*'s that you can do. All flags take a name, default value, help-string, and optional 'short' name (one-letter name). Some flags have other arguments, which are described with the flag. DEFINE_string: takes any input, and interprets it as a string. DEFINE_bool or DEFINE_boolean: typically does not take an argument: say --myflag to set FLAGS.myflag to true, or --nomyflag to set FLAGS.myflag to false. Alternately, you can say --myflag=true or --myflag=t or --myflag=1 or --myflag=false or --myflag=f or --myflag=0 DEFINE_float: takes an input and interprets it as a floating point number. Takes optional args lower_bound and upper_bound; if the number specified on the command line is out of range, it will raise a FlagError. DEFINE_integer: takes an input and interprets it as an integer. Takes optional args lower_bound and upper_bound as for floats. DEFINE_enum: takes a list of strings which represents legal values. If the command-line value is not in this list, raise a flag error. Otherwise, assign to FLAGS.flag as a string. DEFINE_list: Takes a comma-separated list of strings on the commandline. Stores them in a python list object. DEFINE_spaceseplist: Takes a space-separated list of strings on the commandline. Stores them in a python list object. Example: --myspacesepflag "foo bar baz" DEFINE_multistring: The same as DEFINE_string, except the flag can be specified more than once on the commandline. The result is a python list object (list of strings), even if the flag is only on the command line once. DEFINE_multi_int: The same as DEFINE_integer, except the flag can be specified more than once on the commandline. The result is a python list object (list of ints), even if the flag is only on the command line once. SPECIAL FLAGS: There are a few flags that have special meaning: --help prints a list of all the flags in a human-readable fashion --helpshort prints a list of all key flags (see below). --helpxml prints a list of all flags, in XML format. DO NOT parse the output of --help and --helpshort. Instead, parse the output of --helpxml. For more info, see "OUTPUT FOR --helpxml" below. --flagfile=foo read flags from file foo. --undefok=f1,f2 ignore unrecognized option errors for f1,f2. For boolean flags, you should use --undefok=boolflag, and --boolflag and --noboolflag will be accepted. Do not use --undefok=noboolflag. -- as in getopt(), terminates flag-processing FLAGS VALIDATORS: If your program: - requires flag X to be specified - needs flag Y to match a regular expression - or requires any more general constraint to be satisfied then validators are for you! Each validator represents a constraint over one flag, which is enforced starting from the initial parsing of the flags and until the program terminates. Also, lower_bound and upper_bound for numerical flags are enforced using flag validators. Howto: If you want to enforce a constraint over one flag, use flags.RegisterValidator(flag_name, checker, message='Flag validation failed', flag_values=FLAGS) After flag values are initially parsed, and after any change to the specified flag, method checker(flag_value) will be executed. If constraint is not satisfied, an IllegalFlagValue exception will be raised. See RegisterValidator's docstring for a detailed explanation on how to construct your own checker. EXAMPLE USAGE: FLAGS = flags.FLAGS flags.DEFINE_integer('my_version', 0, 'Version number.') flags.DEFINE_string('filename', None, 'Input file name', short_name='f') flags.RegisterValidator('my_version', lambda value: value % 2 == 0, message='--my_version must be divisible by 2') flags.MarkFlagAsRequired('filename') NOTE ON --flagfile: Flags may be loaded from text files in addition to being specified on the commandline. Any flags you don't feel like typing, throw them in a file, one flag per line, for instance: --myflag=myvalue --nomyboolean_flag You then specify your file with the special flag '--flagfile=somefile'. You CAN recursively nest flagfile= tokens OR use multiple files on the command line. Lines beginning with a single hash '#' or a double slash '//' are comments in your flagfile. Any flagfile=<file> will be interpreted as having a relative path from the current working directory rather than from the place the file was included from: myPythonScript.py --flagfile=config/somefile.cfg If somefile.cfg includes further --flagfile= directives, these will be referenced relative to the original CWD, not from the directory the including flagfile was found in! The caveat applies to people who are including a series of nested files in a different dir than they are executing out of. Relative path names are always from CWD, not from the directory of the parent include flagfile. We do now support '~' expanded directory names. Absolute path names ALWAYS work! EXAMPLE USAGE: import gflags FLAGS = gflags.FLAGS # Flag names are globally defined! So in general, we need to be # careful to pick names that are unlikely to be used by other libraries. # If there is a conflict, we'll get an error at import time. gflags.DEFINE_string('name', 'Mr. President', 'your name') gflags.DEFINE_integer('age', None, 'your age in years', lower_bound=0) gflags.DEFINE_boolean('debug', False, 'produces debugging output') gflags.DEFINE_enum('gender', 'male', ['male', 'female'], 'your gender') def main(argv): try: argv = FLAGS(argv) # parse flags except gflags.FlagsError, e: print '%s\\nUsage: %s ARGS\\n%s' % (e, sys.argv[0], FLAGS) sys.exit(1) if FLAGS.debug: print 'non-flag arguments:', argv print 'Happy Birthday', FLAGS.name if FLAGS.age is not None: print 'You are a %s, who is %d years old' % (FLAGS.gender, FLAGS.age) if __name__ == '__main__': main(sys.argv) KEY FLAGS: As we already explained, each module gains access to all flags defined by all the other modules it transitively imports. In the case of non-trivial scripts, this means a lot of flags ... For documentation purposes, it is good to identify the flags that are key (i.e., really important) to a module. Clearly, the concept of "key flag" is a subjective one. When trying to determine whether a flag is key to a module or not, assume that you are trying to explain your module to a potential user: which flags would you really like to mention first? We'll describe shortly how to declare which flags are key to a module. For the moment, assume we know the set of key flags for each module. Then, if you use the app.py module, you can use the --helpshort flag to print only the help for the flags that are key to the main module, in a human-readable format. NOTE: If you need to parse the flag help, do NOT use the output of --help / --helpshort. That output is meant for human consumption, and may be changed in the future. Instead, use --helpxml; flags that are key for the main module are marked there with a <key>yes</key> element. The set of key flags for a module M is composed of: 1. Flags defined by module M by calling a DEFINE_* function. 2. Flags that module M explictly declares as key by using the function DECLARE_key_flag(<flag_name>) 3. Key flags of other modules that M specifies by using the function ADOPT_module_key_flags(<other_module>) This is a "bulk" declaration of key flags: each flag that is key for <other_module> becomes key for the current module too. Notice that if you do not use the functions described at points 2 and 3 above, then --helpshort prints information only about the flags defined by the main module of our script. In many cases, this behavior is good enough. But if you move part of the main module code (together with the related flags) into a different module, then it is nice to use DECLARE_key_flag / ADOPT_module_key_flags and make sure --helpshort lists all relevant flags (otherwise, your code refactoring may confuse your users). Note: each of DECLARE_key_flag / ADOPT_module_key_flags has its own pluses and minuses: DECLARE_key_flag is more targeted and may lead a more focused --helpshort documentation. ADOPT_module_key_flags is good for cases when an entire module is considered key to the current script. Also, it does not require updates to client scripts when a new flag is added to the module. EXAMPLE USAGE 2 (WITH KEY FLAGS): Consider an application that contains the following three files (two auxiliary modules and a main module): File libfoo.py: import gflags gflags.DEFINE_integer('num_replicas', 3, 'Number of replicas to start') gflags.DEFINE_boolean('rpc2', True, 'Turn on the usage of RPC2.') ... some code ... File libbar.py: import gflags gflags.DEFINE_string('bar_gfs_path', '/gfs/path', 'Path to the GFS files for libbar.') gflags.DEFINE_string('email_for_bar_errors', 'bar-team@google.com', 'Email address for bug reports about module libbar.') gflags.DEFINE_boolean('bar_risky_hack', False, 'Turn on an experimental and buggy optimization.') ... some code ... File myscript.py: import gflags import libfoo import libbar gflags.DEFINE_integer('num_iterations', 0, 'Number of iterations.') # Declare that all flags that are key for libfoo are # key for this module too. gflags.ADOPT_module_key_flags(libfoo) # Declare that the flag --bar_gfs_path (defined in libbar) is key # for this module. gflags.DECLARE_key_flag('bar_gfs_path') ... some code ... When myscript is invoked with the flag --helpshort, the resulted help message lists information about all the key flags for myscript: --num_iterations, --num_replicas, --rpc2, and --bar_gfs_path (in addition to the special flags --help and --helpshort). Of course, myscript uses all the flags declared by it (in this case, just --num_replicas) or by any of the modules it transitively imports (e.g., the modules libfoo, libbar). E.g., it can access the value of FLAGS.bar_risky_hack, even if --bar_risky_hack is not declared as a key flag for myscript. OUTPUT FOR --helpxml: The --helpxml flag generates output with the following structure: <?xml version="1.0"?> <AllFlags> <program>PROGRAM_BASENAME</program> <usage>MAIN_MODULE_DOCSTRING</usage> (<flag> [<key>yes</key>] <file>DECLARING_MODULE</file> <name>FLAG_NAME</name> <meaning>FLAG_HELP_MESSAGE</meaning> <default>DEFAULT_FLAG_VALUE</default> <current>CURRENT_FLAG_VALUE</current> <type>FLAG_TYPE</type> [OPTIONAL_ELEMENTS] </flag>)* </AllFlags> Notes: 1. The output is intentionally similar to the output generated by the C++ command-line flag library. The few differences are due to the Python flags that do not have a C++ equivalent (at least not yet), e.g., DEFINE_list. 2. New XML elements may be added in the future. 3. DEFAULT_FLAG_VALUE is in serialized form, i.e., the string you can pass for this flag on the command-line. E.g., for a flag defined using DEFINE_list, this field may be foo,bar, not ['foo', 'bar']. 4. CURRENT_FLAG_VALUE is produced using str(). This means that the string 'false' will be represented in the same way as the boolean False. Using repr() would have removed this ambiguity and simplified parsing, but would have broken the compatibility with the C++ command-line flags. 5. OPTIONAL_ELEMENTS describe elements relevant for certain kinds of flags: lower_bound, upper_bound (for flags that specify bounds), enum_value (for enum flags), list_separator (for flags that consist of a list of values, separated by a special token). 6. We do not provide any example here: please use --helpxml instead. """ import cgi import getopt import os import re import string import sys import gflags_validators # Are we running at least python 2.2? try: if tuple(sys.version_info[:3]) < (2,2,0): raise NotImplementedError("requires python 2.2.0 or later") except AttributeError: # a very old python, that lacks sys.version_info raise NotImplementedError("requires python 2.2.0 or later") # If we're not running at least python 2.2.1, define True, False, and bool. # Thanks, Guido, for the code. try: True, False, bool except NameError: False = 0 True = 1 def bool(x): if x: return True else: return False # Are we running under pychecker? _RUNNING_PYCHECKER = 'pychecker.python' in sys.modules def _GetCallingModule(): """Returns the name of the module that's calling into this module. We generally use this function to get the name of the module calling a DEFINE_foo... function. """ # Walk down the stack to find the first globals dict that's not ours. for depth in range(1, sys.getrecursionlimit()): if not sys._getframe(depth).f_globals is globals(): globals_for_frame = sys._getframe(depth).f_globals module_name = _GetModuleObjectAndName(globals_for_frame)[1] if module_name is not None: return module_name raise AssertionError("No module was found") def _GetThisModuleObjectAndName(): """Returns: (module object, module name) for this module.""" return _GetModuleObjectAndName(globals()) # module exceptions: class FlagsError(Exception): """The base class for all flags errors.""" pass class DuplicateFlag(FlagsError): """Raised if there is a flag naming conflict.""" pass class DuplicateFlagCannotPropagateNoneToSwig(DuplicateFlag): """Special case of DuplicateFlag -- SWIG flag value can't be set to None. This can be raised when a duplicate flag is created. Even if allow_override is True, we still abort if the new value is None, because it's currently impossible to pass None default value back to SWIG. See FlagValues.SetDefault for details. """ pass # A DuplicateFlagError conveys more information than a # DuplicateFlag. Since there are external modules that create # DuplicateFlags, the interface to DuplicateFlag shouldn't change. class DuplicateFlagError(DuplicateFlag): def __init__(self, flagname, flag_values): self.flagname = flagname message = "The flag '%s' is defined twice." % self.flagname flags_by_module = flag_values.FlagsByModuleDict() for module in flags_by_module: for flag in flags_by_module[module]: if flag.name == flagname or flag.short_name == flagname: message = message + " First from " + module + "," break message = message + " Second from " + _GetCallingModule() DuplicateFlag.__init__(self, message) class IllegalFlagValue(FlagsError): """The flag command line argument is illegal.""" pass class UnrecognizedFlag(FlagsError): """Raised if a flag is unrecognized.""" pass # An UnrecognizedFlagError conveys more information than an UnrecognizedFlag. # Since there are external modules that create DuplicateFlags, the interface to # DuplicateFlag shouldn't change. The flagvalue will be assigned the full value # of the flag and its argument, if any, allowing handling of unrecognzed flags # in an exception handler. # If flagvalue is the empty string, then this exception is an due to a # reference to a flag that was not already defined. class UnrecognizedFlagError(UnrecognizedFlag): def __init__(self, flagname, flagvalue=''): self.flagname = flagname self.flagvalue = flagvalue UnrecognizedFlag.__init__( self, "Unknown command line flag '%s'" % flagname) # Global variable used by expvar _exported_flags = {} _help_width = 80 # width of help output def GetHelpWidth(): """Returns: an integer, the width of help lines that is used in TextWrap.""" return _help_width def CutCommonSpacePrefix(text): """Removes a common space prefix from the lines of a multiline text. If the first line does not start with a space, it is left as it is and only in the remaining lines a common space prefix is being searched for. That means the first line will stay untouched. This is especially useful to turn doc strings into help texts. This is because some people prefer to have the doc comment start already after the apostrophy and then align the following lines while others have the apostrophies on a seperately line. The function also drops trailing empty lines and ignores empty lines following the initial content line while calculating the initial common whitespace. Args: text: text to work on Returns: the resulting text """ text_lines = text.splitlines() # Drop trailing empty lines while text_lines and not text_lines[-1]: text_lines = text_lines[:-1] if text_lines: # We got some content, is the first line starting with a space? if text_lines[0] and text_lines[0][0].isspace(): text_first_line = [] else: text_first_line = [text_lines.pop(0)] # Calculate length of common leading whitesppace (only over content lines) common_prefix = os.path.commonprefix([line for line in text_lines if line]) space_prefix_len = len(common_prefix) - len(common_prefix.lstrip()) # If we have a common space prefix, drop it from all lines if space_prefix_len: for index in xrange(len(text_lines)): if text_lines[index]: text_lines[index] = text_lines[index][space_prefix_len:] return '\n'.join(text_first_line + text_lines) return '' def TextWrap(text, length=None, indent='', firstline_indent=None, tabs=' '): """Wraps a given text to a maximum line length and returns it. We turn lines that only contain whitespaces into empty lines. We keep new lines and tabs (e.g., we do not treat tabs as spaces). Args: text: text to wrap length: maximum length of a line, includes indentation if this is None then use GetHelpWidth() indent: indent for all but first line firstline_indent: indent for first line; if None, fall back to indent tabs: replacement for tabs Returns: wrapped text Raises: FlagsError: if indent not shorter than length FlagsError: if firstline_indent not shorter than length """ # Get defaults where callee used None if length is None: length = GetHelpWidth() if indent is None: indent = '' if len(indent) >= length: raise FlagsError('Indent must be shorter than length') # In line we will be holding the current line which is to be started # with indent (or firstline_indent if available) and then appended # with words. if firstline_indent is None: firstline_indent = '' line = indent else: line = firstline_indent if len(firstline_indent) >= length: raise FlagsError('First iline indent must be shorter than length') # If the callee does not care about tabs we simply convert them to # spaces If callee wanted tabs to be single space then we do that # already here. if not tabs or tabs == ' ': text = text.replace('\t', ' ') else: tabs_are_whitespace = not tabs.strip() line_regex = re.compile('([ ]*)(\t*)([^ \t]+)', re.MULTILINE) # Split the text into lines and the lines with the regex above. The # resulting lines are collected in result[]. For each split we get the # spaces, the tabs and the next non white space (e.g. next word). result = [] for text_line in text.splitlines(): # Store result length so we can find out whether processing the next # line gave any new content old_result_len = len(result) # Process next line with line_regex. For optimization we do an rstrip(). # - process tabs (changes either line or word, see below) # - process word (first try to squeeze on line, then wrap or force wrap) # Spaces found on the line are ignored, they get added while wrapping as # needed. for spaces, current_tabs, word in line_regex.findall(text_line.rstrip()): # If tabs weren't converted to spaces, handle them now if current_tabs: # If the last thing we added was a space anyway then drop # it. But let's not get rid of the indentation. if (((result and line != indent) or (not result and line != firstline_indent)) and line[-1] == ' '): line = line[:-1] # Add the tabs, if that means adding whitespace, just add it at # the line, the rstrip() code while shorten the line down if # necessary if tabs_are_whitespace: line += tabs * len(current_tabs) else: # if not all tab replacement is whitespace we prepend it to the word word = tabs * len(current_tabs) + word # Handle the case where word cannot be squeezed onto current last line if len(line) + len(word) > length and len(indent) + len(word) <= length: result.append(line.rstrip()) line = indent + word word = '' # No space left on line or can we append a space? if len(line) + 1 >= length: result.append(line.rstrip()) line = indent else: line += ' ' # Add word and shorten it up to allowed line length. Restart next # line with indent and repeat, or add a space if we're done (word # finished) This deals with words that caanot fit on one line # (e.g. indent + word longer than allowed line length). while len(line) + len(word) >= length: line += word result.append(line[:length]) word = line[length:] line = indent # Default case, simply append the word and a space if word: line += word + ' ' # End of input line. If we have content we finish the line. If the # current line is just the indent but we had content in during this # original line then we need to add an emoty line. if (result and line != indent) or (not result and line != firstline_indent): result.append(line.rstrip()) elif len(result) == old_result_len: result.append('') line = indent return '\n'.join(result) def DocToHelp(doc): """Takes a __doc__ string and reformats it as help.""" # Get rid of starting and ending white space. Using lstrip() or even # strip() could drop more than maximum of first line and right space # of last line. doc = doc.strip() # Get rid of all empty lines whitespace_only_line = re.compile('^[ \t]+$', re.M) doc = whitespace_only_line.sub('', doc) # Cut out common space at line beginnings doc = CutCommonSpacePrefix(doc) # Just like this module's comment, comments tend to be aligned somehow. # In other words they all start with the same amount of white space # 1) keep double new lines # 2) keep ws after new lines if not empty line # 3) all other new lines shall be changed to a space # Solution: Match new lines between non white space and replace with space. doc = re.sub('(?<=\S)\n(?=\S)', ' ', doc, re.M) return doc def _GetModuleObjectAndName(globals_dict): """Returns the module that defines a global environment, and its name. Args: globals_dict: A dictionary that should correspond to an environment providing the values of the globals. Returns: A pair consisting of (1) module object and (2) module name (a string). Returns (None, None) if the module could not be identified. """ # The use of .items() (instead of .iteritems()) is NOT a mistake: if # a parallel thread imports a module while we iterate over # .iteritems() (not nice, but possible), we get a RuntimeError ... # Hence, we use the slightly slower but safer .items(). for name, module in sys.modules.items(): if getattr(module, '__dict__', None) is globals_dict: if name == '__main__': # Pick a more informative name for the main module. name = sys.argv[0] return (module, name) return (None, None) def _GetMainModule(): """Returns the name of the module from which execution started.""" for depth in range(1, sys.getrecursionlimit()): try: globals_of_main = sys._getframe(depth).f_globals except ValueError: return _GetModuleObjectAndName(globals_of_main)[1] raise AssertionError("No module was found") class FlagValues: """Registry of 'Flag' objects. A 'FlagValues' can then scan command line arguments, passing flag arguments through to the 'Flag' objects that it owns. It also provides easy access to the flag values. Typically only one 'FlagValues' object is needed by an application: gflags.FLAGS This class is heavily overloaded: 'Flag' objects are registered via __setitem__: FLAGS['longname'] = x # register a new flag The .value attribute of the registered 'Flag' objects can be accessed as attributes of this 'FlagValues' object, through __getattr__. Both the long and short name of the original 'Flag' objects can be used to access its value: FLAGS.longname # parsed flag value FLAGS.x # parsed flag value (short name) Command line arguments are scanned and passed to the registered 'Flag' objects through the __call__ method. Unparsed arguments, including argv[0] (e.g. the program name) are returned. argv = FLAGS(sys.argv) # scan command line arguments The original registered Flag objects can be retrieved through the use of the dictionary-like operator, __getitem__: x = FLAGS['longname'] # access the registered Flag object The str() operator of a 'FlagValues' object provides help for all of the registered 'Flag' objects. """ def __init__(self): # Since everything in this class is so heavily overloaded, the only # way of defining and using fields is to access __dict__ directly. # Dictionary: flag name (string) -> Flag object. self.__dict__['__flags'] = {} # Dictionary: module name (string) -> list of Flag objects that are defined # by that module. self.__dict__['__flags_by_module'] = {} # Dictionary: module name (string) -> list of Flag objects that are # key for that module. self.__dict__['__key_flags_by_module'] = {} # Set if we should use new style gnu_getopt rather than getopt when parsing # the args. Only possible with Python 2.3+ self.UseGnuGetOpt(False) def UseGnuGetOpt(self, use_gnu_getopt=True): self.__dict__['__use_gnu_getopt'] = use_gnu_getopt def IsGnuGetOpt(self): return self.__dict__['__use_gnu_getopt'] def FlagDict(self): return self.__dict__['__flags'] def FlagsByModuleDict(self): """Returns the dictionary of module_name -> list of defined flags. Returns: A dictionary. Its keys are module names (strings). Its values are lists of Flag objects. """ return self.__dict__['__flags_by_module'] def KeyFlagsByModuleDict(self): """Returns the dictionary of module_name -> list of key flags. Returns: A dictionary. Its keys are module names (strings). Its values are lists of Flag objects. """ return self.__dict__['__key_flags_by_module'] def _RegisterFlagByModule(self, module_name, flag): """Records the module that defines a specific flag. We keep track of which flag is defined by which module so that we can later sort the flags by module. Args: module_name: A string, the name of a Python module. flag: A Flag object, a flag that is key to the module. """ flags_by_module = self.FlagsByModuleDict() flags_by_module.setdefault(module_name, []).append(flag) def _RegisterKeyFlagForModule(self, module_name, flag): """Specifies that a flag is a key flag for a module. Args: module_name: A string, the name of a Python module. flag: A Flag object, a flag that is key to the module. """ key_flags_by_module = self.KeyFlagsByModuleDict() # The list of key flags for the module named module_name. key_flags = key_flags_by_module.setdefault(module_name, []) # Add flag, but avoid duplicates. if flag not in key_flags: key_flags.append(flag) def _GetFlagsDefinedByModule(self, module): """Returns the list of flags defined by a module. Args: module: A module object or a module name (a string). Returns: A new list of Flag objects. Caller may update this list as he wishes: none of those changes will affect the internals of this FlagValue object. """ if not isinstance(module, str): module = module.__name__ return list(self.FlagsByModuleDict().get(module, [])) def _GetKeyFlagsForModule(self, module): """Returns the list of key flags for a module. Args: module: A module object or a module name (a string) Returns: A new list of Flag objects. Caller may update this list as he wishes: none of those changes will affect the internals of this FlagValue object. """ if not isinstance(module, str): module = module.__name__ # Any flag is a key flag for the module that defined it. NOTE: # key_flags is a fresh list: we can update it without affecting the # internals of this FlagValues object. key_flags = self._GetFlagsDefinedByModule(module) # Take into account flags explicitly declared as key for a module. for flag in self.KeyFlagsByModuleDict().get(module, []): if flag not in key_flags: key_flags.append(flag) return key_flags def AppendFlagValues(self, flag_values): """Appends flags registered in another FlagValues instance. Args: flag_values: registry to copy from """ for flag_name, flag in flag_values.FlagDict().iteritems(): # Each flags with shortname appears here twice (once under its # normal name, and again with its short name). To prevent # problems (DuplicateFlagError) with double flag registration, we # perform a check to make sure that the entry we're looking at is # for its normal name. if flag_name == flag.name: self[flag_name] = flag def RemoveFlagValues(self, flag_values): """Remove flags that were previously appended from another FlagValues. Args: flag_values: registry containing flags to remove. """ for flag_name in flag_values.FlagDict(): self.__delattr__(flag_name) def __setitem__(self, name, flag): """Registers a new flag variable.""" fl = self.FlagDict() if not isinstance(flag, Flag): raise IllegalFlagValue(flag) if not isinstance(name, type("")): raise FlagsError("Flag name must be a string") if len(name) == 0: raise FlagsError("Flag name cannot be empty") # If running under pychecker, duplicate keys are likely to be # defined. Disable check for duplicate keys when pycheck'ing. if (fl.has_key(name) and not flag.allow_override and not fl[name].allow_override and not _RUNNING_PYCHECKER): raise DuplicateFlagError(name, self) short_name = flag.short_name if short_name is not None: if (fl.has_key(short_name) and not flag.allow_override and not fl[short_name].allow_override and not _RUNNING_PYCHECKER): raise DuplicateFlagError(short_name, self) fl[short_name] = flag fl[name] = flag global _exported_flags _exported_flags[name] = flag def __getitem__(self, name): """Retrieves the Flag object for the flag --name.""" return self.FlagDict()[name] def __getattr__(self, name): """Retrieves the 'value' attribute of the flag --name.""" fl = self.FlagDict() if not fl.has_key(name): raise AttributeError(name) return fl[name].value def __setattr__(self, name, value): """Sets the 'value' attribute of the flag --name.""" fl = self.FlagDict() fl[name].value = value self._AssertValidators(fl[name].validators) return value def _AssertAllValidators(self): all_validators = set() for flag in self.FlagDict().itervalues(): for validator in flag.validators: all_validators.add(validator) self._AssertValidators(all_validators) def _AssertValidators(self, validators): """Assert if all validators in the list are satisfied. Asserts validators in the order they were created. Args: validators: Iterable(gflags_validators.Validator), validators to be verified Raises: AttributeError: if validators work with a non-existing flag. IllegalFlagValue: if validation fails for at least one validator """ for validator in sorted( validators, key=lambda validator: validator.insertion_index): try: validator.Verify(self) except gflags_validators.Error, e: message = validator.PrintFlagsWithValues(self) raise IllegalFlagValue('%s: %s' % (message, str(e))) def _FlagIsRegistered(self, flag_obj): """Checks whether a Flag object is registered under some name. Note: this is non trivial: in addition to its normal name, a flag may have a short name too. In self.FlagDict(), both the normal and the short name are mapped to the same flag object. E.g., calling only "del FLAGS.short_name" is not unregistering the corresponding Flag object (it is still registered under the longer name). Args: flag_obj: A Flag object. Returns: A boolean: True iff flag_obj is registered under some name. """ flag_dict = self.FlagDict() # Check whether flag_obj is registered under its long name. name = flag_obj.name if flag_dict.get(name, None) == flag_obj: return True # Check whether flag_obj is registered under its short name. short_name = flag_obj.short_name if (short_name is not None and flag_dict.get(short_name, None) == flag_obj): return True # The flag cannot be registered under any other name, so we do not # need to do a full search through the values of self.FlagDict(). return False def __delattr__(self, flag_name): """Deletes a previously-defined flag from a flag object. This method makes sure we can delete a flag by using del flag_values_object.<flag_name> E.g., flags.DEFINE_integer('foo', 1, 'Integer flag.') del flags.FLAGS.foo Args: flag_name: A string, the name of the flag to be deleted. Raises: AttributeError: When there is no registered flag named flag_name. """ fl = self.FlagDict() if flag_name not in fl: raise AttributeError(flag_name) flag_obj = fl[flag_name] del fl[flag_name] if not self._FlagIsRegistered(flag_obj): # If the Flag object indicated by flag_name is no longer # registered (please see the docstring of _FlagIsRegistered), then # we delete the occurences of the flag object in all our internal # dictionaries. self.__RemoveFlagFromDictByModule(self.FlagsByModuleDict(), flag_obj) self.__RemoveFlagFromDictByModule(self.KeyFlagsByModuleDict(), flag_obj) def __RemoveFlagFromDictByModule(self, flags_by_module_dict, flag_obj): """Removes a flag object from a module -> list of flags dictionary. Args: flags_by_module_dict: A dictionary that maps module names to lists of flags. flag_obj: A flag object. """ for unused_module, flags_in_module in flags_by_module_dict.iteritems(): # while (as opposed to if) takes care of multiple occurences of a # flag in the list for the same module. while flag_obj in flags_in_module: flags_in_module.remove(flag_obj) def SetDefault(self, name, value): """Changes the default value of the named flag object.""" fl = self.FlagDict() if not fl.has_key(name): raise AttributeError(name) fl[name].SetDefault(value) self._AssertValidators(fl[name].validators) def __contains__(self, name): """Returns True if name is a value (flag) in the dict.""" return name in self.FlagDict() has_key = __contains__ # a synonym for __contains__() def __iter__(self): return self.FlagDict().iterkeys() def __call__(self, argv): """Parses flags from argv; stores parsed flags into this FlagValues object. All unparsed arguments are returned. Flags are parsed using the GNU Program Argument Syntax Conventions, using getopt: http://www.gnu.org/software/libc/manual/html_mono/libc.html#Getopt Args: argv: argument list. Can be of any type that may be converted to a list. Returns: The list of arguments not parsed as options, including argv[0] Raises: FlagsError: on any parsing error """ # Support any sequence type that can be converted to a list argv = list(argv) shortopts = "" longopts = [] fl = self.FlagDict() # This pre parses the argv list for --flagfile=<> options. argv = argv[:1] + self.ReadFlagsFromFiles(argv[1:], force_gnu=False) # Correct the argv to support the google style of passing boolean # parameters. Boolean parameters may be passed by using --mybool, # --nomybool, --mybool=(true|false|1|0). getopt does not support # having options that may or may not have a parameter. We replace # instances of the short form --mybool and --nomybool with their # full forms: --mybool=(true|false). original_argv = list(argv) # list() makes a copy shortest_matches = None for name, flag in fl.items(): if not flag.boolean: continue if shortest_matches is None: # Determine the smallest allowable prefix for all flag names shortest_matches = self.ShortestUniquePrefixes(fl) no_name = 'no' + name prefix = shortest_matches[name] no_prefix = shortest_matches[no_name] # Replace all occurences of this boolean with extended forms for arg_idx in range(1, len(argv)): arg = argv[arg_idx] if arg.find('=') >= 0: continue if arg.startswith('--'+prefix) and ('--'+name).startswith(arg): argv[arg_idx] = ('--%s=true' % name) elif arg.startswith('--'+no_prefix) and ('--'+no_name).startswith(arg): argv[arg_idx] = ('--%s=false' % name) # Loop over all of the flags, building up the lists of short options # and long options that will be passed to getopt. Short options are # specified as a string of letters, each letter followed by a colon # if it takes an argument. Long options are stored in an array of # strings. Each string ends with an '=' if it takes an argument. for name, flag in fl.items(): longopts.append(name + "=") if len(name) == 1: # one-letter option: allow short flag type also shortopts += name if not flag.boolean: shortopts += ":" longopts.append('undefok=') undefok_flags = [] # In case --undefok is specified, loop to pick up unrecognized # options one by one. unrecognized_opts = [] args = argv[1:] while True: try: if self.__dict__['__use_gnu_getopt']: optlist, unparsed_args = getopt.gnu_getopt(args, shortopts, longopts) else: optlist, unparsed_args = getopt.getopt(args, shortopts, longopts) break except getopt.GetoptError, e: if not e.opt or e.opt in fl: # Not an unrecognized option, reraise the exception as a FlagsError raise FlagsError(e) # Remove offender from args and try again for arg_index in range(len(args)): if ((args[arg_index] == '--' + e.opt) or (args[arg_index] == '-' + e.opt) or (args[arg_index].startswith('--' + e.opt + '='))): unrecognized_opts.append((e.opt, args[arg_index])) args = args[0:arg_index] + args[arg_index+1:] break else: # We should have found the option, so we don't expect to get # here. We could assert, but raising the original exception # might work better. raise FlagsError(e) for name, arg in optlist: if name == '--undefok': flag_names = arg.split(',') undefok_flags.extend(flag_names) # For boolean flags, if --undefok=boolflag is specified, then we should # also accept --noboolflag, in addition to --boolflag. # Since we don't know the type of the undefok'd flag, this will affect # non-boolean flags as well. # NOTE: You shouldn't use --undefok=noboolflag, because then we will # accept --nonoboolflag here. We are choosing not to do the conversion # from noboolflag -> boolflag because of the ambiguity that flag names # can start with 'no'. undefok_flags.extend('no' + name for name in flag_names) continue if name.startswith('--'): # long option name = name[2:] short_option = 0 else: # short option name = name[1:] short_option = 1 if fl.has_key(name): flag = fl[name] if flag.boolean and short_option: arg = 1 flag.Parse(arg) # If there were unrecognized options, raise an exception unless # the options were named via --undefok. for opt, value in unrecognized_opts: if opt not in undefok_flags: raise UnrecognizedFlagError(opt, value) if unparsed_args: if self.__dict__['__use_gnu_getopt']: # if using gnu_getopt just return the program name + remainder of argv. ret_val = argv[:1] + unparsed_args else: # unparsed_args becomes the first non-flag detected by getopt to # the end of argv. Because argv may have been modified above, # return original_argv for this region. ret_val = argv[:1] + original_argv[-len(unparsed_args):] else: ret_val = argv[:1] self._AssertAllValidators() return ret_val def Reset(self): """Resets the values to the point before FLAGS(argv) was called.""" for f in self.FlagDict().values(): f.Unparse() def RegisteredFlags(self): """Returns: a list of the names and short names of all registered flags.""" return self.FlagDict().keys() def FlagValuesDict(self): """Returns: a dictionary that maps flag names to flag values.""" flag_values = {} for flag_name in self.RegisteredFlags(): flag = self.FlagDict()[flag_name] flag_values[flag_name] = flag.value return flag_values def __str__(self): """Generates a help string for all known flags.""" return self.GetHelp() def GetHelp(self, prefix=''): """Generates a help string for all known flags.""" helplist = [] flags_by_module = self.FlagsByModuleDict() if flags_by_module: modules = flags_by_module.keys() modules.sort() # Print the help for the main module first, if possible. main_module = _GetMainModule() if main_module in modules: modules.remove(main_module) modules = [main_module] + modules for module in modules: self.__RenderOurModuleFlags(module, helplist) self.__RenderModuleFlags('gflags', _SPECIAL_FLAGS.FlagDict().values(), helplist) else: # Just print one long list of flags. self.__RenderFlagList( self.FlagDict().values() + _SPECIAL_FLAGS.FlagDict().values(), helplist, prefix) return '\n'.join(helplist) def __RenderModuleFlags(self, module, flags, output_lines, prefix=""): """Generates a help string for a given module.""" if not isinstance(module, str): module = module.__name__ output_lines.append('\n%s%s:' % (prefix, module)) self.__RenderFlagList(flags, output_lines, prefix + " ") def __RenderOurModuleFlags(self, module, output_lines, prefix=""): """Generates a help string for a given module.""" flags = self._GetFlagsDefinedByModule(module) if flags: self.__RenderModuleFlags(module, flags, output_lines, prefix) def __RenderOurModuleKeyFlags(self, module, output_lines, prefix=""): """Generates a help string for the key flags of a given module. Args: module: A module object or a module name (a string). output_lines: A list of strings. The generated help message lines will be appended to this list. prefix: A string that is prepended to each generated help line. """ key_flags = self._GetKeyFlagsForModule(module) if key_flags: self.__RenderModuleFlags(module, key_flags, output_lines, prefix) def ModuleHelp(self, module): """Describe the key flags of a module. Args: module: A module object or a module name (a string). Returns: string describing the key flags of a module. """ helplist = [] self.__RenderOurModuleKeyFlags(module, helplist) return '\n'.join(helplist) def MainModuleHelp(self): """Describe the key flags of the main module. Returns: string describing the key flags of a module. """ return self.ModuleHelp(_GetMainModule()) def __RenderFlagList(self, flaglist, output_lines, prefix=" "): fl = self.FlagDict() special_fl = _SPECIAL_FLAGS.FlagDict() flaglist = [(flag.name, flag) for flag in flaglist] flaglist.sort() flagset = {} for (name, flag) in flaglist: # It's possible this flag got deleted or overridden since being # registered in the per-module flaglist. Check now against the # canonical source of current flag information, the FlagDict. if fl.get(name, None) != flag and special_fl.get(name, None) != flag: # a different flag is using this name now continue # only print help once if flagset.has_key(flag): continue flagset[flag] = 1 flaghelp = "" if flag.short_name: flaghelp += "-%s," % flag.short_name if flag.boolean: flaghelp += "--[no]%s" % flag.name + ":" else: flaghelp += "--%s" % flag.name + ":" flaghelp += " " if flag.help: flaghelp += flag.help flaghelp = TextWrap(flaghelp, indent=prefix+" ", firstline_indent=prefix) if flag.default_as_str: flaghelp += "\n" flaghelp += TextWrap("(default: %s)" % flag.default_as_str, indent=prefix+" ") if flag.parser.syntactic_help: flaghelp += "\n" flaghelp += TextWrap("(%s)" % flag.parser.syntactic_help, indent=prefix+" ") output_lines.append(flaghelp) def get(self, name, default): """Returns the value of a flag (if not None) or a default value. Args: name: A string, the name of a flag. default: Default value to use if the flag value is None. """ value = self.__getattr__(name) if value is not None: # Can't do if not value, b/c value might be '0' or "" return value else: return default def ShortestUniquePrefixes(self, fl): """Returns: dictionary; maps flag names to their shortest unique prefix.""" # Sort the list of flag names sorted_flags = [] for name, flag in fl.items(): sorted_flags.append(name) if flag.boolean: sorted_flags.append('no%s' % name) sorted_flags.sort() # For each name in the sorted list, determine the shortest unique # prefix by comparing itself to the next name and to the previous # name (the latter check uses cached info from the previous loop). shortest_matches = {} prev_idx = 0 for flag_idx in range(len(sorted_flags)): curr = sorted_flags[flag_idx] if flag_idx == (len(sorted_flags) - 1): next = None else: next = sorted_flags[flag_idx+1] next_len = len(next) for curr_idx in range(len(curr)): if (next is None or curr_idx >= next_len or curr[curr_idx] != next[curr_idx]): # curr longer than next or no more chars in common shortest_matches[curr] = curr[:max(prev_idx, curr_idx) + 1] prev_idx = curr_idx break else: # curr shorter than (or equal to) next shortest_matches[curr] = curr prev_idx = curr_idx + 1 # next will need at least one more char return shortest_matches def __IsFlagFileDirective(self, flag_string): """Checks whether flag_string contain a --flagfile=<foo> directive.""" if isinstance(flag_string, type("")): if flag_string.startswith('--flagfile='): return 1 elif flag_string == '--flagfile': return 1 elif flag_string.startswith('-flagfile='): return 1 elif flag_string == '-flagfile': return 1 else: return 0 return 0 def ExtractFilename(self, flagfile_str): """Returns filename from a flagfile_str of form -[-]flagfile=filename. The cases of --flagfile foo and -flagfile foo shouldn't be hitting this function, as they are dealt with in the level above this function. """ if flagfile_str.startswith('--flagfile='): return os.path.expanduser((flagfile_str[(len('--flagfile=')):]).strip()) elif flagfile_str.startswith('-flagfile='): return os.path.expanduser((flagfile_str[(len('-flagfile=')):]).strip()) else: raise FlagsError('Hit illegal --flagfile type: %s' % flagfile_str) def __GetFlagFileLines(self, filename, parsed_file_list): """Returns the useful (!=comments, etc) lines from a file with flags. Args: filename: A string, the name of the flag file. parsed_file_list: A list of the names of the files we have already read. MUTATED BY THIS FUNCTION. Returns: List of strings. See the note below. NOTE(springer): This function checks for a nested --flagfile=<foo> tag and handles the lower file recursively. It returns a list of all the lines that _could_ contain command flags. This is EVERYTHING except whitespace lines and comments (lines starting with '#' or '//'). """ line_list = [] # All line from flagfile. flag_line_list = [] # Subset of lines w/o comments, blanks, flagfile= tags. try: file_obj = open(filename, 'r') except IOError, e_msg: print e_msg print 'ERROR:: Unable to open flagfile: %s' % (filename) return flag_line_list line_list = file_obj.readlines() file_obj.close() parsed_file_list.append(filename) # This is where we check each line in the file we just read. for line in line_list: if line.isspace(): pass # Checks for comment (a line that starts with '#'). elif line.startswith('#') or line.startswith('//'): pass # Checks for a nested "--flagfile=<bar>" flag in the current file. # If we find one, recursively parse down into that file. elif self.__IsFlagFileDirective(line): sub_filename = self.ExtractFilename(line) # We do a little safety check for reparsing a file we've already done. if not sub_filename in parsed_file_list: included_flags = self.__GetFlagFileLines(sub_filename, parsed_file_list) flag_line_list.extend(included_flags) else: # Case of hitting a circularly included file. print >>sys.stderr, ('Warning: Hit circular flagfile dependency: %s' % sub_filename) else: # Any line that's not a comment or a nested flagfile should get # copied into 2nd position. This leaves earlier arguements # further back in the list, thus giving them higher priority. flag_line_list.append(line.strip()) return flag_line_list def ReadFlagsFromFiles(self, argv, force_gnu=True): """Processes command line args, but also allow args to be read from file. Args: argv: A list of strings, usually sys.argv[1:], which may contain one or more flagfile directives of the form --flagfile="./filename". Note that the name of the program (sys.argv[0]) should be omitted. force_gnu: If False, --flagfile parsing obeys normal flag semantics. If True, --flagfile parsing instead follows gnu_getopt semantics. *** WARNING *** force_gnu=False may become the future default! Returns: A new list which has the original list combined with what we read from any flagfile(s). References: Global gflags.FLAG class instance. This function should be called before the normal FLAGS(argv) call. This function scans the input list for a flag that looks like: --flagfile=<somefile>. Then it opens <somefile>, reads all valid key and value pairs and inserts them into the input list between the first item of the list and any subsequent items in the list. Note that your application's flags are still defined the usual way using gflags DEFINE_flag() type functions. Notes (assuming we're getting a commandline of some sort as our input): --> Flags from the command line argv _should_ always take precedence! --> A further "--flagfile=<otherfile.cfg>" CAN be nested in a flagfile. It will be processed after the parent flag file is done. --> For duplicate flags, first one we hit should "win". --> In a flagfile, a line beginning with # or // is a comment. --> Entirely blank lines _should_ be ignored. """ parsed_file_list = [] rest_of_args = argv new_argv = [] while rest_of_args: current_arg = rest_of_args[0] rest_of_args = rest_of_args[1:] if self.__IsFlagFileDirective(current_arg): # This handles the case of -(-)flagfile foo. In this case the # next arg really is part of this one. if current_arg == '--flagfile' or current_arg == '-flagfile': if not rest_of_args: raise IllegalFlagValue('--flagfile with no argument') flag_filename = os.path.expanduser(rest_of_args[0]) rest_of_args = rest_of_args[1:] else: # This handles the case of (-)-flagfile=foo. flag_filename = self.ExtractFilename(current_arg) new_argv[0:0] = self.__GetFlagFileLines(flag_filename, parsed_file_list) else: new_argv.append(current_arg) # Stop parsing after '--', like getopt and gnu_getopt. if current_arg == '--': break # Stop parsing after a non-flag, like getopt. if not current_arg.startswith('-'): if not force_gnu and not self.__dict__['__use_gnu_getopt']: break if rest_of_args: new_argv.extend(rest_of_args) return new_argv def FlagsIntoString(self): """Returns a string with the flags assignments from this FlagValues object. This function ignores flags whose value is None. Each flag assignment is separated by a newline. NOTE: MUST mirror the behavior of the C++ function CommandlineFlagsIntoString from google3/base/commandlineflags.cc. """ s = '' for flag in self.FlagDict().values(): if flag.value is not None: s += flag.Serialize() + '\n' return s def AppendFlagsIntoFile(self, filename): """Appends all flags assignments from this FlagInfo object to a file. Output will be in the format of a flagfile. NOTE: MUST mirror the behavior of the C++ version of AppendFlagsIntoFile from google3/base/commandlineflags.cc. """ out_file = open(filename, 'a') out_file.write(self.FlagsIntoString()) out_file.close() def WriteHelpInXMLFormat(self, outfile=None): """Outputs flag documentation in XML format. NOTE: We use element names that are consistent with those used by the C++ command-line flag library, from google3/base/commandlineflags_reporting.cc. We also use a few new elements (e.g., <key>), but we do not interfere / overlap with existing XML elements used by the C++ library. Please maintain this consistency. Args: outfile: File object we write to. Default None means sys.stdout. """ outfile = outfile or sys.stdout outfile.write('<?xml version=\"1.0\"?>\n') outfile.write('<AllFlags>\n') indent = ' ' _WriteSimpleXMLElement(outfile, 'program', os.path.basename(sys.argv[0]), indent) usage_doc = sys.modules['__main__'].__doc__ if not usage_doc: usage_doc = '\nUSAGE: %s [flags]\n' % sys.argv[0] else: usage_doc = usage_doc.replace('%s', sys.argv[0]) _WriteSimpleXMLElement(outfile, 'usage', usage_doc, indent) # Get list of key flags for the main module. key_flags = self._GetKeyFlagsForModule(_GetMainModule()) # Sort flags by declaring module name and next by flag name. flags_by_module = self.FlagsByModuleDict() all_module_names = list(flags_by_module.keys()) all_module_names.sort() for module_name in all_module_names: flag_list = [(f.name, f) for f in flags_by_module[module_name]] flag_list.sort() for unused_flag_name, flag in flag_list: is_key = flag in key_flags flag.WriteInfoInXMLFormat(outfile, module_name, is_key=is_key, indent=indent) outfile.write('</AllFlags>\n') outfile.flush() def AddValidator(self, validator): """Register new flags validator to be checked. Args: validator: gflags_validators.Validator Raises: AttributeError: if validators work with a non-existing flag. """ for flag_name in validator.GetFlagsNames(): flag = self.FlagDict()[flag_name] flag.validators.append(validator) # end of FlagValues definition # The global FlagValues instance FLAGS = FlagValues() def _MakeXMLSafe(s): """Escapes <, >, and & from s, and removes XML 1.0-illegal chars.""" s = cgi.escape(s) # Escape <, >, and & # Remove characters that cannot appear in an XML 1.0 document # (http://www.w3.org/TR/REC-xml/#charsets). # # NOTE: if there are problems with current solution, one may move to # XML 1.1, which allows such chars, if they're entity-escaped (&#xHH;). s = re.sub(r'[\x00-\x08\x0b\x0c\x0e-\x1f]', '', s) return s def _WriteSimpleXMLElement(outfile, name, value, indent): """Writes a simple XML element. Args: outfile: File object we write the XML element to. name: A string, the name of XML element. value: A Python object, whose string representation will be used as the value of the XML element. indent: A string, prepended to each line of generated output. """ value_str = str(value) if isinstance(value, bool): # Display boolean values as the C++ flag library does: no caps. value_str = value_str.lower() outfile.write('%s<%s>%s</%s>\n' % (indent, name, _MakeXMLSafe(value_str), name)) class Flag: """Information about a command-line flag. 'Flag' objects define the following fields: .name - the name for this flag .default - the default value for this flag .default_as_str - default value as repr'd string, e.g., "'true'" (or None) .value - the most recent parsed value of this flag; set by Parse() .help - a help string or None if no help is available .short_name - the single letter alias for this flag (or None) .boolean - if 'true', this flag does not accept arguments .present - true if this flag was parsed from command line flags. .parser - an ArgumentParser object .serializer - an ArgumentSerializer object .allow_override - the flag may be redefined without raising an error The only public method of a 'Flag' object is Parse(), but it is typically only called by a 'FlagValues' object. The Parse() method is a thin wrapper around the 'ArgumentParser' Parse() method. The parsed value is saved in .value, and the .present attribute is updated. If this flag was already present, a FlagsError is raised. Parse() is also called during __init__ to parse the default value and initialize the .value attribute. This enables other python modules to safely use flags even if the __main__ module neglects to parse the command line arguments. The .present attribute is cleared after __init__ parsing. If the default value is set to None, then the __init__ parsing step is skipped and the .value attribute is initialized to None. Note: The default value is also presented to the user in the help string, so it is important that it be a legal value for this flag. """ def __init__(self, parser, serializer, name, default, help_string, short_name=None, boolean=0, allow_override=0): self.name = name if not help_string: help_string = '(no help available)' self.help = help_string self.short_name = short_name self.boolean = boolean self.present = 0 self.parser = parser self.serializer = serializer self.allow_override = allow_override self.value = None self.validators = [] self.SetDefault(default) def __GetParsedValueAsString(self, value): if value is None: return None if self.serializer: return repr(self.serializer.Serialize(value)) if self.boolean: if value: return repr('true') else: return repr('false') return repr(str(value)) def Parse(self, argument): try: self.value = self.parser.Parse(argument) except ValueError, e: # recast ValueError as IllegalFlagValue raise IllegalFlagValue("flag --%s=%s: %s" % (self.name, argument, e)) self.present += 1 def Unparse(self): if self.default is None: self.value = None else: self.Parse(self.default) self.present = 0 def Serialize(self): if self.value is None: return '' if self.boolean: if self.value: return "--%s" % self.name else: return "--no%s" % self.name else: if not self.serializer: raise FlagsError("Serializer not present for flag %s" % self.name) return "--%s=%s" % (self.name, self.serializer.Serialize(self.value)) def SetDefault(self, value): """Changes the default value (and current value too) for this Flag.""" # We can't allow a None override because it may end up not being # passed to C++ code when we're overriding C++ flags. So we # cowardly bail out until someone fixes the semantics of trying to # pass None to a C++ flag. See swig_flags.Init() for details on # this behavior. # TODO(olexiy): Users can directly call this method, bypassing all flags # validators (we don't have FlagValues here, so we can not check # validators). # The simplest solution I see is to make this method private. # Another approach would be to store reference to the corresponding # FlagValues with each flag, but this seems to be an overkill. if value is None and self.allow_override: raise DuplicateFlagCannotPropagateNoneToSwig(self.name) self.default = value self.Unparse() self.default_as_str = self.__GetParsedValueAsString(self.value) def Type(self): """Returns: a string that describes the type of this Flag.""" # NOTE: we use strings, and not the types.*Type constants because # our flags can have more exotic types, e.g., 'comma separated list # of strings', 'whitespace separated list of strings', etc. return self.parser.Type() def WriteInfoInXMLFormat(self, outfile, module_name, is_key=False, indent=''): """Writes common info about this flag, in XML format. This is information that is relevant to all flags (e.g., name, meaning, etc.). If you defined a flag that has some other pieces of info, then please override _WriteCustomInfoInXMLFormat. Please do NOT override this method. Args: outfile: File object we write to. module_name: A string, the name of the module that defines this flag. is_key: A boolean, True iff this flag is key for main module. indent: A string that is prepended to each generated line. """ outfile.write(indent + '<flag>\n') inner_indent = indent + ' ' if is_key: _WriteSimpleXMLElement(outfile, 'key', 'yes', inner_indent) _WriteSimpleXMLElement(outfile, 'file', module_name, inner_indent) # Print flag features that are relevant for all flags. _WriteSimpleXMLElement(outfile, 'name', self.name, inner_indent) if self.short_name: _WriteSimpleXMLElement(outfile, 'short_name', self.short_name, inner_indent) if self.help: _WriteSimpleXMLElement(outfile, 'meaning', self.help, inner_indent) # The default flag value can either be represented as a string like on the # command line, or as a Python object. We serialize this value in the # latter case in order to remain consistent. if self.serializer and not isinstance(self.default, str): default_serialized = self.serializer.Serialize(self.default) else: default_serialized = self.default _WriteSimpleXMLElement(outfile, 'default', default_serialized, inner_indent) _WriteSimpleXMLElement(outfile, 'current', self.value, inner_indent) _WriteSimpleXMLElement(outfile, 'type', self.Type(), inner_indent) # Print extra flag features this flag may have. self._WriteCustomInfoInXMLFormat(outfile, inner_indent) outfile.write(indent + '</flag>\n') def _WriteCustomInfoInXMLFormat(self, outfile, indent): """Writes extra info about this flag, in XML format. "Extra" means "not already printed by WriteInfoInXMLFormat above." Args: outfile: File object we write to. indent: A string that is prepended to each generated line. """ # Usually, the parser knows the extra details about the flag, so # we just forward the call to it. self.parser.WriteCustomInfoInXMLFormat(outfile, indent) # End of Flag definition class _ArgumentParserCache(type): """Metaclass used to cache and share argument parsers among flags.""" _instances = {} def __call__(mcs, *args, **kwargs): """Returns an instance of the argument parser cls. This method overrides behavior of the __new__ methods in all subclasses of ArgumentParser (inclusive). If an instance for mcs with the same set of arguments exists, this instance is returned, otherwise a new instance is created. If any keyword arguments are defined, or the values in args are not hashable, this method always returns a new instance of cls. Args: args: Positional initializer arguments. kwargs: Initializer keyword arguments. Returns: An instance of cls, shared or new. """ if kwargs: return type.__call__(mcs, *args, **kwargs) else: instances = mcs._instances key = (mcs,) + tuple(args) try: return instances[key] except KeyError: # No cache entry for key exists, create a new one. return instances.setdefault(key, type.__call__(mcs, *args)) except TypeError: # An object in args cannot be hashed, always return # a new instance. return type.__call__(mcs, *args) class ArgumentParser(object): """Base class used to parse and convert arguments. The Parse() method checks to make sure that the string argument is a legal value and convert it to a native type. If the value cannot be converted, it should throw a 'ValueError' exception with a human readable explanation of why the value is illegal. Subclasses should also define a syntactic_help string which may be presented to the user to describe the form of the legal values. Argument parser classes must be stateless, since instances are cached and shared between flags. Initializer arguments are allowed, but all member variables must be derived from initializer arguments only. """ __metaclass__ = _ArgumentParserCache syntactic_help = "" def Parse(self, argument): """Default implementation: always returns its argument unmodified.""" return argument def Type(self): return 'string' def WriteCustomInfoInXMLFormat(self, outfile, indent): pass class ArgumentSerializer: """Base class for generating string representations of a flag value.""" def Serialize(self, value): return str(value) class ListSerializer(ArgumentSerializer): def __init__(self, list_sep): self.list_sep = list_sep def Serialize(self, value): return self.list_sep.join([str(x) for x in value]) # Flags validators def RegisterValidator(flag_name, checker, message='Flag validation failed', flag_values=FLAGS): """Adds a constraint, which will be enforced during program execution. The constraint is validated when flags are initially parsed, and after each change of the corresponding flag's value. Args: flag_name: string, name of the flag to be checked. checker: method to validate the flag. input - value of the corresponding flag (string, boolean, etc. This value will be passed to checker by the library). See file's docstring for examples. output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise gflags_validators.Error(desired_error_message). message: error text to be shown to the user if checker returns False. If checker raises gflags_validators.Error, message from the raised Error will be shown. flag_values: FlagValues Raises: AttributeError: if flag_name is not registered as a valid flag name. """ flag_values.AddValidator(gflags_validators.SimpleValidator(flag_name, checker, message)) def MarkFlagAsRequired(flag_name, flag_values=FLAGS): """Ensure that flag is not None during program execution. Registers a flag validator, which will follow usual validator rules. Args: flag_name: string, name of the flag flag_values: FlagValues Raises: AttributeError: if flag_name is not registered as a valid flag name. """ RegisterValidator(flag_name, lambda value: value is not None, message='Flag --%s must be specified.' % flag_name, flag_values=flag_values) def _RegisterBoundsValidatorIfNeeded(parser, name, flag_values): """Enforce lower and upper bounds for numeric flags. Args: parser: NumericParser (either FloatParser or IntegerParser). Provides lower and upper bounds, and help text to display. name: string, name of the flag flag_values: FlagValues """ if parser.lower_bound is not None or parser.upper_bound is not None: def Checker(value): if value is not None and parser.IsOutsideBounds(value): message = '%s is not %s' % (value, parser.syntactic_help) raise gflags_validators.Error(message) return True RegisterValidator(name, Checker, flag_values=flag_values) # The DEFINE functions are explained in mode details in the module doc string. def DEFINE(parser, name, default, help, flag_values=FLAGS, serializer=None, **args): """Registers a generic Flag object. NOTE: in the docstrings of all DEFINE* functions, "registers" is short for "creates a new flag and registers it". Auxiliary function: clients should use the specialized DEFINE_<type> function instead. Args: parser: ArgumentParser that is used to parse the flag arguments. name: A string, the flag name. default: The default value of the flag. help: A help string. flag_values: FlagValues object the flag will be registered with. serializer: ArgumentSerializer that serializes the flag value. args: Dictionary with extra keyword args that are passes to the Flag __init__. """ DEFINE_flag(Flag(parser, serializer, name, default, help, **args), flag_values) def DEFINE_flag(flag, flag_values=FLAGS): """Registers a 'Flag' object with a 'FlagValues' object. By default, the global FLAGS 'FlagValue' object is used. Typical users will use one of the more specialized DEFINE_xxx functions, such as DEFINE_string or DEFINE_integer. But developers who need to create Flag objects themselves should use this function to register their flags. """ # copying the reference to flag_values prevents pychecker warnings fv = flag_values fv[flag.name] = flag # Tell flag_values who's defining the flag. if isinstance(flag_values, FlagValues): # Regarding the above isinstance test: some users pass funny # values of flag_values (e.g., {}) in order to avoid the flag # registration (in the past, there used to be a flag_values == # FLAGS test here) and redefine flags with the same name (e.g., # debug). To avoid breaking their code, we perform the # registration only if flag_values is a real FlagValues object. flag_values._RegisterFlagByModule(_GetCallingModule(), flag) def _InternalDeclareKeyFlags(flag_names, flag_values=FLAGS, key_flag_values=None): """Declares a flag as key for the calling module. Internal function. User code should call DECLARE_key_flag or ADOPT_module_key_flags instead. Args: flag_names: A list of strings that are names of already-registered Flag objects. flag_values: A FlagValues object that the flags listed in flag_names have registered with (the value of the flag_values argument from the DEFINE_* calls that defined those flags). This should almost never need to be overridden. key_flag_values: A FlagValues object that (among possibly many other things) keeps track of the key flags for each module. Default None means "same as flag_values". This should almost never need to be overridden. Raises: UnrecognizedFlagError: when we refer to a flag that was not defined yet. """ key_flag_values = key_flag_values or flag_values module = _GetCallingModule() for flag_name in flag_names: if flag_name not in flag_values: raise UnrecognizedFlagError(flag_name) flag = flag_values.FlagDict()[flag_name] key_flag_values._RegisterKeyFlagForModule(module, flag) def DECLARE_key_flag(flag_name, flag_values=FLAGS): """Declares one flag as key to the current module. Key flags are flags that are deemed really important for a module. They are important when listing help messages; e.g., if the --helpshort command-line flag is used, then only the key flags of the main module are listed (instead of all flags, as in the case of --help). Sample usage: flags.DECLARED_key_flag('flag_1') Args: flag_name: A string, the name of an already declared flag. (Redeclaring flags as key, including flags implicitly key because they were declared in this module, is a no-op.) flag_values: A FlagValues object. This should almost never need to be overridden. """ if flag_name in _SPECIAL_FLAGS: # Take care of the special flags, e.g., --flagfile, --undefok. # These flags are defined in _SPECIAL_FLAGS, and are treated # specially during flag parsing, taking precedence over the # user-defined flags. _InternalDeclareKeyFlags([flag_name], flag_values=_SPECIAL_FLAGS, key_flag_values=flag_values) return _InternalDeclareKeyFlags([flag_name], flag_values=flag_values) def ADOPT_module_key_flags(module, flag_values=FLAGS): """Declares that all flags key to a module are key to the current module. Args: module: A module object. flag_values: A FlagValues object. This should almost never need to be overridden. Raises: FlagsError: When given an argument that is a module name (a string), instead of a module object. """ # NOTE(salcianu): an even better test would be if not # isinstance(module, types.ModuleType) but I didn't want to import # types for such a tiny use. if isinstance(module, str): raise FlagsError('Received module name %s; expected a module object.' % module) _InternalDeclareKeyFlags( [f.name for f in flag_values._GetKeyFlagsForModule(module.__name__)], flag_values=flag_values) # If module is this flag module, take _SPECIAL_FLAGS into account. if module == _GetThisModuleObjectAndName()[0]: _InternalDeclareKeyFlags( # As we associate flags with _GetCallingModule(), the special # flags defined in this module are incorrectly registered with # a different module. So, we can't use _GetKeyFlagsForModule. # Instead, we take all flags from _SPECIAL_FLAGS (a private # FlagValues, where no other module should register flags). [f.name for f in _SPECIAL_FLAGS.FlagDict().values()], flag_values=_SPECIAL_FLAGS, key_flag_values=flag_values) # # STRING FLAGS # def DEFINE_string(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value can be any string.""" parser = ArgumentParser() serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) # # BOOLEAN FLAGS # # and the special HELP flags. class BooleanParser(ArgumentParser): """Parser of boolean values.""" def Convert(self, argument): """Converts the argument to a boolean; raise ValueError on errors.""" if type(argument) == str: if argument.lower() in ['true', 't', '1']: return True elif argument.lower() in ['false', 'f', '0']: return False bool_argument = bool(argument) if argument == bool_argument: # The argument is a valid boolean (True, False, 0, or 1), and not just # something that always converts to bool (list, string, int, etc.). return bool_argument raise ValueError('Non-boolean argument to boolean flag', argument) def Parse(self, argument): val = self.Convert(argument) return val def Type(self): return 'bool' class BooleanFlag(Flag): """Basic boolean flag. Boolean flags do not take any arguments, and their value is either True (1) or False (0). The false value is specified on the command line by prepending the word 'no' to either the long or the short flag name. For example, if a Boolean flag was created whose long name was 'update' and whose short name was 'x', then this flag could be explicitly unset through either --noupdate or --nox. """ def __init__(self, name, default, help, short_name=None, **args): p = BooleanParser() Flag.__init__(self, p, None, name, default, help, short_name, 1, **args) if not self.help: self.help = "a boolean value" def DEFINE_boolean(name, default, help, flag_values=FLAGS, **args): """Registers a boolean flag. Such a boolean flag does not take an argument. If a user wants to specify a false value explicitly, the long option beginning with 'no' must be used: i.e. --noflag This flag will have a value of None, True or False. None is possible if default=None and the user does not specify the flag on the command line. """ DEFINE_flag(BooleanFlag(name, default, help, **args), flag_values) # Match C++ API to unconfuse C++ people. DEFINE_bool = DEFINE_boolean class HelpFlag(BooleanFlag): """ HelpFlag is a special boolean flag that prints usage information and raises a SystemExit exception if it is ever found in the command line arguments. Note this is called with allow_override=1, so other apps can define their own --help flag, replacing this one, if they want. """ def __init__(self): BooleanFlag.__init__(self, "help", 0, "show this help", short_name="?", allow_override=1) def Parse(self, arg): if arg: doc = sys.modules["__main__"].__doc__ flags = str(FLAGS) print doc or ("\nUSAGE: %s [flags]\n" % sys.argv[0]) if flags: print "flags:" print flags sys.exit(1) class HelpXMLFlag(BooleanFlag): """Similar to HelpFlag, but generates output in XML format.""" def __init__(self): BooleanFlag.__init__(self, 'helpxml', False, 'like --help, but generates XML output', allow_override=1) def Parse(self, arg): if arg: FLAGS.WriteHelpInXMLFormat(sys.stdout) sys.exit(1) class HelpshortFlag(BooleanFlag): """ HelpshortFlag is a special boolean flag that prints usage information for the "main" module, and rasies a SystemExit exception if it is ever found in the command line arguments. Note this is called with allow_override=1, so other apps can define their own --helpshort flag, replacing this one, if they want. """ def __init__(self): BooleanFlag.__init__(self, "helpshort", 0, "show usage only for this module", allow_override=1) def Parse(self, arg): if arg: doc = sys.modules["__main__"].__doc__ flags = FLAGS.MainModuleHelp() print doc or ("\nUSAGE: %s [flags]\n" % sys.argv[0]) if flags: print "flags:" print flags sys.exit(1) # # Numeric parser - base class for Integer and Float parsers # class NumericParser(ArgumentParser): """Parser of numeric values. Parsed value may be bounded to a given upper and lower bound. """ def IsOutsideBounds(self, val): return ((self.lower_bound is not None and val < self.lower_bound) or (self.upper_bound is not None and val > self.upper_bound)) def Parse(self, argument): val = self.Convert(argument) if self.IsOutsideBounds(val): raise ValueError("%s is not %s" % (val, self.syntactic_help)) return val def WriteCustomInfoInXMLFormat(self, outfile, indent): if self.lower_bound is not None: _WriteSimpleXMLElement(outfile, 'lower_bound', self.lower_bound, indent) if self.upper_bound is not None: _WriteSimpleXMLElement(outfile, 'upper_bound', self.upper_bound, indent) def Convert(self, argument): """Default implementation: always returns its argument unmodified.""" return argument # End of Numeric Parser # # FLOAT FLAGS # class FloatParser(NumericParser): """Parser of floating point values. Parsed value may be bounded to a given upper and lower bound. """ number_article = "a" number_name = "number" syntactic_help = " ".join((number_article, number_name)) def __init__(self, lower_bound=None, upper_bound=None): super(FloatParser, self).__init__() self.lower_bound = lower_bound self.upper_bound = upper_bound sh = self.syntactic_help if lower_bound is not None and upper_bound is not None: sh = ("%s in the range [%s, %s]" % (sh, lower_bound, upper_bound)) elif lower_bound == 0: sh = "a non-negative %s" % self.number_name elif upper_bound == 0: sh = "a non-positive %s" % self.number_name elif upper_bound is not None: sh = "%s <= %s" % (self.number_name, upper_bound) elif lower_bound is not None: sh = "%s >= %s" % (self.number_name, lower_bound) self.syntactic_help = sh def Convert(self, argument): """Converts argument to a float; raises ValueError on errors.""" return float(argument) def Type(self): return 'float' # End of FloatParser def DEFINE_float(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value must be a float. If lower_bound or upper_bound are set, then this flag must be within the given range. """ parser = FloatParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) _RegisterBoundsValidatorIfNeeded(parser, name, flag_values=flag_values) # # INTEGER FLAGS # class IntegerParser(NumericParser): """Parser of an integer value. Parsed value may be bounded to a given upper and lower bound. """ number_article = "an" number_name = "integer" syntactic_help = " ".join((number_article, number_name)) def __init__(self, lower_bound=None, upper_bound=None): super(IntegerParser, self).__init__() self.lower_bound = lower_bound self.upper_bound = upper_bound sh = self.syntactic_help if lower_bound is not None and upper_bound is not None: sh = ("%s in the range [%s, %s]" % (sh, lower_bound, upper_bound)) elif lower_bound == 1: sh = "a positive %s" % self.number_name elif upper_bound == -1: sh = "a negative %s" % self.number_name elif lower_bound == 0: sh = "a non-negative %s" % self.number_name elif upper_bound == 0: sh = "a non-positive %s" % self.number_name elif upper_bound is not None: sh = "%s <= %s" % (self.number_name, upper_bound) elif lower_bound is not None: sh = "%s >= %s" % (self.number_name, lower_bound) self.syntactic_help = sh def Convert(self, argument): __pychecker__ = 'no-returnvalues' if type(argument) == str: base = 10 if len(argument) > 2 and argument[0] == "0" and argument[1] == "x": base = 16 try: return int(argument, base) # ValueError is thrown when argument is a string, and overflows an int. except ValueError: return long(argument, base) else: try: return int(argument) # OverflowError is thrown when argument is numeric, and overflows an int. except OverflowError: return long(argument) def Type(self): return 'int' def DEFINE_integer(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value must be an integer. If lower_bound, or upper_bound are set, then this flag must be within the given range. """ parser = IntegerParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) _RegisterBoundsValidatorIfNeeded(parser, name, flag_values=flag_values) # # ENUM FLAGS # class EnumParser(ArgumentParser): """Parser of a string enum value (a string value from a given set). If enum_values (see below) is not specified, any string is allowed. """ def __init__(self, enum_values=None): super(EnumParser, self).__init__() self.enum_values = enum_values def Parse(self, argument): if self.enum_values and argument not in self.enum_values: raise ValueError("value should be one of <%s>" % "|".join(self.enum_values)) return argument def Type(self): return 'string enum' class EnumFlag(Flag): """Basic enum flag; its value can be any string from list of enum_values.""" def __init__(self, name, default, help, enum_values=None, short_name=None, **args): enum_values = enum_values or [] p = EnumParser(enum_values) g = ArgumentSerializer() Flag.__init__(self, p, g, name, default, help, short_name, **args) if not self.help: self.help = "an enum string" self.help = "<%s>: %s" % ("|".join(enum_values), self.help) def _WriteCustomInfoInXMLFormat(self, outfile, indent): for enum_value in self.parser.enum_values: _WriteSimpleXMLElement(outfile, 'enum_value', enum_value, indent) def DEFINE_enum(name, default, enum_values, help, flag_values=FLAGS, **args): """Registers a flag whose value can be any string from enum_values.""" DEFINE_flag(EnumFlag(name, default, help, enum_values, ** args), flag_values) # # LIST FLAGS # class BaseListParser(ArgumentParser): """Base class for a parser of lists of strings. To extend, inherit from this class; from the subclass __init__, call BaseListParser.__init__(self, token, name) where token is a character used to tokenize, and name is a description of the separator. """ def __init__(self, token=None, name=None): assert name super(BaseListParser, self).__init__() self._token = token self._name = name self.syntactic_help = "a %s separated list" % self._name def Parse(self, argument): if isinstance(argument, list): return argument elif argument == '': return [] else: return [s.strip() for s in argument.split(self._token)] def Type(self): return '%s separated list of strings' % self._name class ListParser(BaseListParser): """Parser for a comma-separated list of strings.""" def __init__(self): BaseListParser.__init__(self, ',', 'comma') def WriteCustomInfoInXMLFormat(self, outfile, indent): BaseListParser.WriteCustomInfoInXMLFormat(self, outfile, indent) _WriteSimpleXMLElement(outfile, 'list_separator', repr(','), indent) class WhitespaceSeparatedListParser(BaseListParser): """Parser for a whitespace-separated list of strings.""" def __init__(self): BaseListParser.__init__(self, None, 'whitespace') def WriteCustomInfoInXMLFormat(self, outfile, indent): BaseListParser.WriteCustomInfoInXMLFormat(self, outfile, indent) separators = list(string.whitespace) separators.sort() for ws_char in string.whitespace: _WriteSimpleXMLElement(outfile, 'list_separator', repr(ws_char), indent) def DEFINE_list(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value is a comma-separated list of strings.""" parser = ListParser() serializer = ListSerializer(',') DEFINE(parser, name, default, help, flag_values, serializer, **args) def DEFINE_spaceseplist(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value is a whitespace-separated list of strings. Any whitespace can be used as a separator. """ parser = WhitespaceSeparatedListParser() serializer = ListSerializer(' ') DEFINE(parser, name, default, help, flag_values, serializer, **args) # # MULTI FLAGS # class MultiFlag(Flag): """A flag that can appear multiple time on the command-line. The value of such a flag is a list that contains the individual values from all the appearances of that flag on the command-line. See the __doc__ for Flag for most behavior of this class. Only differences in behavior are described here: * The default value may be either a single value or a list of values. A single value is interpreted as the [value] singleton list. * The value of the flag is always a list, even if the option was only supplied once, and even if the default value is a single value """ def __init__(self, *args, **kwargs): Flag.__init__(self, *args, **kwargs) self.help += ';\n repeat this option to specify a list of values' def Parse(self, arguments): """Parses one or more arguments with the installed parser. Args: arguments: a single argument or a list of arguments (typically a list of default values); a single argument is converted internally into a list containing one item. """ if not isinstance(arguments, list): # Default value may be a list of values. Most other arguments # will not be, so convert them into a single-item list to make # processing simpler below. arguments = [arguments] if self.present: # keep a backup reference to list of previously supplied option values values = self.value else: # "erase" the defaults with an empty list values = [] for item in arguments: # have Flag superclass parse argument, overwriting self.value reference Flag.Parse(self, item) # also increments self.present values.append(self.value) # put list of option values back in the 'value' attribute self.value = values def Serialize(self): if not self.serializer: raise FlagsError("Serializer not present for flag %s" % self.name) if self.value is None: return '' s = '' multi_value = self.value for self.value in multi_value: if s: s += ' ' s += Flag.Serialize(self) self.value = multi_value return s def Type(self): return 'multi ' + self.parser.Type() def DEFINE_multi(parser, serializer, name, default, help, flag_values=FLAGS, **args): """Registers a generic MultiFlag that parses its args with a given parser. Auxiliary function. Normal users should NOT use it directly. Developers who need to create their own 'Parser' classes for options which can appear multiple times can call this module function to register their flags. """ DEFINE_flag(MultiFlag(parser, serializer, name, default, help, **args), flag_values) def DEFINE_multistring(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value can be a list of any strings. Use the flag on the command line multiple times to place multiple string values into the list. The 'default' may be a single string (which will be converted into a single-element list) or a list of strings. """ parser = ArgumentParser() serializer = ArgumentSerializer() DEFINE_multi(parser, serializer, name, default, help, flag_values, **args) def DEFINE_multi_int(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value can be a list of arbitrary integers. Use the flag on the command line multiple times to place multiple integer values into the list. The 'default' may be a single integer (which will be converted into a single-element list) or a list of integers. """ parser = IntegerParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE_multi(parser, serializer, name, default, help, flag_values, **args) # Now register the flags that we want to exist in all applications. # These are all defined with allow_override=1, so user-apps can use # these flagnames for their own purposes, if they want. DEFINE_flag(HelpFlag()) DEFINE_flag(HelpshortFlag()) DEFINE_flag(HelpXMLFlag()) # Define special flags here so that help may be generated for them. # NOTE: Please do NOT use _SPECIAL_FLAGS from outside this module. _SPECIAL_FLAGS = FlagValues() DEFINE_string( 'flagfile', "", "Insert flag definitions from the given file into the command line.", _SPECIAL_FLAGS) DEFINE_string( 'undefok', "", "comma-separated list of flag names that it is okay to specify " "on the command line even if the program does not define a flag " "with that name. IMPORTANT: flags in this list that have " "arguments MUST use the --flag=value format.", _SPECIAL_FLAGS)
Python
# Copyright 2010 Google Inc. All Rights Reserved. """Classes to encapsulate a single HTTP request. The classes implement a command pattern, with every object supporting an execute() method that does the actuall HTTP request. """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' __all__ = [ 'HttpRequest', 'RequestMockBuilder', 'HttpMock' 'set_user_agent', 'tunnel_patch' ] import httplib2 import os from model import JsonModel from errors import HttpError from anyjson import simplejson class HttpRequest(object): """Encapsulates a single HTTP request. """ def __init__(self, http, postproc, uri, method='GET', body=None, headers=None, methodId=None): """Constructor for an HttpRequest. Args: http: httplib2.Http, the transport object to use to make a request postproc: callable, called on the HTTP response and content to transform it into a data object before returning, or raising an exception on an error. uri: string, the absolute URI to send the request to method: string, the HTTP method to use body: string, the request body of the HTTP request headers: dict, the HTTP request headers methodId: string, a unique identifier for the API method being called. """ self.uri = uri self.method = method self.body = body self.headers = headers or {} self.http = http self.postproc = postproc def execute(self, http=None): """Execute the request. Args: http: httplib2.Http, an http object to be used in place of the one the HttpRequest request object was constructed with. Returns: A deserialized object model of the response body as determined by the postproc. Raises: apiclient.errors.HttpError if the response was not a 2xx. httplib2.Error if a transport error has occured. """ if http is None: http = self.http resp, content = http.request(self.uri, self.method, body=self.body, headers=self.headers) if resp.status >= 300: raise HttpError(resp, content, self.uri) return self.postproc(resp, content) class HttpRequestMock(object): """Mock of HttpRequest. Do not construct directly, instead use RequestMockBuilder. """ def __init__(self, resp, content, postproc): """Constructor for HttpRequestMock Args: resp: httplib2.Response, the response to emulate coming from the request content: string, the response body postproc: callable, the post processing function usually supplied by the model class. See model.JsonModel.response() as an example. """ self.resp = resp self.content = content self.postproc = postproc if resp is None: self.resp = httplib2.Response({'status': 200, 'reason': 'OK'}) if 'reason' in self.resp: self.resp.reason = self.resp['reason'] def execute(self, http=None): """Execute the request. Same behavior as HttpRequest.execute(), but the response is mocked and not really from an HTTP request/response. """ return self.postproc(self.resp, self.content) class RequestMockBuilder(object): """A simple mock of HttpRequest Pass in a dictionary to the constructor that maps request methodIds to tuples of (httplib2.Response, content) that should be returned when that method is called. None may also be passed in for the httplib2.Response, in which case a 200 OK response will be generated. Example: response = '{"data": {"id": "tag:google.c...' requestBuilder = RequestMockBuilder( { 'chili.activities.get': (None, response), } ) apiclient.discovery.build("buzz", "v1", requestBuilder=requestBuilder) Methods that you do not supply a response for will return a 200 OK with an empty string as the response content. The methodId is taken from the rpcName in the discovery document. For more details see the project wiki. """ def __init__(self, responses): """Constructor for RequestMockBuilder The constructed object should be a callable object that can replace the class HttpResponse. responses - A dictionary that maps methodIds into tuples of (httplib2.Response, content). The methodId comes from the 'rpcName' field in the discovery document. """ self.responses = responses def __call__(self, http, postproc, uri, method='GET', body=None, headers=None, methodId=None): """Implements the callable interface that discovery.build() expects of requestBuilder, which is to build an object compatible with HttpRequest.execute(). See that method for the description of the parameters and the expected response. """ if methodId in self.responses: resp, content = self.responses[methodId] return HttpRequestMock(resp, content, postproc) else: model = JsonModel(False) return HttpRequestMock(None, '{}', model.response) class HttpMock(object): """Mock of httplib2.Http""" def __init__(self, filename, headers=None): """ Args: filename: string, absolute filename to read response from headers: dict, header to return with response """ if headers is None: headers = {'status': '200 OK'} f = file(filename, 'r') self.data = f.read() f.close() self.headers = headers def request(self, uri, method='GET', body=None, headers=None, redirections=1, connection_type=None): return httplib2.Response(self.headers), self.data class HttpMockSequence(object): """Mock of httplib2.Http Mocks a sequence of calls to request returning different responses for each call. Create an instance initialized with the desired response headers and content and then use as if an httplib2.Http instance. http = HttpMockSequence([ ({'status': '401'}, ''), ({'status': '200'}, '{"access_token":"1/3w","expires_in":3600}'), ({'status': '200'}, 'echo_request_headers'), ]) resp, content = http.request("http://examples.com") There are special values you can pass in for content to trigger behavours that are helpful in testing. 'echo_request_headers' means return the request headers in the response body 'echo_request_headers_as_json' means return the request headers in the response body 'echo_request_body' means return the request body in the response body """ def __init__(self, iterable): """ Args: iterable: iterable, a sequence of pairs of (headers, body) """ self._iterable = iterable def request(self, uri, method='GET', body=None, headers=None, redirections=1, connection_type=None): resp, content = self._iterable.pop(0) if content == 'echo_request_headers': content = headers elif content == 'echo_request_headers_as_json': content = simplejson.dumps(headers) elif content == 'echo_request_body': content = body return httplib2.Response(resp), content def set_user_agent(http, user_agent): """Set the user-agent on every request. Args: http - An instance of httplib2.Http or something that acts like it. user_agent: string, the value for the user-agent header. Returns: A modified instance of http that was passed in. Example: h = httplib2.Http() h = set_user_agent(h, "my-app-name/6.0") Most of the time the user-agent will be set doing auth, this is for the rare cases where you are accessing an unauthenticated endpoint. """ request_orig = http.request # The closure that will replace 'httplib2.Http.request'. def new_request(uri, method='GET', body=None, headers=None, redirections=httplib2.DEFAULT_MAX_REDIRECTS, connection_type=None): """Modify the request headers to add the user-agent.""" if headers is None: headers = {} if 'user-agent' in headers: headers['user-agent'] = user_agent + ' ' + headers['user-agent'] else: headers['user-agent'] = user_agent resp, content = request_orig(uri, method, body, headers, redirections, connection_type) return resp, content http.request = new_request return http def tunnel_patch(http): """Tunnel PATCH requests over POST. Args: http - An instance of httplib2.Http or something that acts like it. Returns: A modified instance of http that was passed in. Example: h = httplib2.Http() h = tunnel_patch(h, "my-app-name/6.0") Useful if you are running on a platform that doesn't support PATCH. Apply this last if you are using OAuth 1.0, as changing the method will result in a different signature. """ request_orig = http.request # The closure that will replace 'httplib2.Http.request'. def new_request(uri, method='GET', body=None, headers=None, redirections=httplib2.DEFAULT_MAX_REDIRECTS, connection_type=None): """Modify the request headers to add the user-agent.""" if headers is None: headers = {} if method == 'PATCH': if 'oauth_token' in headers.get('authorization', ''): logging.warning( 'OAuth 1.0 request made with Credentials after tunnel_patch.') headers['x-http-method-override'] = "PATCH" method = 'POST' resp, content = request_orig(uri, method, body, headers, redirections, connection_type) return resp, content http.request = new_request return http
Python
# Copyright 2010 Google Inc. All Rights Reserved. """Utilities for OAuth. Utilities for making it easier to work with OAuth. """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' import copy import httplib2 import logging import oauth2 as oauth import urllib import urlparse from anyjson import simplejson try: from urlparse import parse_qsl except ImportError: from cgi import parse_qsl class Error(Exception): """Base error for this module.""" pass class RequestError(Error): """Error occurred during request.""" pass class MissingParameter(Error): pass class CredentialsInvalidError(Error): pass def _abstract(): raise NotImplementedError('You need to override this function') def _oauth_uri(name, discovery, params): """Look up the OAuth URI from the discovery document and add query parameters based on params. name - The name of the OAuth URI to lookup, one of 'request', 'access', or 'authorize'. discovery - Portion of discovery document the describes the OAuth endpoints. params - Dictionary that is used to form the query parameters for the specified URI. """ if name not in ['request', 'access', 'authorize']: raise KeyError(name) keys = discovery[name]['parameters'].keys() query = {} for key in keys: if key in params: query[key] = params[key] return discovery[name]['url'] + '?' + urllib.urlencode(query) class Credentials(object): """Base class for all Credentials objects. Subclasses must define an authorize() method that applies the credentials to an HTTP transport. """ def authorize(self, http): """Take an httplib2.Http instance (or equivalent) and authorizes it for the set of credentials, usually by replacing http.request() with a method that adds in the appropriate headers and then delegates to the original Http.request() method. """ _abstract() class Flow(object): """Base class for all Flow objects.""" pass class Storage(object): """Base class for all Storage objects. Store and retrieve a single credential. """ def get(self): """Retrieve credential. Returns: apiclient.oauth.Credentials """ _abstract() def put(self, credentials): """Write a credential. Args: credentials: Credentials, the credentials to store. """ _abstract() class OAuthCredentials(Credentials): """Credentials object for OAuth 1.0a """ def __init__(self, consumer, token, user_agent): """ consumer - An instance of oauth.Consumer. token - An instance of oauth.Token constructed with the access token and secret. user_agent - The HTTP User-Agent to provide for this application. """ self.consumer = consumer self.token = token self.user_agent = user_agent self.store = None # True if the credentials have been revoked self._invalid = False @property def invalid(self): """True if the credentials are invalid, such as being revoked.""" return getattr(self, "_invalid", False) def set_store(self, store): """Set the storage for the credential. Args: store: callable, a callable that when passed a Credential will store the credential back to where it came from. This is needed to store the latest access_token if it has been revoked. """ self.store = store def __getstate__(self): """Trim the state down to something that can be pickled.""" d = copy.copy(self.__dict__) del d['store'] return d def __setstate__(self, state): """Reconstitute the state of the object from being pickled.""" self.__dict__.update(state) self.store = None def authorize(self, http): """ Args: http - An instance of httplib2.Http or something that acts like it. Returns: A modified instance of http that was passed in. Example: h = httplib2.Http() h = credentials.authorize(h) You can't create a new OAuth subclass of httplib2.Authenication because it never gets passed the absolute URI, which is needed for signing. So instead we have to overload 'request' with a closure that adds in the Authorization header and then calls the original version of 'request()'. """ request_orig = http.request signer = oauth.SignatureMethod_HMAC_SHA1() # The closure that will replace 'httplib2.Http.request'. def new_request(uri, method='GET', body=None, headers=None, redirections=httplib2.DEFAULT_MAX_REDIRECTS, connection_type=None): """Modify the request headers to add the appropriate Authorization header.""" response_code = 302 http.follow_redirects = False while response_code in [301, 302]: req = oauth.Request.from_consumer_and_token( self.consumer, self.token, http_method=method, http_url=uri) req.sign_request(signer, self.consumer, self.token) if headers is None: headers = {} headers.update(req.to_header()) if 'user-agent' in headers: headers['user-agent'] = self.user_agent + ' ' + headers['user-agent'] else: headers['user-agent'] = self.user_agent resp, content = request_orig(uri, method, body, headers, redirections, connection_type) response_code = resp.status if response_code in [301, 302]: uri = resp['location'] # Update the stored credential if it becomes invalid. if response_code == 401: logging.info('Access token no longer valid: %s' % content) self._invalid = True if self.store is not None: self.store(self) raise CredentialsInvalidError("Credentials are no longer valid.") return resp, content http.request = new_request return http class FlowThreeLegged(Flow): """Does the Three Legged Dance for OAuth 1.0a. """ def __init__(self, discovery, consumer_key, consumer_secret, user_agent, **kwargs): """ discovery - Section of the API discovery document that describes the OAuth endpoints. consumer_key - OAuth consumer key consumer_secret - OAuth consumer secret user_agent - The HTTP User-Agent that identifies the application. **kwargs - The keyword arguments are all optional and required parameters for the OAuth calls. """ self.discovery = discovery self.consumer_key = consumer_key self.consumer_secret = consumer_secret self.user_agent = user_agent self.params = kwargs self.request_token = {} required = {} for uriinfo in discovery.itervalues(): for name, value in uriinfo['parameters'].iteritems(): if value['required'] and not name.startswith('oauth_'): required[name] = 1 for key in required.iterkeys(): if key not in self.params: raise MissingParameter('Required parameter %s not supplied' % key) def step1_get_authorize_url(self, oauth_callback='oob'): """Returns a URI to redirect to the provider. oauth_callback - Either the string 'oob' for a non-web-based application, or a URI that handles the callback from the authorization server. If oauth_callback is 'oob' then pass in the generated verification code to step2_exchange, otherwise pass in the query parameters received at the callback uri to step2_exchange. """ consumer = oauth.Consumer(self.consumer_key, self.consumer_secret) client = oauth.Client(consumer) headers = { 'user-agent': self.user_agent, 'content-type': 'application/x-www-form-urlencoded' } body = urllib.urlencode({'oauth_callback': oauth_callback}) uri = _oauth_uri('request', self.discovery, self.params) resp, content = client.request(uri, 'POST', headers=headers, body=body) if resp['status'] != '200': logging.error('Failed to retrieve temporary authorization: %s', content) raise RequestError('Invalid response %s.' % resp['status']) self.request_token = dict(parse_qsl(content)) auth_params = copy.copy(self.params) auth_params['oauth_token'] = self.request_token['oauth_token'] return _oauth_uri('authorize', self.discovery, auth_params) def step2_exchange(self, verifier): """Exhanges an authorized request token for OAuthCredentials. Args: verifier: string, dict - either the verifier token, or a dictionary of the query parameters to the callback, which contains the oauth_verifier. Returns: The Credentials object. """ if not (isinstance(verifier, str) or isinstance(verifier, unicode)): verifier = verifier['oauth_verifier'] token = oauth.Token( self.request_token['oauth_token'], self.request_token['oauth_token_secret']) token.set_verifier(verifier) consumer = oauth.Consumer(self.consumer_key, self.consumer_secret) client = oauth.Client(consumer, token) headers = { 'user-agent': self.user_agent, 'content-type': 'application/x-www-form-urlencoded' } uri = _oauth_uri('access', self.discovery, self.params) resp, content = client.request(uri, 'POST', headers=headers) if resp['status'] != '200': logging.error('Failed to retrieve access token: %s', content) raise RequestError('Invalid response %s.' % resp['status']) oauth_params = dict(parse_qsl(content)) token = oauth.Token( oauth_params['oauth_token'], oauth_params['oauth_token_secret']) return OAuthCredentials(consumer, token, self.user_agent)
Python
#!/usr/bin/python2.4 # # Copyright 2010 Google Inc. All Rights Reserved. """Model objects for requests and responses. Each API may support one or more serializations, such as JSON, Atom, etc. The model classes are responsible for converting between the wire format and the Python object representation. """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' import gflags import logging import urllib from anyjson import simplejson from errors import HttpError FLAGS = gflags.FLAGS gflags.DEFINE_boolean('dump_request_response', False, 'Dump all http server requests and responses. ' 'Must use apiclient.model.LoggingJsonModel as ' 'the model.' ) def _abstract(): raise NotImplementedError('You need to override this function') class Model(object): """Model base class. All Model classes should implement this interface. The Model serializes and de-serializes between a wire format such as JSON and a Python object representation. """ def request(self, headers, path_params, query_params, body_value): """Updates outgoing requests with a deserialized body. Args: headers: dict, request headers path_params: dict, parameters that appear in the request path query_params: dict, parameters that appear in the query body_value: object, the request body as a Python object, which must be serializable. Returns: A tuple of (headers, path_params, query, body) headers: dict, request headers path_params: dict, parameters that appear in the request path query: string, query part of the request URI body: string, the body serialized in the desired wire format. """ _abstract() def response(self, resp, content): """Convert the response wire format into a Python object. Args: resp: httplib2.Response, the HTTP response headers and status content: string, the body of the HTTP response Returns: The body de-serialized as a Python object. Raises: apiclient.errors.HttpError if a non 2xx response is received. """ _abstract() class JsonModel(Model): """Model class for JSON. Serializes and de-serializes between JSON and the Python object representation of HTTP request and response bodies. """ def __init__(self, data_wrapper=False): """Construct a JsonModel Args: data_wrapper: boolean, wrap requests and responses in a data wrapper """ self._data_wrapper = data_wrapper def request(self, headers, path_params, query_params, body_value): """Updates outgoing requests with JSON bodies. Args: headers: dict, request headers path_params: dict, parameters that appear in the request path query_params: dict, parameters that appear in the query body_value: object, the request body as a Python object, which must be serializable by simplejson. Returns: A tuple of (headers, path_params, query, body) headers: dict, request headers path_params: dict, parameters that appear in the request path query: string, query part of the request URI body: string, the body serialized as JSON """ query = self._build_query(query_params) headers['accept'] = 'application/json' headers['accept-encoding'] = 'gzip, deflate' if 'user-agent' in headers: headers['user-agent'] += ' ' else: headers['user-agent'] = '' headers['user-agent'] += 'google-api-python-client/1.0' if (isinstance(body_value, dict) and 'data' not in body_value and self._data_wrapper): body_value = {'data': body_value} if body_value is not None: headers['content-type'] = 'application/json' body_value = simplejson.dumps(body_value) return (headers, path_params, query, body_value) def _build_query(self, params): """Builds a query string. Args: params: dict, the query parameters Returns: The query parameters properly encoded into an HTTP URI query string. """ params.update({'alt': 'json'}) astuples = [] for key, value in params.iteritems(): if type(value) == type([]): for x in value: x = x.encode('utf-8') astuples.append((key, x)) else: if getattr(value, 'encode', False) and callable(value.encode): value = value.encode('utf-8') astuples.append((key, value)) return '?' + urllib.urlencode(astuples) def response(self, resp, content): """Convert the response wire format into a Python object. Args: resp: httplib2.Response, the HTTP response headers and status content: string, the body of the HTTP response Returns: The body de-serialized as a Python object. Raises: apiclient.errors.HttpError if a non 2xx response is received. """ # Error handling is TBD, for example, do we retry # for some operation/error combinations? if resp.status < 300: if resp.status == 204: # A 204: No Content response should be treated differently # to all the other success states return simplejson.loads('{}') body = simplejson.loads(content) if isinstance(body, dict) and 'data' in body: body = body['data'] return body else: logging.debug('Content from bad request was: %s' % content) raise HttpError(resp, content) class LoggingJsonModel(JsonModel): """A printable JsonModel class that supports logging response info.""" def response(self, resp, content): """An overloaded response method that will output debug info if requested. Args: resp: An httplib2.Response object. content: A string representing the response body. Returns: The body de-serialized as a Python object. """ if FLAGS.dump_request_response: logging.info('--response-start--') for h, v in resp.iteritems(): logging.info('%s: %s', h, v) if content: logging.info(content) logging.info('--response-end--') return super(LoggingJsonModel, self).response( resp, content) def request(self, headers, path_params, query_params, body_value): """An overloaded request method that will output debug info if requested. Args: headers: dict, request headers path_params: dict, parameters that appear in the request path query_params: dict, parameters that appear in the query body_value: object, the request body as a Python object, which must be serializable by simplejson. Returns: A tuple of (headers, path_params, query, body) headers: dict, request headers path_params: dict, parameters that appear in the request path query: string, query part of the request URI body: string, the body serialized as JSON """ (headers, path_params, query, body) = super( LoggingJsonModel, self).request( headers, path_params, query_params, body_value) if FLAGS.dump_request_response: logging.info('--request-start--') logging.info('-headers-start-') for h, v in headers.iteritems(): logging.info('%s: %s', h, v) logging.info('-headers-end-') logging.info('-path-parameters-start-') for h, v in path_params.iteritems(): logging.info('%s: %s', h, v) logging.info('-path-parameters-end-') logging.info('body: %s', body) logging.info('query: %s', query) logging.info('--request-end--') return (headers, path_params, query, body)
Python
# Copyright (C) 2010 Google Inc. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. """Client for discovery based APIs A client library for Google's discovery based APIs. """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' __all__ = [ 'build', 'build_from_document' ] import httplib2 import logging import os import re import uritemplate import urllib import urlparse try: from urlparse import parse_qsl except ImportError: from cgi import parse_qsl from http import HttpRequest from anyjson import simplejson from model import JsonModel from errors import UnknownLinkType from errors import HttpError from errors import InvalidJsonError URITEMPLATE = re.compile('{[^}]*}') VARNAME = re.compile('[a-zA-Z0-9_-]+') DISCOVERY_URI = ('https://www.googleapis.com/discovery/v0.3/describe/' '{api}/{apiVersion}') DEFAULT_METHOD_DOC = 'A description of how to use this function' # Query parameters that work, but don't appear in discovery STACK_QUERY_PARAMETERS = ['trace', 'fields', 'pp', 'prettyPrint', 'userIp', 'strict'] def key2param(key): """Converts key names into parameter names. For example, converting "max-results" -> "max_results" """ result = [] key = list(key) if not key[0].isalpha(): result.append('x') for c in key: if c.isalnum(): result.append(c) else: result.append('_') return ''.join(result) def build(serviceName, version, http=None, discoveryServiceUrl=DISCOVERY_URI, developerKey=None, model=None, requestBuilder=HttpRequest): """Construct a Resource for interacting with an API. Construct a Resource object for interacting with an API. The serviceName and version are the names from the Discovery service. Args: serviceName: string, name of the service version: string, the version of the service discoveryServiceUrl: string, a URI Template that points to the location of the discovery service. It should have two parameters {api} and {apiVersion} that when filled in produce an absolute URI to the discovery document for that service. developerKey: string, key obtained from https://code.google.com/apis/console model: apiclient.Model, converts to and from the wire format requestBuilder: apiclient.http.HttpRequest, encapsulator for an HTTP request Returns: A Resource object with methods for interacting with the service. """ params = { 'api': serviceName, 'apiVersion': version } if http is None: http = httplib2.Http() requested_url = uritemplate.expand(discoveryServiceUrl, params) logging.info('URL being requested: %s' % requested_url) resp, content = http.request(requested_url) if resp.status > 400: raise HttpError(resp, content, requested_url) try: service = simplejson.loads(content) except ValueError, e: logging.error('Failed to parse as JSON: ' + content) raise InvalidJsonError() fn = os.path.join(os.path.dirname(__file__), 'contrib', serviceName, 'future.json') try: f = file(fn, 'r') future = f.read() f.close() except IOError: future = None return build_from_document(content, discoveryServiceUrl, future, http, developerKey, model, requestBuilder) def build_from_document( service, base, future=None, http=None, developerKey=None, model=None, requestBuilder=HttpRequest): """Create a Resource for interacting with an API. Same as `build()`, but constructs the Resource object from a discovery document that is it given, as opposed to retrieving one over HTTP. Args: service: string, discovery document base: string, base URI for all HTTP requests, usually the discovery URI future: string, discovery document with future capabilities auth_discovery: dict, information about the authentication the API supports http: httplib2.Http, An instance of httplib2.Http or something that acts like it that HTTP requests will be made through. developerKey: string, Key for controlling API usage, generated from the API Console. model: Model class instance that serializes and de-serializes requests and responses. requestBuilder: Takes an http request and packages it up to be executed. Returns: A Resource object with methods for interacting with the service. """ service = simplejson.loads(service) base = urlparse.urljoin(base, service['restBasePath']) if future: future = simplejson.loads(future) auth_discovery = future.get('auth', {}) else: future = {} auth_discovery = {} if model is None: features = service.get('features', []) model = JsonModel('dataWrapper' in features) resource = createResource(http, base, model, requestBuilder, developerKey, service, future) def auth_method(): """Discovery information about the authentication the API uses.""" return auth_discovery setattr(resource, 'auth_discovery', auth_method) return resource def _cast(value, schema_type): """Convert value to a string based on JSON Schema type. See http://tools.ietf.org/html/draft-zyp-json-schema-03 for more details on JSON Schema. Args: value: any, the value to convert schema_type: string, the type that value should be interpreted as Returns: A string representation of 'value' based on the schema_type. """ if schema_type == 'string': if type(value) == type('') or type(value) == type(u''): return value else: return str(value) elif schema_type == 'integer': return str(int(value)) elif schema_type == 'number': return str(float(value)) elif schema_type == 'boolean': return str(bool(value)).lower() else: if type(value) == type('') or type(value) == type(u''): return value else: return str(value) def createResource(http, baseUrl, model, requestBuilder, developerKey, resourceDesc, futureDesc): class Resource(object): """A class for interacting with a resource.""" def __init__(self): self._http = http self._baseUrl = baseUrl self._model = model self._developerKey = developerKey self._requestBuilder = requestBuilder def createMethod(theclass, methodName, methodDesc, futureDesc): pathUrl = methodDesc['restPath'] httpMethod = methodDesc['httpMethod'] methodId = methodDesc['rpcMethod'] if 'parameters' not in methodDesc: methodDesc['parameters'] = {} for name in STACK_QUERY_PARAMETERS: methodDesc['parameters'][name] = { 'type': 'string', 'restParameterType': 'query' } if httpMethod in ['PUT', 'POST', 'PATCH']: methodDesc['parameters']['body'] = { 'description': 'The request body.', 'type': 'object', 'required': True, } argmap = {} # Map from method parameter name to query parameter name required_params = [] # Required parameters repeated_params = [] # Repeated parameters pattern_params = {} # Parameters that must match a regex query_params = [] # Parameters that will be used in the query string path_params = {} # Parameters that will be used in the base URL param_type = {} # The type of the parameter enum_params = {} # Allowable enumeration values for each parameter if 'parameters' in methodDesc: for arg, desc in methodDesc['parameters'].iteritems(): param = key2param(arg) argmap[param] = arg if desc.get('pattern', ''): pattern_params[param] = desc['pattern'] if desc.get('enum', ''): enum_params[param] = desc['enum'] if desc.get('required', False): required_params.append(param) if desc.get('repeated', False): repeated_params.append(param) if desc.get('restParameterType') == 'query': query_params.append(param) if desc.get('restParameterType') == 'path': path_params[param] = param param_type[param] = desc.get('type', 'string') for match in URITEMPLATE.finditer(pathUrl): for namematch in VARNAME.finditer(match.group(0)): name = key2param(namematch.group(0)) path_params[name] = name if name in query_params: query_params.remove(name) def method(self, **kwargs): for name in kwargs.iterkeys(): if name not in argmap: raise TypeError('Got an unexpected keyword argument "%s"' % name) for name in required_params: if name not in kwargs: raise TypeError('Missing required parameter "%s"' % name) for name, regex in pattern_params.iteritems(): if name in kwargs: if re.match(regex, kwargs[name]) is None: raise TypeError( 'Parameter "%s" value "%s" does not match the pattern "%s"' % (name, kwargs[name], regex)) for name, enums in enum_params.iteritems(): if name in kwargs: if kwargs[name] not in enums: raise TypeError( 'Parameter "%s" value "%s" is not an allowed value in "%s"' % (name, kwargs[name], str(enums))) actual_query_params = {} actual_path_params = {} for key, value in kwargs.iteritems(): to_type = param_type.get(key, 'string') # For repeated parameters we cast each member of the list. if key in repeated_params and type(value) == type([]): cast_value = [_cast(x, to_type) for x in value] else: cast_value = _cast(value, to_type) if key in query_params: actual_query_params[argmap[key]] = cast_value if key in path_params: actual_path_params[argmap[key]] = cast_value body_value = kwargs.get('body', None) if self._developerKey: actual_query_params['key'] = self._developerKey headers = {} headers, params, query, body = self._model.request(headers, actual_path_params, actual_query_params, body_value) # TODO(ade) This exists to fix a bug in V1 of the Buzz discovery # document. Base URLs should not contain any path elements. If they do # then urlparse.urljoin will strip them out This results in an incorrect # URL which returns a 404 url_result = urlparse.urlsplit(self._baseUrl) new_base_url = url_result[0] + '://' + url_result[1] expanded_url = uritemplate.expand(pathUrl, params) url = urlparse.urljoin(self._baseUrl, url_result[2] + expanded_url + query) logging.info('URL being requested: %s' % url) return self._requestBuilder(self._http, self._model.response, url, method=httpMethod, body=body, headers=headers, methodId=methodId) docs = [methodDesc.get('description', DEFAULT_METHOD_DOC), '\n\n'] if len(argmap) > 0: docs.append('Args:\n') for arg in argmap.iterkeys(): if arg in STACK_QUERY_PARAMETERS: continue repeated = '' if arg in repeated_params: repeated = ' (repeated)' required = '' if arg in required_params: required = ' (required)' paramdesc = methodDesc['parameters'][argmap[arg]] paramdoc = paramdesc.get('description', 'A parameter') paramtype = paramdesc.get('type', 'string') docs.append(' %s: %s, %s%s%s\n' % (arg, paramtype, paramdoc, required, repeated)) enum = paramdesc.get('enum', []) enumDesc = paramdesc.get('enumDescriptions', []) if enum and enumDesc: docs.append(' Allowed values\n') for (name, desc) in zip(enum, enumDesc): docs.append(' %s - %s\n' % (name, desc)) setattr(method, '__doc__', ''.join(docs)) setattr(theclass, methodName, method) def createNextMethod(theclass, methodName, methodDesc, futureDesc): methodId = methodDesc['rpcMethod'] + '.next' def methodNext(self, previous): """ Takes a single argument, 'body', which is the results from the last call, and returns the next set of items in the collection. Returns None if there are no more items in the collection. """ if futureDesc['type'] != 'uri': raise UnknownLinkType(futureDesc['type']) try: p = previous for key in futureDesc['location']: p = p[key] url = p except (KeyError, TypeError): return None if self._developerKey: parsed = list(urlparse.urlparse(url)) q = parse_qsl(parsed[4]) q.append(('key', self._developerKey)) parsed[4] = urllib.urlencode(q) url = urlparse.urlunparse(parsed) headers = {} headers, params, query, body = self._model.request(headers, {}, {}, None) logging.info('URL being requested: %s' % url) resp, content = self._http.request(url, method='GET', headers=headers) return self._requestBuilder(self._http, self._model.response, url, method='GET', headers=headers, methodId=methodId) setattr(theclass, methodName, methodNext) # Add basic methods to Resource if 'methods' in resourceDesc: for methodName, methodDesc in resourceDesc['methods'].iteritems(): if futureDesc: future = futureDesc['methods'].get(methodName, {}) else: future = None createMethod(Resource, methodName, methodDesc, future) # Add in nested resources if 'resources' in resourceDesc: def createResourceMethod(theclass, methodName, methodDesc, futureDesc): def methodResource(self): return createResource(self._http, self._baseUrl, self._model, self._requestBuilder, self._developerKey, methodDesc, futureDesc) setattr(methodResource, '__doc__', 'A collection resource.') setattr(methodResource, '__is_resource__', True) setattr(theclass, methodName, methodResource) for methodName, methodDesc in resourceDesc['resources'].iteritems(): if futureDesc and 'resources' in futureDesc: future = futureDesc['resources'].get(methodName, {}) else: future = {} createResourceMethod(Resource, methodName, methodDesc, future) # Add <m>_next() methods to Resource if futureDesc and 'methods' in futureDesc: for methodName, methodDesc in futureDesc['methods'].iteritems(): if 'next' in methodDesc and methodName in resourceDesc['methods']: createNextMethod(Resource, methodName + '_next', resourceDesc['methods'][methodName], methodDesc['next']) return Resource()
Python
#!/usr/bin/python2.4 # # Copyright 2010 Google Inc. All Rights Reserved. """Model objects for requests and responses. Each API may support one or more serializations, such as JSON, Atom, etc. The model classes are responsible for converting between the wire format and the Python object representation. """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' import gflags import logging import urllib from anyjson import simplejson from errors import HttpError FLAGS = gflags.FLAGS gflags.DEFINE_boolean('dump_request_response', False, 'Dump all http server requests and responses. ' 'Must use apiclient.model.LoggingJsonModel as ' 'the model.' ) def _abstract(): raise NotImplementedError('You need to override this function') class Model(object): """Model base class. All Model classes should implement this interface. The Model serializes and de-serializes between a wire format such as JSON and a Python object representation. """ def request(self, headers, path_params, query_params, body_value): """Updates outgoing requests with a deserialized body. Args: headers: dict, request headers path_params: dict, parameters that appear in the request path query_params: dict, parameters that appear in the query body_value: object, the request body as a Python object, which must be serializable. Returns: A tuple of (headers, path_params, query, body) headers: dict, request headers path_params: dict, parameters that appear in the request path query: string, query part of the request URI body: string, the body serialized in the desired wire format. """ _abstract() def response(self, resp, content): """Convert the response wire format into a Python object. Args: resp: httplib2.Response, the HTTP response headers and status content: string, the body of the HTTP response Returns: The body de-serialized as a Python object. Raises: apiclient.errors.HttpError if a non 2xx response is received. """ _abstract() class JsonModel(Model): """Model class for JSON. Serializes and de-serializes between JSON and the Python object representation of HTTP request and response bodies. """ def __init__(self, data_wrapper=False): """Construct a JsonModel Args: data_wrapper: boolean, wrap requests and responses in a data wrapper """ self._data_wrapper = data_wrapper def request(self, headers, path_params, query_params, body_value): """Updates outgoing requests with JSON bodies. Args: headers: dict, request headers path_params: dict, parameters that appear in the request path query_params: dict, parameters that appear in the query body_value: object, the request body as a Python object, which must be serializable by simplejson. Returns: A tuple of (headers, path_params, query, body) headers: dict, request headers path_params: dict, parameters that appear in the request path query: string, query part of the request URI body: string, the body serialized as JSON """ query = self._build_query(query_params) headers['accept'] = 'application/json' headers['accept-encoding'] = 'gzip, deflate' if 'user-agent' in headers: headers['user-agent'] += ' ' else: headers['user-agent'] = '' headers['user-agent'] += 'google-api-python-client/1.0' if (isinstance(body_value, dict) and 'data' not in body_value and self._data_wrapper): body_value = {'data': body_value} if body_value is not None: headers['content-type'] = 'application/json' body_value = simplejson.dumps(body_value) return (headers, path_params, query, body_value) def _build_query(self, params): """Builds a query string. Args: params: dict, the query parameters Returns: The query parameters properly encoded into an HTTP URI query string. """ params.update({'alt': 'json'}) astuples = [] for key, value in params.iteritems(): if type(value) == type([]): for x in value: x = x.encode('utf-8') astuples.append((key, x)) else: if getattr(value, 'encode', False) and callable(value.encode): value = value.encode('utf-8') astuples.append((key, value)) return '?' + urllib.urlencode(astuples) def response(self, resp, content): """Convert the response wire format into a Python object. Args: resp: httplib2.Response, the HTTP response headers and status content: string, the body of the HTTP response Returns: The body de-serialized as a Python object. Raises: apiclient.errors.HttpError if a non 2xx response is received. """ # Error handling is TBD, for example, do we retry # for some operation/error combinations? if resp.status < 300: if resp.status == 204: # A 204: No Content response should be treated differently # to all the other success states return simplejson.loads('{}') body = simplejson.loads(content) if isinstance(body, dict) and 'data' in body: body = body['data'] return body else: logging.debug('Content from bad request was: %s' % content) raise HttpError(resp, content) class LoggingJsonModel(JsonModel): """A printable JsonModel class that supports logging response info.""" def response(self, resp, content): """An overloaded response method that will output debug info if requested. Args: resp: An httplib2.Response object. content: A string representing the response body. Returns: The body de-serialized as a Python object. """ if FLAGS.dump_request_response: logging.info('--response-start--') for h, v in resp.iteritems(): logging.info('%s: %s', h, v) if content: logging.info(content) logging.info('--response-end--') return super(LoggingJsonModel, self).response( resp, content) def request(self, headers, path_params, query_params, body_value): """An overloaded request method that will output debug info if requested. Args: headers: dict, request headers path_params: dict, parameters that appear in the request path query_params: dict, parameters that appear in the query body_value: object, the request body as a Python object, which must be serializable by simplejson. Returns: A tuple of (headers, path_params, query, body) headers: dict, request headers path_params: dict, parameters that appear in the request path query: string, query part of the request URI body: string, the body serialized as JSON """ (headers, path_params, query, body) = super( LoggingJsonModel, self).request( headers, path_params, query_params, body_value) if FLAGS.dump_request_response: logging.info('--request-start--') logging.info('-headers-start-') for h, v in headers.iteritems(): logging.info('%s: %s', h, v) logging.info('-headers-end-') logging.info('-path-parameters-start-') for h, v in path_params.iteritems(): logging.info('%s: %s', h, v) logging.info('-path-parameters-end-') logging.info('body: %s', body) logging.info('query: %s', query) logging.info('--request-end--') return (headers, path_params, query, body)
Python
#!/usr/bin/python2.4 # # Copyright 2010 Google Inc. All Rights Reserved. """Errors for the library. All exceptions defined by the library should be defined in this file. """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' from anyjson import simplejson class Error(Exception): """Base error for this module.""" pass class HttpError(Error): """HTTP data was invalid or unexpected.""" def __init__(self, resp, content, uri=None): self.resp = resp self.content = content self.uri = uri def _get_reason(self): """Calculate the reason for the error from the response content. """ if self.resp.get('content-type', '').startswith('application/json'): try: data = simplejson.loads(self.content) reason = data['error']['message'] except (ValueError, KeyError): reason = self.content else: reason = self.resp.reason return reason def __repr__(self): if self.uri: return '<HttpError %s when requesting %s returned "%s">' % ( self.resp.status, self.uri, self._get_reason()) else: return '<HttpError %s "%s">' % (self.resp.status, self._get_reason()) __str__ = __repr__ class InvalidJsonError(Error): """The JSON returned could not be parsed.""" pass class UnknownLinkType(Error): """Link type unknown or unexpected.""" pass
Python
# Copyright 2010 Google Inc. All Rights Reserved. """Utilities for OAuth. Utilities for making it easier to work with OAuth 1.0 credentials. """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' import pickle import threading from apiclient.oauth import Storage as BaseStorage class Storage(BaseStorage): """Store and retrieve a single credential to and from a file.""" def __init__(self, filename): self._filename = filename self._lock = threading.Lock() def get(self): """Retrieve Credential from file. Returns: apiclient.oauth.Credentials """ self._lock.acquire() try: f = open(self._filename, 'r') credentials = pickle.loads(f.read()) f.close() credentials.set_store(self.put) except: credentials = None self._lock.release() return credentials def put(self, credentials): """Write a pickled Credentials to file. Args: credentials: Credentials, the credentials to store. """ self._lock.acquire() f = open(self._filename, 'w') f.write(pickle.dumps(credentials)) f.close() self._lock.release()
Python
import apiclient import base64 import pickle from django.db import models class OAuthCredentialsField(models.Field): __metaclass__ = models.SubfieldBase def db_type(self): return 'VARCHAR' def to_python(self, value): if value is None: return None if isinstance(value, apiclient.oauth.Credentials): return value return pickle.loads(base64.b64decode(value)) def get_db_prep_value(self, value): return base64.b64encode(pickle.dumps(value)) class FlowThreeLeggedField(models.Field): __metaclass__ = models.SubfieldBase def db_type(self): return 'VARCHAR' def to_python(self, value): print "In to_python", value if value is None: return None if isinstance(value, apiclient.oauth.FlowThreeLegged): return value return pickle.loads(base64.b64decode(value)) def get_db_prep_value(self, value): return base64.b64encode(pickle.dumps(value))
Python
# Copyright (C) 2010 Google Inc. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. """Utilities for Google App Engine Utilities for making it easier to use the Google API Client for Python on Google App Engine. """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' import pickle from google.appengine.ext import db from apiclient.oauth import OAuthCredentials from apiclient.oauth import FlowThreeLegged class FlowThreeLeggedProperty(db.Property): """Utility property that allows easy storage and retreival of an apiclient.oauth.FlowThreeLegged""" # Tell what the user type is. data_type = FlowThreeLegged # For writing to datastore. def get_value_for_datastore(self, model_instance): flow = super(FlowThreeLeggedProperty, self).get_value_for_datastore(model_instance) return db.Blob(pickle.dumps(flow)) # For reading from datastore. def make_value_from_datastore(self, value): if value is None: return None return pickle.loads(value) def validate(self, value): if value is not None and not isinstance(value, FlowThreeLegged): raise BadValueError('Property %s must be convertible ' 'to a FlowThreeLegged instance (%s)' % (self.name, value)) return super(FlowThreeLeggedProperty, self).validate(value) def empty(self, value): return not value class OAuthCredentialsProperty(db.Property): """Utility property that allows easy storage and retrieval of apiclient.oath.OAuthCredentials """ # Tell what the user type is. data_type = OAuthCredentials # For writing to datastore. def get_value_for_datastore(self, model_instance): cred = super(OAuthCredentialsProperty, self).get_value_for_datastore(model_instance) return db.Blob(pickle.dumps(cred)) # For reading from datastore. def make_value_from_datastore(self, value): if value is None: return None return pickle.loads(value) def validate(self, value): if value is not None and not isinstance(value, OAuthCredentials): raise BadValueError('Property %s must be convertible ' 'to an OAuthCredentials instance (%s)' % (self.name, value)) return super(OAuthCredentialsProperty, self).validate(value) def empty(self, value): return not value class StorageByKeyName(object): """Store and retrieve a single credential to and from the App Engine datastore. This Storage helper presumes the Credentials have been stored as a CredenialsProperty on a datastore model class, and that entities are stored by key_name. """ def __init__(self, model, key_name, property_name): """Constructor for Storage. Args: model: db.Model, model class key_name: string, key name for the entity that has the credentials property_name: string, name of the property that is a CredentialsProperty """ self.model = model self.key_name = key_name self.property_name = property_name def get(self): """Retrieve Credential from datastore. Returns: Credentials """ entity = self.model.get_or_insert(self.key_name) credential = getattr(entity, self.property_name) if credential and hasattr(credential, 'set_store'): credential.set_store(self.put) return credential def put(self, credentials): """Write a Credentials to the datastore. Args: credentials: Credentials, the credentials to store. """ entity = self.model.get_or_insert(self.key_name) setattr(entity, self.property_name, credentials) entity.put()
Python
# Copyright (C) 2010 Google Inc. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. """Command-line tools for authenticating via OAuth 1.0 Do the OAuth 1.0 Three Legged Dance for a command line application. Stores the generated credentials in a common file that is used by other example apps in the same directory. """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' __all__ = ["run"] import BaseHTTPServer import logging import socket import sys from optparse import OptionParser from apiclient.oauth import RequestError try: from urlparse import parse_qsl except ImportError: from cgi import parse_qsl class ClientRedirectServer(BaseHTTPServer.HTTPServer): """A server to handle OAuth 1.0 redirects back to localhost. Waits for a single request and parses the query parameters into query_params and then stops serving. """ query_params = {} class ClientRedirectHandler(BaseHTTPServer.BaseHTTPRequestHandler): """A handler for OAuth 2.0 redirects back to localhost. Waits for a single request and parses the query parameters into the servers query_params and then stops serving. """ def do_GET(s): """Handle a GET request Parses the query parameters and prints a message if the flow has completed. Note that we can't detect if an error occurred. """ s.send_response(200) s.send_header("Content-type", "text/html") s.end_headers() query = s.path.split('?', 1)[-1] query = dict(parse_qsl(query)) s.server.query_params = query s.wfile.write("<html><head><title>Authentication Status</title></head>") s.wfile.write("<body><p>The authentication flow has completed.</p>") s.wfile.write("</body></html>") def log_message(self, format, *args): """Do not log messages to stdout while running as command line program.""" pass def run(flow, storage): """Core code for a command-line application. Args: flow: Flow, an OAuth 1.0 Flow to step through. storage: Storage, a Storage to store the credential in. Returns: Credentials, the obtained credential. Exceptions: RequestError: if step2 of the flow fails. Args: """ parser = OptionParser() parser.add_option("-p", "--no_local_web_server", dest="localhost", action="store_false", default=True, help="Do not run a web server on localhost to handle redirect URIs") parser.add_option("-w", "--local_web_server", dest="localhost", action="store_true", default=True, help="Run a web server on localhost to handle redirect URIs") (options, args) = parser.parse_args() host_name = 'localhost' port_numbers = [8080, 8090] if options.localhost: server_class = BaseHTTPServer.HTTPServer try: port_number = port_numbers[0] httpd = server_class((host_name, port_number), ClientRedirectHandler) except socket.error: port_number = port_numbers[1] try: httpd = server_class((host_name, port_number), ClientRedirectHandler) except socket.error: options.localhost = False if options.localhost: oauth_callback = 'http://%s:%s/' % (host_name, port_number) else: oauth_callback = 'oob' authorize_url = flow.step1_get_authorize_url(oauth_callback) print 'Go to the following link in your browser:' print authorize_url print if options.localhost: httpd.handle_request() if 'error' in httpd.query_params: sys.exit('Authentication request was rejected.') if 'oauth_verifier' in httpd.query_params: code = httpd.query_params['oauth_verifier'] else: accepted = 'n' while accepted.lower() == 'n': accepted = raw_input('Have you authorized me? (y/n) ') code = raw_input('What is the verification code? ').strip() try: credentials = flow.step2_exchange(code) except RequestError: sys.exit('The authentication has failed.') storage.put(credentials) credentials.set_store(storage.put) print "You have successfully authenticated." return credentials
Python
#!/usr/bin/python2.4 # # Copyright 2010 Google Inc. All Rights Reserved. """Errors for the library. All exceptions defined by the library should be defined in this file. """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' from anyjson import simplejson class Error(Exception): """Base error for this module.""" pass class HttpError(Error): """HTTP data was invalid or unexpected.""" def __init__(self, resp, content, uri=None): self.resp = resp self.content = content self.uri = uri def _get_reason(self): """Calculate the reason for the error from the response content. """ if self.resp.get('content-type', '').startswith('application/json'): try: data = simplejson.loads(self.content) reason = data['error']['message'] except (ValueError, KeyError): reason = self.content else: reason = self.resp.reason return reason def __repr__(self): if self.uri: return '<HttpError %s when requesting %s returned "%s">' % ( self.resp.status, self.uri, self._get_reason()) else: return '<HttpError %s "%s">' % (self.resp.status, self._get_reason()) __str__ = __repr__ class InvalidJsonError(Error): """The JSON returned could not be parsed.""" pass class UnknownLinkType(Error): """Link type unknown or unexpected.""" pass
Python
# Copyright (C) 2010 Google Inc. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. """Utility module to import a JSON module Hides all the messy details of exactly where we get a simplejson module from. """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' try: # pragma: no cover import simplejson except ImportError: # pragma: no cover try: # Try to import from django, should work on App Engine from django.utils import simplejson except ImportError: # Should work for Python2.6 and higher. import json as simplejson
Python
# Early, and incomplete implementation of -04. # import re import urllib RESERVED = ":/?#[]@!$&'()*+,;=" OPERATOR = "+./;?|!@" EXPLODE = "*+" MODIFIER = ":^" TEMPLATE = re.compile(r"{(?P<operator>[\+\./;\?|!@])?(?P<varlist>[^}]+)}", re.UNICODE) VAR = re.compile(r"^(?P<varname>[^=\+\*:\^]+)((?P<explode>[\+\*])|(?P<partial>[:\^]-?[0-9]+))?(=(?P<default>.*))?$", re.UNICODE) def _tostring(varname, value, explode, operator, safe=""): if type(value) == type([]): if explode == "+": return ",".join([varname + "." + urllib.quote(x, safe) for x in value]) else: return ",".join([urllib.quote(x, safe) for x in value]) if type(value) == type({}): keys = value.keys() keys.sort() if explode == "+": return ",".join([varname + "." + urllib.quote(key, safe) + "," + urllib.quote(value[key], safe) for key in keys]) else: return ",".join([urllib.quote(key, safe) + "," + urllib.quote(value[key], safe) for key in keys]) else: return urllib.quote(value, safe) def _tostring_path(varname, value, explode, operator, safe=""): joiner = operator if type(value) == type([]): if explode == "+": return joiner.join([varname + "." + urllib.quote(x, safe) for x in value]) elif explode == "*": return joiner.join([urllib.quote(x, safe) for x in value]) else: return ",".join([urllib.quote(x, safe) for x in value]) elif type(value) == type({}): keys = value.keys() keys.sort() if explode == "+": return joiner.join([varname + "." + urllib.quote(key, safe) + joiner + urllib.quote(value[key], safe) for key in keys]) elif explode == "*": return joiner.join([urllib.quote(key, safe) + joiner + urllib.quote(value[key], safe) for key in keys]) else: return ",".join([urllib.quote(key, safe) + "," + urllib.quote(value[key], safe) for key in keys]) else: if value: return urllib.quote(value, safe) else: return "" def _tostring_query(varname, value, explode, operator, safe=""): joiner = operator varprefix = "" if operator == "?": joiner = "&" varprefix = varname + "=" if type(value) == type([]): if 0 == len(value): return "" if explode == "+": return joiner.join([varname + "=" + urllib.quote(x, safe) for x in value]) elif explode == "*": return joiner.join([urllib.quote(x, safe) for x in value]) else: return varprefix + ",".join([urllib.quote(x, safe) for x in value]) elif type(value) == type({}): if 0 == len(value): return "" keys = value.keys() keys.sort() if explode == "+": return joiner.join([varname + "." + urllib.quote(key, safe) + "=" + urllib.quote(value[key], safe) for key in keys]) elif explode == "*": return joiner.join([urllib.quote(key, safe) + "=" + urllib.quote(value[key], safe) for key in keys]) else: return varprefix + ",".join([urllib.quote(key, safe) + "," + urllib.quote(value[key], safe) for key in keys]) else: if value: return varname + "=" + urllib.quote(value, safe) else: return varname TOSTRING = { "" : _tostring, "+": _tostring, ";": _tostring_query, "?": _tostring_query, "/": _tostring_path, ".": _tostring_path, } def expand(template, vars): def _sub(match): groupdict = match.groupdict() operator = groupdict.get('operator') if operator is None: operator = '' varlist = groupdict.get('varlist') safe = "@" if operator == '+': safe = RESERVED varspecs = varlist.split(",") varnames = [] defaults = {} for varspec in varspecs: m = VAR.search(varspec) groupdict = m.groupdict() varname = groupdict.get('varname') explode = groupdict.get('explode') partial = groupdict.get('partial') default = groupdict.get('default') if default: defaults[varname] = default varnames.append((varname, explode, partial)) retval = [] joiner = operator prefix = operator if operator == "+": prefix = "" joiner = "," if operator == "?": joiner = "&" if operator == "": joiner = "," for varname, explode, partial in varnames: if varname in vars: value = vars[varname] #if not value and (type(value) == type({}) or type(value) == type([])) and varname in defaults: if not value and value != "" and varname in defaults: value = defaults[varname] elif varname in defaults: value = defaults[varname] else: continue retval.append(TOSTRING[operator](varname, value, explode, operator, safe=safe)) if "".join(retval): return prefix + joiner.join(retval) else: return "" return TEMPLATE.sub(_sub, template)
Python
#!/usr/bin/env python """Execute all sample applications. Runs over all the sample applications, determines their type (App Engine, Django, or a command-line application), and then runs them checking for a good return status in the case of command-line applications and a 200 OK response in the case of the App Engine and Django samples. """ import gflags import httplib2 import logging import os import signal import subprocess import sys import time FLAGS = gflags.FLAGS gflags.DEFINE_list('samples_to_skip', ['latitude'], 'A comma separated list of project directory names to be skipped.') gflags.DEFINE_enum('logging_level', 'INFO', ['DEBUG', 'INFO', 'WARNING', 'ERROR', 'CRITICAL'], 'Set the level of logging detail.') gflags.DEFINE_string('app_engine_dir', '../google_appengine/', 'Directory where Google App Engine is installed.') gflags.DEFINE_string('sample_root', 'samples/oauth2', 'The root directory for all the samples.') def main(argv): try: argv = FLAGS(argv) except gflags.FlagsError, e: print '%s\\nUsage: %s ARGS\\n%s' % (e, argv[0], FLAGS) sys.exit(1) logging.getLogger().setLevel(getattr(logging, FLAGS.logging_level)) for dirname in os.listdir(FLAGS.sample_root): if dirname in FLAGS.samples_to_skip: logging.debug('Skipping ' + fulldirname + ' (blacklist)') continue fulldirname = os.path.join(FLAGS.sample_root, dirname) filelist = os.listdir(fulldirname) if 'settings.py' in filelist and 'manage.py' in filelist: logging.info(fulldirname + ' [Django]') proc = subprocess.Popen( [os.path.join(fulldirname, 'manage.py'), 'runserver']) # Now just wait, because Django actually spawns a sub-process that does # the I/O and does something funky with stdout so we can't read it and # figure out when it is started. time.sleep(3) h = httplib2.Http() resp, content = h.request('http://localhost:8000/') assert(200 == resp.status) time.sleep(1) logging.debug('Django ppid: %d', proc.pid) # Find and kill the sub-process manage.py forked. findpids = subprocess.Popen(['ps', '--ppid', str(proc.pid), 'o', 'pid',], stdout=subprocess.PIPE) for p in findpids.stdout.readlines(): if 'PID' not in p: os.kill(int(p), signal.SIGINT) os.kill(proc.pid, signal.SIGINT) proc.wait() elif 'app.yaml' in filelist: logging.info(fulldirname + ' [App Engine]') proc = subprocess.Popen( [os.path.join(FLAGS.app_engine_dir, 'dev_appserver.py'), fulldirname], stdout=subprocess.PIPE, stderr=subprocess.STDOUT) line = proc.stdout.readline() logging.debug('READ: ' + line) while '] Running application' not in line: line = proc.stdout.readline() logging.debug('READ: ' + line) h = httplib2.Http() resp, content = h.request('http://localhost:8080/') assert(200 == resp.status) time.sleep(1) os.kill(proc.pid, signal.SIGINT) proc.wait() else: logging.info(fulldirname + ' [Command-line]') for filename in os.listdir(fulldirname): if filename.endswith('.py'): logging.info('Running: ' + filename) proc = subprocess.Popen(['python', os.path.join(fulldirname, filename)]) returncode = proc.wait() assert(returncode == 0) if __name__ == '__main__': main(sys.argv)
Python
#!/usr/bin/env python # Copyright (c) 2010, Google Inc. # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. """Module to enforce different constraints on flags. A validator represents an invariant, enforced over a one or more flags. See 'FLAGS VALIDATORS' in flags.py's docstring for a usage manual. """ __author__ = 'olexiy@google.com (Olexiy Oryeshko)' class Error(Exception): """Thrown If validator constraint is not satisfied.""" class Validator(object): """Base class for flags validators. Users should NOT overload these classes, and use flags.Register... methods instead. """ # Used to assign each validator an unique insertion_index validators_count = 0 def __init__(self, checker, message): """Constructor to create all validators. Args: checker: function to verify the constraint. Input of this method varies, see SimpleValidator and DictionaryValidator for a detailed description. message: string, error message to be shown to the user """ self.checker = checker self.message = message Validator.validators_count += 1 # Used to assert validators in the order they were registered (CL/18694236) self.insertion_index = Validator.validators_count def Verify(self, flag_values): """Verify that constraint is satisfied. flags library calls this method to verify Validator's constraint. Args: flag_values: flags.FlagValues, containing all flags Raises: Error: if constraint is not satisfied. """ param = self._GetInputToCheckerFunction(flag_values) if not self.checker(param): raise Error(self.message) def GetFlagsNames(self): """Return the names of the flags checked by this validator. Returns: [string], names of the flags """ raise NotImplementedError('This method should be overloaded') def PrintFlagsWithValues(self, flag_values): raise NotImplementedError('This method should be overloaded') def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues, containing all flags. Returns: Return type depends on the specific validator. """ raise NotImplementedError('This method should be overloaded') class SimpleValidator(Validator): """Validator behind RegisterValidator() method. Validates that a single flag passes its checker function. The checker function takes the flag value and returns True (if value looks fine) or, if flag value is not valid, either returns False or raises an Exception.""" def __init__(self, flag_name, checker, message): """Constructor. Args: flag_name: string, name of the flag. checker: function to verify the validator. input - value of the corresponding flag (string, boolean, etc). output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise Error. message: string, error message to be shown to the user if validator's condition is not satisfied """ super(SimpleValidator, self).__init__(checker, message) self.flag_name = flag_name def GetFlagsNames(self): return [self.flag_name] def PrintFlagsWithValues(self, flag_values): return 'flag --%s=%s' % (self.flag_name, flag_values[self.flag_name].value) def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues Returns: value of the corresponding flag. """ return flag_values[self.flag_name].value class DictionaryValidator(Validator): """Validator behind RegisterDictionaryValidator method. Validates that flag values pass their common checker function. The checker function takes flag values and returns True (if values look fine) or, if values are not valid, either returns False or raises an Exception. """ def __init__(self, flag_names, checker, message): """Constructor. Args: flag_names: [string], containing names of the flags used by checker. checker: function to verify the validator. input - dictionary, with keys() being flag_names, and value for each key being the value of the corresponding flag (string, boolean, etc). output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise Error. message: string, error message to be shown to the user if validator's condition is not satisfied """ super(DictionaryValidator, self).__init__(checker, message) self.flag_names = flag_names def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues Returns: dictionary, with keys() being self.lag_names, and value for each key being the value of the corresponding flag (string, boolean, etc). """ return dict([key, flag_values[key].value] for key in self.flag_names) def PrintFlagsWithValues(self, flag_values): prefix = 'flags ' flags_with_values = [] for key in self.flag_names: flags_with_values.append('%s=%s' % (key, flag_values[key].value)) return prefix + ', '.join(flags_with_values) def GetFlagsNames(self): return self.flag_names
Python
"""SocksiPy - Python SOCKS module. Version 1.00 Copyright 2006 Dan-Haim. All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. 3. Neither the name of Dan Haim nor the names of his contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY DAN HAIM "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL DAN HAIM OR HIS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. This module provides a standard socket-like interface for Python for tunneling connections through SOCKS proxies. """ """ Minor modifications made by Christopher Gilbert (http://motomastyle.com/) for use in PyLoris (http://pyloris.sourceforge.net/) Minor modifications made by Mario Vilas (http://breakingcode.wordpress.com/) mainly to merge bug fixes found in Sourceforge """ import socket if getattr(socket, 'socket', None) is None: raise ImportError('socket.socket missing, proxy support unusable') import struct import sys PROXY_TYPE_SOCKS4 = 1 PROXY_TYPE_SOCKS5 = 2 PROXY_TYPE_HTTP = 3 _defaultproxy = None # Small hack for Python 2.x if sys.version_info[0] <= 2: def bytes(obj, enc=None): return obj class ProxyError(Exception): def __init__(self, value): self.value = value def __str__(self): return repr(self.value) class GeneralProxyError(ProxyError): def __init__(self, value): self.value = value def __str__(self): return repr(self.value) class Socks5AuthError(ProxyError): def __init__(self, value): self.value = value def __str__(self): return repr(self.value) class Socks5Error(ProxyError): def __init__(self, value): self.value = value def __str__(self): return repr(self.value) class Socks4Error(ProxyError): def __init__(self, value): self.value = value def __str__(self): return repr(self.value) class HTTPError(ProxyError): def __init__(self, value): self.value = value def __str__(self): return repr(self.value) _generalerrors = ("success", "invalid data", "not connected", "not available", "bad proxy type", "bad input") _socks5errors = ("succeeded", "general SOCKS server failure", "connection not allowed by ruleset", "Network unreachable", "Host unreachable", "Connection refused", "TTL expired", "Command not supported", "Address type not supported", "Unknown error") _socks5autherrors = ("succeeded", "authentication is required", "all offered authentication methods were rejected", "unknown username or invalid password", "unknown error") _socks4errors = ("request granted", "request rejected or failed", ("request rejected because SOCKS server cannot connect to " "identd on the client"), ("request rejected because the client program and identd" " report different user-ids"), "unknown error") def setdefaultproxy(proxytype=None, addr=None, port=None, rdns=True, username=None, password=None): """setdefaultproxy(proxytype, addr[, port[, rdns[, username[, password]]]]) Sets a default proxy which all further socksocket objects will use, unless explicitly changed. """ global _defaultproxy _defaultproxy = (proxytype, addr, port, rdns, username, password) class socksocket(socket.socket): """socksocket([family[, type[, proto]]]) -> socket object Open a SOCKS enabled socket. The parameters are the same as those of the standard socket init. In order for SOCKS to work, you must specify family=AF_INET, type=SOCK_STREAM and proto=0. """ def __init__(self, family=socket.AF_INET, type=socket.SOCK_STREAM, proto=0, _sock=None): socket.socket.__init__(self, family, type, proto, _sock) if _defaultproxy != None: self.__proxy = _defaultproxy else: self.__proxy = (None, None, None, None, None, None) self.__proxysockname = None self.__proxypeername = None def __decode(self, bytes): if getattr(bytes, 'decode', False): try: bytes = bytes.decode() except Exception: pass return bytes def __encode(self, bytes): if getattr(bytes, 'encode', False): try: bytes = bytes.encode() except Exception: pass return bytes def __recvall(self, count): """__recvall(count) -> data Receive EXACTLY the number of bytes requested from the socket. Blocks until the required number of bytes have been received. """ data = bytes("") while len(data) < count: d = self.recv(count - len(data)) if not d: raise GeneralProxyError( (0, "connection closed unexpectedly")) data = data + self.__decode(d) return data def sendall(self, bytes): socket.socket.sendall(self, self.__encode(bytes)) def setproxy(self, proxytype=None, addr=None, port=None, rdns=True, username=None, password=None): """setproxy(proxytype, addr[, port[, rdns[, username[, password]]]]) Sets the proxy to be used. proxytype - The type of the proxy to be used. Three types are supported: PROXY_TYPE_SOCKS4 (including socks4a), PROXY_TYPE_SOCKS5 and PROXY_TYPE_HTTP addr - The address of the server (IP or DNS). port - The port of the server. Defaults to 1080 for SOCKS servers and 8080 for HTTP proxy servers. rdns - Should DNS queries be preformed on the remote side (rather than the local side). The default is True. Note: This has no effect with SOCKS4 servers. username - Username to authenticate with to the server. The default is no authentication. password - Password to authenticate with to the server. Only relevant when username is also provided. """ self.__proxy = (proxytype, addr, port, rdns, username, password) def __negotiatesocks5(self, destaddr, destport): """__negotiatesocks5(self,destaddr,destport) Negotiates a connection through a SOCKS5 server. """ # First we'll send the authentication packages we support. if (self.__proxy[4] != None) and (self.__proxy[5] != None): # The username/password details were supplied to the # setproxy method so we support the USERNAME/PASSWORD # authentication (in addition to the standard none). self.sendall("\x05\x02\x00\x02") else: # No username/password were entered, therefore we # only support connections with no authentication. self.sendall("\x05\x01\x00") # We'll receive the server's response to determine which # method was selected chosenauth = self.__recvall(2) if chosenauth[0] != "\x05": self.close() raise GeneralProxyError((1, _generalerrors[1])) # Check the chosen authentication method if chosenauth[1] == "\x00": # No authentication is required pass elif chosenauth[1] == "\x02": # Okay, we need to perform a basic username/password # authentication. self.sendall("\x01" + chr(len(self.__proxy[4])) + self.__proxy[4] + chr(len(self.__proxy[5])) + self.__proxy[5]) authstat = self.__recvall(2) if authstat[0] != "\x01": # Bad response self.close() raise GeneralProxyError((1, _generalerrors[1])) if authstat[1] != "\x00": # Authentication failed self.close() raise Socks5AuthError((3, _socks5autherrors[3])) # Authentication succeeded else: # Reaching here is always bad self.close() if chosenauth[1] == "\xFF": raise Socks5AuthError((2, _socks5autherrors[2])) else: raise GeneralProxyError((1, _generalerrors[1])) # Now we can request the actual connection req = "\x05\x01\x00" # If the given destination address is an IP address, we'll # use the IPv4 address request even if remote resolving was specified. try: ipaddr = socket.inet_aton(destaddr) req = req + "\x01" + ipaddr except socket.error: # Well it's not an IP number, so it's probably a DNS name. if self.__proxy[3] == True: # Resolve remotely ipaddr = None req = req + "\x03" + chr(len(destaddr)) + destaddr else: # Resolve locally ipaddr = socket.inet_aton(socket.gethostbyname(destaddr)) req = req + "\x01" + ipaddr req = req + self.__decode(struct.pack(">H", destport)) self.sendall(req) # Get the response resp = self.__recvall(4) if resp[0] != "\x05": self.close() raise GeneralProxyError((1, _generalerrors[1])) elif resp[1] != "\x00": # Connection failed self.close() if ord(resp[1]) <= 8: raise Socks5Error((ord(resp[1]), _socks5errors[ord(resp[1])])) else: raise Socks5Error((9, _socks5errors[9])) # Get the bound address/port elif resp[3] == "\x01": boundaddr = self.__recvall(4) elif resp[3] == "\x03": resp = resp + self.recv(1) boundaddr = self.__recvall(ord(resp[4])) else: self.close() raise GeneralProxyError((1, _generalerrors[1])) boundport = struct.unpack(">H", bytes(self.__recvall(2), 'utf8'))[0] self.__proxysockname = boundaddr, boundport if ipaddr != None: self.__proxypeername = (socket.inet_ntoa(ipaddr), destport) else: self.__proxypeername = (destaddr, destport) def getproxysockname(self): """getsockname() -> address info Returns the bound IP address and port number at the proxy. """ return self.__proxysockname def getproxypeername(self): """getproxypeername() -> address info Returns the IP and port number of the proxy. """ return socket.socket.getpeername(self) def getpeername(self): """getpeername() -> address info Returns the IP address and port number of the destination machine (note: getproxypeername returns the proxy) """ return self.__proxypeername def __negotiatesocks4(self, destaddr, destport): """__negotiatesocks4(self,destaddr,destport) Negotiates a connection through a SOCKS4 server. """ # Check if the destination address provided is an IP address rmtrslv = False try: ipaddr = socket.inet_aton(destaddr) except socket.error: # It's a DNS name. Check where it should be resolved. if self.__proxy[3] == True: ipaddr = "\x00\x00\x00\x01" rmtrslv = True else: ipaddr = socket.inet_aton(socket.gethostbyname(destaddr)) # Construct the request packet req = "\x04\x01" + self.__decode(struct.pack(">H", destport)) + ipaddr # The username parameter is considered userid for SOCKS4 if self.__proxy[4] != None: req = req + self.__proxy[4] req = req + "\x00" # DNS name if remote resolving is required # NOTE: This is actually an extension to the SOCKS4 protocol # called SOCKS4A and may not be supported in all cases. if rmtrslv==True: req = req + destaddr + "\x00" self.sendall(req) # Get the response from the server resp = self.__recvall(8) if resp[0] != "\x00": # Bad data self.close() raise GeneralProxyError((1, _generalerrors[1])) if resp[1] != "\x5A": # Server returned an error self.close() if ord(resp[1]) in (91,92,93): self.close() raise Socks4Error((ord(resp[1]), _socks4errors[ord(resp[1])-90])) else: raise Socks4Error((94,_socks4errors[4])) # Get the bound address/port self.__proxysockname = (socket.inet_ntoa(resp[4:]),struct.unpack(">H",bytes(resp[2:4],'utf8'))[0]) if rmtrslv != None: self.__proxypeername = (socket.inet_ntoa(ipaddr),destport) else: self.__proxypeername = (destaddr, destport) def __negotiatehttp(self, destaddr, destport): """__negotiatehttp(self,destaddr,destport) Negotiates a connection through an HTTP server. """ # If we need to resolve locally, we do this now if self.__proxy[3] == False: addr = socket.gethostbyname(destaddr) else: addr = destaddr self.sendall(("CONNECT %s:%s HTTP/1.1\r\n" "Host: %s\r\n\r\n") % (addr, destport, destaddr)) # We read the response until we get the string "\r\n\r\n" resp = self.recv(1) while resp.find("\r\n\r\n") == -1: resp = resp + self.recv(1) # We just need the first line to check if the connection # was successful statusline = resp.splitlines()[0].split(" ", 2) if statusline[0] not in ("HTTP/1.0", "HTTP/1.1"): self.close() raise GeneralProxyError((1, _generalerrors[1])) try: statuscode = int(statusline[1]) except ValueError: self.close() raise GeneralProxyError((1, _generalerrors[1])) if statuscode != 200: self.close() raise HTTPError((statuscode, statusline[2])) self.__proxysockname = ("0.0.0.0", 0) self.__proxypeername = (addr, destport) def connect(self, destpair): """connect(self,despair) Connects to the specified destination through a proxy. destpar - A tuple of the IP/DNS address and the port number. (identical to socket's connect). To select the proxy server use setproxy(). """ # Do a minimal input check first # TODO(durin42): seriously? type checking? do we care? if ((not isinstance(destpair, (list, tuple))) or len(destpair) < 2 or not isinstance(destpair[0], str) or not isinstance(destpair[1], int)): raise GeneralProxyError((5, _generalerrors[5])) if self.__proxy[0] == PROXY_TYPE_SOCKS5: if self.__proxy[2] != None: portnum = self.__proxy[2] else: portnum = 1080 socket.socket.connect(self,(self.__proxy[1], portnum)) self.__negotiatesocks5(destpair[0], destpair[1]) elif self.__proxy[0] == PROXY_TYPE_SOCKS4: if self.__proxy[2] != None: portnum = self.__proxy[2] else: portnum = 1080 socket.socket.connect(self, (self.__proxy[1], portnum)) self.__negotiatesocks4(destpair[0], destpair[1]) elif self.__proxy[0] == PROXY_TYPE_HTTP: if self.__proxy[2] != None: portnum = self.__proxy[2] else: portnum = 8080 socket.socket.connect(self, (self.__proxy[1], portnum)) self.__negotiatehttp(destpair[0], destpair[1]) elif self.__proxy[0] == None: socket.socket.connect(self, (destpair[0], destpair[1])) else: raise GeneralProxyError((4, _generalerrors[4]))
Python
""" iri2uri Converts an IRI to a URI. """ __author__ = "Joe Gregorio (joe@bitworking.org)" __copyright__ = "Copyright 2006, Joe Gregorio" __contributors__ = [] __version__ = "1.0.0" __license__ = "MIT" __history__ = """ """ import urlparse # Convert an IRI to a URI following the rules in RFC 3987 # # The characters we need to enocde and escape are defined in the spec: # # iprivate = %xE000-F8FF / %xF0000-FFFFD / %x100000-10FFFD # ucschar = %xA0-D7FF / %xF900-FDCF / %xFDF0-FFEF # / %x10000-1FFFD / %x20000-2FFFD / %x30000-3FFFD # / %x40000-4FFFD / %x50000-5FFFD / %x60000-6FFFD # / %x70000-7FFFD / %x80000-8FFFD / %x90000-9FFFD # / %xA0000-AFFFD / %xB0000-BFFFD / %xC0000-CFFFD # / %xD0000-DFFFD / %xE1000-EFFFD escape_range = [ (0xA0, 0xD7FF ), (0xE000, 0xF8FF ), (0xF900, 0xFDCF ), (0xFDF0, 0xFFEF), (0x10000, 0x1FFFD ), (0x20000, 0x2FFFD ), (0x30000, 0x3FFFD), (0x40000, 0x4FFFD ), (0x50000, 0x5FFFD ), (0x60000, 0x6FFFD), (0x70000, 0x7FFFD ), (0x80000, 0x8FFFD ), (0x90000, 0x9FFFD), (0xA0000, 0xAFFFD ), (0xB0000, 0xBFFFD ), (0xC0000, 0xCFFFD), (0xD0000, 0xDFFFD ), (0xE1000, 0xEFFFD), (0xF0000, 0xFFFFD ), (0x100000, 0x10FFFD) ] def encode(c): retval = c i = ord(c) for low, high in escape_range: if i < low: break if i >= low and i <= high: retval = "".join(["%%%2X" % ord(o) for o in c.encode('utf-8')]) break return retval def iri2uri(uri): """Convert an IRI to a URI. Note that IRIs must be passed in a unicode strings. That is, do not utf-8 encode the IRI before passing it into the function.""" if isinstance(uri ,unicode): (scheme, authority, path, query, fragment) = urlparse.urlsplit(uri) authority = authority.encode('idna') # For each character in 'ucschar' or 'iprivate' # 1. encode as utf-8 # 2. then %-encode each octet of that utf-8 uri = urlparse.urlunsplit((scheme, authority, path, query, fragment)) uri = "".join([encode(c) for c in uri]) return uri if __name__ == "__main__": import unittest class Test(unittest.TestCase): def test_uris(self): """Test that URIs are invariant under the transformation.""" invariant = [ u"ftp://ftp.is.co.za/rfc/rfc1808.txt", u"http://www.ietf.org/rfc/rfc2396.txt", u"ldap://[2001:db8::7]/c=GB?objectClass?one", u"mailto:John.Doe@example.com", u"news:comp.infosystems.www.servers.unix", u"tel:+1-816-555-1212", u"telnet://192.0.2.16:80/", u"urn:oasis:names:specification:docbook:dtd:xml:4.1.2" ] for uri in invariant: self.assertEqual(uri, iri2uri(uri)) def test_iri(self): """ Test that the right type of escaping is done for each part of the URI.""" self.assertEqual("http://xn--o3h.com/%E2%98%84", iri2uri(u"http://\N{COMET}.com/\N{COMET}")) self.assertEqual("http://bitworking.org/?fred=%E2%98%84", iri2uri(u"http://bitworking.org/?fred=\N{COMET}")) self.assertEqual("http://bitworking.org/#%E2%98%84", iri2uri(u"http://bitworking.org/#\N{COMET}")) self.assertEqual("#%E2%98%84", iri2uri(u"#\N{COMET}")) self.assertEqual("/fred?bar=%E2%98%9A#%E2%98%84", iri2uri(u"/fred?bar=\N{BLACK LEFT POINTING INDEX}#\N{COMET}")) self.assertEqual("/fred?bar=%E2%98%9A#%E2%98%84", iri2uri(iri2uri(u"/fred?bar=\N{BLACK LEFT POINTING INDEX}#\N{COMET}"))) self.assertNotEqual("/fred?bar=%E2%98%9A#%E2%98%84", iri2uri(u"/fred?bar=\N{BLACK LEFT POINTING INDEX}#\N{COMET}".encode('utf-8'))) unittest.main()
Python
from __future__ import generators """ httplib2 A caching http interface that supports ETags and gzip to conserve bandwidth. Requires Python 2.3 or later Changelog: 2007-08-18, Rick: Modified so it's able to use a socks proxy if needed. """ __author__ = "Joe Gregorio (joe@bitworking.org)" __copyright__ = "Copyright 2006, Joe Gregorio" __contributors__ = ["Thomas Broyer (t.broyer@ltgt.net)", "James Antill", "Xavier Verges Farrero", "Jonathan Feinberg", "Blair Zajac", "Sam Ruby", "Louis Nyffenegger"] __license__ = "MIT" __version__ = "$Rev$" import re import sys import email import email.Utils import email.Message import email.FeedParser import StringIO import gzip import zlib import httplib import urlparse import base64 import os import copy import calendar import time import random import errno # remove depracated warning in python2.6 try: from hashlib import sha1 as _sha, md5 as _md5 except ImportError: import sha import md5 _sha = sha.new _md5 = md5.new import hmac from gettext import gettext as _ import socket try: from httplib2 import socks except ImportError: socks = None # Build the appropriate socket wrapper for ssl try: import ssl # python 2.6 _ssl_wrap_socket = ssl.wrap_socket except ImportError: def _ssl_wrap_socket(sock, key_file, cert_file): ssl_sock = socket.ssl(sock, key_file, cert_file) return httplib.FakeSocket(sock, ssl_sock) if sys.version_info >= (2,3): from iri2uri import iri2uri else: def iri2uri(uri): return uri def has_timeout(timeout): # python 2.6 if hasattr(socket, '_GLOBAL_DEFAULT_TIMEOUT'): return (timeout is not None and timeout is not socket._GLOBAL_DEFAULT_TIMEOUT) return (timeout is not None) __all__ = ['Http', 'Response', 'ProxyInfo', 'HttpLib2Error', 'RedirectMissingLocation', 'RedirectLimit', 'FailedToDecompressContent', 'UnimplementedDigestAuthOptionError', 'UnimplementedHmacDigestAuthOptionError', 'debuglevel', 'ProxiesUnavailableError'] # The httplib debug level, set to a non-zero value to get debug output debuglevel = 0 # Python 2.3 support if sys.version_info < (2,4): def sorted(seq): seq.sort() return seq # Python 2.3 support def HTTPResponse__getheaders(self): """Return list of (header, value) tuples.""" if self.msg is None: raise httplib.ResponseNotReady() return self.msg.items() if not hasattr(httplib.HTTPResponse, 'getheaders'): httplib.HTTPResponse.getheaders = HTTPResponse__getheaders # All exceptions raised here derive from HttpLib2Error class HttpLib2Error(Exception): pass # Some exceptions can be caught and optionally # be turned back into responses. class HttpLib2ErrorWithResponse(HttpLib2Error): def __init__(self, desc, response, content): self.response = response self.content = content HttpLib2Error.__init__(self, desc) class RedirectMissingLocation(HttpLib2ErrorWithResponse): pass class RedirectLimit(HttpLib2ErrorWithResponse): pass class FailedToDecompressContent(HttpLib2ErrorWithResponse): pass class UnimplementedDigestAuthOptionError(HttpLib2ErrorWithResponse): pass class UnimplementedHmacDigestAuthOptionError(HttpLib2ErrorWithResponse): pass class RelativeURIError(HttpLib2Error): pass class ServerNotFoundError(HttpLib2Error): pass class ProxiesUnavailableError(HttpLib2Error): pass # Open Items: # ----------- # Proxy support # Are we removing the cached content too soon on PUT (only delete on 200 Maybe?) # Pluggable cache storage (supports storing the cache in # flat files by default. We need a plug-in architecture # that can support Berkeley DB and Squid) # == Known Issues == # Does not handle a resource that uses conneg and Last-Modified but no ETag as a cache validator. # Does not handle Cache-Control: max-stale # Does not use Age: headers when calculating cache freshness. # The number of redirections to follow before giving up. # Note that only GET redirects are automatically followed. # Will also honor 301 requests by saving that info and never # requesting that URI again. DEFAULT_MAX_REDIRECTS = 5 # Which headers are hop-by-hop headers by default HOP_BY_HOP = ['connection', 'keep-alive', 'proxy-authenticate', 'proxy-authorization', 'te', 'trailers', 'transfer-encoding', 'upgrade'] def _get_end2end_headers(response): hopbyhop = list(HOP_BY_HOP) hopbyhop.extend([x.strip() for x in response.get('connection', '').split(',')]) return [header for header in response.keys() if header not in hopbyhop] URI = re.compile(r"^(([^:/?#]+):)?(//([^/?#]*))?([^?#]*)(\?([^#]*))?(#(.*))?") def parse_uri(uri): """Parses a URI using the regex given in Appendix B of RFC 3986. (scheme, authority, path, query, fragment) = parse_uri(uri) """ groups = URI.match(uri).groups() return (groups[1], groups[3], groups[4], groups[6], groups[8]) def urlnorm(uri): (scheme, authority, path, query, fragment) = parse_uri(uri) if not scheme or not authority: raise RelativeURIError("Only absolute URIs are allowed. uri = %s" % uri) authority = authority.lower() scheme = scheme.lower() if not path: path = "/" # Could do syntax based normalization of the URI before # computing the digest. See Section 6.2.2 of Std 66. request_uri = query and "?".join([path, query]) or path scheme = scheme.lower() defrag_uri = scheme + "://" + authority + request_uri return scheme, authority, request_uri, defrag_uri # Cache filename construction (original borrowed from Venus http://intertwingly.net/code/venus/) re_url_scheme = re.compile(r'^\w+://') re_slash = re.compile(r'[?/:|]+') def safename(filename): """Return a filename suitable for the cache. Strips dangerous and common characters to create a filename we can use to store the cache in. """ try: if re_url_scheme.match(filename): if isinstance(filename,str): filename = filename.decode('utf-8') filename = filename.encode('idna') else: filename = filename.encode('idna') except UnicodeError: pass if isinstance(filename,unicode): filename=filename.encode('utf-8') filemd5 = _md5(filename).hexdigest() filename = re_url_scheme.sub("", filename) filename = re_slash.sub(",", filename) # limit length of filename if len(filename)>200: filename=filename[:200] return ",".join((filename, filemd5)) NORMALIZE_SPACE = re.compile(r'(?:\r\n)?[ \t]+') def _normalize_headers(headers): return dict([ (key.lower(), NORMALIZE_SPACE.sub(value, ' ').strip()) for (key, value) in headers.iteritems()]) def _parse_cache_control(headers): retval = {} if headers.has_key('cache-control'): parts = headers['cache-control'].split(',') parts_with_args = [tuple([x.strip().lower() for x in part.split("=", 1)]) for part in parts if -1 != part.find("=")] parts_wo_args = [(name.strip().lower(), 1) for name in parts if -1 == name.find("=")] retval = dict(parts_with_args + parts_wo_args) return retval # Whether to use a strict mode to parse WWW-Authenticate headers # Might lead to bad results in case of ill-formed header value, # so disabled by default, falling back to relaxed parsing. # Set to true to turn on, usefull for testing servers. USE_WWW_AUTH_STRICT_PARSING = 0 # In regex below: # [^\0-\x1f\x7f-\xff()<>@,;:\\\"/[\]?={} \t]+ matches a "token" as defined by HTTP # "(?:[^\0-\x08\x0A-\x1f\x7f-\xff\\\"]|\\[\0-\x7f])*?" matches a "quoted-string" as defined by HTTP, when LWS have already been replaced by a single space # Actually, as an auth-param value can be either a token or a quoted-string, they are combined in a single pattern which matches both: # \"?((?<=\")(?:[^\0-\x1f\x7f-\xff\\\"]|\\[\0-\x7f])*?(?=\")|(?<!\")[^\0-\x08\x0A-\x1f\x7f-\xff()<>@,;:\\\"/[\]?={} \t]+(?!\"))\"? WWW_AUTH_STRICT = re.compile(r"^(?:\s*(?:,\s*)?([^\0-\x1f\x7f-\xff()<>@,;:\\\"/[\]?={} \t]+)\s*=\s*\"?((?<=\")(?:[^\0-\x08\x0A-\x1f\x7f-\xff\\\"]|\\[\0-\x7f])*?(?=\")|(?<!\")[^\0-\x1f\x7f-\xff()<>@,;:\\\"/[\]?={} \t]+(?!\"))\"?)(.*)$") WWW_AUTH_RELAXED = re.compile(r"^(?:\s*(?:,\s*)?([^ \t\r\n=]+)\s*=\s*\"?((?<=\")(?:[^\\\"]|\\.)*?(?=\")|(?<!\")[^ \t\r\n,]+(?!\"))\"?)(.*)$") UNQUOTE_PAIRS = re.compile(r'\\(.)') def _parse_www_authenticate(headers, headername='www-authenticate'): """Returns a dictionary of dictionaries, one dict per auth_scheme.""" retval = {} if headers.has_key(headername): authenticate = headers[headername].strip() www_auth = USE_WWW_AUTH_STRICT_PARSING and WWW_AUTH_STRICT or WWW_AUTH_RELAXED while authenticate: # Break off the scheme at the beginning of the line if headername == 'authentication-info': (auth_scheme, the_rest) = ('digest', authenticate) else: (auth_scheme, the_rest) = authenticate.split(" ", 1) # Now loop over all the key value pairs that come after the scheme, # being careful not to roll into the next scheme match = www_auth.search(the_rest) auth_params = {} while match: if match and len(match.groups()) == 3: (key, value, the_rest) = match.groups() auth_params[key.lower()] = UNQUOTE_PAIRS.sub(r'\1', value) # '\\'.join([x.replace('\\', '') for x in value.split('\\\\')]) match = www_auth.search(the_rest) retval[auth_scheme.lower()] = auth_params authenticate = the_rest.strip() return retval def _entry_disposition(response_headers, request_headers): """Determine freshness from the Date, Expires and Cache-Control headers. We don't handle the following: 1. Cache-Control: max-stale 2. Age: headers are not used in the calculations. Not that this algorithm is simpler than you might think because we are operating as a private (non-shared) cache. This lets us ignore 's-maxage'. We can also ignore 'proxy-invalidate' since we aren't a proxy. We will never return a stale document as fresh as a design decision, and thus the non-implementation of 'max-stale'. This also lets us safely ignore 'must-revalidate' since we operate as if every server has sent 'must-revalidate'. Since we are private we get to ignore both 'public' and 'private' parameters. We also ignore 'no-transform' since we don't do any transformations. The 'no-store' parameter is handled at a higher level. So the only Cache-Control parameters we look at are: no-cache only-if-cached max-age min-fresh """ retval = "STALE" cc = _parse_cache_control(request_headers) cc_response = _parse_cache_control(response_headers) if request_headers.has_key('pragma') and request_headers['pragma'].lower().find('no-cache') != -1: retval = "TRANSPARENT" if 'cache-control' not in request_headers: request_headers['cache-control'] = 'no-cache' elif cc.has_key('no-cache'): retval = "TRANSPARENT" elif cc_response.has_key('no-cache'): retval = "STALE" elif cc.has_key('only-if-cached'): retval = "FRESH" elif response_headers.has_key('date'): date = calendar.timegm(email.Utils.parsedate_tz(response_headers['date'])) now = time.time() current_age = max(0, now - date) if cc_response.has_key('max-age'): try: freshness_lifetime = int(cc_response['max-age']) except ValueError: freshness_lifetime = 0 elif response_headers.has_key('expires'): expires = email.Utils.parsedate_tz(response_headers['expires']) if None == expires: freshness_lifetime = 0 else: freshness_lifetime = max(0, calendar.timegm(expires) - date) else: freshness_lifetime = 0 if cc.has_key('max-age'): try: freshness_lifetime = int(cc['max-age']) except ValueError: freshness_lifetime = 0 if cc.has_key('min-fresh'): try: min_fresh = int(cc['min-fresh']) except ValueError: min_fresh = 0 current_age += min_fresh if freshness_lifetime > current_age: retval = "FRESH" return retval def _decompressContent(response, new_content): content = new_content try: encoding = response.get('content-encoding', None) if encoding in ['gzip', 'deflate']: if encoding == 'gzip': content = gzip.GzipFile(fileobj=StringIO.StringIO(new_content)).read() if encoding == 'deflate': content = zlib.decompress(content) response['content-length'] = str(len(content)) # Record the historical presence of the encoding in a way the won't interfere. response['-content-encoding'] = response['content-encoding'] del response['content-encoding'] except IOError: content = "" raise FailedToDecompressContent(_("Content purported to be compressed with %s but failed to decompress.") % response.get('content-encoding'), response, content) return content def _updateCache(request_headers, response_headers, content, cache, cachekey): if cachekey: cc = _parse_cache_control(request_headers) cc_response = _parse_cache_control(response_headers) if cc.has_key('no-store') or cc_response.has_key('no-store'): cache.delete(cachekey) else: info = email.Message.Message() for key, value in response_headers.iteritems(): if key not in ['status','content-encoding','transfer-encoding']: info[key] = value # Add annotations to the cache to indicate what headers # are variant for this request. vary = response_headers.get('vary', None) if vary: vary_headers = vary.lower().replace(' ', '').split(',') for header in vary_headers: key = '-varied-%s' % header try: info[key] = request_headers[header] except KeyError: pass status = response_headers.status if status == 304: status = 200 status_header = 'status: %d\r\n' % response_headers.status header_str = info.as_string() header_str = re.sub("\r(?!\n)|(?<!\r)\n", "\r\n", header_str) text = "".join([status_header, header_str, content]) cache.set(cachekey, text) def _cnonce(): dig = _md5("%s:%s" % (time.ctime(), ["0123456789"[random.randrange(0, 9)] for i in range(20)])).hexdigest() return dig[:16] def _wsse_username_token(cnonce, iso_now, password): return base64.b64encode(_sha("%s%s%s" % (cnonce, iso_now, password)).digest()).strip() # For credentials we need two things, first # a pool of credential to try (not necesarily tied to BAsic, Digest, etc.) # Then we also need a list of URIs that have already demanded authentication # That list is tricky since sub-URIs can take the same auth, or the # auth scheme may change as you descend the tree. # So we also need each Auth instance to be able to tell us # how close to the 'top' it is. class Authentication(object): def __init__(self, credentials, host, request_uri, headers, response, content, http): (scheme, authority, path, query, fragment) = parse_uri(request_uri) self.path = path self.host = host self.credentials = credentials self.http = http def depth(self, request_uri): (scheme, authority, path, query, fragment) = parse_uri(request_uri) return request_uri[len(self.path):].count("/") def inscope(self, host, request_uri): # XXX Should we normalize the request_uri? (scheme, authority, path, query, fragment) = parse_uri(request_uri) return (host == self.host) and path.startswith(self.path) def request(self, method, request_uri, headers, content): """Modify the request headers to add the appropriate Authorization header. Over-rise this in sub-classes.""" pass def response(self, response, content): """Gives us a chance to update with new nonces or such returned from the last authorized response. Over-rise this in sub-classes if necessary. Return TRUE is the request is to be retried, for example Digest may return stale=true. """ return False class BasicAuthentication(Authentication): def __init__(self, credentials, host, request_uri, headers, response, content, http): Authentication.__init__(self, credentials, host, request_uri, headers, response, content, http) def request(self, method, request_uri, headers, content): """Modify the request headers to add the appropriate Authorization header.""" headers['authorization'] = 'Basic ' + base64.b64encode("%s:%s" % self.credentials).strip() class DigestAuthentication(Authentication): """Only do qop='auth' and MD5, since that is all Apache currently implements""" def __init__(self, credentials, host, request_uri, headers, response, content, http): Authentication.__init__(self, credentials, host, request_uri, headers, response, content, http) challenge = _parse_www_authenticate(response, 'www-authenticate') self.challenge = challenge['digest'] qop = self.challenge.get('qop', 'auth') self.challenge['qop'] = ('auth' in [x.strip() for x in qop.split()]) and 'auth' or None if self.challenge['qop'] is None: raise UnimplementedDigestAuthOptionError( _("Unsupported value for qop: %s." % qop)) self.challenge['algorithm'] = self.challenge.get('algorithm', 'MD5').upper() if self.challenge['algorithm'] != 'MD5': raise UnimplementedDigestAuthOptionError( _("Unsupported value for algorithm: %s." % self.challenge['algorithm'])) self.A1 = "".join([self.credentials[0], ":", self.challenge['realm'], ":", self.credentials[1]]) self.challenge['nc'] = 1 def request(self, method, request_uri, headers, content, cnonce = None): """Modify the request headers""" H = lambda x: _md5(x).hexdigest() KD = lambda s, d: H("%s:%s" % (s, d)) A2 = "".join([method, ":", request_uri]) self.challenge['cnonce'] = cnonce or _cnonce() request_digest = '"%s"' % KD(H(self.A1), "%s:%s:%s:%s:%s" % (self.challenge['nonce'], '%08x' % self.challenge['nc'], self.challenge['cnonce'], self.challenge['qop'], H(A2) )) headers['Authorization'] = 'Digest username="%s", realm="%s", nonce="%s", uri="%s", algorithm=%s, response=%s, qop=%s, nc=%08x, cnonce="%s"' % ( self.credentials[0], self.challenge['realm'], self.challenge['nonce'], request_uri, self.challenge['algorithm'], request_digest, self.challenge['qop'], self.challenge['nc'], self.challenge['cnonce'], ) self.challenge['nc'] += 1 def response(self, response, content): if not response.has_key('authentication-info'): challenge = _parse_www_authenticate(response, 'www-authenticate').get('digest', {}) if 'true' == challenge.get('stale'): self.challenge['nonce'] = challenge['nonce'] self.challenge['nc'] = 1 return True else: updated_challenge = _parse_www_authenticate(response, 'authentication-info').get('digest', {}) if updated_challenge.has_key('nextnonce'): self.challenge['nonce'] = updated_challenge['nextnonce'] self.challenge['nc'] = 1 return False class HmacDigestAuthentication(Authentication): """Adapted from Robert Sayre's code and DigestAuthentication above.""" __author__ = "Thomas Broyer (t.broyer@ltgt.net)" def __init__(self, credentials, host, request_uri, headers, response, content, http): Authentication.__init__(self, credentials, host, request_uri, headers, response, content, http) challenge = _parse_www_authenticate(response, 'www-authenticate') self.challenge = challenge['hmacdigest'] # TODO: self.challenge['domain'] self.challenge['reason'] = self.challenge.get('reason', 'unauthorized') if self.challenge['reason'] not in ['unauthorized', 'integrity']: self.challenge['reason'] = 'unauthorized' self.challenge['salt'] = self.challenge.get('salt', '') if not self.challenge.get('snonce'): raise UnimplementedHmacDigestAuthOptionError( _("The challenge doesn't contain a server nonce, or this one is empty.")) self.challenge['algorithm'] = self.challenge.get('algorithm', 'HMAC-SHA-1') if self.challenge['algorithm'] not in ['HMAC-SHA-1', 'HMAC-MD5']: raise UnimplementedHmacDigestAuthOptionError( _("Unsupported value for algorithm: %s." % self.challenge['algorithm'])) self.challenge['pw-algorithm'] = self.challenge.get('pw-algorithm', 'SHA-1') if self.challenge['pw-algorithm'] not in ['SHA-1', 'MD5']: raise UnimplementedHmacDigestAuthOptionError( _("Unsupported value for pw-algorithm: %s." % self.challenge['pw-algorithm'])) if self.challenge['algorithm'] == 'HMAC-MD5': self.hashmod = _md5 else: self.hashmod = _sha if self.challenge['pw-algorithm'] == 'MD5': self.pwhashmod = _md5 else: self.pwhashmod = _sha self.key = "".join([self.credentials[0], ":", self.pwhashmod.new("".join([self.credentials[1], self.challenge['salt']])).hexdigest().lower(), ":", self.challenge['realm'] ]) self.key = self.pwhashmod.new(self.key).hexdigest().lower() def request(self, method, request_uri, headers, content): """Modify the request headers""" keys = _get_end2end_headers(headers) keylist = "".join(["%s " % k for k in keys]) headers_val = "".join([headers[k] for k in keys]) created = time.strftime('%Y-%m-%dT%H:%M:%SZ',time.gmtime()) cnonce = _cnonce() request_digest = "%s:%s:%s:%s:%s" % (method, request_uri, cnonce, self.challenge['snonce'], headers_val) request_digest = hmac.new(self.key, request_digest, self.hashmod).hexdigest().lower() headers['Authorization'] = 'HMACDigest username="%s", realm="%s", snonce="%s", cnonce="%s", uri="%s", created="%s", response="%s", headers="%s"' % ( self.credentials[0], self.challenge['realm'], self.challenge['snonce'], cnonce, request_uri, created, request_digest, keylist, ) def response(self, response, content): challenge = _parse_www_authenticate(response, 'www-authenticate').get('hmacdigest', {}) if challenge.get('reason') in ['integrity', 'stale']: return True return False class WsseAuthentication(Authentication): """This is thinly tested and should not be relied upon. At this time there isn't any third party server to test against. Blogger and TypePad implemented this algorithm at one point but Blogger has since switched to Basic over HTTPS and TypePad has implemented it wrong, by never issuing a 401 challenge but instead requiring your client to telepathically know that their endpoint is expecting WSSE profile="UsernameToken".""" def __init__(self, credentials, host, request_uri, headers, response, content, http): Authentication.__init__(self, credentials, host, request_uri, headers, response, content, http) def request(self, method, request_uri, headers, content): """Modify the request headers to add the appropriate Authorization header.""" headers['Authorization'] = 'WSSE profile="UsernameToken"' iso_now = time.strftime("%Y-%m-%dT%H:%M:%SZ", time.gmtime()) cnonce = _cnonce() password_digest = _wsse_username_token(cnonce, iso_now, self.credentials[1]) headers['X-WSSE'] = 'UsernameToken Username="%s", PasswordDigest="%s", Nonce="%s", Created="%s"' % ( self.credentials[0], password_digest, cnonce, iso_now) class GoogleLoginAuthentication(Authentication): def __init__(self, credentials, host, request_uri, headers, response, content, http): from urllib import urlencode Authentication.__init__(self, credentials, host, request_uri, headers, response, content, http) challenge = _parse_www_authenticate(response, 'www-authenticate') service = challenge['googlelogin'].get('service', 'xapi') # Bloggger actually returns the service in the challenge # For the rest we guess based on the URI if service == 'xapi' and request_uri.find("calendar") > 0: service = "cl" # No point in guessing Base or Spreadsheet #elif request_uri.find("spreadsheets") > 0: # service = "wise" auth = dict(Email=credentials[0], Passwd=credentials[1], service=service, source=headers['user-agent']) resp, content = self.http.request("https://www.google.com/accounts/ClientLogin", method="POST", body=urlencode(auth), headers={'Content-Type': 'application/x-www-form-urlencoded'}) lines = content.split('\n') d = dict([tuple(line.split("=", 1)) for line in lines if line]) if resp.status == 403: self.Auth = "" else: self.Auth = d['Auth'] def request(self, method, request_uri, headers, content): """Modify the request headers to add the appropriate Authorization header.""" headers['authorization'] = 'GoogleLogin Auth=' + self.Auth AUTH_SCHEME_CLASSES = { "basic": BasicAuthentication, "wsse": WsseAuthentication, "digest": DigestAuthentication, "hmacdigest": HmacDigestAuthentication, "googlelogin": GoogleLoginAuthentication } AUTH_SCHEME_ORDER = ["hmacdigest", "googlelogin", "digest", "wsse", "basic"] class FileCache(object): """Uses a local directory as a store for cached files. Not really safe to use if multiple threads or processes are going to be running on the same cache. """ def __init__(self, cache, safe=safename): # use safe=lambda x: md5.new(x).hexdigest() for the old behavior self.cache = cache self.safe = safe if not os.path.exists(cache): os.makedirs(self.cache) def get(self, key): retval = None cacheFullPath = os.path.join(self.cache, self.safe(key)) try: f = file(cacheFullPath, "rb") retval = f.read() f.close() except IOError: pass return retval def set(self, key, value): cacheFullPath = os.path.join(self.cache, self.safe(key)) f = file(cacheFullPath, "wb") f.write(value) f.close() def delete(self, key): cacheFullPath = os.path.join(self.cache, self.safe(key)) if os.path.exists(cacheFullPath): os.remove(cacheFullPath) class Credentials(object): def __init__(self): self.credentials = [] def add(self, name, password, domain=""): self.credentials.append((domain.lower(), name, password)) def clear(self): self.credentials = [] def iter(self, domain): for (cdomain, name, password) in self.credentials: if cdomain == "" or domain == cdomain: yield (name, password) class KeyCerts(Credentials): """Identical to Credentials except that name/password are mapped to key/cert.""" pass class ProxyInfo(object): """Collect information required to use a proxy.""" def __init__(self, proxy_type, proxy_host, proxy_port, proxy_rdns=None, proxy_user=None, proxy_pass=None): """The parameter proxy_type must be set to one of socks.PROXY_TYPE_XXX constants. For example: p = ProxyInfo(proxy_type=socks.PROXY_TYPE_HTTP, proxy_host='localhost', proxy_port=8000) """ self.proxy_type, self.proxy_host, self.proxy_port, self.proxy_rdns, self.proxy_user, self.proxy_pass = proxy_type, proxy_host, proxy_port, proxy_rdns, proxy_user, proxy_pass def astuple(self): return (self.proxy_type, self.proxy_host, self.proxy_port, self.proxy_rdns, self.proxy_user, self.proxy_pass) def isgood(self): return (self.proxy_host != None) and (self.proxy_port != None) class HTTPConnectionWithTimeout(httplib.HTTPConnection): """HTTPConnection subclass that supports timeouts""" def __init__(self, host, port=None, strict=None, timeout=None, proxy_info=None): httplib.HTTPConnection.__init__(self, host, port, strict) self.timeout = timeout self.proxy_info = proxy_info def connect(self): """Connect to the host and port specified in __init__.""" # Mostly verbatim from httplib.py. if self.proxy_info and socks is None: raise ProxiesUnavailableError( 'Proxy support missing but proxy use was requested!') msg = "getaddrinfo returns an empty list" for res in socket.getaddrinfo(self.host, self.port, 0, socket.SOCK_STREAM): af, socktype, proto, canonname, sa = res try: if self.proxy_info and self.proxy_info.isgood(): self.sock = socks.socksocket(af, socktype, proto) self.sock.setproxy(*self.proxy_info.astuple()) else: self.sock = socket.socket(af, socktype, proto) self.sock.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1) # Different from httplib: support timeouts. if has_timeout(self.timeout): self.sock.settimeout(self.timeout) # End of difference from httplib. if self.debuglevel > 0: print "connect: (%s, %s)" % (self.host, self.port) self.sock.connect(sa) except socket.error, msg: if self.debuglevel > 0: print 'connect fail:', (self.host, self.port) if self.sock: self.sock.close() self.sock = None continue break if not self.sock: raise socket.error, msg class HTTPSConnectionWithTimeout(httplib.HTTPSConnection): "This class allows communication via SSL." def __init__(self, host, port=None, key_file=None, cert_file=None, strict=None, timeout=None, proxy_info=None): httplib.HTTPSConnection.__init__(self, host, port=port, key_file=key_file, cert_file=cert_file, strict=strict) self.timeout = timeout self.proxy_info = proxy_info def connect(self): "Connect to a host on a given (SSL) port." if self.proxy_info and self.proxy_info.isgood(): sock = socks.socksocket(socket.AF_INET, socket.SOCK_STREAM) sock.setproxy(*self.proxy_info.astuple()) else: sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) sock.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1) if has_timeout(self.timeout): sock.settimeout(self.timeout) sock.connect((self.host, self.port)) self.sock =_ssl_wrap_socket(sock, self.key_file, self.cert_file) class Http(object): """An HTTP client that handles: - all methods - caching - ETags - compression, - HTTPS - Basic - Digest - WSSE and more. """ def __init__(self, cache=None, timeout=None, proxy_info=None): """The value of proxy_info is a ProxyInfo instance. If 'cache' is a string then it is used as a directory name for a disk cache. Otherwise it must be an object that supports the same interface as FileCache.""" self.proxy_info = proxy_info # Map domain name to an httplib connection self.connections = {} # The location of the cache, for now a directory # where cached responses are held. if cache and isinstance(cache, str): self.cache = FileCache(cache) else: self.cache = cache # Name/password self.credentials = Credentials() # Key/cert self.certificates = KeyCerts() # authorization objects self.authorizations = [] # If set to False then no redirects are followed, even safe ones. self.follow_redirects = True # Which HTTP methods do we apply optimistic concurrency to, i.e. # which methods get an "if-match:" etag header added to them. self.optimistic_concurrency_methods = ["PUT"] # If 'follow_redirects' is True, and this is set to True then # all redirecs are followed, including unsafe ones. self.follow_all_redirects = False self.ignore_etag = False self.force_exception_to_status_code = False self.timeout = timeout def _auth_from_challenge(self, host, request_uri, headers, response, content): """A generator that creates Authorization objects that can be applied to requests. """ challenges = _parse_www_authenticate(response, 'www-authenticate') for cred in self.credentials.iter(host): for scheme in AUTH_SCHEME_ORDER: if challenges.has_key(scheme): yield AUTH_SCHEME_CLASSES[scheme](cred, host, request_uri, headers, response, content, self) def add_credentials(self, name, password, domain=""): """Add a name and password that will be used any time a request requires authentication.""" self.credentials.add(name, password, domain) def add_certificate(self, key, cert, domain): """Add a key and cert that will be used any time a request requires authentication.""" self.certificates.add(key, cert, domain) def clear_credentials(self): """Remove all the names and passwords that are used for authentication""" self.credentials.clear() self.authorizations = [] def _conn_request(self, conn, request_uri, method, body, headers): for i in range(2): try: conn.request(method, request_uri, body, headers) except socket.gaierror: conn.close() raise ServerNotFoundError("Unable to find the server at %s" % conn.host) except socket.error, e: if e.errno == errno.ECONNREFUSED: # Connection refused raise except httplib.HTTPException: # Just because the server closed the connection doesn't apparently mean # that the server didn't send a response. pass try: response = conn.getresponse() except (socket.error, httplib.HTTPException): if i == 0: conn.close() conn.connect() continue else: raise else: content = "" if method == "HEAD": response.close() else: content = response.read() response = Response(response) if method != "HEAD": content = _decompressContent(response, content) break return (response, content) def _request(self, conn, host, absolute_uri, request_uri, method, body, headers, redirections, cachekey): """Do the actual request using the connection object and also follow one level of redirects if necessary""" auths = [(auth.depth(request_uri), auth) for auth in self.authorizations if auth.inscope(host, request_uri)] auth = auths and sorted(auths)[0][1] or None if auth: auth.request(method, request_uri, headers, body) (response, content) = self._conn_request(conn, request_uri, method, body, headers) if auth: if auth.response(response, body): auth.request(method, request_uri, headers, body) (response, content) = self._conn_request(conn, request_uri, method, body, headers ) response._stale_digest = 1 if response.status == 401: for authorization in self._auth_from_challenge(host, request_uri, headers, response, content): authorization.request(method, request_uri, headers, body) (response, content) = self._conn_request(conn, request_uri, method, body, headers, ) if response.status != 401: self.authorizations.append(authorization) authorization.response(response, body) break if (self.follow_all_redirects or (method in ["GET", "HEAD"]) or response.status == 303): if self.follow_redirects and response.status in [300, 301, 302, 303, 307]: # Pick out the location header and basically start from the beginning # remembering first to strip the ETag header and decrement our 'depth' if redirections: if not response.has_key('location') and response.status != 300: raise RedirectMissingLocation( _("Redirected but the response is missing a Location: header."), response, content) # Fix-up relative redirects (which violate an RFC 2616 MUST) if response.has_key('location'): location = response['location'] (scheme, authority, path, query, fragment) = parse_uri(location) if authority == None: response['location'] = urlparse.urljoin(absolute_uri, location) if response.status == 301 and method in ["GET", "HEAD"]: response['-x-permanent-redirect-url'] = response['location'] if not response.has_key('content-location'): response['content-location'] = absolute_uri _updateCache(headers, response, content, self.cache, cachekey) if headers.has_key('if-none-match'): del headers['if-none-match'] if headers.has_key('if-modified-since'): del headers['if-modified-since'] if response.has_key('location'): location = response['location'] old_response = copy.deepcopy(response) if not old_response.has_key('content-location'): old_response['content-location'] = absolute_uri redirect_method = ((response.status == 303) and (method not in ["GET", "HEAD"])) and "GET" or method (response, content) = self.request(location, redirect_method, body=body, headers = headers, redirections = redirections - 1) response.previous = old_response else: raise RedirectLimit( _("Redirected more times than rediection_limit allows."), response, content) elif response.status in [200, 203] and method == "GET": # Don't cache 206's since we aren't going to handle byte range requests if not response.has_key('content-location'): response['content-location'] = absolute_uri _updateCache(headers, response, content, self.cache, cachekey) return (response, content) def _normalize_headers(self, headers): return _normalize_headers(headers) # Need to catch and rebrand some exceptions # Then need to optionally turn all exceptions into status codes # including all socket.* and httplib.* exceptions. def request(self, uri, method="GET", body=None, headers=None, redirections=DEFAULT_MAX_REDIRECTS, connection_type=None): """ Performs a single HTTP request. The 'uri' is the URI of the HTTP resource and can begin with either 'http' or 'https'. The value of 'uri' must be an absolute URI. The 'method' is the HTTP method to perform, such as GET, POST, DELETE, etc. There is no restriction on the methods allowed. The 'body' is the entity body to be sent with the request. It is a string object. Any extra headers that are to be sent with the request should be provided in the 'headers' dictionary. The maximum number of redirect to follow before raising an exception is 'redirections. The default is 5. The return value is a tuple of (response, content), the first being and instance of the 'Response' class, the second being a string that contains the response entity body. """ try: if headers is None: headers = {} else: headers = self._normalize_headers(headers) if not headers.has_key('user-agent'): headers['user-agent'] = "Python-httplib2/%s" % __version__ uri = iri2uri(uri) (scheme, authority, request_uri, defrag_uri) = urlnorm(uri) domain_port = authority.split(":")[0:2] if len(domain_port) == 2 and domain_port[1] == '443' and scheme == 'http': scheme = 'https' authority = domain_port[0] conn_key = scheme+":"+authority if conn_key in self.connections: conn = self.connections[conn_key] else: if not connection_type: connection_type = (scheme == 'https') and HTTPSConnectionWithTimeout or HTTPConnectionWithTimeout certs = list(self.certificates.iter(authority)) if scheme == 'https' and certs: conn = self.connections[conn_key] = connection_type(authority, key_file=certs[0][0], cert_file=certs[0][1], timeout=self.timeout, proxy_info=self.proxy_info) else: conn = self.connections[conn_key] = connection_type(authority, timeout=self.timeout, proxy_info=self.proxy_info) conn.set_debuglevel(debuglevel) if method in ["GET", "HEAD"] and 'range' not in headers and 'accept-encoding' not in headers: headers['accept-encoding'] = 'gzip, deflate' info = email.Message.Message() cached_value = None if self.cache: cachekey = defrag_uri cached_value = self.cache.get(cachekey) if cached_value: # info = email.message_from_string(cached_value) # # Need to replace the line above with the kludge below # to fix the non-existent bug not fixed in this # bug report: http://mail.python.org/pipermail/python-bugs-list/2005-September/030289.html try: info, content = cached_value.split('\r\n\r\n', 1) feedparser = email.FeedParser.FeedParser() feedparser.feed(info) info = feedparser.close() feedparser._parse = None except IndexError: self.cache.delete(cachekey) cachekey = None cached_value = None else: cachekey = None if method in self.optimistic_concurrency_methods and self.cache and info.has_key('etag') and not self.ignore_etag and 'if-match' not in headers: # http://www.w3.org/1999/04/Editing/ headers['if-match'] = info['etag'] if method not in ["GET", "HEAD"] and self.cache and cachekey: # RFC 2616 Section 13.10 self.cache.delete(cachekey) # Check the vary header in the cache to see if this request # matches what varies in the cache. if method in ['GET', 'HEAD'] and 'vary' in info: vary = info['vary'] vary_headers = vary.lower().replace(' ', '').split(',') for header in vary_headers: key = '-varied-%s' % header value = info[key] if headers.get(header, None) != value: cached_value = None break if cached_value and method in ["GET", "HEAD"] and self.cache and 'range' not in headers: if info.has_key('-x-permanent-redirect-url'): # Should cached permanent redirects be counted in our redirection count? For now, yes. (response, new_content) = self.request(info['-x-permanent-redirect-url'], "GET", headers = headers, redirections = redirections - 1) response.previous = Response(info) response.previous.fromcache = True else: # Determine our course of action: # Is the cached entry fresh or stale? # Has the client requested a non-cached response? # # There seems to be three possible answers: # 1. [FRESH] Return the cache entry w/o doing a GET # 2. [STALE] Do the GET (but add in cache validators if available) # 3. [TRANSPARENT] Do a GET w/o any cache validators (Cache-Control: no-cache) on the request entry_disposition = _entry_disposition(info, headers) if entry_disposition == "FRESH": if not cached_value: info['status'] = '504' content = "" response = Response(info) if cached_value: response.fromcache = True return (response, content) if entry_disposition == "STALE": if info.has_key('etag') and not self.ignore_etag and not 'if-none-match' in headers: headers['if-none-match'] = info['etag'] if info.has_key('last-modified') and not 'last-modified' in headers: headers['if-modified-since'] = info['last-modified'] elif entry_disposition == "TRANSPARENT": pass (response, new_content) = self._request(conn, authority, uri, request_uri, method, body, headers, redirections, cachekey) if response.status == 304 and method == "GET": # Rewrite the cache entry with the new end-to-end headers # Take all headers that are in response # and overwrite their values in info. # unless they are hop-by-hop, or are listed in the connection header. for key in _get_end2end_headers(response): info[key] = response[key] merged_response = Response(info) if hasattr(response, "_stale_digest"): merged_response._stale_digest = response._stale_digest _updateCache(headers, merged_response, content, self.cache, cachekey) response = merged_response response.status = 200 response.fromcache = True elif response.status == 200: content = new_content else: self.cache.delete(cachekey) content = new_content else: cc = _parse_cache_control(headers) if cc.has_key('only-if-cached'): info['status'] = '504' response = Response(info) content = "" else: (response, content) = self._request(conn, authority, uri, request_uri, method, body, headers, redirections, cachekey) except Exception, e: if self.force_exception_to_status_code: if isinstance(e, HttpLib2ErrorWithResponse): response = e.response content = e.content response.status = 500 response.reason = str(e) elif isinstance(e, socket.timeout): content = "Request Timeout" response = Response( { "content-type": "text/plain", "status": "408", "content-length": len(content) }) response.reason = "Request Timeout" else: content = str(e) response = Response( { "content-type": "text/plain", "status": "400", "content-length": len(content) }) response.reason = "Bad Request" else: raise return (response, content) class Response(dict): """An object more like email.Message than httplib.HTTPResponse.""" """Is this response from our local cache""" fromcache = False """HTTP protocol version used by server. 10 for HTTP/1.0, 11 for HTTP/1.1. """ version = 11 "Status code returned by server. " status = 200 """Reason phrase returned by server.""" reason = "Ok" previous = None def __init__(self, info): # info is either an email.Message or # an httplib.HTTPResponse object. if isinstance(info, httplib.HTTPResponse): for key, value in info.getheaders(): self[key.lower()] = value self.status = info.status self['status'] = str(self.status) self.reason = info.reason self.version = info.version elif isinstance(info, email.Message.Message): for key, value in info.items(): self[key] = value self.status = int(self['status']) else: for key, value in info.iteritems(): self[key] = value self.status = int(self.get('status', self.status)) def __getattr__(self, name): if name == 'dict': return self else: raise AttributeError, name
Python
#!/usr/bin/env python # Copyright (c) 2007, Google Inc. # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. # # --- # Author: Chad Lester # Design and style contributions by: # Amit Patel, Bogdan Cocosel, Daniel Dulitz, Eric Tiedemann, # Eric Veach, Laurence Gonsalves, Matthew Springer # Code reorganized a bit by Craig Silverstein """This module is used to define and parse command line flags. This module defines a *distributed* flag-definition policy: rather than an application having to define all flags in or near main(), each python module defines flags that are useful to it. When one python module imports another, it gains access to the other's flags. (This is implemented by having all modules share a common, global registry object containing all the flag information.) Flags are defined through the use of one of the DEFINE_xxx functions. The specific function used determines how the flag is parsed, checked, and optionally type-converted, when it's seen on the command line. IMPLEMENTATION: DEFINE_* creates a 'Flag' object and registers it with a 'FlagValues' object (typically the global FlagValues FLAGS, defined here). The 'FlagValues' object can scan the command line arguments and pass flag arguments to the corresponding 'Flag' objects for value-checking and type conversion. The converted flag values are available as attributes of the 'FlagValues' object. Code can access the flag through a FlagValues object, for instance gflags.FLAGS.myflag. Typically, the __main__ module passes the command line arguments to gflags.FLAGS for parsing. At bottom, this module calls getopt(), so getopt functionality is supported, including short- and long-style flags, and the use of -- to terminate flags. Methods defined by the flag module will throw 'FlagsError' exceptions. The exception argument will be a human-readable string. FLAG TYPES: This is a list of the DEFINE_*'s that you can do. All flags take a name, default value, help-string, and optional 'short' name (one-letter name). Some flags have other arguments, which are described with the flag. DEFINE_string: takes any input, and interprets it as a string. DEFINE_bool or DEFINE_boolean: typically does not take an argument: say --myflag to set FLAGS.myflag to true, or --nomyflag to set FLAGS.myflag to false. Alternately, you can say --myflag=true or --myflag=t or --myflag=1 or --myflag=false or --myflag=f or --myflag=0 DEFINE_float: takes an input and interprets it as a floating point number. Takes optional args lower_bound and upper_bound; if the number specified on the command line is out of range, it will raise a FlagError. DEFINE_integer: takes an input and interprets it as an integer. Takes optional args lower_bound and upper_bound as for floats. DEFINE_enum: takes a list of strings which represents legal values. If the command-line value is not in this list, raise a flag error. Otherwise, assign to FLAGS.flag as a string. DEFINE_list: Takes a comma-separated list of strings on the commandline. Stores them in a python list object. DEFINE_spaceseplist: Takes a space-separated list of strings on the commandline. Stores them in a python list object. Example: --myspacesepflag "foo bar baz" DEFINE_multistring: The same as DEFINE_string, except the flag can be specified more than once on the commandline. The result is a python list object (list of strings), even if the flag is only on the command line once. DEFINE_multi_int: The same as DEFINE_integer, except the flag can be specified more than once on the commandline. The result is a python list object (list of ints), even if the flag is only on the command line once. SPECIAL FLAGS: There are a few flags that have special meaning: --help prints a list of all the flags in a human-readable fashion --helpshort prints a list of all key flags (see below). --helpxml prints a list of all flags, in XML format. DO NOT parse the output of --help and --helpshort. Instead, parse the output of --helpxml. For more info, see "OUTPUT FOR --helpxml" below. --flagfile=foo read flags from file foo. --undefok=f1,f2 ignore unrecognized option errors for f1,f2. For boolean flags, you should use --undefok=boolflag, and --boolflag and --noboolflag will be accepted. Do not use --undefok=noboolflag. -- as in getopt(), terminates flag-processing FLAGS VALIDATORS: If your program: - requires flag X to be specified - needs flag Y to match a regular expression - or requires any more general constraint to be satisfied then validators are for you! Each validator represents a constraint over one flag, which is enforced starting from the initial parsing of the flags and until the program terminates. Also, lower_bound and upper_bound for numerical flags are enforced using flag validators. Howto: If you want to enforce a constraint over one flag, use flags.RegisterValidator(flag_name, checker, message='Flag validation failed', flag_values=FLAGS) After flag values are initially parsed, and after any change to the specified flag, method checker(flag_value) will be executed. If constraint is not satisfied, an IllegalFlagValue exception will be raised. See RegisterValidator's docstring for a detailed explanation on how to construct your own checker. EXAMPLE USAGE: FLAGS = flags.FLAGS flags.DEFINE_integer('my_version', 0, 'Version number.') flags.DEFINE_string('filename', None, 'Input file name', short_name='f') flags.RegisterValidator('my_version', lambda value: value % 2 == 0, message='--my_version must be divisible by 2') flags.MarkFlagAsRequired('filename') NOTE ON --flagfile: Flags may be loaded from text files in addition to being specified on the commandline. Any flags you don't feel like typing, throw them in a file, one flag per line, for instance: --myflag=myvalue --nomyboolean_flag You then specify your file with the special flag '--flagfile=somefile'. You CAN recursively nest flagfile= tokens OR use multiple files on the command line. Lines beginning with a single hash '#' or a double slash '//' are comments in your flagfile. Any flagfile=<file> will be interpreted as having a relative path from the current working directory rather than from the place the file was included from: myPythonScript.py --flagfile=config/somefile.cfg If somefile.cfg includes further --flagfile= directives, these will be referenced relative to the original CWD, not from the directory the including flagfile was found in! The caveat applies to people who are including a series of nested files in a different dir than they are executing out of. Relative path names are always from CWD, not from the directory of the parent include flagfile. We do now support '~' expanded directory names. Absolute path names ALWAYS work! EXAMPLE USAGE: import gflags FLAGS = gflags.FLAGS # Flag names are globally defined! So in general, we need to be # careful to pick names that are unlikely to be used by other libraries. # If there is a conflict, we'll get an error at import time. gflags.DEFINE_string('name', 'Mr. President', 'your name') gflags.DEFINE_integer('age', None, 'your age in years', lower_bound=0) gflags.DEFINE_boolean('debug', False, 'produces debugging output') gflags.DEFINE_enum('gender', 'male', ['male', 'female'], 'your gender') def main(argv): try: argv = FLAGS(argv) # parse flags except gflags.FlagsError, e: print '%s\\nUsage: %s ARGS\\n%s' % (e, sys.argv[0], FLAGS) sys.exit(1) if FLAGS.debug: print 'non-flag arguments:', argv print 'Happy Birthday', FLAGS.name if FLAGS.age is not None: print 'You are a %s, who is %d years old' % (FLAGS.gender, FLAGS.age) if __name__ == '__main__': main(sys.argv) KEY FLAGS: As we already explained, each module gains access to all flags defined by all the other modules it transitively imports. In the case of non-trivial scripts, this means a lot of flags ... For documentation purposes, it is good to identify the flags that are key (i.e., really important) to a module. Clearly, the concept of "key flag" is a subjective one. When trying to determine whether a flag is key to a module or not, assume that you are trying to explain your module to a potential user: which flags would you really like to mention first? We'll describe shortly how to declare which flags are key to a module. For the moment, assume we know the set of key flags for each module. Then, if you use the app.py module, you can use the --helpshort flag to print only the help for the flags that are key to the main module, in a human-readable format. NOTE: If you need to parse the flag help, do NOT use the output of --help / --helpshort. That output is meant for human consumption, and may be changed in the future. Instead, use --helpxml; flags that are key for the main module are marked there with a <key>yes</key> element. The set of key flags for a module M is composed of: 1. Flags defined by module M by calling a DEFINE_* function. 2. Flags that module M explictly declares as key by using the function DECLARE_key_flag(<flag_name>) 3. Key flags of other modules that M specifies by using the function ADOPT_module_key_flags(<other_module>) This is a "bulk" declaration of key flags: each flag that is key for <other_module> becomes key for the current module too. Notice that if you do not use the functions described at points 2 and 3 above, then --helpshort prints information only about the flags defined by the main module of our script. In many cases, this behavior is good enough. But if you move part of the main module code (together with the related flags) into a different module, then it is nice to use DECLARE_key_flag / ADOPT_module_key_flags and make sure --helpshort lists all relevant flags (otherwise, your code refactoring may confuse your users). Note: each of DECLARE_key_flag / ADOPT_module_key_flags has its own pluses and minuses: DECLARE_key_flag is more targeted and may lead a more focused --helpshort documentation. ADOPT_module_key_flags is good for cases when an entire module is considered key to the current script. Also, it does not require updates to client scripts when a new flag is added to the module. EXAMPLE USAGE 2 (WITH KEY FLAGS): Consider an application that contains the following three files (two auxiliary modules and a main module): File libfoo.py: import gflags gflags.DEFINE_integer('num_replicas', 3, 'Number of replicas to start') gflags.DEFINE_boolean('rpc2', True, 'Turn on the usage of RPC2.') ... some code ... File libbar.py: import gflags gflags.DEFINE_string('bar_gfs_path', '/gfs/path', 'Path to the GFS files for libbar.') gflags.DEFINE_string('email_for_bar_errors', 'bar-team@google.com', 'Email address for bug reports about module libbar.') gflags.DEFINE_boolean('bar_risky_hack', False, 'Turn on an experimental and buggy optimization.') ... some code ... File myscript.py: import gflags import libfoo import libbar gflags.DEFINE_integer('num_iterations', 0, 'Number of iterations.') # Declare that all flags that are key for libfoo are # key for this module too. gflags.ADOPT_module_key_flags(libfoo) # Declare that the flag --bar_gfs_path (defined in libbar) is key # for this module. gflags.DECLARE_key_flag('bar_gfs_path') ... some code ... When myscript is invoked with the flag --helpshort, the resulted help message lists information about all the key flags for myscript: --num_iterations, --num_replicas, --rpc2, and --bar_gfs_path (in addition to the special flags --help and --helpshort). Of course, myscript uses all the flags declared by it (in this case, just --num_replicas) or by any of the modules it transitively imports (e.g., the modules libfoo, libbar). E.g., it can access the value of FLAGS.bar_risky_hack, even if --bar_risky_hack is not declared as a key flag for myscript. OUTPUT FOR --helpxml: The --helpxml flag generates output with the following structure: <?xml version="1.0"?> <AllFlags> <program>PROGRAM_BASENAME</program> <usage>MAIN_MODULE_DOCSTRING</usage> (<flag> [<key>yes</key>] <file>DECLARING_MODULE</file> <name>FLAG_NAME</name> <meaning>FLAG_HELP_MESSAGE</meaning> <default>DEFAULT_FLAG_VALUE</default> <current>CURRENT_FLAG_VALUE</current> <type>FLAG_TYPE</type> [OPTIONAL_ELEMENTS] </flag>)* </AllFlags> Notes: 1. The output is intentionally similar to the output generated by the C++ command-line flag library. The few differences are due to the Python flags that do not have a C++ equivalent (at least not yet), e.g., DEFINE_list. 2. New XML elements may be added in the future. 3. DEFAULT_FLAG_VALUE is in serialized form, i.e., the string you can pass for this flag on the command-line. E.g., for a flag defined using DEFINE_list, this field may be foo,bar, not ['foo', 'bar']. 4. CURRENT_FLAG_VALUE is produced using str(). This means that the string 'false' will be represented in the same way as the boolean False. Using repr() would have removed this ambiguity and simplified parsing, but would have broken the compatibility with the C++ command-line flags. 5. OPTIONAL_ELEMENTS describe elements relevant for certain kinds of flags: lower_bound, upper_bound (for flags that specify bounds), enum_value (for enum flags), list_separator (for flags that consist of a list of values, separated by a special token). 6. We do not provide any example here: please use --helpxml instead. """ import cgi import getopt import os import re import string import sys import gflags_validators # Are we running at least python 2.2? try: if tuple(sys.version_info[:3]) < (2,2,0): raise NotImplementedError("requires python 2.2.0 or later") except AttributeError: # a very old python, that lacks sys.version_info raise NotImplementedError("requires python 2.2.0 or later") # If we're not running at least python 2.2.1, define True, False, and bool. # Thanks, Guido, for the code. try: True, False, bool except NameError: False = 0 True = 1 def bool(x): if x: return True else: return False # Are we running under pychecker? _RUNNING_PYCHECKER = 'pychecker.python' in sys.modules def _GetCallingModule(): """Returns the name of the module that's calling into this module. We generally use this function to get the name of the module calling a DEFINE_foo... function. """ # Walk down the stack to find the first globals dict that's not ours. for depth in range(1, sys.getrecursionlimit()): if not sys._getframe(depth).f_globals is globals(): globals_for_frame = sys._getframe(depth).f_globals module_name = _GetModuleObjectAndName(globals_for_frame)[1] if module_name is not None: return module_name raise AssertionError("No module was found") def _GetThisModuleObjectAndName(): """Returns: (module object, module name) for this module.""" return _GetModuleObjectAndName(globals()) # module exceptions: class FlagsError(Exception): """The base class for all flags errors.""" pass class DuplicateFlag(FlagsError): """Raised if there is a flag naming conflict.""" pass class DuplicateFlagCannotPropagateNoneToSwig(DuplicateFlag): """Special case of DuplicateFlag -- SWIG flag value can't be set to None. This can be raised when a duplicate flag is created. Even if allow_override is True, we still abort if the new value is None, because it's currently impossible to pass None default value back to SWIG. See FlagValues.SetDefault for details. """ pass # A DuplicateFlagError conveys more information than a # DuplicateFlag. Since there are external modules that create # DuplicateFlags, the interface to DuplicateFlag shouldn't change. class DuplicateFlagError(DuplicateFlag): def __init__(self, flagname, flag_values): self.flagname = flagname message = "The flag '%s' is defined twice." % self.flagname flags_by_module = flag_values.FlagsByModuleDict() for module in flags_by_module: for flag in flags_by_module[module]: if flag.name == flagname or flag.short_name == flagname: message = message + " First from " + module + "," break message = message + " Second from " + _GetCallingModule() DuplicateFlag.__init__(self, message) class IllegalFlagValue(FlagsError): """The flag command line argument is illegal.""" pass class UnrecognizedFlag(FlagsError): """Raised if a flag is unrecognized.""" pass # An UnrecognizedFlagError conveys more information than an UnrecognizedFlag. # Since there are external modules that create DuplicateFlags, the interface to # DuplicateFlag shouldn't change. The flagvalue will be assigned the full value # of the flag and its argument, if any, allowing handling of unrecognzed flags # in an exception handler. # If flagvalue is the empty string, then this exception is an due to a # reference to a flag that was not already defined. class UnrecognizedFlagError(UnrecognizedFlag): def __init__(self, flagname, flagvalue=''): self.flagname = flagname self.flagvalue = flagvalue UnrecognizedFlag.__init__( self, "Unknown command line flag '%s'" % flagname) # Global variable used by expvar _exported_flags = {} _help_width = 80 # width of help output def GetHelpWidth(): """Returns: an integer, the width of help lines that is used in TextWrap.""" return _help_width def CutCommonSpacePrefix(text): """Removes a common space prefix from the lines of a multiline text. If the first line does not start with a space, it is left as it is and only in the remaining lines a common space prefix is being searched for. That means the first line will stay untouched. This is especially useful to turn doc strings into help texts. This is because some people prefer to have the doc comment start already after the apostrophy and then align the following lines while others have the apostrophies on a seperately line. The function also drops trailing empty lines and ignores empty lines following the initial content line while calculating the initial common whitespace. Args: text: text to work on Returns: the resulting text """ text_lines = text.splitlines() # Drop trailing empty lines while text_lines and not text_lines[-1]: text_lines = text_lines[:-1] if text_lines: # We got some content, is the first line starting with a space? if text_lines[0] and text_lines[0][0].isspace(): text_first_line = [] else: text_first_line = [text_lines.pop(0)] # Calculate length of common leading whitesppace (only over content lines) common_prefix = os.path.commonprefix([line for line in text_lines if line]) space_prefix_len = len(common_prefix) - len(common_prefix.lstrip()) # If we have a common space prefix, drop it from all lines if space_prefix_len: for index in xrange(len(text_lines)): if text_lines[index]: text_lines[index] = text_lines[index][space_prefix_len:] return '\n'.join(text_first_line + text_lines) return '' def TextWrap(text, length=None, indent='', firstline_indent=None, tabs=' '): """Wraps a given text to a maximum line length and returns it. We turn lines that only contain whitespaces into empty lines. We keep new lines and tabs (e.g., we do not treat tabs as spaces). Args: text: text to wrap length: maximum length of a line, includes indentation if this is None then use GetHelpWidth() indent: indent for all but first line firstline_indent: indent for first line; if None, fall back to indent tabs: replacement for tabs Returns: wrapped text Raises: FlagsError: if indent not shorter than length FlagsError: if firstline_indent not shorter than length """ # Get defaults where callee used None if length is None: length = GetHelpWidth() if indent is None: indent = '' if len(indent) >= length: raise FlagsError('Indent must be shorter than length') # In line we will be holding the current line which is to be started # with indent (or firstline_indent if available) and then appended # with words. if firstline_indent is None: firstline_indent = '' line = indent else: line = firstline_indent if len(firstline_indent) >= length: raise FlagsError('First iline indent must be shorter than length') # If the callee does not care about tabs we simply convert them to # spaces If callee wanted tabs to be single space then we do that # already here. if not tabs or tabs == ' ': text = text.replace('\t', ' ') else: tabs_are_whitespace = not tabs.strip() line_regex = re.compile('([ ]*)(\t*)([^ \t]+)', re.MULTILINE) # Split the text into lines and the lines with the regex above. The # resulting lines are collected in result[]. For each split we get the # spaces, the tabs and the next non white space (e.g. next word). result = [] for text_line in text.splitlines(): # Store result length so we can find out whether processing the next # line gave any new content old_result_len = len(result) # Process next line with line_regex. For optimization we do an rstrip(). # - process tabs (changes either line or word, see below) # - process word (first try to squeeze on line, then wrap or force wrap) # Spaces found on the line are ignored, they get added while wrapping as # needed. for spaces, current_tabs, word in line_regex.findall(text_line.rstrip()): # If tabs weren't converted to spaces, handle them now if current_tabs: # If the last thing we added was a space anyway then drop # it. But let's not get rid of the indentation. if (((result and line != indent) or (not result and line != firstline_indent)) and line[-1] == ' '): line = line[:-1] # Add the tabs, if that means adding whitespace, just add it at # the line, the rstrip() code while shorten the line down if # necessary if tabs_are_whitespace: line += tabs * len(current_tabs) else: # if not all tab replacement is whitespace we prepend it to the word word = tabs * len(current_tabs) + word # Handle the case where word cannot be squeezed onto current last line if len(line) + len(word) > length and len(indent) + len(word) <= length: result.append(line.rstrip()) line = indent + word word = '' # No space left on line or can we append a space? if len(line) + 1 >= length: result.append(line.rstrip()) line = indent else: line += ' ' # Add word and shorten it up to allowed line length. Restart next # line with indent and repeat, or add a space if we're done (word # finished) This deals with words that caanot fit on one line # (e.g. indent + word longer than allowed line length). while len(line) + len(word) >= length: line += word result.append(line[:length]) word = line[length:] line = indent # Default case, simply append the word and a space if word: line += word + ' ' # End of input line. If we have content we finish the line. If the # current line is just the indent but we had content in during this # original line then we need to add an emoty line. if (result and line != indent) or (not result and line != firstline_indent): result.append(line.rstrip()) elif len(result) == old_result_len: result.append('') line = indent return '\n'.join(result) def DocToHelp(doc): """Takes a __doc__ string and reformats it as help.""" # Get rid of starting and ending white space. Using lstrip() or even # strip() could drop more than maximum of first line and right space # of last line. doc = doc.strip() # Get rid of all empty lines whitespace_only_line = re.compile('^[ \t]+$', re.M) doc = whitespace_only_line.sub('', doc) # Cut out common space at line beginnings doc = CutCommonSpacePrefix(doc) # Just like this module's comment, comments tend to be aligned somehow. # In other words they all start with the same amount of white space # 1) keep double new lines # 2) keep ws after new lines if not empty line # 3) all other new lines shall be changed to a space # Solution: Match new lines between non white space and replace with space. doc = re.sub('(?<=\S)\n(?=\S)', ' ', doc, re.M) return doc def _GetModuleObjectAndName(globals_dict): """Returns the module that defines a global environment, and its name. Args: globals_dict: A dictionary that should correspond to an environment providing the values of the globals. Returns: A pair consisting of (1) module object and (2) module name (a string). Returns (None, None) if the module could not be identified. """ # The use of .items() (instead of .iteritems()) is NOT a mistake: if # a parallel thread imports a module while we iterate over # .iteritems() (not nice, but possible), we get a RuntimeError ... # Hence, we use the slightly slower but safer .items(). for name, module in sys.modules.items(): if getattr(module, '__dict__', None) is globals_dict: if name == '__main__': # Pick a more informative name for the main module. name = sys.argv[0] return (module, name) return (None, None) def _GetMainModule(): """Returns the name of the module from which execution started.""" for depth in range(1, sys.getrecursionlimit()): try: globals_of_main = sys._getframe(depth).f_globals except ValueError: return _GetModuleObjectAndName(globals_of_main)[1] raise AssertionError("No module was found") class FlagValues: """Registry of 'Flag' objects. A 'FlagValues' can then scan command line arguments, passing flag arguments through to the 'Flag' objects that it owns. It also provides easy access to the flag values. Typically only one 'FlagValues' object is needed by an application: gflags.FLAGS This class is heavily overloaded: 'Flag' objects are registered via __setitem__: FLAGS['longname'] = x # register a new flag The .value attribute of the registered 'Flag' objects can be accessed as attributes of this 'FlagValues' object, through __getattr__. Both the long and short name of the original 'Flag' objects can be used to access its value: FLAGS.longname # parsed flag value FLAGS.x # parsed flag value (short name) Command line arguments are scanned and passed to the registered 'Flag' objects through the __call__ method. Unparsed arguments, including argv[0] (e.g. the program name) are returned. argv = FLAGS(sys.argv) # scan command line arguments The original registered Flag objects can be retrieved through the use of the dictionary-like operator, __getitem__: x = FLAGS['longname'] # access the registered Flag object The str() operator of a 'FlagValues' object provides help for all of the registered 'Flag' objects. """ def __init__(self): # Since everything in this class is so heavily overloaded, the only # way of defining and using fields is to access __dict__ directly. # Dictionary: flag name (string) -> Flag object. self.__dict__['__flags'] = {} # Dictionary: module name (string) -> list of Flag objects that are defined # by that module. self.__dict__['__flags_by_module'] = {} # Dictionary: module name (string) -> list of Flag objects that are # key for that module. self.__dict__['__key_flags_by_module'] = {} # Set if we should use new style gnu_getopt rather than getopt when parsing # the args. Only possible with Python 2.3+ self.UseGnuGetOpt(False) def UseGnuGetOpt(self, use_gnu_getopt=True): self.__dict__['__use_gnu_getopt'] = use_gnu_getopt def IsGnuGetOpt(self): return self.__dict__['__use_gnu_getopt'] def FlagDict(self): return self.__dict__['__flags'] def FlagsByModuleDict(self): """Returns the dictionary of module_name -> list of defined flags. Returns: A dictionary. Its keys are module names (strings). Its values are lists of Flag objects. """ return self.__dict__['__flags_by_module'] def KeyFlagsByModuleDict(self): """Returns the dictionary of module_name -> list of key flags. Returns: A dictionary. Its keys are module names (strings). Its values are lists of Flag objects. """ return self.__dict__['__key_flags_by_module'] def _RegisterFlagByModule(self, module_name, flag): """Records the module that defines a specific flag. We keep track of which flag is defined by which module so that we can later sort the flags by module. Args: module_name: A string, the name of a Python module. flag: A Flag object, a flag that is key to the module. """ flags_by_module = self.FlagsByModuleDict() flags_by_module.setdefault(module_name, []).append(flag) def _RegisterKeyFlagForModule(self, module_name, flag): """Specifies that a flag is a key flag for a module. Args: module_name: A string, the name of a Python module. flag: A Flag object, a flag that is key to the module. """ key_flags_by_module = self.KeyFlagsByModuleDict() # The list of key flags for the module named module_name. key_flags = key_flags_by_module.setdefault(module_name, []) # Add flag, but avoid duplicates. if flag not in key_flags: key_flags.append(flag) def _GetFlagsDefinedByModule(self, module): """Returns the list of flags defined by a module. Args: module: A module object or a module name (a string). Returns: A new list of Flag objects. Caller may update this list as he wishes: none of those changes will affect the internals of this FlagValue object. """ if not isinstance(module, str): module = module.__name__ return list(self.FlagsByModuleDict().get(module, [])) def _GetKeyFlagsForModule(self, module): """Returns the list of key flags for a module. Args: module: A module object or a module name (a string) Returns: A new list of Flag objects. Caller may update this list as he wishes: none of those changes will affect the internals of this FlagValue object. """ if not isinstance(module, str): module = module.__name__ # Any flag is a key flag for the module that defined it. NOTE: # key_flags is a fresh list: we can update it without affecting the # internals of this FlagValues object. key_flags = self._GetFlagsDefinedByModule(module) # Take into account flags explicitly declared as key for a module. for flag in self.KeyFlagsByModuleDict().get(module, []): if flag not in key_flags: key_flags.append(flag) return key_flags def AppendFlagValues(self, flag_values): """Appends flags registered in another FlagValues instance. Args: flag_values: registry to copy from """ for flag_name, flag in flag_values.FlagDict().iteritems(): # Each flags with shortname appears here twice (once under its # normal name, and again with its short name). To prevent # problems (DuplicateFlagError) with double flag registration, we # perform a check to make sure that the entry we're looking at is # for its normal name. if flag_name == flag.name: self[flag_name] = flag def RemoveFlagValues(self, flag_values): """Remove flags that were previously appended from another FlagValues. Args: flag_values: registry containing flags to remove. """ for flag_name in flag_values.FlagDict(): self.__delattr__(flag_name) def __setitem__(self, name, flag): """Registers a new flag variable.""" fl = self.FlagDict() if not isinstance(flag, Flag): raise IllegalFlagValue(flag) if not isinstance(name, type("")): raise FlagsError("Flag name must be a string") if len(name) == 0: raise FlagsError("Flag name cannot be empty") # If running under pychecker, duplicate keys are likely to be # defined. Disable check for duplicate keys when pycheck'ing. if (fl.has_key(name) and not flag.allow_override and not fl[name].allow_override and not _RUNNING_PYCHECKER): raise DuplicateFlagError(name, self) short_name = flag.short_name if short_name is not None: if (fl.has_key(short_name) and not flag.allow_override and not fl[short_name].allow_override and not _RUNNING_PYCHECKER): raise DuplicateFlagError(short_name, self) fl[short_name] = flag fl[name] = flag global _exported_flags _exported_flags[name] = flag def __getitem__(self, name): """Retrieves the Flag object for the flag --name.""" return self.FlagDict()[name] def __getattr__(self, name): """Retrieves the 'value' attribute of the flag --name.""" fl = self.FlagDict() if not fl.has_key(name): raise AttributeError(name) return fl[name].value def __setattr__(self, name, value): """Sets the 'value' attribute of the flag --name.""" fl = self.FlagDict() fl[name].value = value self._AssertValidators(fl[name].validators) return value def _AssertAllValidators(self): all_validators = set() for flag in self.FlagDict().itervalues(): for validator in flag.validators: all_validators.add(validator) self._AssertValidators(all_validators) def _AssertValidators(self, validators): """Assert if all validators in the list are satisfied. Asserts validators in the order they were created. Args: validators: Iterable(gflags_validators.Validator), validators to be verified Raises: AttributeError: if validators work with a non-existing flag. IllegalFlagValue: if validation fails for at least one validator """ for validator in sorted( validators, key=lambda validator: validator.insertion_index): try: validator.Verify(self) except gflags_validators.Error, e: message = validator.PrintFlagsWithValues(self) raise IllegalFlagValue('%s: %s' % (message, str(e))) def _FlagIsRegistered(self, flag_obj): """Checks whether a Flag object is registered under some name. Note: this is non trivial: in addition to its normal name, a flag may have a short name too. In self.FlagDict(), both the normal and the short name are mapped to the same flag object. E.g., calling only "del FLAGS.short_name" is not unregistering the corresponding Flag object (it is still registered under the longer name). Args: flag_obj: A Flag object. Returns: A boolean: True iff flag_obj is registered under some name. """ flag_dict = self.FlagDict() # Check whether flag_obj is registered under its long name. name = flag_obj.name if flag_dict.get(name, None) == flag_obj: return True # Check whether flag_obj is registered under its short name. short_name = flag_obj.short_name if (short_name is not None and flag_dict.get(short_name, None) == flag_obj): return True # The flag cannot be registered under any other name, so we do not # need to do a full search through the values of self.FlagDict(). return False def __delattr__(self, flag_name): """Deletes a previously-defined flag from a flag object. This method makes sure we can delete a flag by using del flag_values_object.<flag_name> E.g., flags.DEFINE_integer('foo', 1, 'Integer flag.') del flags.FLAGS.foo Args: flag_name: A string, the name of the flag to be deleted. Raises: AttributeError: When there is no registered flag named flag_name. """ fl = self.FlagDict() if flag_name not in fl: raise AttributeError(flag_name) flag_obj = fl[flag_name] del fl[flag_name] if not self._FlagIsRegistered(flag_obj): # If the Flag object indicated by flag_name is no longer # registered (please see the docstring of _FlagIsRegistered), then # we delete the occurences of the flag object in all our internal # dictionaries. self.__RemoveFlagFromDictByModule(self.FlagsByModuleDict(), flag_obj) self.__RemoveFlagFromDictByModule(self.KeyFlagsByModuleDict(), flag_obj) def __RemoveFlagFromDictByModule(self, flags_by_module_dict, flag_obj): """Removes a flag object from a module -> list of flags dictionary. Args: flags_by_module_dict: A dictionary that maps module names to lists of flags. flag_obj: A flag object. """ for unused_module, flags_in_module in flags_by_module_dict.iteritems(): # while (as opposed to if) takes care of multiple occurences of a # flag in the list for the same module. while flag_obj in flags_in_module: flags_in_module.remove(flag_obj) def SetDefault(self, name, value): """Changes the default value of the named flag object.""" fl = self.FlagDict() if not fl.has_key(name): raise AttributeError(name) fl[name].SetDefault(value) self._AssertValidators(fl[name].validators) def __contains__(self, name): """Returns True if name is a value (flag) in the dict.""" return name in self.FlagDict() has_key = __contains__ # a synonym for __contains__() def __iter__(self): return self.FlagDict().iterkeys() def __call__(self, argv): """Parses flags from argv; stores parsed flags into this FlagValues object. All unparsed arguments are returned. Flags are parsed using the GNU Program Argument Syntax Conventions, using getopt: http://www.gnu.org/software/libc/manual/html_mono/libc.html#Getopt Args: argv: argument list. Can be of any type that may be converted to a list. Returns: The list of arguments not parsed as options, including argv[0] Raises: FlagsError: on any parsing error """ # Support any sequence type that can be converted to a list argv = list(argv) shortopts = "" longopts = [] fl = self.FlagDict() # This pre parses the argv list for --flagfile=<> options. argv = argv[:1] + self.ReadFlagsFromFiles(argv[1:], force_gnu=False) # Correct the argv to support the google style of passing boolean # parameters. Boolean parameters may be passed by using --mybool, # --nomybool, --mybool=(true|false|1|0). getopt does not support # having options that may or may not have a parameter. We replace # instances of the short form --mybool and --nomybool with their # full forms: --mybool=(true|false). original_argv = list(argv) # list() makes a copy shortest_matches = None for name, flag in fl.items(): if not flag.boolean: continue if shortest_matches is None: # Determine the smallest allowable prefix for all flag names shortest_matches = self.ShortestUniquePrefixes(fl) no_name = 'no' + name prefix = shortest_matches[name] no_prefix = shortest_matches[no_name] # Replace all occurences of this boolean with extended forms for arg_idx in range(1, len(argv)): arg = argv[arg_idx] if arg.find('=') >= 0: continue if arg.startswith('--'+prefix) and ('--'+name).startswith(arg): argv[arg_idx] = ('--%s=true' % name) elif arg.startswith('--'+no_prefix) and ('--'+no_name).startswith(arg): argv[arg_idx] = ('--%s=false' % name) # Loop over all of the flags, building up the lists of short options # and long options that will be passed to getopt. Short options are # specified as a string of letters, each letter followed by a colon # if it takes an argument. Long options are stored in an array of # strings. Each string ends with an '=' if it takes an argument. for name, flag in fl.items(): longopts.append(name + "=") if len(name) == 1: # one-letter option: allow short flag type also shortopts += name if not flag.boolean: shortopts += ":" longopts.append('undefok=') undefok_flags = [] # In case --undefok is specified, loop to pick up unrecognized # options one by one. unrecognized_opts = [] args = argv[1:] while True: try: if self.__dict__['__use_gnu_getopt']: optlist, unparsed_args = getopt.gnu_getopt(args, shortopts, longopts) else: optlist, unparsed_args = getopt.getopt(args, shortopts, longopts) break except getopt.GetoptError, e: if not e.opt or e.opt in fl: # Not an unrecognized option, reraise the exception as a FlagsError raise FlagsError(e) # Remove offender from args and try again for arg_index in range(len(args)): if ((args[arg_index] == '--' + e.opt) or (args[arg_index] == '-' + e.opt) or (args[arg_index].startswith('--' + e.opt + '='))): unrecognized_opts.append((e.opt, args[arg_index])) args = args[0:arg_index] + args[arg_index+1:] break else: # We should have found the option, so we don't expect to get # here. We could assert, but raising the original exception # might work better. raise FlagsError(e) for name, arg in optlist: if name == '--undefok': flag_names = arg.split(',') undefok_flags.extend(flag_names) # For boolean flags, if --undefok=boolflag is specified, then we should # also accept --noboolflag, in addition to --boolflag. # Since we don't know the type of the undefok'd flag, this will affect # non-boolean flags as well. # NOTE: You shouldn't use --undefok=noboolflag, because then we will # accept --nonoboolflag here. We are choosing not to do the conversion # from noboolflag -> boolflag because of the ambiguity that flag names # can start with 'no'. undefok_flags.extend('no' + name for name in flag_names) continue if name.startswith('--'): # long option name = name[2:] short_option = 0 else: # short option name = name[1:] short_option = 1 if fl.has_key(name): flag = fl[name] if flag.boolean and short_option: arg = 1 flag.Parse(arg) # If there were unrecognized options, raise an exception unless # the options were named via --undefok. for opt, value in unrecognized_opts: if opt not in undefok_flags: raise UnrecognizedFlagError(opt, value) if unparsed_args: if self.__dict__['__use_gnu_getopt']: # if using gnu_getopt just return the program name + remainder of argv. ret_val = argv[:1] + unparsed_args else: # unparsed_args becomes the first non-flag detected by getopt to # the end of argv. Because argv may have been modified above, # return original_argv for this region. ret_val = argv[:1] + original_argv[-len(unparsed_args):] else: ret_val = argv[:1] self._AssertAllValidators() return ret_val def Reset(self): """Resets the values to the point before FLAGS(argv) was called.""" for f in self.FlagDict().values(): f.Unparse() def RegisteredFlags(self): """Returns: a list of the names and short names of all registered flags.""" return self.FlagDict().keys() def FlagValuesDict(self): """Returns: a dictionary that maps flag names to flag values.""" flag_values = {} for flag_name in self.RegisteredFlags(): flag = self.FlagDict()[flag_name] flag_values[flag_name] = flag.value return flag_values def __str__(self): """Generates a help string for all known flags.""" return self.GetHelp() def GetHelp(self, prefix=''): """Generates a help string for all known flags.""" helplist = [] flags_by_module = self.FlagsByModuleDict() if flags_by_module: modules = flags_by_module.keys() modules.sort() # Print the help for the main module first, if possible. main_module = _GetMainModule() if main_module in modules: modules.remove(main_module) modules = [main_module] + modules for module in modules: self.__RenderOurModuleFlags(module, helplist) self.__RenderModuleFlags('gflags', _SPECIAL_FLAGS.FlagDict().values(), helplist) else: # Just print one long list of flags. self.__RenderFlagList( self.FlagDict().values() + _SPECIAL_FLAGS.FlagDict().values(), helplist, prefix) return '\n'.join(helplist) def __RenderModuleFlags(self, module, flags, output_lines, prefix=""): """Generates a help string for a given module.""" if not isinstance(module, str): module = module.__name__ output_lines.append('\n%s%s:' % (prefix, module)) self.__RenderFlagList(flags, output_lines, prefix + " ") def __RenderOurModuleFlags(self, module, output_lines, prefix=""): """Generates a help string for a given module.""" flags = self._GetFlagsDefinedByModule(module) if flags: self.__RenderModuleFlags(module, flags, output_lines, prefix) def __RenderOurModuleKeyFlags(self, module, output_lines, prefix=""): """Generates a help string for the key flags of a given module. Args: module: A module object or a module name (a string). output_lines: A list of strings. The generated help message lines will be appended to this list. prefix: A string that is prepended to each generated help line. """ key_flags = self._GetKeyFlagsForModule(module) if key_flags: self.__RenderModuleFlags(module, key_flags, output_lines, prefix) def ModuleHelp(self, module): """Describe the key flags of a module. Args: module: A module object or a module name (a string). Returns: string describing the key flags of a module. """ helplist = [] self.__RenderOurModuleKeyFlags(module, helplist) return '\n'.join(helplist) def MainModuleHelp(self): """Describe the key flags of the main module. Returns: string describing the key flags of a module. """ return self.ModuleHelp(_GetMainModule()) def __RenderFlagList(self, flaglist, output_lines, prefix=" "): fl = self.FlagDict() special_fl = _SPECIAL_FLAGS.FlagDict() flaglist = [(flag.name, flag) for flag in flaglist] flaglist.sort() flagset = {} for (name, flag) in flaglist: # It's possible this flag got deleted or overridden since being # registered in the per-module flaglist. Check now against the # canonical source of current flag information, the FlagDict. if fl.get(name, None) != flag and special_fl.get(name, None) != flag: # a different flag is using this name now continue # only print help once if flagset.has_key(flag): continue flagset[flag] = 1 flaghelp = "" if flag.short_name: flaghelp += "-%s," % flag.short_name if flag.boolean: flaghelp += "--[no]%s" % flag.name + ":" else: flaghelp += "--%s" % flag.name + ":" flaghelp += " " if flag.help: flaghelp += flag.help flaghelp = TextWrap(flaghelp, indent=prefix+" ", firstline_indent=prefix) if flag.default_as_str: flaghelp += "\n" flaghelp += TextWrap("(default: %s)" % flag.default_as_str, indent=prefix+" ") if flag.parser.syntactic_help: flaghelp += "\n" flaghelp += TextWrap("(%s)" % flag.parser.syntactic_help, indent=prefix+" ") output_lines.append(flaghelp) def get(self, name, default): """Returns the value of a flag (if not None) or a default value. Args: name: A string, the name of a flag. default: Default value to use if the flag value is None. """ value = self.__getattr__(name) if value is not None: # Can't do if not value, b/c value might be '0' or "" return value else: return default def ShortestUniquePrefixes(self, fl): """Returns: dictionary; maps flag names to their shortest unique prefix.""" # Sort the list of flag names sorted_flags = [] for name, flag in fl.items(): sorted_flags.append(name) if flag.boolean: sorted_flags.append('no%s' % name) sorted_flags.sort() # For each name in the sorted list, determine the shortest unique # prefix by comparing itself to the next name and to the previous # name (the latter check uses cached info from the previous loop). shortest_matches = {} prev_idx = 0 for flag_idx in range(len(sorted_flags)): curr = sorted_flags[flag_idx] if flag_idx == (len(sorted_flags) - 1): next = None else: next = sorted_flags[flag_idx+1] next_len = len(next) for curr_idx in range(len(curr)): if (next is None or curr_idx >= next_len or curr[curr_idx] != next[curr_idx]): # curr longer than next or no more chars in common shortest_matches[curr] = curr[:max(prev_idx, curr_idx) + 1] prev_idx = curr_idx break else: # curr shorter than (or equal to) next shortest_matches[curr] = curr prev_idx = curr_idx + 1 # next will need at least one more char return shortest_matches def __IsFlagFileDirective(self, flag_string): """Checks whether flag_string contain a --flagfile=<foo> directive.""" if isinstance(flag_string, type("")): if flag_string.startswith('--flagfile='): return 1 elif flag_string == '--flagfile': return 1 elif flag_string.startswith('-flagfile='): return 1 elif flag_string == '-flagfile': return 1 else: return 0 return 0 def ExtractFilename(self, flagfile_str): """Returns filename from a flagfile_str of form -[-]flagfile=filename. The cases of --flagfile foo and -flagfile foo shouldn't be hitting this function, as they are dealt with in the level above this function. """ if flagfile_str.startswith('--flagfile='): return os.path.expanduser((flagfile_str[(len('--flagfile=')):]).strip()) elif flagfile_str.startswith('-flagfile='): return os.path.expanduser((flagfile_str[(len('-flagfile=')):]).strip()) else: raise FlagsError('Hit illegal --flagfile type: %s' % flagfile_str) def __GetFlagFileLines(self, filename, parsed_file_list): """Returns the useful (!=comments, etc) lines from a file with flags. Args: filename: A string, the name of the flag file. parsed_file_list: A list of the names of the files we have already read. MUTATED BY THIS FUNCTION. Returns: List of strings. See the note below. NOTE(springer): This function checks for a nested --flagfile=<foo> tag and handles the lower file recursively. It returns a list of all the lines that _could_ contain command flags. This is EVERYTHING except whitespace lines and comments (lines starting with '#' or '//'). """ line_list = [] # All line from flagfile. flag_line_list = [] # Subset of lines w/o comments, blanks, flagfile= tags. try: file_obj = open(filename, 'r') except IOError, e_msg: print e_msg print 'ERROR:: Unable to open flagfile: %s' % (filename) return flag_line_list line_list = file_obj.readlines() file_obj.close() parsed_file_list.append(filename) # This is where we check each line in the file we just read. for line in line_list: if line.isspace(): pass # Checks for comment (a line that starts with '#'). elif line.startswith('#') or line.startswith('//'): pass # Checks for a nested "--flagfile=<bar>" flag in the current file. # If we find one, recursively parse down into that file. elif self.__IsFlagFileDirective(line): sub_filename = self.ExtractFilename(line) # We do a little safety check for reparsing a file we've already done. if not sub_filename in parsed_file_list: included_flags = self.__GetFlagFileLines(sub_filename, parsed_file_list) flag_line_list.extend(included_flags) else: # Case of hitting a circularly included file. print >>sys.stderr, ('Warning: Hit circular flagfile dependency: %s' % sub_filename) else: # Any line that's not a comment or a nested flagfile should get # copied into 2nd position. This leaves earlier arguements # further back in the list, thus giving them higher priority. flag_line_list.append(line.strip()) return flag_line_list def ReadFlagsFromFiles(self, argv, force_gnu=True): """Processes command line args, but also allow args to be read from file. Args: argv: A list of strings, usually sys.argv[1:], which may contain one or more flagfile directives of the form --flagfile="./filename". Note that the name of the program (sys.argv[0]) should be omitted. force_gnu: If False, --flagfile parsing obeys normal flag semantics. If True, --flagfile parsing instead follows gnu_getopt semantics. *** WARNING *** force_gnu=False may become the future default! Returns: A new list which has the original list combined with what we read from any flagfile(s). References: Global gflags.FLAG class instance. This function should be called before the normal FLAGS(argv) call. This function scans the input list for a flag that looks like: --flagfile=<somefile>. Then it opens <somefile>, reads all valid key and value pairs and inserts them into the input list between the first item of the list and any subsequent items in the list. Note that your application's flags are still defined the usual way using gflags DEFINE_flag() type functions. Notes (assuming we're getting a commandline of some sort as our input): --> Flags from the command line argv _should_ always take precedence! --> A further "--flagfile=<otherfile.cfg>" CAN be nested in a flagfile. It will be processed after the parent flag file is done. --> For duplicate flags, first one we hit should "win". --> In a flagfile, a line beginning with # or // is a comment. --> Entirely blank lines _should_ be ignored. """ parsed_file_list = [] rest_of_args = argv new_argv = [] while rest_of_args: current_arg = rest_of_args[0] rest_of_args = rest_of_args[1:] if self.__IsFlagFileDirective(current_arg): # This handles the case of -(-)flagfile foo. In this case the # next arg really is part of this one. if current_arg == '--flagfile' or current_arg == '-flagfile': if not rest_of_args: raise IllegalFlagValue('--flagfile with no argument') flag_filename = os.path.expanduser(rest_of_args[0]) rest_of_args = rest_of_args[1:] else: # This handles the case of (-)-flagfile=foo. flag_filename = self.ExtractFilename(current_arg) new_argv[0:0] = self.__GetFlagFileLines(flag_filename, parsed_file_list) else: new_argv.append(current_arg) # Stop parsing after '--', like getopt and gnu_getopt. if current_arg == '--': break # Stop parsing after a non-flag, like getopt. if not current_arg.startswith('-'): if not force_gnu and not self.__dict__['__use_gnu_getopt']: break if rest_of_args: new_argv.extend(rest_of_args) return new_argv def FlagsIntoString(self): """Returns a string with the flags assignments from this FlagValues object. This function ignores flags whose value is None. Each flag assignment is separated by a newline. NOTE: MUST mirror the behavior of the C++ function CommandlineFlagsIntoString from google3/base/commandlineflags.cc. """ s = '' for flag in self.FlagDict().values(): if flag.value is not None: s += flag.Serialize() + '\n' return s def AppendFlagsIntoFile(self, filename): """Appends all flags assignments from this FlagInfo object to a file. Output will be in the format of a flagfile. NOTE: MUST mirror the behavior of the C++ version of AppendFlagsIntoFile from google3/base/commandlineflags.cc. """ out_file = open(filename, 'a') out_file.write(self.FlagsIntoString()) out_file.close() def WriteHelpInXMLFormat(self, outfile=None): """Outputs flag documentation in XML format. NOTE: We use element names that are consistent with those used by the C++ command-line flag library, from google3/base/commandlineflags_reporting.cc. We also use a few new elements (e.g., <key>), but we do not interfere / overlap with existing XML elements used by the C++ library. Please maintain this consistency. Args: outfile: File object we write to. Default None means sys.stdout. """ outfile = outfile or sys.stdout outfile.write('<?xml version=\"1.0\"?>\n') outfile.write('<AllFlags>\n') indent = ' ' _WriteSimpleXMLElement(outfile, 'program', os.path.basename(sys.argv[0]), indent) usage_doc = sys.modules['__main__'].__doc__ if not usage_doc: usage_doc = '\nUSAGE: %s [flags]\n' % sys.argv[0] else: usage_doc = usage_doc.replace('%s', sys.argv[0]) _WriteSimpleXMLElement(outfile, 'usage', usage_doc, indent) # Get list of key flags for the main module. key_flags = self._GetKeyFlagsForModule(_GetMainModule()) # Sort flags by declaring module name and next by flag name. flags_by_module = self.FlagsByModuleDict() all_module_names = list(flags_by_module.keys()) all_module_names.sort() for module_name in all_module_names: flag_list = [(f.name, f) for f in flags_by_module[module_name]] flag_list.sort() for unused_flag_name, flag in flag_list: is_key = flag in key_flags flag.WriteInfoInXMLFormat(outfile, module_name, is_key=is_key, indent=indent) outfile.write('</AllFlags>\n') outfile.flush() def AddValidator(self, validator): """Register new flags validator to be checked. Args: validator: gflags_validators.Validator Raises: AttributeError: if validators work with a non-existing flag. """ for flag_name in validator.GetFlagsNames(): flag = self.FlagDict()[flag_name] flag.validators.append(validator) # end of FlagValues definition # The global FlagValues instance FLAGS = FlagValues() def _MakeXMLSafe(s): """Escapes <, >, and & from s, and removes XML 1.0-illegal chars.""" s = cgi.escape(s) # Escape <, >, and & # Remove characters that cannot appear in an XML 1.0 document # (http://www.w3.org/TR/REC-xml/#charsets). # # NOTE: if there are problems with current solution, one may move to # XML 1.1, which allows such chars, if they're entity-escaped (&#xHH;). s = re.sub(r'[\x00-\x08\x0b\x0c\x0e-\x1f]', '', s) return s def _WriteSimpleXMLElement(outfile, name, value, indent): """Writes a simple XML element. Args: outfile: File object we write the XML element to. name: A string, the name of XML element. value: A Python object, whose string representation will be used as the value of the XML element. indent: A string, prepended to each line of generated output. """ value_str = str(value) if isinstance(value, bool): # Display boolean values as the C++ flag library does: no caps. value_str = value_str.lower() outfile.write('%s<%s>%s</%s>\n' % (indent, name, _MakeXMLSafe(value_str), name)) class Flag: """Information about a command-line flag. 'Flag' objects define the following fields: .name - the name for this flag .default - the default value for this flag .default_as_str - default value as repr'd string, e.g., "'true'" (or None) .value - the most recent parsed value of this flag; set by Parse() .help - a help string or None if no help is available .short_name - the single letter alias for this flag (or None) .boolean - if 'true', this flag does not accept arguments .present - true if this flag was parsed from command line flags. .parser - an ArgumentParser object .serializer - an ArgumentSerializer object .allow_override - the flag may be redefined without raising an error The only public method of a 'Flag' object is Parse(), but it is typically only called by a 'FlagValues' object. The Parse() method is a thin wrapper around the 'ArgumentParser' Parse() method. The parsed value is saved in .value, and the .present attribute is updated. If this flag was already present, a FlagsError is raised. Parse() is also called during __init__ to parse the default value and initialize the .value attribute. This enables other python modules to safely use flags even if the __main__ module neglects to parse the command line arguments. The .present attribute is cleared after __init__ parsing. If the default value is set to None, then the __init__ parsing step is skipped and the .value attribute is initialized to None. Note: The default value is also presented to the user in the help string, so it is important that it be a legal value for this flag. """ def __init__(self, parser, serializer, name, default, help_string, short_name=None, boolean=0, allow_override=0): self.name = name if not help_string: help_string = '(no help available)' self.help = help_string self.short_name = short_name self.boolean = boolean self.present = 0 self.parser = parser self.serializer = serializer self.allow_override = allow_override self.value = None self.validators = [] self.SetDefault(default) def __GetParsedValueAsString(self, value): if value is None: return None if self.serializer: return repr(self.serializer.Serialize(value)) if self.boolean: if value: return repr('true') else: return repr('false') return repr(str(value)) def Parse(self, argument): try: self.value = self.parser.Parse(argument) except ValueError, e: # recast ValueError as IllegalFlagValue raise IllegalFlagValue("flag --%s=%s: %s" % (self.name, argument, e)) self.present += 1 def Unparse(self): if self.default is None: self.value = None else: self.Parse(self.default) self.present = 0 def Serialize(self): if self.value is None: return '' if self.boolean: if self.value: return "--%s" % self.name else: return "--no%s" % self.name else: if not self.serializer: raise FlagsError("Serializer not present for flag %s" % self.name) return "--%s=%s" % (self.name, self.serializer.Serialize(self.value)) def SetDefault(self, value): """Changes the default value (and current value too) for this Flag.""" # We can't allow a None override because it may end up not being # passed to C++ code when we're overriding C++ flags. So we # cowardly bail out until someone fixes the semantics of trying to # pass None to a C++ flag. See swig_flags.Init() for details on # this behavior. # TODO(olexiy): Users can directly call this method, bypassing all flags # validators (we don't have FlagValues here, so we can not check # validators). # The simplest solution I see is to make this method private. # Another approach would be to store reference to the corresponding # FlagValues with each flag, but this seems to be an overkill. if value is None and self.allow_override: raise DuplicateFlagCannotPropagateNoneToSwig(self.name) self.default = value self.Unparse() self.default_as_str = self.__GetParsedValueAsString(self.value) def Type(self): """Returns: a string that describes the type of this Flag.""" # NOTE: we use strings, and not the types.*Type constants because # our flags can have more exotic types, e.g., 'comma separated list # of strings', 'whitespace separated list of strings', etc. return self.parser.Type() def WriteInfoInXMLFormat(self, outfile, module_name, is_key=False, indent=''): """Writes common info about this flag, in XML format. This is information that is relevant to all flags (e.g., name, meaning, etc.). If you defined a flag that has some other pieces of info, then please override _WriteCustomInfoInXMLFormat. Please do NOT override this method. Args: outfile: File object we write to. module_name: A string, the name of the module that defines this flag. is_key: A boolean, True iff this flag is key for main module. indent: A string that is prepended to each generated line. """ outfile.write(indent + '<flag>\n') inner_indent = indent + ' ' if is_key: _WriteSimpleXMLElement(outfile, 'key', 'yes', inner_indent) _WriteSimpleXMLElement(outfile, 'file', module_name, inner_indent) # Print flag features that are relevant for all flags. _WriteSimpleXMLElement(outfile, 'name', self.name, inner_indent) if self.short_name: _WriteSimpleXMLElement(outfile, 'short_name', self.short_name, inner_indent) if self.help: _WriteSimpleXMLElement(outfile, 'meaning', self.help, inner_indent) # The default flag value can either be represented as a string like on the # command line, or as a Python object. We serialize this value in the # latter case in order to remain consistent. if self.serializer and not isinstance(self.default, str): default_serialized = self.serializer.Serialize(self.default) else: default_serialized = self.default _WriteSimpleXMLElement(outfile, 'default', default_serialized, inner_indent) _WriteSimpleXMLElement(outfile, 'current', self.value, inner_indent) _WriteSimpleXMLElement(outfile, 'type', self.Type(), inner_indent) # Print extra flag features this flag may have. self._WriteCustomInfoInXMLFormat(outfile, inner_indent) outfile.write(indent + '</flag>\n') def _WriteCustomInfoInXMLFormat(self, outfile, indent): """Writes extra info about this flag, in XML format. "Extra" means "not already printed by WriteInfoInXMLFormat above." Args: outfile: File object we write to. indent: A string that is prepended to each generated line. """ # Usually, the parser knows the extra details about the flag, so # we just forward the call to it. self.parser.WriteCustomInfoInXMLFormat(outfile, indent) # End of Flag definition class _ArgumentParserCache(type): """Metaclass used to cache and share argument parsers among flags.""" _instances = {} def __call__(mcs, *args, **kwargs): """Returns an instance of the argument parser cls. This method overrides behavior of the __new__ methods in all subclasses of ArgumentParser (inclusive). If an instance for mcs with the same set of arguments exists, this instance is returned, otherwise a new instance is created. If any keyword arguments are defined, or the values in args are not hashable, this method always returns a new instance of cls. Args: args: Positional initializer arguments. kwargs: Initializer keyword arguments. Returns: An instance of cls, shared or new. """ if kwargs: return type.__call__(mcs, *args, **kwargs) else: instances = mcs._instances key = (mcs,) + tuple(args) try: return instances[key] except KeyError: # No cache entry for key exists, create a new one. return instances.setdefault(key, type.__call__(mcs, *args)) except TypeError: # An object in args cannot be hashed, always return # a new instance. return type.__call__(mcs, *args) class ArgumentParser(object): """Base class used to parse and convert arguments. The Parse() method checks to make sure that the string argument is a legal value and convert it to a native type. If the value cannot be converted, it should throw a 'ValueError' exception with a human readable explanation of why the value is illegal. Subclasses should also define a syntactic_help string which may be presented to the user to describe the form of the legal values. Argument parser classes must be stateless, since instances are cached and shared between flags. Initializer arguments are allowed, but all member variables must be derived from initializer arguments only. """ __metaclass__ = _ArgumentParserCache syntactic_help = "" def Parse(self, argument): """Default implementation: always returns its argument unmodified.""" return argument def Type(self): return 'string' def WriteCustomInfoInXMLFormat(self, outfile, indent): pass class ArgumentSerializer: """Base class for generating string representations of a flag value.""" def Serialize(self, value): return str(value) class ListSerializer(ArgumentSerializer): def __init__(self, list_sep): self.list_sep = list_sep def Serialize(self, value): return self.list_sep.join([str(x) for x in value]) # Flags validators def RegisterValidator(flag_name, checker, message='Flag validation failed', flag_values=FLAGS): """Adds a constraint, which will be enforced during program execution. The constraint is validated when flags are initially parsed, and after each change of the corresponding flag's value. Args: flag_name: string, name of the flag to be checked. checker: method to validate the flag. input - value of the corresponding flag (string, boolean, etc. This value will be passed to checker by the library). See file's docstring for examples. output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise gflags_validators.Error(desired_error_message). message: error text to be shown to the user if checker returns False. If checker raises gflags_validators.Error, message from the raised Error will be shown. flag_values: FlagValues Raises: AttributeError: if flag_name is not registered as a valid flag name. """ flag_values.AddValidator(gflags_validators.SimpleValidator(flag_name, checker, message)) def MarkFlagAsRequired(flag_name, flag_values=FLAGS): """Ensure that flag is not None during program execution. Registers a flag validator, which will follow usual validator rules. Args: flag_name: string, name of the flag flag_values: FlagValues Raises: AttributeError: if flag_name is not registered as a valid flag name. """ RegisterValidator(flag_name, lambda value: value is not None, message='Flag --%s must be specified.' % flag_name, flag_values=flag_values) def _RegisterBoundsValidatorIfNeeded(parser, name, flag_values): """Enforce lower and upper bounds for numeric flags. Args: parser: NumericParser (either FloatParser or IntegerParser). Provides lower and upper bounds, and help text to display. name: string, name of the flag flag_values: FlagValues """ if parser.lower_bound is not None or parser.upper_bound is not None: def Checker(value): if value is not None and parser.IsOutsideBounds(value): message = '%s is not %s' % (value, parser.syntactic_help) raise gflags_validators.Error(message) return True RegisterValidator(name, Checker, flag_values=flag_values) # The DEFINE functions are explained in mode details in the module doc string. def DEFINE(parser, name, default, help, flag_values=FLAGS, serializer=None, **args): """Registers a generic Flag object. NOTE: in the docstrings of all DEFINE* functions, "registers" is short for "creates a new flag and registers it". Auxiliary function: clients should use the specialized DEFINE_<type> function instead. Args: parser: ArgumentParser that is used to parse the flag arguments. name: A string, the flag name. default: The default value of the flag. help: A help string. flag_values: FlagValues object the flag will be registered with. serializer: ArgumentSerializer that serializes the flag value. args: Dictionary with extra keyword args that are passes to the Flag __init__. """ DEFINE_flag(Flag(parser, serializer, name, default, help, **args), flag_values) def DEFINE_flag(flag, flag_values=FLAGS): """Registers a 'Flag' object with a 'FlagValues' object. By default, the global FLAGS 'FlagValue' object is used. Typical users will use one of the more specialized DEFINE_xxx functions, such as DEFINE_string or DEFINE_integer. But developers who need to create Flag objects themselves should use this function to register their flags. """ # copying the reference to flag_values prevents pychecker warnings fv = flag_values fv[flag.name] = flag # Tell flag_values who's defining the flag. if isinstance(flag_values, FlagValues): # Regarding the above isinstance test: some users pass funny # values of flag_values (e.g., {}) in order to avoid the flag # registration (in the past, there used to be a flag_values == # FLAGS test here) and redefine flags with the same name (e.g., # debug). To avoid breaking their code, we perform the # registration only if flag_values is a real FlagValues object. flag_values._RegisterFlagByModule(_GetCallingModule(), flag) def _InternalDeclareKeyFlags(flag_names, flag_values=FLAGS, key_flag_values=None): """Declares a flag as key for the calling module. Internal function. User code should call DECLARE_key_flag or ADOPT_module_key_flags instead. Args: flag_names: A list of strings that are names of already-registered Flag objects. flag_values: A FlagValues object that the flags listed in flag_names have registered with (the value of the flag_values argument from the DEFINE_* calls that defined those flags). This should almost never need to be overridden. key_flag_values: A FlagValues object that (among possibly many other things) keeps track of the key flags for each module. Default None means "same as flag_values". This should almost never need to be overridden. Raises: UnrecognizedFlagError: when we refer to a flag that was not defined yet. """ key_flag_values = key_flag_values or flag_values module = _GetCallingModule() for flag_name in flag_names: if flag_name not in flag_values: raise UnrecognizedFlagError(flag_name) flag = flag_values.FlagDict()[flag_name] key_flag_values._RegisterKeyFlagForModule(module, flag) def DECLARE_key_flag(flag_name, flag_values=FLAGS): """Declares one flag as key to the current module. Key flags are flags that are deemed really important for a module. They are important when listing help messages; e.g., if the --helpshort command-line flag is used, then only the key flags of the main module are listed (instead of all flags, as in the case of --help). Sample usage: flags.DECLARED_key_flag('flag_1') Args: flag_name: A string, the name of an already declared flag. (Redeclaring flags as key, including flags implicitly key because they were declared in this module, is a no-op.) flag_values: A FlagValues object. This should almost never need to be overridden. """ if flag_name in _SPECIAL_FLAGS: # Take care of the special flags, e.g., --flagfile, --undefok. # These flags are defined in _SPECIAL_FLAGS, and are treated # specially during flag parsing, taking precedence over the # user-defined flags. _InternalDeclareKeyFlags([flag_name], flag_values=_SPECIAL_FLAGS, key_flag_values=flag_values) return _InternalDeclareKeyFlags([flag_name], flag_values=flag_values) def ADOPT_module_key_flags(module, flag_values=FLAGS): """Declares that all flags key to a module are key to the current module. Args: module: A module object. flag_values: A FlagValues object. This should almost never need to be overridden. Raises: FlagsError: When given an argument that is a module name (a string), instead of a module object. """ # NOTE(salcianu): an even better test would be if not # isinstance(module, types.ModuleType) but I didn't want to import # types for such a tiny use. if isinstance(module, str): raise FlagsError('Received module name %s; expected a module object.' % module) _InternalDeclareKeyFlags( [f.name for f in flag_values._GetKeyFlagsForModule(module.__name__)], flag_values=flag_values) # If module is this flag module, take _SPECIAL_FLAGS into account. if module == _GetThisModuleObjectAndName()[0]: _InternalDeclareKeyFlags( # As we associate flags with _GetCallingModule(), the special # flags defined in this module are incorrectly registered with # a different module. So, we can't use _GetKeyFlagsForModule. # Instead, we take all flags from _SPECIAL_FLAGS (a private # FlagValues, where no other module should register flags). [f.name for f in _SPECIAL_FLAGS.FlagDict().values()], flag_values=_SPECIAL_FLAGS, key_flag_values=flag_values) # # STRING FLAGS # def DEFINE_string(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value can be any string.""" parser = ArgumentParser() serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) # # BOOLEAN FLAGS # # and the special HELP flags. class BooleanParser(ArgumentParser): """Parser of boolean values.""" def Convert(self, argument): """Converts the argument to a boolean; raise ValueError on errors.""" if type(argument) == str: if argument.lower() in ['true', 't', '1']: return True elif argument.lower() in ['false', 'f', '0']: return False bool_argument = bool(argument) if argument == bool_argument: # The argument is a valid boolean (True, False, 0, or 1), and not just # something that always converts to bool (list, string, int, etc.). return bool_argument raise ValueError('Non-boolean argument to boolean flag', argument) def Parse(self, argument): val = self.Convert(argument) return val def Type(self): return 'bool' class BooleanFlag(Flag): """Basic boolean flag. Boolean flags do not take any arguments, and their value is either True (1) or False (0). The false value is specified on the command line by prepending the word 'no' to either the long or the short flag name. For example, if a Boolean flag was created whose long name was 'update' and whose short name was 'x', then this flag could be explicitly unset through either --noupdate or --nox. """ def __init__(self, name, default, help, short_name=None, **args): p = BooleanParser() Flag.__init__(self, p, None, name, default, help, short_name, 1, **args) if not self.help: self.help = "a boolean value" def DEFINE_boolean(name, default, help, flag_values=FLAGS, **args): """Registers a boolean flag. Such a boolean flag does not take an argument. If a user wants to specify a false value explicitly, the long option beginning with 'no' must be used: i.e. --noflag This flag will have a value of None, True or False. None is possible if default=None and the user does not specify the flag on the command line. """ DEFINE_flag(BooleanFlag(name, default, help, **args), flag_values) # Match C++ API to unconfuse C++ people. DEFINE_bool = DEFINE_boolean class HelpFlag(BooleanFlag): """ HelpFlag is a special boolean flag that prints usage information and raises a SystemExit exception if it is ever found in the command line arguments. Note this is called with allow_override=1, so other apps can define their own --help flag, replacing this one, if they want. """ def __init__(self): BooleanFlag.__init__(self, "help", 0, "show this help", short_name="?", allow_override=1) def Parse(self, arg): if arg: doc = sys.modules["__main__"].__doc__ flags = str(FLAGS) print doc or ("\nUSAGE: %s [flags]\n" % sys.argv[0]) if flags: print "flags:" print flags sys.exit(1) class HelpXMLFlag(BooleanFlag): """Similar to HelpFlag, but generates output in XML format.""" def __init__(self): BooleanFlag.__init__(self, 'helpxml', False, 'like --help, but generates XML output', allow_override=1) def Parse(self, arg): if arg: FLAGS.WriteHelpInXMLFormat(sys.stdout) sys.exit(1) class HelpshortFlag(BooleanFlag): """ HelpshortFlag is a special boolean flag that prints usage information for the "main" module, and rasies a SystemExit exception if it is ever found in the command line arguments. Note this is called with allow_override=1, so other apps can define their own --helpshort flag, replacing this one, if they want. """ def __init__(self): BooleanFlag.__init__(self, "helpshort", 0, "show usage only for this module", allow_override=1) def Parse(self, arg): if arg: doc = sys.modules["__main__"].__doc__ flags = FLAGS.MainModuleHelp() print doc or ("\nUSAGE: %s [flags]\n" % sys.argv[0]) if flags: print "flags:" print flags sys.exit(1) # # Numeric parser - base class for Integer and Float parsers # class NumericParser(ArgumentParser): """Parser of numeric values. Parsed value may be bounded to a given upper and lower bound. """ def IsOutsideBounds(self, val): return ((self.lower_bound is not None and val < self.lower_bound) or (self.upper_bound is not None and val > self.upper_bound)) def Parse(self, argument): val = self.Convert(argument) if self.IsOutsideBounds(val): raise ValueError("%s is not %s" % (val, self.syntactic_help)) return val def WriteCustomInfoInXMLFormat(self, outfile, indent): if self.lower_bound is not None: _WriteSimpleXMLElement(outfile, 'lower_bound', self.lower_bound, indent) if self.upper_bound is not None: _WriteSimpleXMLElement(outfile, 'upper_bound', self.upper_bound, indent) def Convert(self, argument): """Default implementation: always returns its argument unmodified.""" return argument # End of Numeric Parser # # FLOAT FLAGS # class FloatParser(NumericParser): """Parser of floating point values. Parsed value may be bounded to a given upper and lower bound. """ number_article = "a" number_name = "number" syntactic_help = " ".join((number_article, number_name)) def __init__(self, lower_bound=None, upper_bound=None): super(FloatParser, self).__init__() self.lower_bound = lower_bound self.upper_bound = upper_bound sh = self.syntactic_help if lower_bound is not None and upper_bound is not None: sh = ("%s in the range [%s, %s]" % (sh, lower_bound, upper_bound)) elif lower_bound == 0: sh = "a non-negative %s" % self.number_name elif upper_bound == 0: sh = "a non-positive %s" % self.number_name elif upper_bound is not None: sh = "%s <= %s" % (self.number_name, upper_bound) elif lower_bound is not None: sh = "%s >= %s" % (self.number_name, lower_bound) self.syntactic_help = sh def Convert(self, argument): """Converts argument to a float; raises ValueError on errors.""" return float(argument) def Type(self): return 'float' # End of FloatParser def DEFINE_float(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value must be a float. If lower_bound or upper_bound are set, then this flag must be within the given range. """ parser = FloatParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) _RegisterBoundsValidatorIfNeeded(parser, name, flag_values=flag_values) # # INTEGER FLAGS # class IntegerParser(NumericParser): """Parser of an integer value. Parsed value may be bounded to a given upper and lower bound. """ number_article = "an" number_name = "integer" syntactic_help = " ".join((number_article, number_name)) def __init__(self, lower_bound=None, upper_bound=None): super(IntegerParser, self).__init__() self.lower_bound = lower_bound self.upper_bound = upper_bound sh = self.syntactic_help if lower_bound is not None and upper_bound is not None: sh = ("%s in the range [%s, %s]" % (sh, lower_bound, upper_bound)) elif lower_bound == 1: sh = "a positive %s" % self.number_name elif upper_bound == -1: sh = "a negative %s" % self.number_name elif lower_bound == 0: sh = "a non-negative %s" % self.number_name elif upper_bound == 0: sh = "a non-positive %s" % self.number_name elif upper_bound is not None: sh = "%s <= %s" % (self.number_name, upper_bound) elif lower_bound is not None: sh = "%s >= %s" % (self.number_name, lower_bound) self.syntactic_help = sh def Convert(self, argument): __pychecker__ = 'no-returnvalues' if type(argument) == str: base = 10 if len(argument) > 2 and argument[0] == "0" and argument[1] == "x": base = 16 try: return int(argument, base) # ValueError is thrown when argument is a string, and overflows an int. except ValueError: return long(argument, base) else: try: return int(argument) # OverflowError is thrown when argument is numeric, and overflows an int. except OverflowError: return long(argument) def Type(self): return 'int' def DEFINE_integer(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value must be an integer. If lower_bound, or upper_bound are set, then this flag must be within the given range. """ parser = IntegerParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) _RegisterBoundsValidatorIfNeeded(parser, name, flag_values=flag_values) # # ENUM FLAGS # class EnumParser(ArgumentParser): """Parser of a string enum value (a string value from a given set). If enum_values (see below) is not specified, any string is allowed. """ def __init__(self, enum_values=None): super(EnumParser, self).__init__() self.enum_values = enum_values def Parse(self, argument): if self.enum_values and argument not in self.enum_values: raise ValueError("value should be one of <%s>" % "|".join(self.enum_values)) return argument def Type(self): return 'string enum' class EnumFlag(Flag): """Basic enum flag; its value can be any string from list of enum_values.""" def __init__(self, name, default, help, enum_values=None, short_name=None, **args): enum_values = enum_values or [] p = EnumParser(enum_values) g = ArgumentSerializer() Flag.__init__(self, p, g, name, default, help, short_name, **args) if not self.help: self.help = "an enum string" self.help = "<%s>: %s" % ("|".join(enum_values), self.help) def _WriteCustomInfoInXMLFormat(self, outfile, indent): for enum_value in self.parser.enum_values: _WriteSimpleXMLElement(outfile, 'enum_value', enum_value, indent) def DEFINE_enum(name, default, enum_values, help, flag_values=FLAGS, **args): """Registers a flag whose value can be any string from enum_values.""" DEFINE_flag(EnumFlag(name, default, help, enum_values, ** args), flag_values) # # LIST FLAGS # class BaseListParser(ArgumentParser): """Base class for a parser of lists of strings. To extend, inherit from this class; from the subclass __init__, call BaseListParser.__init__(self, token, name) where token is a character used to tokenize, and name is a description of the separator. """ def __init__(self, token=None, name=None): assert name super(BaseListParser, self).__init__() self._token = token self._name = name self.syntactic_help = "a %s separated list" % self._name def Parse(self, argument): if isinstance(argument, list): return argument elif argument == '': return [] else: return [s.strip() for s in argument.split(self._token)] def Type(self): return '%s separated list of strings' % self._name class ListParser(BaseListParser): """Parser for a comma-separated list of strings.""" def __init__(self): BaseListParser.__init__(self, ',', 'comma') def WriteCustomInfoInXMLFormat(self, outfile, indent): BaseListParser.WriteCustomInfoInXMLFormat(self, outfile, indent) _WriteSimpleXMLElement(outfile, 'list_separator', repr(','), indent) class WhitespaceSeparatedListParser(BaseListParser): """Parser for a whitespace-separated list of strings.""" def __init__(self): BaseListParser.__init__(self, None, 'whitespace') def WriteCustomInfoInXMLFormat(self, outfile, indent): BaseListParser.WriteCustomInfoInXMLFormat(self, outfile, indent) separators = list(string.whitespace) separators.sort() for ws_char in string.whitespace: _WriteSimpleXMLElement(outfile, 'list_separator', repr(ws_char), indent) def DEFINE_list(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value is a comma-separated list of strings.""" parser = ListParser() serializer = ListSerializer(',') DEFINE(parser, name, default, help, flag_values, serializer, **args) def DEFINE_spaceseplist(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value is a whitespace-separated list of strings. Any whitespace can be used as a separator. """ parser = WhitespaceSeparatedListParser() serializer = ListSerializer(' ') DEFINE(parser, name, default, help, flag_values, serializer, **args) # # MULTI FLAGS # class MultiFlag(Flag): """A flag that can appear multiple time on the command-line. The value of such a flag is a list that contains the individual values from all the appearances of that flag on the command-line. See the __doc__ for Flag for most behavior of this class. Only differences in behavior are described here: * The default value may be either a single value or a list of values. A single value is interpreted as the [value] singleton list. * The value of the flag is always a list, even if the option was only supplied once, and even if the default value is a single value """ def __init__(self, *args, **kwargs): Flag.__init__(self, *args, **kwargs) self.help += ';\n repeat this option to specify a list of values' def Parse(self, arguments): """Parses one or more arguments with the installed parser. Args: arguments: a single argument or a list of arguments (typically a list of default values); a single argument is converted internally into a list containing one item. """ if not isinstance(arguments, list): # Default value may be a list of values. Most other arguments # will not be, so convert them into a single-item list to make # processing simpler below. arguments = [arguments] if self.present: # keep a backup reference to list of previously supplied option values values = self.value else: # "erase" the defaults with an empty list values = [] for item in arguments: # have Flag superclass parse argument, overwriting self.value reference Flag.Parse(self, item) # also increments self.present values.append(self.value) # put list of option values back in the 'value' attribute self.value = values def Serialize(self): if not self.serializer: raise FlagsError("Serializer not present for flag %s" % self.name) if self.value is None: return '' s = '' multi_value = self.value for self.value in multi_value: if s: s += ' ' s += Flag.Serialize(self) self.value = multi_value return s def Type(self): return 'multi ' + self.parser.Type() def DEFINE_multi(parser, serializer, name, default, help, flag_values=FLAGS, **args): """Registers a generic MultiFlag that parses its args with a given parser. Auxiliary function. Normal users should NOT use it directly. Developers who need to create their own 'Parser' classes for options which can appear multiple times can call this module function to register their flags. """ DEFINE_flag(MultiFlag(parser, serializer, name, default, help, **args), flag_values) def DEFINE_multistring(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value can be a list of any strings. Use the flag on the command line multiple times to place multiple string values into the list. The 'default' may be a single string (which will be converted into a single-element list) or a list of strings. """ parser = ArgumentParser() serializer = ArgumentSerializer() DEFINE_multi(parser, serializer, name, default, help, flag_values, **args) def DEFINE_multi_int(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value can be a list of arbitrary integers. Use the flag on the command line multiple times to place multiple integer values into the list. The 'default' may be a single integer (which will be converted into a single-element list) or a list of integers. """ parser = IntegerParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE_multi(parser, serializer, name, default, help, flag_values, **args) # Now register the flags that we want to exist in all applications. # These are all defined with allow_override=1, so user-apps can use # these flagnames for their own purposes, if they want. DEFINE_flag(HelpFlag()) DEFINE_flag(HelpshortFlag()) DEFINE_flag(HelpXMLFlag()) # Define special flags here so that help may be generated for them. # NOTE: Please do NOT use _SPECIAL_FLAGS from outside this module. _SPECIAL_FLAGS = FlagValues() DEFINE_string( 'flagfile', "", "Insert flag definitions from the given file into the command line.", _SPECIAL_FLAGS) DEFINE_string( 'undefok', "", "comma-separated list of flag names that it is okay to specify " "on the command line even if the program does not define a flag " "with that name. IMPORTANT: flags in this list that have " "arguments MUST use the --flag=value format.", _SPECIAL_FLAGS)
Python
#!/usr/bin/python2.4 # # Copyright 2010 Google Inc. All Rights Reserved. """Discovery document tests Functional tests that verify we can retrieve data from existing services. """ __author__ = 'ade@google.com (Ade Oshineye)' import httplib2 import pprint from apiclient.discovery import build import httplib2 import logging import pickle import os import time import unittest # TODO(ade) Remove this mock once the bug in the discovery document is fixed DATA_DIR = os.path.join(logging.os.path.dirname(__file__), '../tests/data') class HttpMock(object): def __init__(self, filename, headers): f = file(os.path.join(DATA_DIR, filename), 'r') self.data = f.read() f.close() self.headers = headers def request(self, uri, method="GET", body=None, headers=None, redirections=1, connection_type=None): return httplib2.Response(self.headers), self.data class BuzzFunctionalTest(unittest.TestCase): def test_can_get_specific_activity(self): buzz = build('buzz', 'v1') activity = buzz.activities().get(userId='105037104815911535953', postId='B:z12sspviqyakfvye123wehng0muwz5jzq04').execute() self.assertTrue(activity is not None) def test_can_get_specific_activity_with_tag_id(self): buzz = build('buzz', 'v1') activity = buzz.activities().get(userId='105037104815911535953', postId='tag:google.com,2010:buzz:z13ptnw5usmnv15ey22fzlswnuqoebasu').execute() self.assertTrue(activity is not None) def test_can_get_buzz_activities_with_many_params(self): buzz = build('buzz', 'v1') max_results = 2 activities_command = buzz.activities() activities = activities_command.list(userId='googlebuzz', scope='@self', max_comments=max_results*2 ,max_liked=max_results*3, max_results=max_results).execute() activity_count = len(activities['items']) self.assertEquals(max_results, activity_count) activities = activities_command.list_next(activities).execute() activity_count = len(activities['items']) self.assertEquals(max_results, activity_count) def test_can_get_multiple_pages_of_buzz_activities(self): buzz = build('buzz', 'v1') max_results = 2 activities_command = buzz.activities() activities = activities_command.list(userId='adewale', scope='@self', max_results=max_results).execute() for count in range(10): activities = activities_command.list_next(activities).execute() activity_count = len(activities['items']) self.assertEquals(max_results, activity_count, 'Failed after %s pages' % str(count)) def IGNORE__test_can_get_multiple_pages_of_buzz_likers(self): # Ignore this test until the Buzz API fixes the bug with next links # http://code.google.com/p/google-buzz-api/issues/detail?id=114 self.http = HttpMock('buzz.json', {'status': '200'}) buzz = build('buzz', 'v1', self.http) max_results = 1 people_cmd = buzz.people() # The post https://www.googleapis.com/buzz/v1/activities/111062888259659218284/@self/B:z13nh535yk2syfob004cdjyb3mjeulcwv3c?alt=json# #Perform this call https://www.googleapis.com/buzz/v1/activities/111062888259659218284/@self/B:z13nh535yk2syfob004cdjyb3mjeulcwv3c/@liked?alt=json&max-results=1 people = people_cmd.liked(groupId='@liked', userId='googlebuzz', scope='@self', postId='B:z13nh535yk2syfob004cdjyb3mjeulcwv3c', max_results=max_results).execute() for count in range(10): people = people_cmd.liked_next(people).execute() people_count = len(people['items']) self.assertEquals(max_results, people_count, 'Failed after %s pages' % str(count)) def test_can_get_user_profile(self): buzz = build('buzz', 'v1') person = buzz.people().get(userId='googlebuzz').execute() self.assertTrue(person is not None) self.assertEquals('buzz#person', person['kind']) self.assertEquals('Google Buzz Team', person['displayName']) self.assertEquals('111062888259659218284', person['id']) self.assertEquals('https://profiles.google.com/googlebuzz', person['profileUrl']) def test_can_get_user_profile_using_numeric_identifier(self): buzz = build('buzz', 'v1') person = buzz.people().get(userId='108242092577082601423').execute() self.assertTrue(person is not None) self.assertEquals('buzz#person', person['kind']) self.assertEquals('Test Account', person['displayName']) self.assertEquals('108242092577082601423', person['id']) self.assertEquals('https://profiles.google.com/108242092577082601423', person['profileUrl']) def test_can_get_followees_of_user(self): buzz = build('buzz', 'v1') expected_followees = 30 following = buzz.people().list(userId='googlebuzz', groupId='@following', max_results=expected_followees).execute() self.assertEquals(expected_followees, following['totalResults']) self.assertEquals(expected_followees, len(following['entry'])) def test_can_efficiently_get_follower_count_of_user(self): buzz = build('buzz', 'v1') # Restricting max_results to 1 means only a tiny amount of data comes back but the totalResults still has the total. followers = buzz.people().list(userId='googlebuzz', groupId='@followers', max_results='1').execute() # @googlebuzz has a large but fluctuating number of followers # It is sufficient if the result is bigger than 10, 000 follower_count = followers['totalResults'] self.assertTrue(follower_count > 10000, follower_count) def test_follower_count_is_missing_for_user_with_hidden_follower_count(self): buzz = build('buzz', 'v1') followers = buzz.people().list(userId='adewale', groupId='@followers').execute() self.assertFalse('totalResults' in followers) class BuzzAuthenticatedFunctionalTest(unittest.TestCase): def __init__(self, method_name): unittest.TestCase.__init__(self, method_name) credentials_dir = os.path.join(logging.os.path.dirname(__file__), './data') f = file(os.path.join(credentials_dir, 'buzz_credentials.dat'), 'r') credentials = pickle.loads(f.read()) f.close() self.http = credentials.authorize(httplib2.Http()) def test_can_create_activity(self): buzz = build('buzz', 'v1', http=self.http) activity = buzz.activities().insert(userId='@me', body={ 'data': { 'title': 'Testing insert', 'object': { 'content': u'Just a short note to show that insert is working. ?', 'type': 'note'} } } ).execute() self.assertTrue(activity is not None) def test_can_create_private_activity(self): buzz = build('buzz', 'v1', http=self.http) activity = buzz.activities().insert(userId='@me', body={ 'data': { 'title': 'Testing insert', 'object': { 'content': 'This is a private post.' }, 'visibility': { 'entries': [ { 'id': 'tag:google.com,2010:buzz-group:108242092577082601423:13' } ] } } } ).execute() self.assertTrue(activity is not None) def test_can_create_and_delete_new_group(self): buzz = build('buzz', 'v1', http=self.http) group_name = 'New Group Created At' + str(time.time()) group = buzz.groups().insert(userId='@me', body = { 'data': { 'title': group_name } }).execute() self.assertTrue(group is not None) result = buzz.groups().delete(userId='@me', groupId=group['id']).execute() self.assertEquals({}, result) def test_can_identify_number_of_groups_belonging_to_user(self): buzz = build('buzz', 'v1', http=self.http) groups = buzz.groups().list(userId='108242092577082601423').execute() # This should work as long as no-one deletes the 4 default groups for this test account expected_default_number_of_groups = 4 self.assertTrue(len(groups['items']) > expected_default_number_of_groups) def IGNORE__test_can_like_activity(self): buzz = build('buzz', 'v1', http=self.http) activity = buzz.activities().insert(userId='@me', body={ 'data': { 'title': 'Testing insert', 'object': { 'content': u'Just a short note to show that insert is working. ?', 'type': 'note'} } } ).execute() pprint.pprint(activity) id = activity['id'] likers = buzz.people().liked(userId='105037104815911535953', postId=id, groupId='@liked', scope='@self').execute() # Todo(ade) Insert the new liker once the Buzz back-end bug is fixed def test_can_comment_on_activity(self): buzz = build('buzz', 'v1', http=self.http) activity = buzz.activities().insert(userId='@me', body={ 'data': { 'title': 'A new activity', 'object': { 'content': u'The body of the new activity', 'type': 'note'} } } ).execute() id = activity['id'] comment = buzz.comments().insert(userId='@me', postId=id, body={ 'data': { 'content': 'A comment on the new activity' } }).execute() def test_can_list_groups_belonging_to_user(self): buzz = build('buzz', 'v1', http=self.http) groups = buzz.groups().list(userId='108242092577082601423').execute() group = buzz.groups().get(userId='108242092577082601423', groupId='G:108242092577082601423:15').execute() self.assertEquals('G:108242092577082601423:15', group['id'], group) group = buzz.groups().get(userId='108242092577082601423', groupId='G:108242092577082601423:14').execute() self.assertEquals('G:108242092577082601423:14', group['id'], group) group = buzz.groups().get(userId='108242092577082601423', groupId='G:108242092577082601423:13').execute() self.assertEquals('G:108242092577082601423:13', group['id'], group) group = buzz.groups().get(userId='108242092577082601423', groupId='G:108242092577082601423:6').execute() self.assertEquals('G:108242092577082601423:6', group['id'], group) def test_can_delete_activity(self): buzz = build('buzz', 'v1', http=self.http) activity = buzz.activities().insert(userId='@me', body={ 'data': { 'title': 'Activity to be deleted', 'object': { 'content': u'Created this activity so that it can be deleted.', 'type': 'note'} } } ).execute() id = activity['id'] buzz.activities().delete(scope='@self', userId='@me', postId=id).execute() time.sleep(2) activity_url = activity['links']['self'][0]['href'] resp, content = self.http.request(activity_url, 'GET') self.assertEquals(404, resp.status) if __name__ == '__main__': unittest.main()
Python
# Copyright (C) 2010 Google Inc. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. """Sample for threading and queues. A simple sample that processes many requests by constructing a threadpool and passing client requests by a thread queue to be processed. """ from apiclient.discovery import build from apiclient.errors import HttpError from oauth2client.file import Storage from oauth2client.client import OAuth2WebServerFlow from oauth2client.tools import run import Queue import gflags import httplib2 import logging import sys import threading import time # How many threads to start. NUM_THREADS = 3 # A list of URLs to shorten. BULK = [ "https://code.google.com/apis/buzz/", "https://code.google.com/apis/moderator/", "https://code.google.com/apis/latitude/", "https://code.google.com/apis/urlshortener/", "https://code.google.com/apis/customsearch/", "https://code.google.com/apis/shopping/search/", "https://code.google.com/apis/predict", "https://code.google.com/more", ] FLAGS = gflags.FLAGS FLOW = OAuth2WebServerFlow( client_id='433807057907.apps.googleusercontent.com', client_secret='jigtZpMApkRxncxikFpR+SFg', scope='https://www.googleapis.com/auth/urlshortener', user_agent='urlshortener-cmdline-sample/1.0') gflags.DEFINE_enum('logging_level', 'ERROR', ['DEBUG', 'INFO', 'WARNING', 'ERROR', 'CRITICAL'], 'Set the level of logging detail.') queue = Queue.Queue() class Backoff: """Exponential Backoff Implements an exponential backoff algorithm. Instantiate and call loop() each time through the loop, and each time a request fails call fail() which will delay an appropriate amount of time. """ def __init__(self, maxretries=8): self.retry = 0 self.maxretries = maxretries self.first = True def loop(self): if self.first: self.first = False return True else: return self.retry < self.maxretries def fail(self): self.retry += 1 delay = 2 ** self.retry time.sleep(delay) def start_threads(credentials): """Create the thread pool to process the requests.""" def process_requests(n): http = httplib2.Http() http = credentials.authorize(http) loop = True while loop: request = queue.get() backoff = Backoff() while backoff.loop(): try: response = request.execute(http) print "Processed: %s in thread %d" % (response['id'], n) break except HttpError, e: if e.resp.status in [402, 403, 408, 503, 504]: print "Increasing backoff, got status code: %d" % e.resp.status backoff.fail() except Exception, e: print "Unexpected error. Exiting." + str(e) loop = False break print "Completed request" queue.task_done() for i in range(NUM_THREADS): t = threading.Thread(target=process_requests, args=[i]) t.daemon = True t.start() def main(argv): try: argv = FLAGS(argv) except gflags.FlagsError, e: print '%s\\nUsage: %s ARGS\\n%s' % (e, argv[0], FLAGS) sys.exit(1) logging.getLogger().setLevel(getattr(logging, FLAGS.logging_level)) storage = Storage('threadqueue.dat') credentials = storage.get() if credentials is None or credentials.invalid == True: credentials = run(FLOW, storage) start_threads(credentials) http = httplib2.Http() http = credentials.authorize(http) service = build("urlshortener", "v1", http=http, developerKey="AIzaSyDRRpR3GS1F1_jKNNM9HCNd2wJQyPG3oN0") shortener = service.url() for url in BULK: body = {"longUrl": url } shorten_request = shortener.insert(body=body) print "Adding request to queue" queue.put(shorten_request) # Wait for all the requests to finish queue.join() if __name__ == "__main__": main(sys.argv)
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Simple command-line example for Buzz. Command-line application that retrieves the users latest content and then adds a new entry. """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' from apiclient.discovery import build from apiclient.discovery import build_from_document from apiclient.oauth import FlowThreeLegged from apiclient.ext.authtools import run from apiclient.ext.file import Storage from apiclient.oauth import CredentialsInvalidError import gflags import sys import httplib2 import logging import os import pprint import sys FLAGS = gflags.FLAGS gflags.DEFINE_enum('logging_level', 'ERROR', ['DEBUG', 'INFO', 'WARNING', 'ERROR', 'CRITICAL'], 'Set the level of logging detail.') def main(argv): try: argv = FLAGS(argv) except gflags.FlagsError, e: print '%s\\nUsage: %s ARGS\\n%s' % (e, argv[0], FLAGS) sys.exit(1) logging.getLogger().setLevel(getattr(logging, FLAGS.logging_level)) storage = Storage('buzz.dat') credentials = storage.get() if credentials is None or credentials.invalid == True: buzz_discovery = build("buzz", "v1").auth_discovery() flow = FlowThreeLegged(buzz_discovery, consumer_key='anonymous', consumer_secret='anonymous', user_agent='python-buzz-sample/1.0', domain='anonymous', scope='https://www.googleapis.com/auth/buzz', xoauth_displayname='Google API Client Example App') credentials = run(flow, storage) http = httplib2.Http() http = credentials.authorize(http) # Load the local copy of the discovery document f = file(os.path.join(os.path.dirname(__file__), "buzz.json"), "r") discovery = f.read() f.close() # Optionally load a futures discovery document f = file(os.path.join(os.path.dirname(__file__), "../../apiclient/contrib/buzz/future.json"), "r") future = f.read() f.close() # Construct a service from the local documents service = build_from_document(discovery, base="https://www.googleapis.com/", future=future, http=http, developerKey="AIzaSyDRRpR3GS1F1_jKNNM9HCNd2wJQyPG3oN0") activities = service.activities() try: # Retrieve the first two activities activitylist = activities.list( max_results='2', scope='@self', userId='@me').execute() print "Retrieved the first two activities" except CredentialsInvalidError: print 'Your credentials are no longer valid.' print 'Please re-run this application to re-authorize.' if __name__ == '__main__': main(sys.argv)
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Simple command-line example for Buzz. Command-line application that retrieves the users latest content and then adds a new entry. """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' from apiclient.discovery import build from apiclient.discovery import build_from_document from apiclient.oauth import FlowThreeLegged from apiclient.ext.authtools import run from apiclient.ext.file import Storage from apiclient.oauth import CredentialsInvalidError import gflags import sys import httplib2 import logging import os import pprint import sys FLAGS = gflags.FLAGS gflags.DEFINE_enum('logging_level', 'ERROR', ['DEBUG', 'INFO', 'WARNING', 'ERROR', 'CRITICAL'], 'Set the level of logging detail.') def main(argv): try: argv = FLAGS(argv) except gflags.FlagsError, e: print '%s\\nUsage: %s ARGS\\n%s' % (e, argv[0], FLAGS) sys.exit(1) logging.getLogger().setLevel(getattr(logging, FLAGS.logging_level)) storage = Storage('buzz.dat') credentials = storage.get() if credentials is None or credentials.invalid == True: buzz_discovery = build("buzz", "v1").auth_discovery() flow = FlowThreeLegged(buzz_discovery, consumer_key='anonymous', consumer_secret='anonymous', user_agent='python-buzz-sample/1.0', domain='anonymous', scope='https://www.googleapis.com/auth/buzz', xoauth_displayname='Google API Client Example App') credentials = run(flow, storage) http = httplib2.Http() http = credentials.authorize(http) # Load the local copy of the discovery document f = file(os.path.join(os.path.dirname(__file__), "buzz.json"), "r") discovery = f.read() f.close() # Optionally load a futures discovery document f = file(os.path.join(os.path.dirname(__file__), "../../apiclient/contrib/buzz/future.json"), "r") future = f.read() f.close() # Construct a service from the local documents service = build_from_document(discovery, base="https://www.googleapis.com/", future=future, http=http, developerKey="AIzaSyDRRpR3GS1F1_jKNNM9HCNd2wJQyPG3oN0") activities = service.activities() try: # Retrieve the first two activities activitylist = activities.list( max_results='2', scope='@self', userId='@me').execute() print "Retrieved the first two activities" except CredentialsInvalidError: print 'Your credentials are no longer valid.' print 'Please re-run this application to re-authorize.' if __name__ == '__main__': main(sys.argv)
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Simple command-line example for Moderator. Command-line application that exercises the Google Moderator API. Usage: $ python moderator.py You can also get help on all the command-line flags the program understands by running: $ python moderator.py --help To get detailed log output run: $ python moderator.py --logging_level=DEBUG """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' import gflags import httplib2 import logging import sys from apiclient.discovery import build from oauth2client.file import Storage from oauth2client.client import OAuth2WebServerFlow from oauth2client.tools import run FLAGS = gflags.FLAGS # Set up a Flow object to be used if we need to authenticate. This # sample uses OAuth 2.0, and we set up the OAuth2WebServerFlow with # the information it needs to authenticate. Note that it is called # the Web Server Flow, but it can also handle the flow for native # applications <http://code.google.com/apis/accounts/docs/OAuth2.html#IA> # The client_id client_secret are copied from the Identity tab on # the Google APIs Console <http://code.google.com/apis/console> FLOW = OAuth2WebServerFlow( client_id='433807057907.apps.googleusercontent.com', client_secret='jigtZpMApkRxncxikFpR+SFg', scope='https://www.googleapis.com/auth/moderator', user_agent='moderator-cmdline-sample/1.0') # The gflags module makes defining command-line options easy for # applications. Run this program with the '--help' argument to see # all the flags that it understands. gflags.DEFINE_enum('logging_level', 'ERROR', ['DEBUG', 'INFO', 'WARNING', 'ERROR', 'CRITICAL'], 'Set the level of logging detail.') def main(argv): # Let the gflags module process the command-line arguments try: argv = FLAGS(argv) except gflags.FlagsError, e: print '%s\\nUsage: %s ARGS\\n%s' % (e, argv[0], FLAGS) sys.exit(1) # Set the logging according to the command-line flag logging.getLogger().setLevel(getattr(logging, FLAGS.logging_level)) # A Storage object is used to storage and retrieve Credentials. # See <http://code.google.com/p/google-api-python-client/wiki/HowAuthenticationWorks> storage = Storage('moderator.dat') credentials = storage.get() # If the Credentials don't exist or are invalid run through the # native client flow. The Storage object will ensure that if successful # the good Credentials will get written back to a file. if credentials is None or credentials.invalid == True: credentials = run(FLOW, storage) # Create an httplib2.Http object to handle our HTTP requests and authorize it # with our good Credentials. http = httplib2.Http(cache=".cache") http = credentials.authorize(http) # Build a service object for interacting with the API. service = build("moderator", "v1", http=http) # Create a new Moderator series. series_body = { "description": "Share and rank tips for eating healthy and cheap!", "name": "Eating Healthy & Cheap", "videoSubmissionAllowed": False } series = service.series().insert(body=series_body).execute() print "Created a new series" # Create a new Moderator topic in that series. topic_body = { "description": "Share your ideas on eating healthy!", "name": "Ideas", "presenter": "liz" } topic = service.topics().insert(seriesId=series['id']['seriesId'], body=topic_body).execute() print "Created a new topic" # Create a new Submission in that topic. submission_body = { "attachmentUrl": "http://www.youtube.com/watch?v=1a1wyc5Xxpg", "attribution": { "displayName": "Bashan", "location": "Bainbridge Island, WA" }, "text": "Charlie Ayers @ Google" } submission = service.submissions().insert(seriesId=topic['id']['seriesId'], topicId=topic['id']['topicId'], body=submission_body).execute() print "Inserted a new submisson on the topic" # Vote on that newly added Submission. vote_body = { "vote": "PLUS" } service.votes().insert(seriesId=topic['id']['seriesId'], submissionId=submission['id']['submissionId'], body=vote_body) print "Voted on the submission" if __name__ == '__main__': main(sys.argv)
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Simple command-line example for Moderator. Command-line application that exercises the Google Moderator API. Usage: $ python moderator.py You can also get help on all the command-line flags the program understands by running: $ python moderator.py --help To get detailed log output run: $ python moderator.py --logging_level=DEBUG """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' import gflags import httplib2 import logging import sys from apiclient.discovery import build from oauth2client.file import Storage from oauth2client.client import OAuth2WebServerFlow from oauth2client.tools import run FLAGS = gflags.FLAGS # Set up a Flow object to be used if we need to authenticate. This # sample uses OAuth 2.0, and we set up the OAuth2WebServerFlow with # the information it needs to authenticate. Note that it is called # the Web Server Flow, but it can also handle the flow for native # applications <http://code.google.com/apis/accounts/docs/OAuth2.html#IA> # The client_id client_secret are copied from the Identity tab on # the Google APIs Console <http://code.google.com/apis/console> FLOW = OAuth2WebServerFlow( client_id='433807057907.apps.googleusercontent.com', client_secret='jigtZpMApkRxncxikFpR+SFg', scope='https://www.googleapis.com/auth/moderator', user_agent='moderator-cmdline-sample/1.0') # The gflags module makes defining command-line options easy for # applications. Run this program with the '--help' argument to see # all the flags that it understands. gflags.DEFINE_enum('logging_level', 'ERROR', ['DEBUG', 'INFO', 'WARNING', 'ERROR', 'CRITICAL'], 'Set the level of logging detail.') def main(argv): # Let the gflags module process the command-line arguments try: argv = FLAGS(argv) except gflags.FlagsError, e: print '%s\\nUsage: %s ARGS\\n%s' % (e, argv[0], FLAGS) sys.exit(1) # Set the logging according to the command-line flag logging.getLogger().setLevel(getattr(logging, FLAGS.logging_level)) # A Storage object is used to storage and retrieve Credentials. # See <http://code.google.com/p/google-api-python-client/wiki/HowAuthenticationWorks> storage = Storage('moderator.dat') credentials = storage.get() # If the Credentials don't exist or are invalid run through the # native client flow. The Storage object will ensure that if successful # the good Credentials will get written back to a file. if credentials is None or credentials.invalid == True: credentials = run(FLOW, storage) # Create an httplib2.Http object to handle our HTTP requests and authorize it # with our good Credentials. http = httplib2.Http(cache=".cache") http = credentials.authorize(http) # Build a service object for interacting with the API. service = build("moderator", "v1", http=http) # Create a new Moderator series. series_body = { "description": "Share and rank tips for eating healthy and cheap!", "name": "Eating Healthy & Cheap", "videoSubmissionAllowed": False } series = service.series().insert(body=series_body).execute() print "Created a new series" # Create a new Moderator topic in that series. topic_body = { "description": "Share your ideas on eating healthy!", "name": "Ideas", "presenter": "liz" } topic = service.topics().insert(seriesId=series['id']['seriesId'], body=topic_body).execute() print "Created a new topic" # Create a new Submission in that topic. submission_body = { "attachmentUrl": "http://www.youtube.com/watch?v=1a1wyc5Xxpg", "attribution": { "displayName": "Bashan", "location": "Bainbridge Island, WA" }, "text": "Charlie Ayers @ Google" } submission = service.submissions().insert(seriesId=topic['id']['seriesId'], topicId=topic['id']['topicId'], body=submission_body).execute() print "Inserted a new submisson on the topic" # Vote on that newly added Submission. vote_body = { "vote": "PLUS" } service.votes().insert(seriesId=topic['id']['seriesId'], submissionId=submission['id']['submissionId'], body=vote_body) print "Voted on the submission" if __name__ == '__main__': main(sys.argv)
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Simple command-line example for running against a local server. """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' # Enable this sample to be run from the top-level directory import os import sys sys.path.insert(0, os.getcwd()) from apiclient.discovery import build import httplib2 # httplib2.debuglevel = 4 import pickle import pprint DISCOVERY_URI = ('http://localhost:3990/discovery/v0.2beta1/describe/' '{api}/{apiVersion}') def main(): http = httplib2.Http() service = build("buzz", "v1", http=http, discoveryServiceUrl=DISCOVERY_URI) help(service.activities().list) print service.activities().list(userId='@self', scope='@me', c='foo').uri if __name__ == '__main__': main()
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Simple command-line example for running against a local server. """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' # Enable this sample to be run from the top-level directory import os import sys sys.path.insert(0, os.getcwd()) from apiclient.discovery import build import httplib2 # httplib2.debuglevel = 4 import pickle import pprint DISCOVERY_URI = ('http://localhost:3990/discovery/v0.2beta1/describe/' '{api}/{apiVersion}') def main(): http = httplib2.Http() service = build("buzz", "v1", http=http, discoveryServiceUrl=DISCOVERY_URI) help(service.activities().list) print service.activities().list(userId='@self', scope='@me', c='foo').uri if __name__ == '__main__': main()
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Simple command-line example for Buzz. Command-line application that retrieves the users latest content and then adds a new entry. """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' import gflags import httplib2 import logging import pprint import sys from apiclient.discovery import build from oauth2client.file import Storage from oauth2client.client import OAuth2WebServerFlow from oauth2client.tools import run FLAGS = gflags.FLAGS FLOW = OAuth2WebServerFlow( client_id='433807057907.apps.googleusercontent.com', client_secret='jigtZpMApkRxncxikFpR+SFg', scope='https://www.googleapis.com/auth/buzz', user_agent='buzz-cmdline-sample/1.0') gflags.DEFINE_enum('logging_level', 'ERROR', ['DEBUG', 'INFO', 'WARNING', 'ERROR', 'CRITICAL'], 'Set the level of logging detail.') def main(argv): try: argv = FLAGS(argv) except gflags.FlagsError, e: print '%s\\nUsage: %s ARGS\\n%s' % (e, argv[0], FLAGS) sys.exit(1) logging.getLogger().setLevel(getattr(logging, FLAGS.logging_level)) storage = Storage('buzz.dat') credentials = storage.get() if credentials is None or credentials.invalid == True: credentials = run(FLOW, storage) http = httplib2.Http() http = credentials.authorize(http) # Build the Buzz service service = build("buzz", "v1", http=http, developerKey="AIzaSyDRRpR3GS1F1_jKNNM9HCNd2wJQyPG3oN0") activities = service.activities() # Retrieve the first two activities activitylist = activities.list( max_results='2', scope='@self', userId='@me').execute() print "Retrieved the first two activities" # Retrieve the next two activities if activitylist: activitylist = activities.list_next(activitylist).execute() print "Retrieved the next two activities" # Add a new activity new_activity_body = { 'title': 'Testing insert', 'object': { 'content': u'Just a short note to show that insert is working. ☄', 'type': 'note'} } activity = activities.insert(userId='@me', body=new_activity_body).execute() print "Added a new activity" activitylist = activities.list( max_results='2', scope='@self', userId='@me').execute() # Add a comment to that activity comment_body = { "content": "This is a comment" } item = activitylist['items'][0] comment = service.comments().insert( userId=item['actor']['id'], postId=item['id'], body=comment_body ).execute() print 'Added a comment to the new activity' pprint.pprint(comment) if __name__ == '__main__': main(sys.argv)
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Simple command-line example for Buzz. Command-line application that retrieves the users latest content and then adds a new entry. """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' import gflags import httplib2 import logging import pprint import sys from apiclient.discovery import build from oauth2client.file import Storage from oauth2client.client import OAuth2WebServerFlow from oauth2client.tools import run FLAGS = gflags.FLAGS FLOW = OAuth2WebServerFlow( client_id='433807057907.apps.googleusercontent.com', client_secret='jigtZpMApkRxncxikFpR+SFg', scope='https://www.googleapis.com/auth/buzz', user_agent='buzz-cmdline-sample/1.0') gflags.DEFINE_enum('logging_level', 'ERROR', ['DEBUG', 'INFO', 'WARNING', 'ERROR', 'CRITICAL'], 'Set the level of logging detail.') def main(argv): try: argv = FLAGS(argv) except gflags.FlagsError, e: print '%s\\nUsage: %s ARGS\\n%s' % (e, argv[0], FLAGS) sys.exit(1) logging.getLogger().setLevel(getattr(logging, FLAGS.logging_level)) storage = Storage('buzz.dat') credentials = storage.get() if credentials is None or credentials.invalid == True: credentials = run(FLOW, storage) http = httplib2.Http() http = credentials.authorize(http) # Build the Buzz service service = build("buzz", "v1", http=http, developerKey="AIzaSyDRRpR3GS1F1_jKNNM9HCNd2wJQyPG3oN0") activities = service.activities() # Retrieve the first two activities activitylist = activities.list( max_results='2', scope='@self', userId='@me').execute() print "Retrieved the first two activities" # Retrieve the next two activities if activitylist: activitylist = activities.list_next(activitylist).execute() print "Retrieved the next two activities" # Add a new activity new_activity_body = { 'title': 'Testing insert', 'object': { 'content': u'Just a short note to show that insert is working. ☄', 'type': 'note'} } activity = activities.insert(userId='@me', body=new_activity_body).execute() print "Added a new activity" activitylist = activities.list( max_results='2', scope='@self', userId='@me').execute() # Add a comment to that activity comment_body = { "content": "This is a comment" } item = activitylist['items'][0] comment = service.comments().insert( userId=item['actor']['id'], postId=item['id'], body=comment_body ).execute() print 'Added a comment to the new activity' pprint.pprint(comment) if __name__ == '__main__': main(sys.argv)
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Simple command-line example for Translate. Command-line application that translates some text. """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' from apiclient.discovery import build import pprint # Uncomment the next line to get very detailed logging # httplib2.debuglevel = 4 def main(): service = build('translate', 'v2', developerKey='AIzaSyDRRpR3GS1F1_jKNNM9HCNd2wJQyPG3oN0') print service.translations().list( source='en', target='fr', q=['flower', 'car'] ).execute() if __name__ == '__main__': main()
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Simple command-line example for Translate. Command-line application that translates some text. """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' from apiclient.discovery import build import pprint # Uncomment the next line to get very detailed logging # httplib2.debuglevel = 4 def main(): service = build('translate', 'v2', developerKey='AIzaSyDRRpR3GS1F1_jKNNM9HCNd2wJQyPG3oN0') print service.translations().list( source='en', target='fr', q=['flower', 'car'] ).execute() if __name__ == '__main__': main()
Python
#!/usr/bin/env python # # Copyright 2007 Google Inc. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. # __author__ = 'jcgregorio@google.com (Joe Gregorio)' import httplib2 import logging import os import pickle from apiclient.discovery import build from oauth2client.appengine import CredentialsProperty from oauth2client.appengine import StorageByKeyName from oauth2client.client import OAuth2WebServerFlow from google.appengine.api import memcache from google.appengine.api import users from google.appengine.ext import db from google.appengine.ext import webapp from google.appengine.ext.webapp import template from google.appengine.ext.webapp import util from google.appengine.ext.webapp.util import login_required class Credentials(db.Model): credentials = CredentialsProperty() class MainHandler(webapp.RequestHandler): @login_required def get(self): user = users.get_current_user() credentials = StorageByKeyName( Credentials, user.user_id(), 'credentials').get() if credentials is None or credentials.invalid == True: flow = OAuth2WebServerFlow( client_id='2ad565600216d25d9cde', client_secret='03b56df2949a520be6049ff98b89813f17b467dc', scope='read', user_agent='oauth2client-sample/1.0', auth_uri='https://api.dailymotion.com/oauth/authorize', token_uri='https://api.dailymotion.com/oauth/token' ) callback = self.request.relative_url('/auth_return') authorize_url = flow.step1_get_authorize_url(callback) memcache.set(user.user_id(), pickle.dumps(flow)) self.redirect(authorize_url) else: http = httplib2.Http() resp, content1 = http.request('https://api.dailymotion.com/me?access_token=%s' % credentials.access_token) http = credentials.authorize(http) resp, content2 = http.request('https://api.dailymotion.com/me') path = os.path.join(os.path.dirname(__file__), 'welcome.html') logout = users.create_logout_url('/') self.response.out.write( template.render( path, { 'content1': content1, 'content2': content2, 'logout': logout })) class OAuthHandler(webapp.RequestHandler): @login_required def get(self): user = users.get_current_user() flow = pickle.loads(memcache.get(user.user_id())) if flow: credentials = flow.step2_exchange(self.request.params) StorageByKeyName( Credentials, user.user_id(), 'credentials').put(credentials) self.redirect("/") else: pass def main(): application = webapp.WSGIApplication( [ ('/', MainHandler), ('/auth_return', OAuthHandler) ], debug=True) util.run_wsgi_app(application) if __name__ == '__main__': main()
Python
#!/usr/bin/env python # Copyright (c) 2010, Google Inc. # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. """Module to enforce different constraints on flags. A validator represents an invariant, enforced over a one or more flags. See 'FLAGS VALIDATORS' in flags.py's docstring for a usage manual. """ __author__ = 'olexiy@google.com (Olexiy Oryeshko)' class Error(Exception): """Thrown If validator constraint is not satisfied.""" class Validator(object): """Base class for flags validators. Users should NOT overload these classes, and use flags.Register... methods instead. """ # Used to assign each validator an unique insertion_index validators_count = 0 def __init__(self, checker, message): """Constructor to create all validators. Args: checker: function to verify the constraint. Input of this method varies, see SimpleValidator and DictionaryValidator for a detailed description. message: string, error message to be shown to the user """ self.checker = checker self.message = message Validator.validators_count += 1 # Used to assert validators in the order they were registered (CL/18694236) self.insertion_index = Validator.validators_count def Verify(self, flag_values): """Verify that constraint is satisfied. flags library calls this method to verify Validator's constraint. Args: flag_values: flags.FlagValues, containing all flags Raises: Error: if constraint is not satisfied. """ param = self._GetInputToCheckerFunction(flag_values) if not self.checker(param): raise Error(self.message) def GetFlagsNames(self): """Return the names of the flags checked by this validator. Returns: [string], names of the flags """ raise NotImplementedError('This method should be overloaded') def PrintFlagsWithValues(self, flag_values): raise NotImplementedError('This method should be overloaded') def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues, containing all flags. Returns: Return type depends on the specific validator. """ raise NotImplementedError('This method should be overloaded') class SimpleValidator(Validator): """Validator behind RegisterValidator() method. Validates that a single flag passes its checker function. The checker function takes the flag value and returns True (if value looks fine) or, if flag value is not valid, either returns False or raises an Exception.""" def __init__(self, flag_name, checker, message): """Constructor. Args: flag_name: string, name of the flag. checker: function to verify the validator. input - value of the corresponding flag (string, boolean, etc). output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise Error. message: string, error message to be shown to the user if validator's condition is not satisfied """ super(SimpleValidator, self).__init__(checker, message) self.flag_name = flag_name def GetFlagsNames(self): return [self.flag_name] def PrintFlagsWithValues(self, flag_values): return 'flag --%s=%s' % (self.flag_name, flag_values[self.flag_name].value) def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues Returns: value of the corresponding flag. """ return flag_values[self.flag_name].value class DictionaryValidator(Validator): """Validator behind RegisterDictionaryValidator method. Validates that flag values pass their common checker function. The checker function takes flag values and returns True (if values look fine) or, if values are not valid, either returns False or raises an Exception. """ def __init__(self, flag_names, checker, message): """Constructor. Args: flag_names: [string], containing names of the flags used by checker. checker: function to verify the validator. input - dictionary, with keys() being flag_names, and value for each key being the value of the corresponding flag (string, boolean, etc). output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise Error. message: string, error message to be shown to the user if validator's condition is not satisfied """ super(DictionaryValidator, self).__init__(checker, message) self.flag_names = flag_names def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues Returns: dictionary, with keys() being self.lag_names, and value for each key being the value of the corresponding flag (string, boolean, etc). """ return dict([key, flag_values[key].value] for key in self.flag_names) def PrintFlagsWithValues(self, flag_values): prefix = 'flags ' flags_with_values = [] for key in self.flag_names: flags_with_values.append('%s=%s' % (key, flag_values[key].value)) return prefix + ', '.join(flags_with_values) def GetFlagsNames(self): return self.flag_names
Python
#!/usr/bin/env python # # Copyright 2007 Google Inc. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. # __author__ = 'jcgregorio@google.com (Joe Gregorio)' import httplib2 import logging import os import pickle from apiclient.discovery import build from oauth2client.appengine import CredentialsProperty from oauth2client.appengine import StorageByKeyName from oauth2client.client import OAuth2WebServerFlow from google.appengine.api import memcache from google.appengine.api import users from google.appengine.ext import db from google.appengine.ext import webapp from google.appengine.ext.webapp import template from google.appengine.ext.webapp import util from google.appengine.ext.webapp.util import login_required class Credentials(db.Model): credentials = CredentialsProperty() class MainHandler(webapp.RequestHandler): @login_required def get(self): user = users.get_current_user() credentials = StorageByKeyName( Credentials, user.user_id(), 'credentials').get() if credentials is None or credentials.invalid == True: flow = OAuth2WebServerFlow( client_id='2ad565600216d25d9cde', client_secret='03b56df2949a520be6049ff98b89813f17b467dc', scope='read', user_agent='oauth2client-sample/1.0', auth_uri='https://api.dailymotion.com/oauth/authorize', token_uri='https://api.dailymotion.com/oauth/token' ) callback = self.request.relative_url('/auth_return') authorize_url = flow.step1_get_authorize_url(callback) memcache.set(user.user_id(), pickle.dumps(flow)) self.redirect(authorize_url) else: http = httplib2.Http() resp, content1 = http.request('https://api.dailymotion.com/me?access_token=%s' % credentials.access_token) http = credentials.authorize(http) resp, content2 = http.request('https://api.dailymotion.com/me') path = os.path.join(os.path.dirname(__file__), 'welcome.html') logout = users.create_logout_url('/') self.response.out.write( template.render( path, { 'content1': content1, 'content2': content2, 'logout': logout })) class OAuthHandler(webapp.RequestHandler): @login_required def get(self): user = users.get_current_user() flow = pickle.loads(memcache.get(user.user_id())) if flow: credentials = flow.step2_exchange(self.request.params) StorageByKeyName( Credentials, user.user_id(), 'credentials').put(credentials) self.redirect("/") else: pass def main(): application = webapp.WSGIApplication( [ ('/', MainHandler), ('/auth_return', OAuthHandler) ], debug=True) util.run_wsgi_app(application) if __name__ == '__main__': main()
Python
#!/usr/bin/env python # Copyright (c) 2007, Google Inc. # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. # # --- # Author: Chad Lester # Design and style contributions by: # Amit Patel, Bogdan Cocosel, Daniel Dulitz, Eric Tiedemann, # Eric Veach, Laurence Gonsalves, Matthew Springer # Code reorganized a bit by Craig Silverstein """This module is used to define and parse command line flags. This module defines a *distributed* flag-definition policy: rather than an application having to define all flags in or near main(), each python module defines flags that are useful to it. When one python module imports another, it gains access to the other's flags. (This is implemented by having all modules share a common, global registry object containing all the flag information.) Flags are defined through the use of one of the DEFINE_xxx functions. The specific function used determines how the flag is parsed, checked, and optionally type-converted, when it's seen on the command line. IMPLEMENTATION: DEFINE_* creates a 'Flag' object and registers it with a 'FlagValues' object (typically the global FlagValues FLAGS, defined here). The 'FlagValues' object can scan the command line arguments and pass flag arguments to the corresponding 'Flag' objects for value-checking and type conversion. The converted flag values are available as attributes of the 'FlagValues' object. Code can access the flag through a FlagValues object, for instance gflags.FLAGS.myflag. Typically, the __main__ module passes the command line arguments to gflags.FLAGS for parsing. At bottom, this module calls getopt(), so getopt functionality is supported, including short- and long-style flags, and the use of -- to terminate flags. Methods defined by the flag module will throw 'FlagsError' exceptions. The exception argument will be a human-readable string. FLAG TYPES: This is a list of the DEFINE_*'s that you can do. All flags take a name, default value, help-string, and optional 'short' name (one-letter name). Some flags have other arguments, which are described with the flag. DEFINE_string: takes any input, and interprets it as a string. DEFINE_bool or DEFINE_boolean: typically does not take an argument: say --myflag to set FLAGS.myflag to true, or --nomyflag to set FLAGS.myflag to false. Alternately, you can say --myflag=true or --myflag=t or --myflag=1 or --myflag=false or --myflag=f or --myflag=0 DEFINE_float: takes an input and interprets it as a floating point number. Takes optional args lower_bound and upper_bound; if the number specified on the command line is out of range, it will raise a FlagError. DEFINE_integer: takes an input and interprets it as an integer. Takes optional args lower_bound and upper_bound as for floats. DEFINE_enum: takes a list of strings which represents legal values. If the command-line value is not in this list, raise a flag error. Otherwise, assign to FLAGS.flag as a string. DEFINE_list: Takes a comma-separated list of strings on the commandline. Stores them in a python list object. DEFINE_spaceseplist: Takes a space-separated list of strings on the commandline. Stores them in a python list object. Example: --myspacesepflag "foo bar baz" DEFINE_multistring: The same as DEFINE_string, except the flag can be specified more than once on the commandline. The result is a python list object (list of strings), even if the flag is only on the command line once. DEFINE_multi_int: The same as DEFINE_integer, except the flag can be specified more than once on the commandline. The result is a python list object (list of ints), even if the flag is only on the command line once. SPECIAL FLAGS: There are a few flags that have special meaning: --help prints a list of all the flags in a human-readable fashion --helpshort prints a list of all key flags (see below). --helpxml prints a list of all flags, in XML format. DO NOT parse the output of --help and --helpshort. Instead, parse the output of --helpxml. For more info, see "OUTPUT FOR --helpxml" below. --flagfile=foo read flags from file foo. --undefok=f1,f2 ignore unrecognized option errors for f1,f2. For boolean flags, you should use --undefok=boolflag, and --boolflag and --noboolflag will be accepted. Do not use --undefok=noboolflag. -- as in getopt(), terminates flag-processing FLAGS VALIDATORS: If your program: - requires flag X to be specified - needs flag Y to match a regular expression - or requires any more general constraint to be satisfied then validators are for you! Each validator represents a constraint over one flag, which is enforced starting from the initial parsing of the flags and until the program terminates. Also, lower_bound and upper_bound for numerical flags are enforced using flag validators. Howto: If you want to enforce a constraint over one flag, use flags.RegisterValidator(flag_name, checker, message='Flag validation failed', flag_values=FLAGS) After flag values are initially parsed, and after any change to the specified flag, method checker(flag_value) will be executed. If constraint is not satisfied, an IllegalFlagValue exception will be raised. See RegisterValidator's docstring for a detailed explanation on how to construct your own checker. EXAMPLE USAGE: FLAGS = flags.FLAGS flags.DEFINE_integer('my_version', 0, 'Version number.') flags.DEFINE_string('filename', None, 'Input file name', short_name='f') flags.RegisterValidator('my_version', lambda value: value % 2 == 0, message='--my_version must be divisible by 2') flags.MarkFlagAsRequired('filename') NOTE ON --flagfile: Flags may be loaded from text files in addition to being specified on the commandline. Any flags you don't feel like typing, throw them in a file, one flag per line, for instance: --myflag=myvalue --nomyboolean_flag You then specify your file with the special flag '--flagfile=somefile'. You CAN recursively nest flagfile= tokens OR use multiple files on the command line. Lines beginning with a single hash '#' or a double slash '//' are comments in your flagfile. Any flagfile=<file> will be interpreted as having a relative path from the current working directory rather than from the place the file was included from: myPythonScript.py --flagfile=config/somefile.cfg If somefile.cfg includes further --flagfile= directives, these will be referenced relative to the original CWD, not from the directory the including flagfile was found in! The caveat applies to people who are including a series of nested files in a different dir than they are executing out of. Relative path names are always from CWD, not from the directory of the parent include flagfile. We do now support '~' expanded directory names. Absolute path names ALWAYS work! EXAMPLE USAGE: import gflags FLAGS = gflags.FLAGS # Flag names are globally defined! So in general, we need to be # careful to pick names that are unlikely to be used by other libraries. # If there is a conflict, we'll get an error at import time. gflags.DEFINE_string('name', 'Mr. President', 'your name') gflags.DEFINE_integer('age', None, 'your age in years', lower_bound=0) gflags.DEFINE_boolean('debug', False, 'produces debugging output') gflags.DEFINE_enum('gender', 'male', ['male', 'female'], 'your gender') def main(argv): try: argv = FLAGS(argv) # parse flags except gflags.FlagsError, e: print '%s\\nUsage: %s ARGS\\n%s' % (e, sys.argv[0], FLAGS) sys.exit(1) if FLAGS.debug: print 'non-flag arguments:', argv print 'Happy Birthday', FLAGS.name if FLAGS.age is not None: print 'You are a %s, who is %d years old' % (FLAGS.gender, FLAGS.age) if __name__ == '__main__': main(sys.argv) KEY FLAGS: As we already explained, each module gains access to all flags defined by all the other modules it transitively imports. In the case of non-trivial scripts, this means a lot of flags ... For documentation purposes, it is good to identify the flags that are key (i.e., really important) to a module. Clearly, the concept of "key flag" is a subjective one. When trying to determine whether a flag is key to a module or not, assume that you are trying to explain your module to a potential user: which flags would you really like to mention first? We'll describe shortly how to declare which flags are key to a module. For the moment, assume we know the set of key flags for each module. Then, if you use the app.py module, you can use the --helpshort flag to print only the help for the flags that are key to the main module, in a human-readable format. NOTE: If you need to parse the flag help, do NOT use the output of --help / --helpshort. That output is meant for human consumption, and may be changed in the future. Instead, use --helpxml; flags that are key for the main module are marked there with a <key>yes</key> element. The set of key flags for a module M is composed of: 1. Flags defined by module M by calling a DEFINE_* function. 2. Flags that module M explictly declares as key by using the function DECLARE_key_flag(<flag_name>) 3. Key flags of other modules that M specifies by using the function ADOPT_module_key_flags(<other_module>) This is a "bulk" declaration of key flags: each flag that is key for <other_module> becomes key for the current module too. Notice that if you do not use the functions described at points 2 and 3 above, then --helpshort prints information only about the flags defined by the main module of our script. In many cases, this behavior is good enough. But if you move part of the main module code (together with the related flags) into a different module, then it is nice to use DECLARE_key_flag / ADOPT_module_key_flags and make sure --helpshort lists all relevant flags (otherwise, your code refactoring may confuse your users). Note: each of DECLARE_key_flag / ADOPT_module_key_flags has its own pluses and minuses: DECLARE_key_flag is more targeted and may lead a more focused --helpshort documentation. ADOPT_module_key_flags is good for cases when an entire module is considered key to the current script. Also, it does not require updates to client scripts when a new flag is added to the module. EXAMPLE USAGE 2 (WITH KEY FLAGS): Consider an application that contains the following three files (two auxiliary modules and a main module): File libfoo.py: import gflags gflags.DEFINE_integer('num_replicas', 3, 'Number of replicas to start') gflags.DEFINE_boolean('rpc2', True, 'Turn on the usage of RPC2.') ... some code ... File libbar.py: import gflags gflags.DEFINE_string('bar_gfs_path', '/gfs/path', 'Path to the GFS files for libbar.') gflags.DEFINE_string('email_for_bar_errors', 'bar-team@google.com', 'Email address for bug reports about module libbar.') gflags.DEFINE_boolean('bar_risky_hack', False, 'Turn on an experimental and buggy optimization.') ... some code ... File myscript.py: import gflags import libfoo import libbar gflags.DEFINE_integer('num_iterations', 0, 'Number of iterations.') # Declare that all flags that are key for libfoo are # key for this module too. gflags.ADOPT_module_key_flags(libfoo) # Declare that the flag --bar_gfs_path (defined in libbar) is key # for this module. gflags.DECLARE_key_flag('bar_gfs_path') ... some code ... When myscript is invoked with the flag --helpshort, the resulted help message lists information about all the key flags for myscript: --num_iterations, --num_replicas, --rpc2, and --bar_gfs_path (in addition to the special flags --help and --helpshort). Of course, myscript uses all the flags declared by it (in this case, just --num_replicas) or by any of the modules it transitively imports (e.g., the modules libfoo, libbar). E.g., it can access the value of FLAGS.bar_risky_hack, even if --bar_risky_hack is not declared as a key flag for myscript. OUTPUT FOR --helpxml: The --helpxml flag generates output with the following structure: <?xml version="1.0"?> <AllFlags> <program>PROGRAM_BASENAME</program> <usage>MAIN_MODULE_DOCSTRING</usage> (<flag> [<key>yes</key>] <file>DECLARING_MODULE</file> <name>FLAG_NAME</name> <meaning>FLAG_HELP_MESSAGE</meaning> <default>DEFAULT_FLAG_VALUE</default> <current>CURRENT_FLAG_VALUE</current> <type>FLAG_TYPE</type> [OPTIONAL_ELEMENTS] </flag>)* </AllFlags> Notes: 1. The output is intentionally similar to the output generated by the C++ command-line flag library. The few differences are due to the Python flags that do not have a C++ equivalent (at least not yet), e.g., DEFINE_list. 2. New XML elements may be added in the future. 3. DEFAULT_FLAG_VALUE is in serialized form, i.e., the string you can pass for this flag on the command-line. E.g., for a flag defined using DEFINE_list, this field may be foo,bar, not ['foo', 'bar']. 4. CURRENT_FLAG_VALUE is produced using str(). This means that the string 'false' will be represented in the same way as the boolean False. Using repr() would have removed this ambiguity and simplified parsing, but would have broken the compatibility with the C++ command-line flags. 5. OPTIONAL_ELEMENTS describe elements relevant for certain kinds of flags: lower_bound, upper_bound (for flags that specify bounds), enum_value (for enum flags), list_separator (for flags that consist of a list of values, separated by a special token). 6. We do not provide any example here: please use --helpxml instead. """ import cgi import getopt import os import re import string import sys import gflags_validators # Are we running at least python 2.2? try: if tuple(sys.version_info[:3]) < (2,2,0): raise NotImplementedError("requires python 2.2.0 or later") except AttributeError: # a very old python, that lacks sys.version_info raise NotImplementedError("requires python 2.2.0 or later") # If we're not running at least python 2.2.1, define True, False, and bool. # Thanks, Guido, for the code. try: True, False, bool except NameError: False = 0 True = 1 def bool(x): if x: return True else: return False # Are we running under pychecker? _RUNNING_PYCHECKER = 'pychecker.python' in sys.modules def _GetCallingModule(): """Returns the name of the module that's calling into this module. We generally use this function to get the name of the module calling a DEFINE_foo... function. """ # Walk down the stack to find the first globals dict that's not ours. for depth in range(1, sys.getrecursionlimit()): if not sys._getframe(depth).f_globals is globals(): globals_for_frame = sys._getframe(depth).f_globals module_name = _GetModuleObjectAndName(globals_for_frame)[1] if module_name is not None: return module_name raise AssertionError("No module was found") def _GetThisModuleObjectAndName(): """Returns: (module object, module name) for this module.""" return _GetModuleObjectAndName(globals()) # module exceptions: class FlagsError(Exception): """The base class for all flags errors.""" pass class DuplicateFlag(FlagsError): """Raised if there is a flag naming conflict.""" pass class DuplicateFlagCannotPropagateNoneToSwig(DuplicateFlag): """Special case of DuplicateFlag -- SWIG flag value can't be set to None. This can be raised when a duplicate flag is created. Even if allow_override is True, we still abort if the new value is None, because it's currently impossible to pass None default value back to SWIG. See FlagValues.SetDefault for details. """ pass # A DuplicateFlagError conveys more information than a # DuplicateFlag. Since there are external modules that create # DuplicateFlags, the interface to DuplicateFlag shouldn't change. class DuplicateFlagError(DuplicateFlag): def __init__(self, flagname, flag_values): self.flagname = flagname message = "The flag '%s' is defined twice." % self.flagname flags_by_module = flag_values.FlagsByModuleDict() for module in flags_by_module: for flag in flags_by_module[module]: if flag.name == flagname or flag.short_name == flagname: message = message + " First from " + module + "," break message = message + " Second from " + _GetCallingModule() DuplicateFlag.__init__(self, message) class IllegalFlagValue(FlagsError): """The flag command line argument is illegal.""" pass class UnrecognizedFlag(FlagsError): """Raised if a flag is unrecognized.""" pass # An UnrecognizedFlagError conveys more information than an UnrecognizedFlag. # Since there are external modules that create DuplicateFlags, the interface to # DuplicateFlag shouldn't change. The flagvalue will be assigned the full value # of the flag and its argument, if any, allowing handling of unrecognzed flags # in an exception handler. # If flagvalue is the empty string, then this exception is an due to a # reference to a flag that was not already defined. class UnrecognizedFlagError(UnrecognizedFlag): def __init__(self, flagname, flagvalue=''): self.flagname = flagname self.flagvalue = flagvalue UnrecognizedFlag.__init__( self, "Unknown command line flag '%s'" % flagname) # Global variable used by expvar _exported_flags = {} _help_width = 80 # width of help output def GetHelpWidth(): """Returns: an integer, the width of help lines that is used in TextWrap.""" return _help_width def CutCommonSpacePrefix(text): """Removes a common space prefix from the lines of a multiline text. If the first line does not start with a space, it is left as it is and only in the remaining lines a common space prefix is being searched for. That means the first line will stay untouched. This is especially useful to turn doc strings into help texts. This is because some people prefer to have the doc comment start already after the apostrophy and then align the following lines while others have the apostrophies on a seperately line. The function also drops trailing empty lines and ignores empty lines following the initial content line while calculating the initial common whitespace. Args: text: text to work on Returns: the resulting text """ text_lines = text.splitlines() # Drop trailing empty lines while text_lines and not text_lines[-1]: text_lines = text_lines[:-1] if text_lines: # We got some content, is the first line starting with a space? if text_lines[0] and text_lines[0][0].isspace(): text_first_line = [] else: text_first_line = [text_lines.pop(0)] # Calculate length of common leading whitesppace (only over content lines) common_prefix = os.path.commonprefix([line for line in text_lines if line]) space_prefix_len = len(common_prefix) - len(common_prefix.lstrip()) # If we have a common space prefix, drop it from all lines if space_prefix_len: for index in xrange(len(text_lines)): if text_lines[index]: text_lines[index] = text_lines[index][space_prefix_len:] return '\n'.join(text_first_line + text_lines) return '' def TextWrap(text, length=None, indent='', firstline_indent=None, tabs=' '): """Wraps a given text to a maximum line length and returns it. We turn lines that only contain whitespaces into empty lines. We keep new lines and tabs (e.g., we do not treat tabs as spaces). Args: text: text to wrap length: maximum length of a line, includes indentation if this is None then use GetHelpWidth() indent: indent for all but first line firstline_indent: indent for first line; if None, fall back to indent tabs: replacement for tabs Returns: wrapped text Raises: FlagsError: if indent not shorter than length FlagsError: if firstline_indent not shorter than length """ # Get defaults where callee used None if length is None: length = GetHelpWidth() if indent is None: indent = '' if len(indent) >= length: raise FlagsError('Indent must be shorter than length') # In line we will be holding the current line which is to be started # with indent (or firstline_indent if available) and then appended # with words. if firstline_indent is None: firstline_indent = '' line = indent else: line = firstline_indent if len(firstline_indent) >= length: raise FlagsError('First iline indent must be shorter than length') # If the callee does not care about tabs we simply convert them to # spaces If callee wanted tabs to be single space then we do that # already here. if not tabs or tabs == ' ': text = text.replace('\t', ' ') else: tabs_are_whitespace = not tabs.strip() line_regex = re.compile('([ ]*)(\t*)([^ \t]+)', re.MULTILINE) # Split the text into lines and the lines with the regex above. The # resulting lines are collected in result[]. For each split we get the # spaces, the tabs and the next non white space (e.g. next word). result = [] for text_line in text.splitlines(): # Store result length so we can find out whether processing the next # line gave any new content old_result_len = len(result) # Process next line with line_regex. For optimization we do an rstrip(). # - process tabs (changes either line or word, see below) # - process word (first try to squeeze on line, then wrap or force wrap) # Spaces found on the line are ignored, they get added while wrapping as # needed. for spaces, current_tabs, word in line_regex.findall(text_line.rstrip()): # If tabs weren't converted to spaces, handle them now if current_tabs: # If the last thing we added was a space anyway then drop # it. But let's not get rid of the indentation. if (((result and line != indent) or (not result and line != firstline_indent)) and line[-1] == ' '): line = line[:-1] # Add the tabs, if that means adding whitespace, just add it at # the line, the rstrip() code while shorten the line down if # necessary if tabs_are_whitespace: line += tabs * len(current_tabs) else: # if not all tab replacement is whitespace we prepend it to the word word = tabs * len(current_tabs) + word # Handle the case where word cannot be squeezed onto current last line if len(line) + len(word) > length and len(indent) + len(word) <= length: result.append(line.rstrip()) line = indent + word word = '' # No space left on line or can we append a space? if len(line) + 1 >= length: result.append(line.rstrip()) line = indent else: line += ' ' # Add word and shorten it up to allowed line length. Restart next # line with indent and repeat, or add a space if we're done (word # finished) This deals with words that caanot fit on one line # (e.g. indent + word longer than allowed line length). while len(line) + len(word) >= length: line += word result.append(line[:length]) word = line[length:] line = indent # Default case, simply append the word and a space if word: line += word + ' ' # End of input line. If we have content we finish the line. If the # current line is just the indent but we had content in during this # original line then we need to add an emoty line. if (result and line != indent) or (not result and line != firstline_indent): result.append(line.rstrip()) elif len(result) == old_result_len: result.append('') line = indent return '\n'.join(result) def DocToHelp(doc): """Takes a __doc__ string and reformats it as help.""" # Get rid of starting and ending white space. Using lstrip() or even # strip() could drop more than maximum of first line and right space # of last line. doc = doc.strip() # Get rid of all empty lines whitespace_only_line = re.compile('^[ \t]+$', re.M) doc = whitespace_only_line.sub('', doc) # Cut out common space at line beginnings doc = CutCommonSpacePrefix(doc) # Just like this module's comment, comments tend to be aligned somehow. # In other words they all start with the same amount of white space # 1) keep double new lines # 2) keep ws after new lines if not empty line # 3) all other new lines shall be changed to a space # Solution: Match new lines between non white space and replace with space. doc = re.sub('(?<=\S)\n(?=\S)', ' ', doc, re.M) return doc def _GetModuleObjectAndName(globals_dict): """Returns the module that defines a global environment, and its name. Args: globals_dict: A dictionary that should correspond to an environment providing the values of the globals. Returns: A pair consisting of (1) module object and (2) module name (a string). Returns (None, None) if the module could not be identified. """ # The use of .items() (instead of .iteritems()) is NOT a mistake: if # a parallel thread imports a module while we iterate over # .iteritems() (not nice, but possible), we get a RuntimeError ... # Hence, we use the slightly slower but safer .items(). for name, module in sys.modules.items(): if getattr(module, '__dict__', None) is globals_dict: if name == '__main__': # Pick a more informative name for the main module. name = sys.argv[0] return (module, name) return (None, None) def _GetMainModule(): """Returns the name of the module from which execution started.""" for depth in range(1, sys.getrecursionlimit()): try: globals_of_main = sys._getframe(depth).f_globals except ValueError: return _GetModuleObjectAndName(globals_of_main)[1] raise AssertionError("No module was found") class FlagValues: """Registry of 'Flag' objects. A 'FlagValues' can then scan command line arguments, passing flag arguments through to the 'Flag' objects that it owns. It also provides easy access to the flag values. Typically only one 'FlagValues' object is needed by an application: gflags.FLAGS This class is heavily overloaded: 'Flag' objects are registered via __setitem__: FLAGS['longname'] = x # register a new flag The .value attribute of the registered 'Flag' objects can be accessed as attributes of this 'FlagValues' object, through __getattr__. Both the long and short name of the original 'Flag' objects can be used to access its value: FLAGS.longname # parsed flag value FLAGS.x # parsed flag value (short name) Command line arguments are scanned and passed to the registered 'Flag' objects through the __call__ method. Unparsed arguments, including argv[0] (e.g. the program name) are returned. argv = FLAGS(sys.argv) # scan command line arguments The original registered Flag objects can be retrieved through the use of the dictionary-like operator, __getitem__: x = FLAGS['longname'] # access the registered Flag object The str() operator of a 'FlagValues' object provides help for all of the registered 'Flag' objects. """ def __init__(self): # Since everything in this class is so heavily overloaded, the only # way of defining and using fields is to access __dict__ directly. # Dictionary: flag name (string) -> Flag object. self.__dict__['__flags'] = {} # Dictionary: module name (string) -> list of Flag objects that are defined # by that module. self.__dict__['__flags_by_module'] = {} # Dictionary: module name (string) -> list of Flag objects that are # key for that module. self.__dict__['__key_flags_by_module'] = {} # Set if we should use new style gnu_getopt rather than getopt when parsing # the args. Only possible with Python 2.3+ self.UseGnuGetOpt(False) def UseGnuGetOpt(self, use_gnu_getopt=True): self.__dict__['__use_gnu_getopt'] = use_gnu_getopt def IsGnuGetOpt(self): return self.__dict__['__use_gnu_getopt'] def FlagDict(self): return self.__dict__['__flags'] def FlagsByModuleDict(self): """Returns the dictionary of module_name -> list of defined flags. Returns: A dictionary. Its keys are module names (strings). Its values are lists of Flag objects. """ return self.__dict__['__flags_by_module'] def KeyFlagsByModuleDict(self): """Returns the dictionary of module_name -> list of key flags. Returns: A dictionary. Its keys are module names (strings). Its values are lists of Flag objects. """ return self.__dict__['__key_flags_by_module'] def _RegisterFlagByModule(self, module_name, flag): """Records the module that defines a specific flag. We keep track of which flag is defined by which module so that we can later sort the flags by module. Args: module_name: A string, the name of a Python module. flag: A Flag object, a flag that is key to the module. """ flags_by_module = self.FlagsByModuleDict() flags_by_module.setdefault(module_name, []).append(flag) def _RegisterKeyFlagForModule(self, module_name, flag): """Specifies that a flag is a key flag for a module. Args: module_name: A string, the name of a Python module. flag: A Flag object, a flag that is key to the module. """ key_flags_by_module = self.KeyFlagsByModuleDict() # The list of key flags for the module named module_name. key_flags = key_flags_by_module.setdefault(module_name, []) # Add flag, but avoid duplicates. if flag not in key_flags: key_flags.append(flag) def _GetFlagsDefinedByModule(self, module): """Returns the list of flags defined by a module. Args: module: A module object or a module name (a string). Returns: A new list of Flag objects. Caller may update this list as he wishes: none of those changes will affect the internals of this FlagValue object. """ if not isinstance(module, str): module = module.__name__ return list(self.FlagsByModuleDict().get(module, [])) def _GetKeyFlagsForModule(self, module): """Returns the list of key flags for a module. Args: module: A module object or a module name (a string) Returns: A new list of Flag objects. Caller may update this list as he wishes: none of those changes will affect the internals of this FlagValue object. """ if not isinstance(module, str): module = module.__name__ # Any flag is a key flag for the module that defined it. NOTE: # key_flags is a fresh list: we can update it without affecting the # internals of this FlagValues object. key_flags = self._GetFlagsDefinedByModule(module) # Take into account flags explicitly declared as key for a module. for flag in self.KeyFlagsByModuleDict().get(module, []): if flag not in key_flags: key_flags.append(flag) return key_flags def AppendFlagValues(self, flag_values): """Appends flags registered in another FlagValues instance. Args: flag_values: registry to copy from """ for flag_name, flag in flag_values.FlagDict().iteritems(): # Each flags with shortname appears here twice (once under its # normal name, and again with its short name). To prevent # problems (DuplicateFlagError) with double flag registration, we # perform a check to make sure that the entry we're looking at is # for its normal name. if flag_name == flag.name: self[flag_name] = flag def RemoveFlagValues(self, flag_values): """Remove flags that were previously appended from another FlagValues. Args: flag_values: registry containing flags to remove. """ for flag_name in flag_values.FlagDict(): self.__delattr__(flag_name) def __setitem__(self, name, flag): """Registers a new flag variable.""" fl = self.FlagDict() if not isinstance(flag, Flag): raise IllegalFlagValue(flag) if not isinstance(name, type("")): raise FlagsError("Flag name must be a string") if len(name) == 0: raise FlagsError("Flag name cannot be empty") # If running under pychecker, duplicate keys are likely to be # defined. Disable check for duplicate keys when pycheck'ing. if (fl.has_key(name) and not flag.allow_override and not fl[name].allow_override and not _RUNNING_PYCHECKER): raise DuplicateFlagError(name, self) short_name = flag.short_name if short_name is not None: if (fl.has_key(short_name) and not flag.allow_override and not fl[short_name].allow_override and not _RUNNING_PYCHECKER): raise DuplicateFlagError(short_name, self) fl[short_name] = flag fl[name] = flag global _exported_flags _exported_flags[name] = flag def __getitem__(self, name): """Retrieves the Flag object for the flag --name.""" return self.FlagDict()[name] def __getattr__(self, name): """Retrieves the 'value' attribute of the flag --name.""" fl = self.FlagDict() if not fl.has_key(name): raise AttributeError(name) return fl[name].value def __setattr__(self, name, value): """Sets the 'value' attribute of the flag --name.""" fl = self.FlagDict() fl[name].value = value self._AssertValidators(fl[name].validators) return value def _AssertAllValidators(self): all_validators = set() for flag in self.FlagDict().itervalues(): for validator in flag.validators: all_validators.add(validator) self._AssertValidators(all_validators) def _AssertValidators(self, validators): """Assert if all validators in the list are satisfied. Asserts validators in the order they were created. Args: validators: Iterable(gflags_validators.Validator), validators to be verified Raises: AttributeError: if validators work with a non-existing flag. IllegalFlagValue: if validation fails for at least one validator """ for validator in sorted( validators, key=lambda validator: validator.insertion_index): try: validator.Verify(self) except gflags_validators.Error, e: message = validator.PrintFlagsWithValues(self) raise IllegalFlagValue('%s: %s' % (message, str(e))) def _FlagIsRegistered(self, flag_obj): """Checks whether a Flag object is registered under some name. Note: this is non trivial: in addition to its normal name, a flag may have a short name too. In self.FlagDict(), both the normal and the short name are mapped to the same flag object. E.g., calling only "del FLAGS.short_name" is not unregistering the corresponding Flag object (it is still registered under the longer name). Args: flag_obj: A Flag object. Returns: A boolean: True iff flag_obj is registered under some name. """ flag_dict = self.FlagDict() # Check whether flag_obj is registered under its long name. name = flag_obj.name if flag_dict.get(name, None) == flag_obj: return True # Check whether flag_obj is registered under its short name. short_name = flag_obj.short_name if (short_name is not None and flag_dict.get(short_name, None) == flag_obj): return True # The flag cannot be registered under any other name, so we do not # need to do a full search through the values of self.FlagDict(). return False def __delattr__(self, flag_name): """Deletes a previously-defined flag from a flag object. This method makes sure we can delete a flag by using del flag_values_object.<flag_name> E.g., flags.DEFINE_integer('foo', 1, 'Integer flag.') del flags.FLAGS.foo Args: flag_name: A string, the name of the flag to be deleted. Raises: AttributeError: When there is no registered flag named flag_name. """ fl = self.FlagDict() if flag_name not in fl: raise AttributeError(flag_name) flag_obj = fl[flag_name] del fl[flag_name] if not self._FlagIsRegistered(flag_obj): # If the Flag object indicated by flag_name is no longer # registered (please see the docstring of _FlagIsRegistered), then # we delete the occurences of the flag object in all our internal # dictionaries. self.__RemoveFlagFromDictByModule(self.FlagsByModuleDict(), flag_obj) self.__RemoveFlagFromDictByModule(self.KeyFlagsByModuleDict(), flag_obj) def __RemoveFlagFromDictByModule(self, flags_by_module_dict, flag_obj): """Removes a flag object from a module -> list of flags dictionary. Args: flags_by_module_dict: A dictionary that maps module names to lists of flags. flag_obj: A flag object. """ for unused_module, flags_in_module in flags_by_module_dict.iteritems(): # while (as opposed to if) takes care of multiple occurences of a # flag in the list for the same module. while flag_obj in flags_in_module: flags_in_module.remove(flag_obj) def SetDefault(self, name, value): """Changes the default value of the named flag object.""" fl = self.FlagDict() if not fl.has_key(name): raise AttributeError(name) fl[name].SetDefault(value) self._AssertValidators(fl[name].validators) def __contains__(self, name): """Returns True if name is a value (flag) in the dict.""" return name in self.FlagDict() has_key = __contains__ # a synonym for __contains__() def __iter__(self): return self.FlagDict().iterkeys() def __call__(self, argv): """Parses flags from argv; stores parsed flags into this FlagValues object. All unparsed arguments are returned. Flags are parsed using the GNU Program Argument Syntax Conventions, using getopt: http://www.gnu.org/software/libc/manual/html_mono/libc.html#Getopt Args: argv: argument list. Can be of any type that may be converted to a list. Returns: The list of arguments not parsed as options, including argv[0] Raises: FlagsError: on any parsing error """ # Support any sequence type that can be converted to a list argv = list(argv) shortopts = "" longopts = [] fl = self.FlagDict() # This pre parses the argv list for --flagfile=<> options. argv = argv[:1] + self.ReadFlagsFromFiles(argv[1:], force_gnu=False) # Correct the argv to support the google style of passing boolean # parameters. Boolean parameters may be passed by using --mybool, # --nomybool, --mybool=(true|false|1|0). getopt does not support # having options that may or may not have a parameter. We replace # instances of the short form --mybool and --nomybool with their # full forms: --mybool=(true|false). original_argv = list(argv) # list() makes a copy shortest_matches = None for name, flag in fl.items(): if not flag.boolean: continue if shortest_matches is None: # Determine the smallest allowable prefix for all flag names shortest_matches = self.ShortestUniquePrefixes(fl) no_name = 'no' + name prefix = shortest_matches[name] no_prefix = shortest_matches[no_name] # Replace all occurences of this boolean with extended forms for arg_idx in range(1, len(argv)): arg = argv[arg_idx] if arg.find('=') >= 0: continue if arg.startswith('--'+prefix) and ('--'+name).startswith(arg): argv[arg_idx] = ('--%s=true' % name) elif arg.startswith('--'+no_prefix) and ('--'+no_name).startswith(arg): argv[arg_idx] = ('--%s=false' % name) # Loop over all of the flags, building up the lists of short options # and long options that will be passed to getopt. Short options are # specified as a string of letters, each letter followed by a colon # if it takes an argument. Long options are stored in an array of # strings. Each string ends with an '=' if it takes an argument. for name, flag in fl.items(): longopts.append(name + "=") if len(name) == 1: # one-letter option: allow short flag type also shortopts += name if not flag.boolean: shortopts += ":" longopts.append('undefok=') undefok_flags = [] # In case --undefok is specified, loop to pick up unrecognized # options one by one. unrecognized_opts = [] args = argv[1:] while True: try: if self.__dict__['__use_gnu_getopt']: optlist, unparsed_args = getopt.gnu_getopt(args, shortopts, longopts) else: optlist, unparsed_args = getopt.getopt(args, shortopts, longopts) break except getopt.GetoptError, e: if not e.opt or e.opt in fl: # Not an unrecognized option, reraise the exception as a FlagsError raise FlagsError(e) # Remove offender from args and try again for arg_index in range(len(args)): if ((args[arg_index] == '--' + e.opt) or (args[arg_index] == '-' + e.opt) or (args[arg_index].startswith('--' + e.opt + '='))): unrecognized_opts.append((e.opt, args[arg_index])) args = args[0:arg_index] + args[arg_index+1:] break else: # We should have found the option, so we don't expect to get # here. We could assert, but raising the original exception # might work better. raise FlagsError(e) for name, arg in optlist: if name == '--undefok': flag_names = arg.split(',') undefok_flags.extend(flag_names) # For boolean flags, if --undefok=boolflag is specified, then we should # also accept --noboolflag, in addition to --boolflag. # Since we don't know the type of the undefok'd flag, this will affect # non-boolean flags as well. # NOTE: You shouldn't use --undefok=noboolflag, because then we will # accept --nonoboolflag here. We are choosing not to do the conversion # from noboolflag -> boolflag because of the ambiguity that flag names # can start with 'no'. undefok_flags.extend('no' + name for name in flag_names) continue if name.startswith('--'): # long option name = name[2:] short_option = 0 else: # short option name = name[1:] short_option = 1 if fl.has_key(name): flag = fl[name] if flag.boolean and short_option: arg = 1 flag.Parse(arg) # If there were unrecognized options, raise an exception unless # the options were named via --undefok. for opt, value in unrecognized_opts: if opt not in undefok_flags: raise UnrecognizedFlagError(opt, value) if unparsed_args: if self.__dict__['__use_gnu_getopt']: # if using gnu_getopt just return the program name + remainder of argv. ret_val = argv[:1] + unparsed_args else: # unparsed_args becomes the first non-flag detected by getopt to # the end of argv. Because argv may have been modified above, # return original_argv for this region. ret_val = argv[:1] + original_argv[-len(unparsed_args):] else: ret_val = argv[:1] self._AssertAllValidators() return ret_val def Reset(self): """Resets the values to the point before FLAGS(argv) was called.""" for f in self.FlagDict().values(): f.Unparse() def RegisteredFlags(self): """Returns: a list of the names and short names of all registered flags.""" return self.FlagDict().keys() def FlagValuesDict(self): """Returns: a dictionary that maps flag names to flag values.""" flag_values = {} for flag_name in self.RegisteredFlags(): flag = self.FlagDict()[flag_name] flag_values[flag_name] = flag.value return flag_values def __str__(self): """Generates a help string for all known flags.""" return self.GetHelp() def GetHelp(self, prefix=''): """Generates a help string for all known flags.""" helplist = [] flags_by_module = self.FlagsByModuleDict() if flags_by_module: modules = flags_by_module.keys() modules.sort() # Print the help for the main module first, if possible. main_module = _GetMainModule() if main_module in modules: modules.remove(main_module) modules = [main_module] + modules for module in modules: self.__RenderOurModuleFlags(module, helplist) self.__RenderModuleFlags('gflags', _SPECIAL_FLAGS.FlagDict().values(), helplist) else: # Just print one long list of flags. self.__RenderFlagList( self.FlagDict().values() + _SPECIAL_FLAGS.FlagDict().values(), helplist, prefix) return '\n'.join(helplist) def __RenderModuleFlags(self, module, flags, output_lines, prefix=""): """Generates a help string for a given module.""" if not isinstance(module, str): module = module.__name__ output_lines.append('\n%s%s:' % (prefix, module)) self.__RenderFlagList(flags, output_lines, prefix + " ") def __RenderOurModuleFlags(self, module, output_lines, prefix=""): """Generates a help string for a given module.""" flags = self._GetFlagsDefinedByModule(module) if flags: self.__RenderModuleFlags(module, flags, output_lines, prefix) def __RenderOurModuleKeyFlags(self, module, output_lines, prefix=""): """Generates a help string for the key flags of a given module. Args: module: A module object or a module name (a string). output_lines: A list of strings. The generated help message lines will be appended to this list. prefix: A string that is prepended to each generated help line. """ key_flags = self._GetKeyFlagsForModule(module) if key_flags: self.__RenderModuleFlags(module, key_flags, output_lines, prefix) def ModuleHelp(self, module): """Describe the key flags of a module. Args: module: A module object or a module name (a string). Returns: string describing the key flags of a module. """ helplist = [] self.__RenderOurModuleKeyFlags(module, helplist) return '\n'.join(helplist) def MainModuleHelp(self): """Describe the key flags of the main module. Returns: string describing the key flags of a module. """ return self.ModuleHelp(_GetMainModule()) def __RenderFlagList(self, flaglist, output_lines, prefix=" "): fl = self.FlagDict() special_fl = _SPECIAL_FLAGS.FlagDict() flaglist = [(flag.name, flag) for flag in flaglist] flaglist.sort() flagset = {} for (name, flag) in flaglist: # It's possible this flag got deleted or overridden since being # registered in the per-module flaglist. Check now against the # canonical source of current flag information, the FlagDict. if fl.get(name, None) != flag and special_fl.get(name, None) != flag: # a different flag is using this name now continue # only print help once if flagset.has_key(flag): continue flagset[flag] = 1 flaghelp = "" if flag.short_name: flaghelp += "-%s," % flag.short_name if flag.boolean: flaghelp += "--[no]%s" % flag.name + ":" else: flaghelp += "--%s" % flag.name + ":" flaghelp += " " if flag.help: flaghelp += flag.help flaghelp = TextWrap(flaghelp, indent=prefix+" ", firstline_indent=prefix) if flag.default_as_str: flaghelp += "\n" flaghelp += TextWrap("(default: %s)" % flag.default_as_str, indent=prefix+" ") if flag.parser.syntactic_help: flaghelp += "\n" flaghelp += TextWrap("(%s)" % flag.parser.syntactic_help, indent=prefix+" ") output_lines.append(flaghelp) def get(self, name, default): """Returns the value of a flag (if not None) or a default value. Args: name: A string, the name of a flag. default: Default value to use if the flag value is None. """ value = self.__getattr__(name) if value is not None: # Can't do if not value, b/c value might be '0' or "" return value else: return default def ShortestUniquePrefixes(self, fl): """Returns: dictionary; maps flag names to their shortest unique prefix.""" # Sort the list of flag names sorted_flags = [] for name, flag in fl.items(): sorted_flags.append(name) if flag.boolean: sorted_flags.append('no%s' % name) sorted_flags.sort() # For each name in the sorted list, determine the shortest unique # prefix by comparing itself to the next name and to the previous # name (the latter check uses cached info from the previous loop). shortest_matches = {} prev_idx = 0 for flag_idx in range(len(sorted_flags)): curr = sorted_flags[flag_idx] if flag_idx == (len(sorted_flags) - 1): next = None else: next = sorted_flags[flag_idx+1] next_len = len(next) for curr_idx in range(len(curr)): if (next is None or curr_idx >= next_len or curr[curr_idx] != next[curr_idx]): # curr longer than next or no more chars in common shortest_matches[curr] = curr[:max(prev_idx, curr_idx) + 1] prev_idx = curr_idx break else: # curr shorter than (or equal to) next shortest_matches[curr] = curr prev_idx = curr_idx + 1 # next will need at least one more char return shortest_matches def __IsFlagFileDirective(self, flag_string): """Checks whether flag_string contain a --flagfile=<foo> directive.""" if isinstance(flag_string, type("")): if flag_string.startswith('--flagfile='): return 1 elif flag_string == '--flagfile': return 1 elif flag_string.startswith('-flagfile='): return 1 elif flag_string == '-flagfile': return 1 else: return 0 return 0 def ExtractFilename(self, flagfile_str): """Returns filename from a flagfile_str of form -[-]flagfile=filename. The cases of --flagfile foo and -flagfile foo shouldn't be hitting this function, as they are dealt with in the level above this function. """ if flagfile_str.startswith('--flagfile='): return os.path.expanduser((flagfile_str[(len('--flagfile=')):]).strip()) elif flagfile_str.startswith('-flagfile='): return os.path.expanduser((flagfile_str[(len('-flagfile=')):]).strip()) else: raise FlagsError('Hit illegal --flagfile type: %s' % flagfile_str) def __GetFlagFileLines(self, filename, parsed_file_list): """Returns the useful (!=comments, etc) lines from a file with flags. Args: filename: A string, the name of the flag file. parsed_file_list: A list of the names of the files we have already read. MUTATED BY THIS FUNCTION. Returns: List of strings. See the note below. NOTE(springer): This function checks for a nested --flagfile=<foo> tag and handles the lower file recursively. It returns a list of all the lines that _could_ contain command flags. This is EVERYTHING except whitespace lines and comments (lines starting with '#' or '//'). """ line_list = [] # All line from flagfile. flag_line_list = [] # Subset of lines w/o comments, blanks, flagfile= tags. try: file_obj = open(filename, 'r') except IOError, e_msg: print e_msg print 'ERROR:: Unable to open flagfile: %s' % (filename) return flag_line_list line_list = file_obj.readlines() file_obj.close() parsed_file_list.append(filename) # This is where we check each line in the file we just read. for line in line_list: if line.isspace(): pass # Checks for comment (a line that starts with '#'). elif line.startswith('#') or line.startswith('//'): pass # Checks for a nested "--flagfile=<bar>" flag in the current file. # If we find one, recursively parse down into that file. elif self.__IsFlagFileDirective(line): sub_filename = self.ExtractFilename(line) # We do a little safety check for reparsing a file we've already done. if not sub_filename in parsed_file_list: included_flags = self.__GetFlagFileLines(sub_filename, parsed_file_list) flag_line_list.extend(included_flags) else: # Case of hitting a circularly included file. print >>sys.stderr, ('Warning: Hit circular flagfile dependency: %s' % sub_filename) else: # Any line that's not a comment or a nested flagfile should get # copied into 2nd position. This leaves earlier arguements # further back in the list, thus giving them higher priority. flag_line_list.append(line.strip()) return flag_line_list def ReadFlagsFromFiles(self, argv, force_gnu=True): """Processes command line args, but also allow args to be read from file. Args: argv: A list of strings, usually sys.argv[1:], which may contain one or more flagfile directives of the form --flagfile="./filename". Note that the name of the program (sys.argv[0]) should be omitted. force_gnu: If False, --flagfile parsing obeys normal flag semantics. If True, --flagfile parsing instead follows gnu_getopt semantics. *** WARNING *** force_gnu=False may become the future default! Returns: A new list which has the original list combined with what we read from any flagfile(s). References: Global gflags.FLAG class instance. This function should be called before the normal FLAGS(argv) call. This function scans the input list for a flag that looks like: --flagfile=<somefile>. Then it opens <somefile>, reads all valid key and value pairs and inserts them into the input list between the first item of the list and any subsequent items in the list. Note that your application's flags are still defined the usual way using gflags DEFINE_flag() type functions. Notes (assuming we're getting a commandline of some sort as our input): --> Flags from the command line argv _should_ always take precedence! --> A further "--flagfile=<otherfile.cfg>" CAN be nested in a flagfile. It will be processed after the parent flag file is done. --> For duplicate flags, first one we hit should "win". --> In a flagfile, a line beginning with # or // is a comment. --> Entirely blank lines _should_ be ignored. """ parsed_file_list = [] rest_of_args = argv new_argv = [] while rest_of_args: current_arg = rest_of_args[0] rest_of_args = rest_of_args[1:] if self.__IsFlagFileDirective(current_arg): # This handles the case of -(-)flagfile foo. In this case the # next arg really is part of this one. if current_arg == '--flagfile' or current_arg == '-flagfile': if not rest_of_args: raise IllegalFlagValue('--flagfile with no argument') flag_filename = os.path.expanduser(rest_of_args[0]) rest_of_args = rest_of_args[1:] else: # This handles the case of (-)-flagfile=foo. flag_filename = self.ExtractFilename(current_arg) new_argv[0:0] = self.__GetFlagFileLines(flag_filename, parsed_file_list) else: new_argv.append(current_arg) # Stop parsing after '--', like getopt and gnu_getopt. if current_arg == '--': break # Stop parsing after a non-flag, like getopt. if not current_arg.startswith('-'): if not force_gnu and not self.__dict__['__use_gnu_getopt']: break if rest_of_args: new_argv.extend(rest_of_args) return new_argv def FlagsIntoString(self): """Returns a string with the flags assignments from this FlagValues object. This function ignores flags whose value is None. Each flag assignment is separated by a newline. NOTE: MUST mirror the behavior of the C++ function CommandlineFlagsIntoString from google3/base/commandlineflags.cc. """ s = '' for flag in self.FlagDict().values(): if flag.value is not None: s += flag.Serialize() + '\n' return s def AppendFlagsIntoFile(self, filename): """Appends all flags assignments from this FlagInfo object to a file. Output will be in the format of a flagfile. NOTE: MUST mirror the behavior of the C++ version of AppendFlagsIntoFile from google3/base/commandlineflags.cc. """ out_file = open(filename, 'a') out_file.write(self.FlagsIntoString()) out_file.close() def WriteHelpInXMLFormat(self, outfile=None): """Outputs flag documentation in XML format. NOTE: We use element names that are consistent with those used by the C++ command-line flag library, from google3/base/commandlineflags_reporting.cc. We also use a few new elements (e.g., <key>), but we do not interfere / overlap with existing XML elements used by the C++ library. Please maintain this consistency. Args: outfile: File object we write to. Default None means sys.stdout. """ outfile = outfile or sys.stdout outfile.write('<?xml version=\"1.0\"?>\n') outfile.write('<AllFlags>\n') indent = ' ' _WriteSimpleXMLElement(outfile, 'program', os.path.basename(sys.argv[0]), indent) usage_doc = sys.modules['__main__'].__doc__ if not usage_doc: usage_doc = '\nUSAGE: %s [flags]\n' % sys.argv[0] else: usage_doc = usage_doc.replace('%s', sys.argv[0]) _WriteSimpleXMLElement(outfile, 'usage', usage_doc, indent) # Get list of key flags for the main module. key_flags = self._GetKeyFlagsForModule(_GetMainModule()) # Sort flags by declaring module name and next by flag name. flags_by_module = self.FlagsByModuleDict() all_module_names = list(flags_by_module.keys()) all_module_names.sort() for module_name in all_module_names: flag_list = [(f.name, f) for f in flags_by_module[module_name]] flag_list.sort() for unused_flag_name, flag in flag_list: is_key = flag in key_flags flag.WriteInfoInXMLFormat(outfile, module_name, is_key=is_key, indent=indent) outfile.write('</AllFlags>\n') outfile.flush() def AddValidator(self, validator): """Register new flags validator to be checked. Args: validator: gflags_validators.Validator Raises: AttributeError: if validators work with a non-existing flag. """ for flag_name in validator.GetFlagsNames(): flag = self.FlagDict()[flag_name] flag.validators.append(validator) # end of FlagValues definition # The global FlagValues instance FLAGS = FlagValues() def _MakeXMLSafe(s): """Escapes <, >, and & from s, and removes XML 1.0-illegal chars.""" s = cgi.escape(s) # Escape <, >, and & # Remove characters that cannot appear in an XML 1.0 document # (http://www.w3.org/TR/REC-xml/#charsets). # # NOTE: if there are problems with current solution, one may move to # XML 1.1, which allows such chars, if they're entity-escaped (&#xHH;). s = re.sub(r'[\x00-\x08\x0b\x0c\x0e-\x1f]', '', s) return s def _WriteSimpleXMLElement(outfile, name, value, indent): """Writes a simple XML element. Args: outfile: File object we write the XML element to. name: A string, the name of XML element. value: A Python object, whose string representation will be used as the value of the XML element. indent: A string, prepended to each line of generated output. """ value_str = str(value) if isinstance(value, bool): # Display boolean values as the C++ flag library does: no caps. value_str = value_str.lower() outfile.write('%s<%s>%s</%s>\n' % (indent, name, _MakeXMLSafe(value_str), name)) class Flag: """Information about a command-line flag. 'Flag' objects define the following fields: .name - the name for this flag .default - the default value for this flag .default_as_str - default value as repr'd string, e.g., "'true'" (or None) .value - the most recent parsed value of this flag; set by Parse() .help - a help string or None if no help is available .short_name - the single letter alias for this flag (or None) .boolean - if 'true', this flag does not accept arguments .present - true if this flag was parsed from command line flags. .parser - an ArgumentParser object .serializer - an ArgumentSerializer object .allow_override - the flag may be redefined without raising an error The only public method of a 'Flag' object is Parse(), but it is typically only called by a 'FlagValues' object. The Parse() method is a thin wrapper around the 'ArgumentParser' Parse() method. The parsed value is saved in .value, and the .present attribute is updated. If this flag was already present, a FlagsError is raised. Parse() is also called during __init__ to parse the default value and initialize the .value attribute. This enables other python modules to safely use flags even if the __main__ module neglects to parse the command line arguments. The .present attribute is cleared after __init__ parsing. If the default value is set to None, then the __init__ parsing step is skipped and the .value attribute is initialized to None. Note: The default value is also presented to the user in the help string, so it is important that it be a legal value for this flag. """ def __init__(self, parser, serializer, name, default, help_string, short_name=None, boolean=0, allow_override=0): self.name = name if not help_string: help_string = '(no help available)' self.help = help_string self.short_name = short_name self.boolean = boolean self.present = 0 self.parser = parser self.serializer = serializer self.allow_override = allow_override self.value = None self.validators = [] self.SetDefault(default) def __GetParsedValueAsString(self, value): if value is None: return None if self.serializer: return repr(self.serializer.Serialize(value)) if self.boolean: if value: return repr('true') else: return repr('false') return repr(str(value)) def Parse(self, argument): try: self.value = self.parser.Parse(argument) except ValueError, e: # recast ValueError as IllegalFlagValue raise IllegalFlagValue("flag --%s=%s: %s" % (self.name, argument, e)) self.present += 1 def Unparse(self): if self.default is None: self.value = None else: self.Parse(self.default) self.present = 0 def Serialize(self): if self.value is None: return '' if self.boolean: if self.value: return "--%s" % self.name else: return "--no%s" % self.name else: if not self.serializer: raise FlagsError("Serializer not present for flag %s" % self.name) return "--%s=%s" % (self.name, self.serializer.Serialize(self.value)) def SetDefault(self, value): """Changes the default value (and current value too) for this Flag.""" # We can't allow a None override because it may end up not being # passed to C++ code when we're overriding C++ flags. So we # cowardly bail out until someone fixes the semantics of trying to # pass None to a C++ flag. See swig_flags.Init() for details on # this behavior. # TODO(olexiy): Users can directly call this method, bypassing all flags # validators (we don't have FlagValues here, so we can not check # validators). # The simplest solution I see is to make this method private. # Another approach would be to store reference to the corresponding # FlagValues with each flag, but this seems to be an overkill. if value is None and self.allow_override: raise DuplicateFlagCannotPropagateNoneToSwig(self.name) self.default = value self.Unparse() self.default_as_str = self.__GetParsedValueAsString(self.value) def Type(self): """Returns: a string that describes the type of this Flag.""" # NOTE: we use strings, and not the types.*Type constants because # our flags can have more exotic types, e.g., 'comma separated list # of strings', 'whitespace separated list of strings', etc. return self.parser.Type() def WriteInfoInXMLFormat(self, outfile, module_name, is_key=False, indent=''): """Writes common info about this flag, in XML format. This is information that is relevant to all flags (e.g., name, meaning, etc.). If you defined a flag that has some other pieces of info, then please override _WriteCustomInfoInXMLFormat. Please do NOT override this method. Args: outfile: File object we write to. module_name: A string, the name of the module that defines this flag. is_key: A boolean, True iff this flag is key for main module. indent: A string that is prepended to each generated line. """ outfile.write(indent + '<flag>\n') inner_indent = indent + ' ' if is_key: _WriteSimpleXMLElement(outfile, 'key', 'yes', inner_indent) _WriteSimpleXMLElement(outfile, 'file', module_name, inner_indent) # Print flag features that are relevant for all flags. _WriteSimpleXMLElement(outfile, 'name', self.name, inner_indent) if self.short_name: _WriteSimpleXMLElement(outfile, 'short_name', self.short_name, inner_indent) if self.help: _WriteSimpleXMLElement(outfile, 'meaning', self.help, inner_indent) # The default flag value can either be represented as a string like on the # command line, or as a Python object. We serialize this value in the # latter case in order to remain consistent. if self.serializer and not isinstance(self.default, str): default_serialized = self.serializer.Serialize(self.default) else: default_serialized = self.default _WriteSimpleXMLElement(outfile, 'default', default_serialized, inner_indent) _WriteSimpleXMLElement(outfile, 'current', self.value, inner_indent) _WriteSimpleXMLElement(outfile, 'type', self.Type(), inner_indent) # Print extra flag features this flag may have. self._WriteCustomInfoInXMLFormat(outfile, inner_indent) outfile.write(indent + '</flag>\n') def _WriteCustomInfoInXMLFormat(self, outfile, indent): """Writes extra info about this flag, in XML format. "Extra" means "not already printed by WriteInfoInXMLFormat above." Args: outfile: File object we write to. indent: A string that is prepended to each generated line. """ # Usually, the parser knows the extra details about the flag, so # we just forward the call to it. self.parser.WriteCustomInfoInXMLFormat(outfile, indent) # End of Flag definition class _ArgumentParserCache(type): """Metaclass used to cache and share argument parsers among flags.""" _instances = {} def __call__(mcs, *args, **kwargs): """Returns an instance of the argument parser cls. This method overrides behavior of the __new__ methods in all subclasses of ArgumentParser (inclusive). If an instance for mcs with the same set of arguments exists, this instance is returned, otherwise a new instance is created. If any keyword arguments are defined, or the values in args are not hashable, this method always returns a new instance of cls. Args: args: Positional initializer arguments. kwargs: Initializer keyword arguments. Returns: An instance of cls, shared or new. """ if kwargs: return type.__call__(mcs, *args, **kwargs) else: instances = mcs._instances key = (mcs,) + tuple(args) try: return instances[key] except KeyError: # No cache entry for key exists, create a new one. return instances.setdefault(key, type.__call__(mcs, *args)) except TypeError: # An object in args cannot be hashed, always return # a new instance. return type.__call__(mcs, *args) class ArgumentParser(object): """Base class used to parse and convert arguments. The Parse() method checks to make sure that the string argument is a legal value and convert it to a native type. If the value cannot be converted, it should throw a 'ValueError' exception with a human readable explanation of why the value is illegal. Subclasses should also define a syntactic_help string which may be presented to the user to describe the form of the legal values. Argument parser classes must be stateless, since instances are cached and shared between flags. Initializer arguments are allowed, but all member variables must be derived from initializer arguments only. """ __metaclass__ = _ArgumentParserCache syntactic_help = "" def Parse(self, argument): """Default implementation: always returns its argument unmodified.""" return argument def Type(self): return 'string' def WriteCustomInfoInXMLFormat(self, outfile, indent): pass class ArgumentSerializer: """Base class for generating string representations of a flag value.""" def Serialize(self, value): return str(value) class ListSerializer(ArgumentSerializer): def __init__(self, list_sep): self.list_sep = list_sep def Serialize(self, value): return self.list_sep.join([str(x) for x in value]) # Flags validators def RegisterValidator(flag_name, checker, message='Flag validation failed', flag_values=FLAGS): """Adds a constraint, which will be enforced during program execution. The constraint is validated when flags are initially parsed, and after each change of the corresponding flag's value. Args: flag_name: string, name of the flag to be checked. checker: method to validate the flag. input - value of the corresponding flag (string, boolean, etc. This value will be passed to checker by the library). See file's docstring for examples. output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise gflags_validators.Error(desired_error_message). message: error text to be shown to the user if checker returns False. If checker raises gflags_validators.Error, message from the raised Error will be shown. flag_values: FlagValues Raises: AttributeError: if flag_name is not registered as a valid flag name. """ flag_values.AddValidator(gflags_validators.SimpleValidator(flag_name, checker, message)) def MarkFlagAsRequired(flag_name, flag_values=FLAGS): """Ensure that flag is not None during program execution. Registers a flag validator, which will follow usual validator rules. Args: flag_name: string, name of the flag flag_values: FlagValues Raises: AttributeError: if flag_name is not registered as a valid flag name. """ RegisterValidator(flag_name, lambda value: value is not None, message='Flag --%s must be specified.' % flag_name, flag_values=flag_values) def _RegisterBoundsValidatorIfNeeded(parser, name, flag_values): """Enforce lower and upper bounds for numeric flags. Args: parser: NumericParser (either FloatParser or IntegerParser). Provides lower and upper bounds, and help text to display. name: string, name of the flag flag_values: FlagValues """ if parser.lower_bound is not None or parser.upper_bound is not None: def Checker(value): if value is not None and parser.IsOutsideBounds(value): message = '%s is not %s' % (value, parser.syntactic_help) raise gflags_validators.Error(message) return True RegisterValidator(name, Checker, flag_values=flag_values) # The DEFINE functions are explained in mode details in the module doc string. def DEFINE(parser, name, default, help, flag_values=FLAGS, serializer=None, **args): """Registers a generic Flag object. NOTE: in the docstrings of all DEFINE* functions, "registers" is short for "creates a new flag and registers it". Auxiliary function: clients should use the specialized DEFINE_<type> function instead. Args: parser: ArgumentParser that is used to parse the flag arguments. name: A string, the flag name. default: The default value of the flag. help: A help string. flag_values: FlagValues object the flag will be registered with. serializer: ArgumentSerializer that serializes the flag value. args: Dictionary with extra keyword args that are passes to the Flag __init__. """ DEFINE_flag(Flag(parser, serializer, name, default, help, **args), flag_values) def DEFINE_flag(flag, flag_values=FLAGS): """Registers a 'Flag' object with a 'FlagValues' object. By default, the global FLAGS 'FlagValue' object is used. Typical users will use one of the more specialized DEFINE_xxx functions, such as DEFINE_string or DEFINE_integer. But developers who need to create Flag objects themselves should use this function to register their flags. """ # copying the reference to flag_values prevents pychecker warnings fv = flag_values fv[flag.name] = flag # Tell flag_values who's defining the flag. if isinstance(flag_values, FlagValues): # Regarding the above isinstance test: some users pass funny # values of flag_values (e.g., {}) in order to avoid the flag # registration (in the past, there used to be a flag_values == # FLAGS test here) and redefine flags with the same name (e.g., # debug). To avoid breaking their code, we perform the # registration only if flag_values is a real FlagValues object. flag_values._RegisterFlagByModule(_GetCallingModule(), flag) def _InternalDeclareKeyFlags(flag_names, flag_values=FLAGS, key_flag_values=None): """Declares a flag as key for the calling module. Internal function. User code should call DECLARE_key_flag or ADOPT_module_key_flags instead. Args: flag_names: A list of strings that are names of already-registered Flag objects. flag_values: A FlagValues object that the flags listed in flag_names have registered with (the value of the flag_values argument from the DEFINE_* calls that defined those flags). This should almost never need to be overridden. key_flag_values: A FlagValues object that (among possibly many other things) keeps track of the key flags for each module. Default None means "same as flag_values". This should almost never need to be overridden. Raises: UnrecognizedFlagError: when we refer to a flag that was not defined yet. """ key_flag_values = key_flag_values or flag_values module = _GetCallingModule() for flag_name in flag_names: if flag_name not in flag_values: raise UnrecognizedFlagError(flag_name) flag = flag_values.FlagDict()[flag_name] key_flag_values._RegisterKeyFlagForModule(module, flag) def DECLARE_key_flag(flag_name, flag_values=FLAGS): """Declares one flag as key to the current module. Key flags are flags that are deemed really important for a module. They are important when listing help messages; e.g., if the --helpshort command-line flag is used, then only the key flags of the main module are listed (instead of all flags, as in the case of --help). Sample usage: flags.DECLARED_key_flag('flag_1') Args: flag_name: A string, the name of an already declared flag. (Redeclaring flags as key, including flags implicitly key because they were declared in this module, is a no-op.) flag_values: A FlagValues object. This should almost never need to be overridden. """ if flag_name in _SPECIAL_FLAGS: # Take care of the special flags, e.g., --flagfile, --undefok. # These flags are defined in _SPECIAL_FLAGS, and are treated # specially during flag parsing, taking precedence over the # user-defined flags. _InternalDeclareKeyFlags([flag_name], flag_values=_SPECIAL_FLAGS, key_flag_values=flag_values) return _InternalDeclareKeyFlags([flag_name], flag_values=flag_values) def ADOPT_module_key_flags(module, flag_values=FLAGS): """Declares that all flags key to a module are key to the current module. Args: module: A module object. flag_values: A FlagValues object. This should almost never need to be overridden. Raises: FlagsError: When given an argument that is a module name (a string), instead of a module object. """ # NOTE(salcianu): an even better test would be if not # isinstance(module, types.ModuleType) but I didn't want to import # types for such a tiny use. if isinstance(module, str): raise FlagsError('Received module name %s; expected a module object.' % module) _InternalDeclareKeyFlags( [f.name for f in flag_values._GetKeyFlagsForModule(module.__name__)], flag_values=flag_values) # If module is this flag module, take _SPECIAL_FLAGS into account. if module == _GetThisModuleObjectAndName()[0]: _InternalDeclareKeyFlags( # As we associate flags with _GetCallingModule(), the special # flags defined in this module are incorrectly registered with # a different module. So, we can't use _GetKeyFlagsForModule. # Instead, we take all flags from _SPECIAL_FLAGS (a private # FlagValues, where no other module should register flags). [f.name for f in _SPECIAL_FLAGS.FlagDict().values()], flag_values=_SPECIAL_FLAGS, key_flag_values=flag_values) # # STRING FLAGS # def DEFINE_string(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value can be any string.""" parser = ArgumentParser() serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) # # BOOLEAN FLAGS # # and the special HELP flags. class BooleanParser(ArgumentParser): """Parser of boolean values.""" def Convert(self, argument): """Converts the argument to a boolean; raise ValueError on errors.""" if type(argument) == str: if argument.lower() in ['true', 't', '1']: return True elif argument.lower() in ['false', 'f', '0']: return False bool_argument = bool(argument) if argument == bool_argument: # The argument is a valid boolean (True, False, 0, or 1), and not just # something that always converts to bool (list, string, int, etc.). return bool_argument raise ValueError('Non-boolean argument to boolean flag', argument) def Parse(self, argument): val = self.Convert(argument) return val def Type(self): return 'bool' class BooleanFlag(Flag): """Basic boolean flag. Boolean flags do not take any arguments, and their value is either True (1) or False (0). The false value is specified on the command line by prepending the word 'no' to either the long or the short flag name. For example, if a Boolean flag was created whose long name was 'update' and whose short name was 'x', then this flag could be explicitly unset through either --noupdate or --nox. """ def __init__(self, name, default, help, short_name=None, **args): p = BooleanParser() Flag.__init__(self, p, None, name, default, help, short_name, 1, **args) if not self.help: self.help = "a boolean value" def DEFINE_boolean(name, default, help, flag_values=FLAGS, **args): """Registers a boolean flag. Such a boolean flag does not take an argument. If a user wants to specify a false value explicitly, the long option beginning with 'no' must be used: i.e. --noflag This flag will have a value of None, True or False. None is possible if default=None and the user does not specify the flag on the command line. """ DEFINE_flag(BooleanFlag(name, default, help, **args), flag_values) # Match C++ API to unconfuse C++ people. DEFINE_bool = DEFINE_boolean class HelpFlag(BooleanFlag): """ HelpFlag is a special boolean flag that prints usage information and raises a SystemExit exception if it is ever found in the command line arguments. Note this is called with allow_override=1, so other apps can define their own --help flag, replacing this one, if they want. """ def __init__(self): BooleanFlag.__init__(self, "help", 0, "show this help", short_name="?", allow_override=1) def Parse(self, arg): if arg: doc = sys.modules["__main__"].__doc__ flags = str(FLAGS) print doc or ("\nUSAGE: %s [flags]\n" % sys.argv[0]) if flags: print "flags:" print flags sys.exit(1) class HelpXMLFlag(BooleanFlag): """Similar to HelpFlag, but generates output in XML format.""" def __init__(self): BooleanFlag.__init__(self, 'helpxml', False, 'like --help, but generates XML output', allow_override=1) def Parse(self, arg): if arg: FLAGS.WriteHelpInXMLFormat(sys.stdout) sys.exit(1) class HelpshortFlag(BooleanFlag): """ HelpshortFlag is a special boolean flag that prints usage information for the "main" module, and rasies a SystemExit exception if it is ever found in the command line arguments. Note this is called with allow_override=1, so other apps can define their own --helpshort flag, replacing this one, if they want. """ def __init__(self): BooleanFlag.__init__(self, "helpshort", 0, "show usage only for this module", allow_override=1) def Parse(self, arg): if arg: doc = sys.modules["__main__"].__doc__ flags = FLAGS.MainModuleHelp() print doc or ("\nUSAGE: %s [flags]\n" % sys.argv[0]) if flags: print "flags:" print flags sys.exit(1) # # Numeric parser - base class for Integer and Float parsers # class NumericParser(ArgumentParser): """Parser of numeric values. Parsed value may be bounded to a given upper and lower bound. """ def IsOutsideBounds(self, val): return ((self.lower_bound is not None and val < self.lower_bound) or (self.upper_bound is not None and val > self.upper_bound)) def Parse(self, argument): val = self.Convert(argument) if self.IsOutsideBounds(val): raise ValueError("%s is not %s" % (val, self.syntactic_help)) return val def WriteCustomInfoInXMLFormat(self, outfile, indent): if self.lower_bound is not None: _WriteSimpleXMLElement(outfile, 'lower_bound', self.lower_bound, indent) if self.upper_bound is not None: _WriteSimpleXMLElement(outfile, 'upper_bound', self.upper_bound, indent) def Convert(self, argument): """Default implementation: always returns its argument unmodified.""" return argument # End of Numeric Parser # # FLOAT FLAGS # class FloatParser(NumericParser): """Parser of floating point values. Parsed value may be bounded to a given upper and lower bound. """ number_article = "a" number_name = "number" syntactic_help = " ".join((number_article, number_name)) def __init__(self, lower_bound=None, upper_bound=None): super(FloatParser, self).__init__() self.lower_bound = lower_bound self.upper_bound = upper_bound sh = self.syntactic_help if lower_bound is not None and upper_bound is not None: sh = ("%s in the range [%s, %s]" % (sh, lower_bound, upper_bound)) elif lower_bound == 0: sh = "a non-negative %s" % self.number_name elif upper_bound == 0: sh = "a non-positive %s" % self.number_name elif upper_bound is not None: sh = "%s <= %s" % (self.number_name, upper_bound) elif lower_bound is not None: sh = "%s >= %s" % (self.number_name, lower_bound) self.syntactic_help = sh def Convert(self, argument): """Converts argument to a float; raises ValueError on errors.""" return float(argument) def Type(self): return 'float' # End of FloatParser def DEFINE_float(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value must be a float. If lower_bound or upper_bound are set, then this flag must be within the given range. """ parser = FloatParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) _RegisterBoundsValidatorIfNeeded(parser, name, flag_values=flag_values) # # INTEGER FLAGS # class IntegerParser(NumericParser): """Parser of an integer value. Parsed value may be bounded to a given upper and lower bound. """ number_article = "an" number_name = "integer" syntactic_help = " ".join((number_article, number_name)) def __init__(self, lower_bound=None, upper_bound=None): super(IntegerParser, self).__init__() self.lower_bound = lower_bound self.upper_bound = upper_bound sh = self.syntactic_help if lower_bound is not None and upper_bound is not None: sh = ("%s in the range [%s, %s]" % (sh, lower_bound, upper_bound)) elif lower_bound == 1: sh = "a positive %s" % self.number_name elif upper_bound == -1: sh = "a negative %s" % self.number_name elif lower_bound == 0: sh = "a non-negative %s" % self.number_name elif upper_bound == 0: sh = "a non-positive %s" % self.number_name elif upper_bound is not None: sh = "%s <= %s" % (self.number_name, upper_bound) elif lower_bound is not None: sh = "%s >= %s" % (self.number_name, lower_bound) self.syntactic_help = sh def Convert(self, argument): __pychecker__ = 'no-returnvalues' if type(argument) == str: base = 10 if len(argument) > 2 and argument[0] == "0" and argument[1] == "x": base = 16 try: return int(argument, base) # ValueError is thrown when argument is a string, and overflows an int. except ValueError: return long(argument, base) else: try: return int(argument) # OverflowError is thrown when argument is numeric, and overflows an int. except OverflowError: return long(argument) def Type(self): return 'int' def DEFINE_integer(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value must be an integer. If lower_bound, or upper_bound are set, then this flag must be within the given range. """ parser = IntegerParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) _RegisterBoundsValidatorIfNeeded(parser, name, flag_values=flag_values) # # ENUM FLAGS # class EnumParser(ArgumentParser): """Parser of a string enum value (a string value from a given set). If enum_values (see below) is not specified, any string is allowed. """ def __init__(self, enum_values=None): super(EnumParser, self).__init__() self.enum_values = enum_values def Parse(self, argument): if self.enum_values and argument not in self.enum_values: raise ValueError("value should be one of <%s>" % "|".join(self.enum_values)) return argument def Type(self): return 'string enum' class EnumFlag(Flag): """Basic enum flag; its value can be any string from list of enum_values.""" def __init__(self, name, default, help, enum_values=None, short_name=None, **args): enum_values = enum_values or [] p = EnumParser(enum_values) g = ArgumentSerializer() Flag.__init__(self, p, g, name, default, help, short_name, **args) if not self.help: self.help = "an enum string" self.help = "<%s>: %s" % ("|".join(enum_values), self.help) def _WriteCustomInfoInXMLFormat(self, outfile, indent): for enum_value in self.parser.enum_values: _WriteSimpleXMLElement(outfile, 'enum_value', enum_value, indent) def DEFINE_enum(name, default, enum_values, help, flag_values=FLAGS, **args): """Registers a flag whose value can be any string from enum_values.""" DEFINE_flag(EnumFlag(name, default, help, enum_values, ** args), flag_values) # # LIST FLAGS # class BaseListParser(ArgumentParser): """Base class for a parser of lists of strings. To extend, inherit from this class; from the subclass __init__, call BaseListParser.__init__(self, token, name) where token is a character used to tokenize, and name is a description of the separator. """ def __init__(self, token=None, name=None): assert name super(BaseListParser, self).__init__() self._token = token self._name = name self.syntactic_help = "a %s separated list" % self._name def Parse(self, argument): if isinstance(argument, list): return argument elif argument == '': return [] else: return [s.strip() for s in argument.split(self._token)] def Type(self): return '%s separated list of strings' % self._name class ListParser(BaseListParser): """Parser for a comma-separated list of strings.""" def __init__(self): BaseListParser.__init__(self, ',', 'comma') def WriteCustomInfoInXMLFormat(self, outfile, indent): BaseListParser.WriteCustomInfoInXMLFormat(self, outfile, indent) _WriteSimpleXMLElement(outfile, 'list_separator', repr(','), indent) class WhitespaceSeparatedListParser(BaseListParser): """Parser for a whitespace-separated list of strings.""" def __init__(self): BaseListParser.__init__(self, None, 'whitespace') def WriteCustomInfoInXMLFormat(self, outfile, indent): BaseListParser.WriteCustomInfoInXMLFormat(self, outfile, indent) separators = list(string.whitespace) separators.sort() for ws_char in string.whitespace: _WriteSimpleXMLElement(outfile, 'list_separator', repr(ws_char), indent) def DEFINE_list(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value is a comma-separated list of strings.""" parser = ListParser() serializer = ListSerializer(',') DEFINE(parser, name, default, help, flag_values, serializer, **args) def DEFINE_spaceseplist(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value is a whitespace-separated list of strings. Any whitespace can be used as a separator. """ parser = WhitespaceSeparatedListParser() serializer = ListSerializer(' ') DEFINE(parser, name, default, help, flag_values, serializer, **args) # # MULTI FLAGS # class MultiFlag(Flag): """A flag that can appear multiple time on the command-line. The value of such a flag is a list that contains the individual values from all the appearances of that flag on the command-line. See the __doc__ for Flag for most behavior of this class. Only differences in behavior are described here: * The default value may be either a single value or a list of values. A single value is interpreted as the [value] singleton list. * The value of the flag is always a list, even if the option was only supplied once, and even if the default value is a single value """ def __init__(self, *args, **kwargs): Flag.__init__(self, *args, **kwargs) self.help += ';\n repeat this option to specify a list of values' def Parse(self, arguments): """Parses one or more arguments with the installed parser. Args: arguments: a single argument or a list of arguments (typically a list of default values); a single argument is converted internally into a list containing one item. """ if not isinstance(arguments, list): # Default value may be a list of values. Most other arguments # will not be, so convert them into a single-item list to make # processing simpler below. arguments = [arguments] if self.present: # keep a backup reference to list of previously supplied option values values = self.value else: # "erase" the defaults with an empty list values = [] for item in arguments: # have Flag superclass parse argument, overwriting self.value reference Flag.Parse(self, item) # also increments self.present values.append(self.value) # put list of option values back in the 'value' attribute self.value = values def Serialize(self): if not self.serializer: raise FlagsError("Serializer not present for flag %s" % self.name) if self.value is None: return '' s = '' multi_value = self.value for self.value in multi_value: if s: s += ' ' s += Flag.Serialize(self) self.value = multi_value return s def Type(self): return 'multi ' + self.parser.Type() def DEFINE_multi(parser, serializer, name, default, help, flag_values=FLAGS, **args): """Registers a generic MultiFlag that parses its args with a given parser. Auxiliary function. Normal users should NOT use it directly. Developers who need to create their own 'Parser' classes for options which can appear multiple times can call this module function to register their flags. """ DEFINE_flag(MultiFlag(parser, serializer, name, default, help, **args), flag_values) def DEFINE_multistring(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value can be a list of any strings. Use the flag on the command line multiple times to place multiple string values into the list. The 'default' may be a single string (which will be converted into a single-element list) or a list of strings. """ parser = ArgumentParser() serializer = ArgumentSerializer() DEFINE_multi(parser, serializer, name, default, help, flag_values, **args) def DEFINE_multi_int(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value can be a list of arbitrary integers. Use the flag on the command line multiple times to place multiple integer values into the list. The 'default' may be a single integer (which will be converted into a single-element list) or a list of integers. """ parser = IntegerParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE_multi(parser, serializer, name, default, help, flag_values, **args) # Now register the flags that we want to exist in all applications. # These are all defined with allow_override=1, so user-apps can use # these flagnames for their own purposes, if they want. DEFINE_flag(HelpFlag()) DEFINE_flag(HelpshortFlag()) DEFINE_flag(HelpXMLFlag()) # Define special flags here so that help may be generated for them. # NOTE: Please do NOT use _SPECIAL_FLAGS from outside this module. _SPECIAL_FLAGS = FlagValues() DEFINE_string( 'flagfile', "", "Insert flag definitions from the given file into the command line.", _SPECIAL_FLAGS) DEFINE_string( 'undefok', "", "comma-separated list of flag names that it is okay to specify " "on the command line even if the program does not define a flag " "with that name. IMPORTANT: flags in this list that have " "arguments MUST use the --flag=value format.", _SPECIAL_FLAGS)
Python
#!/usr/bin/env python # Copyright (c) 2010, Google Inc. # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. """Module to enforce different constraints on flags. A validator represents an invariant, enforced over a one or more flags. See 'FLAGS VALIDATORS' in flags.py's docstring for a usage manual. """ __author__ = 'olexiy@google.com (Olexiy Oryeshko)' class Error(Exception): """Thrown If validator constraint is not satisfied.""" class Validator(object): """Base class for flags validators. Users should NOT overload these classes, and use flags.Register... methods instead. """ # Used to assign each validator an unique insertion_index validators_count = 0 def __init__(self, checker, message): """Constructor to create all validators. Args: checker: function to verify the constraint. Input of this method varies, see SimpleValidator and DictionaryValidator for a detailed description. message: string, error message to be shown to the user """ self.checker = checker self.message = message Validator.validators_count += 1 # Used to assert validators in the order they were registered (CL/18694236) self.insertion_index = Validator.validators_count def Verify(self, flag_values): """Verify that constraint is satisfied. flags library calls this method to verify Validator's constraint. Args: flag_values: flags.FlagValues, containing all flags Raises: Error: if constraint is not satisfied. """ param = self._GetInputToCheckerFunction(flag_values) if not self.checker(param): raise Error(self.message) def GetFlagsNames(self): """Return the names of the flags checked by this validator. Returns: [string], names of the flags """ raise NotImplementedError('This method should be overloaded') def PrintFlagsWithValues(self, flag_values): raise NotImplementedError('This method should be overloaded') def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues, containing all flags. Returns: Return type depends on the specific validator. """ raise NotImplementedError('This method should be overloaded') class SimpleValidator(Validator): """Validator behind RegisterValidator() method. Validates that a single flag passes its checker function. The checker function takes the flag value and returns True (if value looks fine) or, if flag value is not valid, either returns False or raises an Exception.""" def __init__(self, flag_name, checker, message): """Constructor. Args: flag_name: string, name of the flag. checker: function to verify the validator. input - value of the corresponding flag (string, boolean, etc). output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise Error. message: string, error message to be shown to the user if validator's condition is not satisfied """ super(SimpleValidator, self).__init__(checker, message) self.flag_name = flag_name def GetFlagsNames(self): return [self.flag_name] def PrintFlagsWithValues(self, flag_values): return 'flag --%s=%s' % (self.flag_name, flag_values[self.flag_name].value) def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues Returns: value of the corresponding flag. """ return flag_values[self.flag_name].value class DictionaryValidator(Validator): """Validator behind RegisterDictionaryValidator method. Validates that flag values pass their common checker function. The checker function takes flag values and returns True (if values look fine) or, if values are not valid, either returns False or raises an Exception. """ def __init__(self, flag_names, checker, message): """Constructor. Args: flag_names: [string], containing names of the flags used by checker. checker: function to verify the validator. input - dictionary, with keys() being flag_names, and value for each key being the value of the corresponding flag (string, boolean, etc). output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise Error. message: string, error message to be shown to the user if validator's condition is not satisfied """ super(DictionaryValidator, self).__init__(checker, message) self.flag_names = flag_names def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues Returns: dictionary, with keys() being self.lag_names, and value for each key being the value of the corresponding flag (string, boolean, etc). """ return dict([key, flag_values[key].value] for key in self.flag_names) def PrintFlagsWithValues(self, flag_values): prefix = 'flags ' flags_with_values = [] for key in self.flag_names: flags_with_values.append('%s=%s' % (key, flag_values[key].value)) return prefix + ', '.join(flags_with_values) def GetFlagsNames(self): return self.flag_names
Python
#!/usr/bin/env python # Copyright (c) 2007, Google Inc. # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. # # --- # Author: Chad Lester # Design and style contributions by: # Amit Patel, Bogdan Cocosel, Daniel Dulitz, Eric Tiedemann, # Eric Veach, Laurence Gonsalves, Matthew Springer # Code reorganized a bit by Craig Silverstein """This module is used to define and parse command line flags. This module defines a *distributed* flag-definition policy: rather than an application having to define all flags in or near main(), each python module defines flags that are useful to it. When one python module imports another, it gains access to the other's flags. (This is implemented by having all modules share a common, global registry object containing all the flag information.) Flags are defined through the use of one of the DEFINE_xxx functions. The specific function used determines how the flag is parsed, checked, and optionally type-converted, when it's seen on the command line. IMPLEMENTATION: DEFINE_* creates a 'Flag' object and registers it with a 'FlagValues' object (typically the global FlagValues FLAGS, defined here). The 'FlagValues' object can scan the command line arguments and pass flag arguments to the corresponding 'Flag' objects for value-checking and type conversion. The converted flag values are available as attributes of the 'FlagValues' object. Code can access the flag through a FlagValues object, for instance gflags.FLAGS.myflag. Typically, the __main__ module passes the command line arguments to gflags.FLAGS for parsing. At bottom, this module calls getopt(), so getopt functionality is supported, including short- and long-style flags, and the use of -- to terminate flags. Methods defined by the flag module will throw 'FlagsError' exceptions. The exception argument will be a human-readable string. FLAG TYPES: This is a list of the DEFINE_*'s that you can do. All flags take a name, default value, help-string, and optional 'short' name (one-letter name). Some flags have other arguments, which are described with the flag. DEFINE_string: takes any input, and interprets it as a string. DEFINE_bool or DEFINE_boolean: typically does not take an argument: say --myflag to set FLAGS.myflag to true, or --nomyflag to set FLAGS.myflag to false. Alternately, you can say --myflag=true or --myflag=t or --myflag=1 or --myflag=false or --myflag=f or --myflag=0 DEFINE_float: takes an input and interprets it as a floating point number. Takes optional args lower_bound and upper_bound; if the number specified on the command line is out of range, it will raise a FlagError. DEFINE_integer: takes an input and interprets it as an integer. Takes optional args lower_bound and upper_bound as for floats. DEFINE_enum: takes a list of strings which represents legal values. If the command-line value is not in this list, raise a flag error. Otherwise, assign to FLAGS.flag as a string. DEFINE_list: Takes a comma-separated list of strings on the commandline. Stores them in a python list object. DEFINE_spaceseplist: Takes a space-separated list of strings on the commandline. Stores them in a python list object. Example: --myspacesepflag "foo bar baz" DEFINE_multistring: The same as DEFINE_string, except the flag can be specified more than once on the commandline. The result is a python list object (list of strings), even if the flag is only on the command line once. DEFINE_multi_int: The same as DEFINE_integer, except the flag can be specified more than once on the commandline. The result is a python list object (list of ints), even if the flag is only on the command line once. SPECIAL FLAGS: There are a few flags that have special meaning: --help prints a list of all the flags in a human-readable fashion --helpshort prints a list of all key flags (see below). --helpxml prints a list of all flags, in XML format. DO NOT parse the output of --help and --helpshort. Instead, parse the output of --helpxml. For more info, see "OUTPUT FOR --helpxml" below. --flagfile=foo read flags from file foo. --undefok=f1,f2 ignore unrecognized option errors for f1,f2. For boolean flags, you should use --undefok=boolflag, and --boolflag and --noboolflag will be accepted. Do not use --undefok=noboolflag. -- as in getopt(), terminates flag-processing FLAGS VALIDATORS: If your program: - requires flag X to be specified - needs flag Y to match a regular expression - or requires any more general constraint to be satisfied then validators are for you! Each validator represents a constraint over one flag, which is enforced starting from the initial parsing of the flags and until the program terminates. Also, lower_bound and upper_bound for numerical flags are enforced using flag validators. Howto: If you want to enforce a constraint over one flag, use flags.RegisterValidator(flag_name, checker, message='Flag validation failed', flag_values=FLAGS) After flag values are initially parsed, and after any change to the specified flag, method checker(flag_value) will be executed. If constraint is not satisfied, an IllegalFlagValue exception will be raised. See RegisterValidator's docstring for a detailed explanation on how to construct your own checker. EXAMPLE USAGE: FLAGS = flags.FLAGS flags.DEFINE_integer('my_version', 0, 'Version number.') flags.DEFINE_string('filename', None, 'Input file name', short_name='f') flags.RegisterValidator('my_version', lambda value: value % 2 == 0, message='--my_version must be divisible by 2') flags.MarkFlagAsRequired('filename') NOTE ON --flagfile: Flags may be loaded from text files in addition to being specified on the commandline. Any flags you don't feel like typing, throw them in a file, one flag per line, for instance: --myflag=myvalue --nomyboolean_flag You then specify your file with the special flag '--flagfile=somefile'. You CAN recursively nest flagfile= tokens OR use multiple files on the command line. Lines beginning with a single hash '#' or a double slash '//' are comments in your flagfile. Any flagfile=<file> will be interpreted as having a relative path from the current working directory rather than from the place the file was included from: myPythonScript.py --flagfile=config/somefile.cfg If somefile.cfg includes further --flagfile= directives, these will be referenced relative to the original CWD, not from the directory the including flagfile was found in! The caveat applies to people who are including a series of nested files in a different dir than they are executing out of. Relative path names are always from CWD, not from the directory of the parent include flagfile. We do now support '~' expanded directory names. Absolute path names ALWAYS work! EXAMPLE USAGE: import gflags FLAGS = gflags.FLAGS # Flag names are globally defined! So in general, we need to be # careful to pick names that are unlikely to be used by other libraries. # If there is a conflict, we'll get an error at import time. gflags.DEFINE_string('name', 'Mr. President', 'your name') gflags.DEFINE_integer('age', None, 'your age in years', lower_bound=0) gflags.DEFINE_boolean('debug', False, 'produces debugging output') gflags.DEFINE_enum('gender', 'male', ['male', 'female'], 'your gender') def main(argv): try: argv = FLAGS(argv) # parse flags except gflags.FlagsError, e: print '%s\\nUsage: %s ARGS\\n%s' % (e, sys.argv[0], FLAGS) sys.exit(1) if FLAGS.debug: print 'non-flag arguments:', argv print 'Happy Birthday', FLAGS.name if FLAGS.age is not None: print 'You are a %s, who is %d years old' % (FLAGS.gender, FLAGS.age) if __name__ == '__main__': main(sys.argv) KEY FLAGS: As we already explained, each module gains access to all flags defined by all the other modules it transitively imports. In the case of non-trivial scripts, this means a lot of flags ... For documentation purposes, it is good to identify the flags that are key (i.e., really important) to a module. Clearly, the concept of "key flag" is a subjective one. When trying to determine whether a flag is key to a module or not, assume that you are trying to explain your module to a potential user: which flags would you really like to mention first? We'll describe shortly how to declare which flags are key to a module. For the moment, assume we know the set of key flags for each module. Then, if you use the app.py module, you can use the --helpshort flag to print only the help for the flags that are key to the main module, in a human-readable format. NOTE: If you need to parse the flag help, do NOT use the output of --help / --helpshort. That output is meant for human consumption, and may be changed in the future. Instead, use --helpxml; flags that are key for the main module are marked there with a <key>yes</key> element. The set of key flags for a module M is composed of: 1. Flags defined by module M by calling a DEFINE_* function. 2. Flags that module M explictly declares as key by using the function DECLARE_key_flag(<flag_name>) 3. Key flags of other modules that M specifies by using the function ADOPT_module_key_flags(<other_module>) This is a "bulk" declaration of key flags: each flag that is key for <other_module> becomes key for the current module too. Notice that if you do not use the functions described at points 2 and 3 above, then --helpshort prints information only about the flags defined by the main module of our script. In many cases, this behavior is good enough. But if you move part of the main module code (together with the related flags) into a different module, then it is nice to use DECLARE_key_flag / ADOPT_module_key_flags and make sure --helpshort lists all relevant flags (otherwise, your code refactoring may confuse your users). Note: each of DECLARE_key_flag / ADOPT_module_key_flags has its own pluses and minuses: DECLARE_key_flag is more targeted and may lead a more focused --helpshort documentation. ADOPT_module_key_flags is good for cases when an entire module is considered key to the current script. Also, it does not require updates to client scripts when a new flag is added to the module. EXAMPLE USAGE 2 (WITH KEY FLAGS): Consider an application that contains the following three files (two auxiliary modules and a main module): File libfoo.py: import gflags gflags.DEFINE_integer('num_replicas', 3, 'Number of replicas to start') gflags.DEFINE_boolean('rpc2', True, 'Turn on the usage of RPC2.') ... some code ... File libbar.py: import gflags gflags.DEFINE_string('bar_gfs_path', '/gfs/path', 'Path to the GFS files for libbar.') gflags.DEFINE_string('email_for_bar_errors', 'bar-team@google.com', 'Email address for bug reports about module libbar.') gflags.DEFINE_boolean('bar_risky_hack', False, 'Turn on an experimental and buggy optimization.') ... some code ... File myscript.py: import gflags import libfoo import libbar gflags.DEFINE_integer('num_iterations', 0, 'Number of iterations.') # Declare that all flags that are key for libfoo are # key for this module too. gflags.ADOPT_module_key_flags(libfoo) # Declare that the flag --bar_gfs_path (defined in libbar) is key # for this module. gflags.DECLARE_key_flag('bar_gfs_path') ... some code ... When myscript is invoked with the flag --helpshort, the resulted help message lists information about all the key flags for myscript: --num_iterations, --num_replicas, --rpc2, and --bar_gfs_path (in addition to the special flags --help and --helpshort). Of course, myscript uses all the flags declared by it (in this case, just --num_replicas) or by any of the modules it transitively imports (e.g., the modules libfoo, libbar). E.g., it can access the value of FLAGS.bar_risky_hack, even if --bar_risky_hack is not declared as a key flag for myscript. OUTPUT FOR --helpxml: The --helpxml flag generates output with the following structure: <?xml version="1.0"?> <AllFlags> <program>PROGRAM_BASENAME</program> <usage>MAIN_MODULE_DOCSTRING</usage> (<flag> [<key>yes</key>] <file>DECLARING_MODULE</file> <name>FLAG_NAME</name> <meaning>FLAG_HELP_MESSAGE</meaning> <default>DEFAULT_FLAG_VALUE</default> <current>CURRENT_FLAG_VALUE</current> <type>FLAG_TYPE</type> [OPTIONAL_ELEMENTS] </flag>)* </AllFlags> Notes: 1. The output is intentionally similar to the output generated by the C++ command-line flag library. The few differences are due to the Python flags that do not have a C++ equivalent (at least not yet), e.g., DEFINE_list. 2. New XML elements may be added in the future. 3. DEFAULT_FLAG_VALUE is in serialized form, i.e., the string you can pass for this flag on the command-line. E.g., for a flag defined using DEFINE_list, this field may be foo,bar, not ['foo', 'bar']. 4. CURRENT_FLAG_VALUE is produced using str(). This means that the string 'false' will be represented in the same way as the boolean False. Using repr() would have removed this ambiguity and simplified parsing, but would have broken the compatibility with the C++ command-line flags. 5. OPTIONAL_ELEMENTS describe elements relevant for certain kinds of flags: lower_bound, upper_bound (for flags that specify bounds), enum_value (for enum flags), list_separator (for flags that consist of a list of values, separated by a special token). 6. We do not provide any example here: please use --helpxml instead. """ import cgi import getopt import os import re import string import sys import gflags_validators # Are we running at least python 2.2? try: if tuple(sys.version_info[:3]) < (2,2,0): raise NotImplementedError("requires python 2.2.0 or later") except AttributeError: # a very old python, that lacks sys.version_info raise NotImplementedError("requires python 2.2.0 or later") # If we're not running at least python 2.2.1, define True, False, and bool. # Thanks, Guido, for the code. try: True, False, bool except NameError: False = 0 True = 1 def bool(x): if x: return True else: return False # Are we running under pychecker? _RUNNING_PYCHECKER = 'pychecker.python' in sys.modules def _GetCallingModule(): """Returns the name of the module that's calling into this module. We generally use this function to get the name of the module calling a DEFINE_foo... function. """ # Walk down the stack to find the first globals dict that's not ours. for depth in range(1, sys.getrecursionlimit()): if not sys._getframe(depth).f_globals is globals(): globals_for_frame = sys._getframe(depth).f_globals module_name = _GetModuleObjectAndName(globals_for_frame)[1] if module_name is not None: return module_name raise AssertionError("No module was found") def _GetThisModuleObjectAndName(): """Returns: (module object, module name) for this module.""" return _GetModuleObjectAndName(globals()) # module exceptions: class FlagsError(Exception): """The base class for all flags errors.""" pass class DuplicateFlag(FlagsError): """Raised if there is a flag naming conflict.""" pass class DuplicateFlagCannotPropagateNoneToSwig(DuplicateFlag): """Special case of DuplicateFlag -- SWIG flag value can't be set to None. This can be raised when a duplicate flag is created. Even if allow_override is True, we still abort if the new value is None, because it's currently impossible to pass None default value back to SWIG. See FlagValues.SetDefault for details. """ pass # A DuplicateFlagError conveys more information than a # DuplicateFlag. Since there are external modules that create # DuplicateFlags, the interface to DuplicateFlag shouldn't change. class DuplicateFlagError(DuplicateFlag): def __init__(self, flagname, flag_values): self.flagname = flagname message = "The flag '%s' is defined twice." % self.flagname flags_by_module = flag_values.FlagsByModuleDict() for module in flags_by_module: for flag in flags_by_module[module]: if flag.name == flagname or flag.short_name == flagname: message = message + " First from " + module + "," break message = message + " Second from " + _GetCallingModule() DuplicateFlag.__init__(self, message) class IllegalFlagValue(FlagsError): """The flag command line argument is illegal.""" pass class UnrecognizedFlag(FlagsError): """Raised if a flag is unrecognized.""" pass # An UnrecognizedFlagError conveys more information than an UnrecognizedFlag. # Since there are external modules that create DuplicateFlags, the interface to # DuplicateFlag shouldn't change. The flagvalue will be assigned the full value # of the flag and its argument, if any, allowing handling of unrecognzed flags # in an exception handler. # If flagvalue is the empty string, then this exception is an due to a # reference to a flag that was not already defined. class UnrecognizedFlagError(UnrecognizedFlag): def __init__(self, flagname, flagvalue=''): self.flagname = flagname self.flagvalue = flagvalue UnrecognizedFlag.__init__( self, "Unknown command line flag '%s'" % flagname) # Global variable used by expvar _exported_flags = {} _help_width = 80 # width of help output def GetHelpWidth(): """Returns: an integer, the width of help lines that is used in TextWrap.""" return _help_width def CutCommonSpacePrefix(text): """Removes a common space prefix from the lines of a multiline text. If the first line does not start with a space, it is left as it is and only in the remaining lines a common space prefix is being searched for. That means the first line will stay untouched. This is especially useful to turn doc strings into help texts. This is because some people prefer to have the doc comment start already after the apostrophy and then align the following lines while others have the apostrophies on a seperately line. The function also drops trailing empty lines and ignores empty lines following the initial content line while calculating the initial common whitespace. Args: text: text to work on Returns: the resulting text """ text_lines = text.splitlines() # Drop trailing empty lines while text_lines and not text_lines[-1]: text_lines = text_lines[:-1] if text_lines: # We got some content, is the first line starting with a space? if text_lines[0] and text_lines[0][0].isspace(): text_first_line = [] else: text_first_line = [text_lines.pop(0)] # Calculate length of common leading whitesppace (only over content lines) common_prefix = os.path.commonprefix([line for line in text_lines if line]) space_prefix_len = len(common_prefix) - len(common_prefix.lstrip()) # If we have a common space prefix, drop it from all lines if space_prefix_len: for index in xrange(len(text_lines)): if text_lines[index]: text_lines[index] = text_lines[index][space_prefix_len:] return '\n'.join(text_first_line + text_lines) return '' def TextWrap(text, length=None, indent='', firstline_indent=None, tabs=' '): """Wraps a given text to a maximum line length and returns it. We turn lines that only contain whitespaces into empty lines. We keep new lines and tabs (e.g., we do not treat tabs as spaces). Args: text: text to wrap length: maximum length of a line, includes indentation if this is None then use GetHelpWidth() indent: indent for all but first line firstline_indent: indent for first line; if None, fall back to indent tabs: replacement for tabs Returns: wrapped text Raises: FlagsError: if indent not shorter than length FlagsError: if firstline_indent not shorter than length """ # Get defaults where callee used None if length is None: length = GetHelpWidth() if indent is None: indent = '' if len(indent) >= length: raise FlagsError('Indent must be shorter than length') # In line we will be holding the current line which is to be started # with indent (or firstline_indent if available) and then appended # with words. if firstline_indent is None: firstline_indent = '' line = indent else: line = firstline_indent if len(firstline_indent) >= length: raise FlagsError('First iline indent must be shorter than length') # If the callee does not care about tabs we simply convert them to # spaces If callee wanted tabs to be single space then we do that # already here. if not tabs or tabs == ' ': text = text.replace('\t', ' ') else: tabs_are_whitespace = not tabs.strip() line_regex = re.compile('([ ]*)(\t*)([^ \t]+)', re.MULTILINE) # Split the text into lines and the lines with the regex above. The # resulting lines are collected in result[]. For each split we get the # spaces, the tabs and the next non white space (e.g. next word). result = [] for text_line in text.splitlines(): # Store result length so we can find out whether processing the next # line gave any new content old_result_len = len(result) # Process next line with line_regex. For optimization we do an rstrip(). # - process tabs (changes either line or word, see below) # - process word (first try to squeeze on line, then wrap or force wrap) # Spaces found on the line are ignored, they get added while wrapping as # needed. for spaces, current_tabs, word in line_regex.findall(text_line.rstrip()): # If tabs weren't converted to spaces, handle them now if current_tabs: # If the last thing we added was a space anyway then drop # it. But let's not get rid of the indentation. if (((result and line != indent) or (not result and line != firstline_indent)) and line[-1] == ' '): line = line[:-1] # Add the tabs, if that means adding whitespace, just add it at # the line, the rstrip() code while shorten the line down if # necessary if tabs_are_whitespace: line += tabs * len(current_tabs) else: # if not all tab replacement is whitespace we prepend it to the word word = tabs * len(current_tabs) + word # Handle the case where word cannot be squeezed onto current last line if len(line) + len(word) > length and len(indent) + len(word) <= length: result.append(line.rstrip()) line = indent + word word = '' # No space left on line or can we append a space? if len(line) + 1 >= length: result.append(line.rstrip()) line = indent else: line += ' ' # Add word and shorten it up to allowed line length. Restart next # line with indent and repeat, or add a space if we're done (word # finished) This deals with words that caanot fit on one line # (e.g. indent + word longer than allowed line length). while len(line) + len(word) >= length: line += word result.append(line[:length]) word = line[length:] line = indent # Default case, simply append the word and a space if word: line += word + ' ' # End of input line. If we have content we finish the line. If the # current line is just the indent but we had content in during this # original line then we need to add an emoty line. if (result and line != indent) or (not result and line != firstline_indent): result.append(line.rstrip()) elif len(result) == old_result_len: result.append('') line = indent return '\n'.join(result) def DocToHelp(doc): """Takes a __doc__ string and reformats it as help.""" # Get rid of starting and ending white space. Using lstrip() or even # strip() could drop more than maximum of first line and right space # of last line. doc = doc.strip() # Get rid of all empty lines whitespace_only_line = re.compile('^[ \t]+$', re.M) doc = whitespace_only_line.sub('', doc) # Cut out common space at line beginnings doc = CutCommonSpacePrefix(doc) # Just like this module's comment, comments tend to be aligned somehow. # In other words they all start with the same amount of white space # 1) keep double new lines # 2) keep ws after new lines if not empty line # 3) all other new lines shall be changed to a space # Solution: Match new lines between non white space and replace with space. doc = re.sub('(?<=\S)\n(?=\S)', ' ', doc, re.M) return doc def _GetModuleObjectAndName(globals_dict): """Returns the module that defines a global environment, and its name. Args: globals_dict: A dictionary that should correspond to an environment providing the values of the globals. Returns: A pair consisting of (1) module object and (2) module name (a string). Returns (None, None) if the module could not be identified. """ # The use of .items() (instead of .iteritems()) is NOT a mistake: if # a parallel thread imports a module while we iterate over # .iteritems() (not nice, but possible), we get a RuntimeError ... # Hence, we use the slightly slower but safer .items(). for name, module in sys.modules.items(): if getattr(module, '__dict__', None) is globals_dict: if name == '__main__': # Pick a more informative name for the main module. name = sys.argv[0] return (module, name) return (None, None) def _GetMainModule(): """Returns the name of the module from which execution started.""" for depth in range(1, sys.getrecursionlimit()): try: globals_of_main = sys._getframe(depth).f_globals except ValueError: return _GetModuleObjectAndName(globals_of_main)[1] raise AssertionError("No module was found") class FlagValues: """Registry of 'Flag' objects. A 'FlagValues' can then scan command line arguments, passing flag arguments through to the 'Flag' objects that it owns. It also provides easy access to the flag values. Typically only one 'FlagValues' object is needed by an application: gflags.FLAGS This class is heavily overloaded: 'Flag' objects are registered via __setitem__: FLAGS['longname'] = x # register a new flag The .value attribute of the registered 'Flag' objects can be accessed as attributes of this 'FlagValues' object, through __getattr__. Both the long and short name of the original 'Flag' objects can be used to access its value: FLAGS.longname # parsed flag value FLAGS.x # parsed flag value (short name) Command line arguments are scanned and passed to the registered 'Flag' objects through the __call__ method. Unparsed arguments, including argv[0] (e.g. the program name) are returned. argv = FLAGS(sys.argv) # scan command line arguments The original registered Flag objects can be retrieved through the use of the dictionary-like operator, __getitem__: x = FLAGS['longname'] # access the registered Flag object The str() operator of a 'FlagValues' object provides help for all of the registered 'Flag' objects. """ def __init__(self): # Since everything in this class is so heavily overloaded, the only # way of defining and using fields is to access __dict__ directly. # Dictionary: flag name (string) -> Flag object. self.__dict__['__flags'] = {} # Dictionary: module name (string) -> list of Flag objects that are defined # by that module. self.__dict__['__flags_by_module'] = {} # Dictionary: module name (string) -> list of Flag objects that are # key for that module. self.__dict__['__key_flags_by_module'] = {} # Set if we should use new style gnu_getopt rather than getopt when parsing # the args. Only possible with Python 2.3+ self.UseGnuGetOpt(False) def UseGnuGetOpt(self, use_gnu_getopt=True): self.__dict__['__use_gnu_getopt'] = use_gnu_getopt def IsGnuGetOpt(self): return self.__dict__['__use_gnu_getopt'] def FlagDict(self): return self.__dict__['__flags'] def FlagsByModuleDict(self): """Returns the dictionary of module_name -> list of defined flags. Returns: A dictionary. Its keys are module names (strings). Its values are lists of Flag objects. """ return self.__dict__['__flags_by_module'] def KeyFlagsByModuleDict(self): """Returns the dictionary of module_name -> list of key flags. Returns: A dictionary. Its keys are module names (strings). Its values are lists of Flag objects. """ return self.__dict__['__key_flags_by_module'] def _RegisterFlagByModule(self, module_name, flag): """Records the module that defines a specific flag. We keep track of which flag is defined by which module so that we can later sort the flags by module. Args: module_name: A string, the name of a Python module. flag: A Flag object, a flag that is key to the module. """ flags_by_module = self.FlagsByModuleDict() flags_by_module.setdefault(module_name, []).append(flag) def _RegisterKeyFlagForModule(self, module_name, flag): """Specifies that a flag is a key flag for a module. Args: module_name: A string, the name of a Python module. flag: A Flag object, a flag that is key to the module. """ key_flags_by_module = self.KeyFlagsByModuleDict() # The list of key flags for the module named module_name. key_flags = key_flags_by_module.setdefault(module_name, []) # Add flag, but avoid duplicates. if flag not in key_flags: key_flags.append(flag) def _GetFlagsDefinedByModule(self, module): """Returns the list of flags defined by a module. Args: module: A module object or a module name (a string). Returns: A new list of Flag objects. Caller may update this list as he wishes: none of those changes will affect the internals of this FlagValue object. """ if not isinstance(module, str): module = module.__name__ return list(self.FlagsByModuleDict().get(module, [])) def _GetKeyFlagsForModule(self, module): """Returns the list of key flags for a module. Args: module: A module object or a module name (a string) Returns: A new list of Flag objects. Caller may update this list as he wishes: none of those changes will affect the internals of this FlagValue object. """ if not isinstance(module, str): module = module.__name__ # Any flag is a key flag for the module that defined it. NOTE: # key_flags is a fresh list: we can update it without affecting the # internals of this FlagValues object. key_flags = self._GetFlagsDefinedByModule(module) # Take into account flags explicitly declared as key for a module. for flag in self.KeyFlagsByModuleDict().get(module, []): if flag not in key_flags: key_flags.append(flag) return key_flags def AppendFlagValues(self, flag_values): """Appends flags registered in another FlagValues instance. Args: flag_values: registry to copy from """ for flag_name, flag in flag_values.FlagDict().iteritems(): # Each flags with shortname appears here twice (once under its # normal name, and again with its short name). To prevent # problems (DuplicateFlagError) with double flag registration, we # perform a check to make sure that the entry we're looking at is # for its normal name. if flag_name == flag.name: self[flag_name] = flag def RemoveFlagValues(self, flag_values): """Remove flags that were previously appended from another FlagValues. Args: flag_values: registry containing flags to remove. """ for flag_name in flag_values.FlagDict(): self.__delattr__(flag_name) def __setitem__(self, name, flag): """Registers a new flag variable.""" fl = self.FlagDict() if not isinstance(flag, Flag): raise IllegalFlagValue(flag) if not isinstance(name, type("")): raise FlagsError("Flag name must be a string") if len(name) == 0: raise FlagsError("Flag name cannot be empty") # If running under pychecker, duplicate keys are likely to be # defined. Disable check for duplicate keys when pycheck'ing. if (fl.has_key(name) and not flag.allow_override and not fl[name].allow_override and not _RUNNING_PYCHECKER): raise DuplicateFlagError(name, self) short_name = flag.short_name if short_name is not None: if (fl.has_key(short_name) and not flag.allow_override and not fl[short_name].allow_override and not _RUNNING_PYCHECKER): raise DuplicateFlagError(short_name, self) fl[short_name] = flag fl[name] = flag global _exported_flags _exported_flags[name] = flag def __getitem__(self, name): """Retrieves the Flag object for the flag --name.""" return self.FlagDict()[name] def __getattr__(self, name): """Retrieves the 'value' attribute of the flag --name.""" fl = self.FlagDict() if not fl.has_key(name): raise AttributeError(name) return fl[name].value def __setattr__(self, name, value): """Sets the 'value' attribute of the flag --name.""" fl = self.FlagDict() fl[name].value = value self._AssertValidators(fl[name].validators) return value def _AssertAllValidators(self): all_validators = set() for flag in self.FlagDict().itervalues(): for validator in flag.validators: all_validators.add(validator) self._AssertValidators(all_validators) def _AssertValidators(self, validators): """Assert if all validators in the list are satisfied. Asserts validators in the order they were created. Args: validators: Iterable(gflags_validators.Validator), validators to be verified Raises: AttributeError: if validators work with a non-existing flag. IllegalFlagValue: if validation fails for at least one validator """ for validator in sorted( validators, key=lambda validator: validator.insertion_index): try: validator.Verify(self) except gflags_validators.Error, e: message = validator.PrintFlagsWithValues(self) raise IllegalFlagValue('%s: %s' % (message, str(e))) def _FlagIsRegistered(self, flag_obj): """Checks whether a Flag object is registered under some name. Note: this is non trivial: in addition to its normal name, a flag may have a short name too. In self.FlagDict(), both the normal and the short name are mapped to the same flag object. E.g., calling only "del FLAGS.short_name" is not unregistering the corresponding Flag object (it is still registered under the longer name). Args: flag_obj: A Flag object. Returns: A boolean: True iff flag_obj is registered under some name. """ flag_dict = self.FlagDict() # Check whether flag_obj is registered under its long name. name = flag_obj.name if flag_dict.get(name, None) == flag_obj: return True # Check whether flag_obj is registered under its short name. short_name = flag_obj.short_name if (short_name is not None and flag_dict.get(short_name, None) == flag_obj): return True # The flag cannot be registered under any other name, so we do not # need to do a full search through the values of self.FlagDict(). return False def __delattr__(self, flag_name): """Deletes a previously-defined flag from a flag object. This method makes sure we can delete a flag by using del flag_values_object.<flag_name> E.g., flags.DEFINE_integer('foo', 1, 'Integer flag.') del flags.FLAGS.foo Args: flag_name: A string, the name of the flag to be deleted. Raises: AttributeError: When there is no registered flag named flag_name. """ fl = self.FlagDict() if flag_name not in fl: raise AttributeError(flag_name) flag_obj = fl[flag_name] del fl[flag_name] if not self._FlagIsRegistered(flag_obj): # If the Flag object indicated by flag_name is no longer # registered (please see the docstring of _FlagIsRegistered), then # we delete the occurences of the flag object in all our internal # dictionaries. self.__RemoveFlagFromDictByModule(self.FlagsByModuleDict(), flag_obj) self.__RemoveFlagFromDictByModule(self.KeyFlagsByModuleDict(), flag_obj) def __RemoveFlagFromDictByModule(self, flags_by_module_dict, flag_obj): """Removes a flag object from a module -> list of flags dictionary. Args: flags_by_module_dict: A dictionary that maps module names to lists of flags. flag_obj: A flag object. """ for unused_module, flags_in_module in flags_by_module_dict.iteritems(): # while (as opposed to if) takes care of multiple occurences of a # flag in the list for the same module. while flag_obj in flags_in_module: flags_in_module.remove(flag_obj) def SetDefault(self, name, value): """Changes the default value of the named flag object.""" fl = self.FlagDict() if not fl.has_key(name): raise AttributeError(name) fl[name].SetDefault(value) self._AssertValidators(fl[name].validators) def __contains__(self, name): """Returns True if name is a value (flag) in the dict.""" return name in self.FlagDict() has_key = __contains__ # a synonym for __contains__() def __iter__(self): return self.FlagDict().iterkeys() def __call__(self, argv): """Parses flags from argv; stores parsed flags into this FlagValues object. All unparsed arguments are returned. Flags are parsed using the GNU Program Argument Syntax Conventions, using getopt: http://www.gnu.org/software/libc/manual/html_mono/libc.html#Getopt Args: argv: argument list. Can be of any type that may be converted to a list. Returns: The list of arguments not parsed as options, including argv[0] Raises: FlagsError: on any parsing error """ # Support any sequence type that can be converted to a list argv = list(argv) shortopts = "" longopts = [] fl = self.FlagDict() # This pre parses the argv list for --flagfile=<> options. argv = argv[:1] + self.ReadFlagsFromFiles(argv[1:], force_gnu=False) # Correct the argv to support the google style of passing boolean # parameters. Boolean parameters may be passed by using --mybool, # --nomybool, --mybool=(true|false|1|0). getopt does not support # having options that may or may not have a parameter. We replace # instances of the short form --mybool and --nomybool with their # full forms: --mybool=(true|false). original_argv = list(argv) # list() makes a copy shortest_matches = None for name, flag in fl.items(): if not flag.boolean: continue if shortest_matches is None: # Determine the smallest allowable prefix for all flag names shortest_matches = self.ShortestUniquePrefixes(fl) no_name = 'no' + name prefix = shortest_matches[name] no_prefix = shortest_matches[no_name] # Replace all occurences of this boolean with extended forms for arg_idx in range(1, len(argv)): arg = argv[arg_idx] if arg.find('=') >= 0: continue if arg.startswith('--'+prefix) and ('--'+name).startswith(arg): argv[arg_idx] = ('--%s=true' % name) elif arg.startswith('--'+no_prefix) and ('--'+no_name).startswith(arg): argv[arg_idx] = ('--%s=false' % name) # Loop over all of the flags, building up the lists of short options # and long options that will be passed to getopt. Short options are # specified as a string of letters, each letter followed by a colon # if it takes an argument. Long options are stored in an array of # strings. Each string ends with an '=' if it takes an argument. for name, flag in fl.items(): longopts.append(name + "=") if len(name) == 1: # one-letter option: allow short flag type also shortopts += name if not flag.boolean: shortopts += ":" longopts.append('undefok=') undefok_flags = [] # In case --undefok is specified, loop to pick up unrecognized # options one by one. unrecognized_opts = [] args = argv[1:] while True: try: if self.__dict__['__use_gnu_getopt']: optlist, unparsed_args = getopt.gnu_getopt(args, shortopts, longopts) else: optlist, unparsed_args = getopt.getopt(args, shortopts, longopts) break except getopt.GetoptError, e: if not e.opt or e.opt in fl: # Not an unrecognized option, reraise the exception as a FlagsError raise FlagsError(e) # Remove offender from args and try again for arg_index in range(len(args)): if ((args[arg_index] == '--' + e.opt) or (args[arg_index] == '-' + e.opt) or (args[arg_index].startswith('--' + e.opt + '='))): unrecognized_opts.append((e.opt, args[arg_index])) args = args[0:arg_index] + args[arg_index+1:] break else: # We should have found the option, so we don't expect to get # here. We could assert, but raising the original exception # might work better. raise FlagsError(e) for name, arg in optlist: if name == '--undefok': flag_names = arg.split(',') undefok_flags.extend(flag_names) # For boolean flags, if --undefok=boolflag is specified, then we should # also accept --noboolflag, in addition to --boolflag. # Since we don't know the type of the undefok'd flag, this will affect # non-boolean flags as well. # NOTE: You shouldn't use --undefok=noboolflag, because then we will # accept --nonoboolflag here. We are choosing not to do the conversion # from noboolflag -> boolflag because of the ambiguity that flag names # can start with 'no'. undefok_flags.extend('no' + name for name in flag_names) continue if name.startswith('--'): # long option name = name[2:] short_option = 0 else: # short option name = name[1:] short_option = 1 if fl.has_key(name): flag = fl[name] if flag.boolean and short_option: arg = 1 flag.Parse(arg) # If there were unrecognized options, raise an exception unless # the options were named via --undefok. for opt, value in unrecognized_opts: if opt not in undefok_flags: raise UnrecognizedFlagError(opt, value) if unparsed_args: if self.__dict__['__use_gnu_getopt']: # if using gnu_getopt just return the program name + remainder of argv. ret_val = argv[:1] + unparsed_args else: # unparsed_args becomes the first non-flag detected by getopt to # the end of argv. Because argv may have been modified above, # return original_argv for this region. ret_val = argv[:1] + original_argv[-len(unparsed_args):] else: ret_val = argv[:1] self._AssertAllValidators() return ret_val def Reset(self): """Resets the values to the point before FLAGS(argv) was called.""" for f in self.FlagDict().values(): f.Unparse() def RegisteredFlags(self): """Returns: a list of the names and short names of all registered flags.""" return self.FlagDict().keys() def FlagValuesDict(self): """Returns: a dictionary that maps flag names to flag values.""" flag_values = {} for flag_name in self.RegisteredFlags(): flag = self.FlagDict()[flag_name] flag_values[flag_name] = flag.value return flag_values def __str__(self): """Generates a help string for all known flags.""" return self.GetHelp() def GetHelp(self, prefix=''): """Generates a help string for all known flags.""" helplist = [] flags_by_module = self.FlagsByModuleDict() if flags_by_module: modules = flags_by_module.keys() modules.sort() # Print the help for the main module first, if possible. main_module = _GetMainModule() if main_module in modules: modules.remove(main_module) modules = [main_module] + modules for module in modules: self.__RenderOurModuleFlags(module, helplist) self.__RenderModuleFlags('gflags', _SPECIAL_FLAGS.FlagDict().values(), helplist) else: # Just print one long list of flags. self.__RenderFlagList( self.FlagDict().values() + _SPECIAL_FLAGS.FlagDict().values(), helplist, prefix) return '\n'.join(helplist) def __RenderModuleFlags(self, module, flags, output_lines, prefix=""): """Generates a help string for a given module.""" if not isinstance(module, str): module = module.__name__ output_lines.append('\n%s%s:' % (prefix, module)) self.__RenderFlagList(flags, output_lines, prefix + " ") def __RenderOurModuleFlags(self, module, output_lines, prefix=""): """Generates a help string for a given module.""" flags = self._GetFlagsDefinedByModule(module) if flags: self.__RenderModuleFlags(module, flags, output_lines, prefix) def __RenderOurModuleKeyFlags(self, module, output_lines, prefix=""): """Generates a help string for the key flags of a given module. Args: module: A module object or a module name (a string). output_lines: A list of strings. The generated help message lines will be appended to this list. prefix: A string that is prepended to each generated help line. """ key_flags = self._GetKeyFlagsForModule(module) if key_flags: self.__RenderModuleFlags(module, key_flags, output_lines, prefix) def ModuleHelp(self, module): """Describe the key flags of a module. Args: module: A module object or a module name (a string). Returns: string describing the key flags of a module. """ helplist = [] self.__RenderOurModuleKeyFlags(module, helplist) return '\n'.join(helplist) def MainModuleHelp(self): """Describe the key flags of the main module. Returns: string describing the key flags of a module. """ return self.ModuleHelp(_GetMainModule()) def __RenderFlagList(self, flaglist, output_lines, prefix=" "): fl = self.FlagDict() special_fl = _SPECIAL_FLAGS.FlagDict() flaglist = [(flag.name, flag) for flag in flaglist] flaglist.sort() flagset = {} for (name, flag) in flaglist: # It's possible this flag got deleted or overridden since being # registered in the per-module flaglist. Check now against the # canonical source of current flag information, the FlagDict. if fl.get(name, None) != flag and special_fl.get(name, None) != flag: # a different flag is using this name now continue # only print help once if flagset.has_key(flag): continue flagset[flag] = 1 flaghelp = "" if flag.short_name: flaghelp += "-%s," % flag.short_name if flag.boolean: flaghelp += "--[no]%s" % flag.name + ":" else: flaghelp += "--%s" % flag.name + ":" flaghelp += " " if flag.help: flaghelp += flag.help flaghelp = TextWrap(flaghelp, indent=prefix+" ", firstline_indent=prefix) if flag.default_as_str: flaghelp += "\n" flaghelp += TextWrap("(default: %s)" % flag.default_as_str, indent=prefix+" ") if flag.parser.syntactic_help: flaghelp += "\n" flaghelp += TextWrap("(%s)" % flag.parser.syntactic_help, indent=prefix+" ") output_lines.append(flaghelp) def get(self, name, default): """Returns the value of a flag (if not None) or a default value. Args: name: A string, the name of a flag. default: Default value to use if the flag value is None. """ value = self.__getattr__(name) if value is not None: # Can't do if not value, b/c value might be '0' or "" return value else: return default def ShortestUniquePrefixes(self, fl): """Returns: dictionary; maps flag names to their shortest unique prefix.""" # Sort the list of flag names sorted_flags = [] for name, flag in fl.items(): sorted_flags.append(name) if flag.boolean: sorted_flags.append('no%s' % name) sorted_flags.sort() # For each name in the sorted list, determine the shortest unique # prefix by comparing itself to the next name and to the previous # name (the latter check uses cached info from the previous loop). shortest_matches = {} prev_idx = 0 for flag_idx in range(len(sorted_flags)): curr = sorted_flags[flag_idx] if flag_idx == (len(sorted_flags) - 1): next = None else: next = sorted_flags[flag_idx+1] next_len = len(next) for curr_idx in range(len(curr)): if (next is None or curr_idx >= next_len or curr[curr_idx] != next[curr_idx]): # curr longer than next or no more chars in common shortest_matches[curr] = curr[:max(prev_idx, curr_idx) + 1] prev_idx = curr_idx break else: # curr shorter than (or equal to) next shortest_matches[curr] = curr prev_idx = curr_idx + 1 # next will need at least one more char return shortest_matches def __IsFlagFileDirective(self, flag_string): """Checks whether flag_string contain a --flagfile=<foo> directive.""" if isinstance(flag_string, type("")): if flag_string.startswith('--flagfile='): return 1 elif flag_string == '--flagfile': return 1 elif flag_string.startswith('-flagfile='): return 1 elif flag_string == '-flagfile': return 1 else: return 0 return 0 def ExtractFilename(self, flagfile_str): """Returns filename from a flagfile_str of form -[-]flagfile=filename. The cases of --flagfile foo and -flagfile foo shouldn't be hitting this function, as they are dealt with in the level above this function. """ if flagfile_str.startswith('--flagfile='): return os.path.expanduser((flagfile_str[(len('--flagfile=')):]).strip()) elif flagfile_str.startswith('-flagfile='): return os.path.expanduser((flagfile_str[(len('-flagfile=')):]).strip()) else: raise FlagsError('Hit illegal --flagfile type: %s' % flagfile_str) def __GetFlagFileLines(self, filename, parsed_file_list): """Returns the useful (!=comments, etc) lines from a file with flags. Args: filename: A string, the name of the flag file. parsed_file_list: A list of the names of the files we have already read. MUTATED BY THIS FUNCTION. Returns: List of strings. See the note below. NOTE(springer): This function checks for a nested --flagfile=<foo> tag and handles the lower file recursively. It returns a list of all the lines that _could_ contain command flags. This is EVERYTHING except whitespace lines and comments (lines starting with '#' or '//'). """ line_list = [] # All line from flagfile. flag_line_list = [] # Subset of lines w/o comments, blanks, flagfile= tags. try: file_obj = open(filename, 'r') except IOError, e_msg: print e_msg print 'ERROR:: Unable to open flagfile: %s' % (filename) return flag_line_list line_list = file_obj.readlines() file_obj.close() parsed_file_list.append(filename) # This is where we check each line in the file we just read. for line in line_list: if line.isspace(): pass # Checks for comment (a line that starts with '#'). elif line.startswith('#') or line.startswith('//'): pass # Checks for a nested "--flagfile=<bar>" flag in the current file. # If we find one, recursively parse down into that file. elif self.__IsFlagFileDirective(line): sub_filename = self.ExtractFilename(line) # We do a little safety check for reparsing a file we've already done. if not sub_filename in parsed_file_list: included_flags = self.__GetFlagFileLines(sub_filename, parsed_file_list) flag_line_list.extend(included_flags) else: # Case of hitting a circularly included file. print >>sys.stderr, ('Warning: Hit circular flagfile dependency: %s' % sub_filename) else: # Any line that's not a comment or a nested flagfile should get # copied into 2nd position. This leaves earlier arguements # further back in the list, thus giving them higher priority. flag_line_list.append(line.strip()) return flag_line_list def ReadFlagsFromFiles(self, argv, force_gnu=True): """Processes command line args, but also allow args to be read from file. Args: argv: A list of strings, usually sys.argv[1:], which may contain one or more flagfile directives of the form --flagfile="./filename". Note that the name of the program (sys.argv[0]) should be omitted. force_gnu: If False, --flagfile parsing obeys normal flag semantics. If True, --flagfile parsing instead follows gnu_getopt semantics. *** WARNING *** force_gnu=False may become the future default! Returns: A new list which has the original list combined with what we read from any flagfile(s). References: Global gflags.FLAG class instance. This function should be called before the normal FLAGS(argv) call. This function scans the input list for a flag that looks like: --flagfile=<somefile>. Then it opens <somefile>, reads all valid key and value pairs and inserts them into the input list between the first item of the list and any subsequent items in the list. Note that your application's flags are still defined the usual way using gflags DEFINE_flag() type functions. Notes (assuming we're getting a commandline of some sort as our input): --> Flags from the command line argv _should_ always take precedence! --> A further "--flagfile=<otherfile.cfg>" CAN be nested in a flagfile. It will be processed after the parent flag file is done. --> For duplicate flags, first one we hit should "win". --> In a flagfile, a line beginning with # or // is a comment. --> Entirely blank lines _should_ be ignored. """ parsed_file_list = [] rest_of_args = argv new_argv = [] while rest_of_args: current_arg = rest_of_args[0] rest_of_args = rest_of_args[1:] if self.__IsFlagFileDirective(current_arg): # This handles the case of -(-)flagfile foo. In this case the # next arg really is part of this one. if current_arg == '--flagfile' or current_arg == '-flagfile': if not rest_of_args: raise IllegalFlagValue('--flagfile with no argument') flag_filename = os.path.expanduser(rest_of_args[0]) rest_of_args = rest_of_args[1:] else: # This handles the case of (-)-flagfile=foo. flag_filename = self.ExtractFilename(current_arg) new_argv[0:0] = self.__GetFlagFileLines(flag_filename, parsed_file_list) else: new_argv.append(current_arg) # Stop parsing after '--', like getopt and gnu_getopt. if current_arg == '--': break # Stop parsing after a non-flag, like getopt. if not current_arg.startswith('-'): if not force_gnu and not self.__dict__['__use_gnu_getopt']: break if rest_of_args: new_argv.extend(rest_of_args) return new_argv def FlagsIntoString(self): """Returns a string with the flags assignments from this FlagValues object. This function ignores flags whose value is None. Each flag assignment is separated by a newline. NOTE: MUST mirror the behavior of the C++ function CommandlineFlagsIntoString from google3/base/commandlineflags.cc. """ s = '' for flag in self.FlagDict().values(): if flag.value is not None: s += flag.Serialize() + '\n' return s def AppendFlagsIntoFile(self, filename): """Appends all flags assignments from this FlagInfo object to a file. Output will be in the format of a flagfile. NOTE: MUST mirror the behavior of the C++ version of AppendFlagsIntoFile from google3/base/commandlineflags.cc. """ out_file = open(filename, 'a') out_file.write(self.FlagsIntoString()) out_file.close() def WriteHelpInXMLFormat(self, outfile=None): """Outputs flag documentation in XML format. NOTE: We use element names that are consistent with those used by the C++ command-line flag library, from google3/base/commandlineflags_reporting.cc. We also use a few new elements (e.g., <key>), but we do not interfere / overlap with existing XML elements used by the C++ library. Please maintain this consistency. Args: outfile: File object we write to. Default None means sys.stdout. """ outfile = outfile or sys.stdout outfile.write('<?xml version=\"1.0\"?>\n') outfile.write('<AllFlags>\n') indent = ' ' _WriteSimpleXMLElement(outfile, 'program', os.path.basename(sys.argv[0]), indent) usage_doc = sys.modules['__main__'].__doc__ if not usage_doc: usage_doc = '\nUSAGE: %s [flags]\n' % sys.argv[0] else: usage_doc = usage_doc.replace('%s', sys.argv[0]) _WriteSimpleXMLElement(outfile, 'usage', usage_doc, indent) # Get list of key flags for the main module. key_flags = self._GetKeyFlagsForModule(_GetMainModule()) # Sort flags by declaring module name and next by flag name. flags_by_module = self.FlagsByModuleDict() all_module_names = list(flags_by_module.keys()) all_module_names.sort() for module_name in all_module_names: flag_list = [(f.name, f) for f in flags_by_module[module_name]] flag_list.sort() for unused_flag_name, flag in flag_list: is_key = flag in key_flags flag.WriteInfoInXMLFormat(outfile, module_name, is_key=is_key, indent=indent) outfile.write('</AllFlags>\n') outfile.flush() def AddValidator(self, validator): """Register new flags validator to be checked. Args: validator: gflags_validators.Validator Raises: AttributeError: if validators work with a non-existing flag. """ for flag_name in validator.GetFlagsNames(): flag = self.FlagDict()[flag_name] flag.validators.append(validator) # end of FlagValues definition # The global FlagValues instance FLAGS = FlagValues() def _MakeXMLSafe(s): """Escapes <, >, and & from s, and removes XML 1.0-illegal chars.""" s = cgi.escape(s) # Escape <, >, and & # Remove characters that cannot appear in an XML 1.0 document # (http://www.w3.org/TR/REC-xml/#charsets). # # NOTE: if there are problems with current solution, one may move to # XML 1.1, which allows such chars, if they're entity-escaped (&#xHH;). s = re.sub(r'[\x00-\x08\x0b\x0c\x0e-\x1f]', '', s) return s def _WriteSimpleXMLElement(outfile, name, value, indent): """Writes a simple XML element. Args: outfile: File object we write the XML element to. name: A string, the name of XML element. value: A Python object, whose string representation will be used as the value of the XML element. indent: A string, prepended to each line of generated output. """ value_str = str(value) if isinstance(value, bool): # Display boolean values as the C++ flag library does: no caps. value_str = value_str.lower() outfile.write('%s<%s>%s</%s>\n' % (indent, name, _MakeXMLSafe(value_str), name)) class Flag: """Information about a command-line flag. 'Flag' objects define the following fields: .name - the name for this flag .default - the default value for this flag .default_as_str - default value as repr'd string, e.g., "'true'" (or None) .value - the most recent parsed value of this flag; set by Parse() .help - a help string or None if no help is available .short_name - the single letter alias for this flag (or None) .boolean - if 'true', this flag does not accept arguments .present - true if this flag was parsed from command line flags. .parser - an ArgumentParser object .serializer - an ArgumentSerializer object .allow_override - the flag may be redefined without raising an error The only public method of a 'Flag' object is Parse(), but it is typically only called by a 'FlagValues' object. The Parse() method is a thin wrapper around the 'ArgumentParser' Parse() method. The parsed value is saved in .value, and the .present attribute is updated. If this flag was already present, a FlagsError is raised. Parse() is also called during __init__ to parse the default value and initialize the .value attribute. This enables other python modules to safely use flags even if the __main__ module neglects to parse the command line arguments. The .present attribute is cleared after __init__ parsing. If the default value is set to None, then the __init__ parsing step is skipped and the .value attribute is initialized to None. Note: The default value is also presented to the user in the help string, so it is important that it be a legal value for this flag. """ def __init__(self, parser, serializer, name, default, help_string, short_name=None, boolean=0, allow_override=0): self.name = name if not help_string: help_string = '(no help available)' self.help = help_string self.short_name = short_name self.boolean = boolean self.present = 0 self.parser = parser self.serializer = serializer self.allow_override = allow_override self.value = None self.validators = [] self.SetDefault(default) def __GetParsedValueAsString(self, value): if value is None: return None if self.serializer: return repr(self.serializer.Serialize(value)) if self.boolean: if value: return repr('true') else: return repr('false') return repr(str(value)) def Parse(self, argument): try: self.value = self.parser.Parse(argument) except ValueError, e: # recast ValueError as IllegalFlagValue raise IllegalFlagValue("flag --%s=%s: %s" % (self.name, argument, e)) self.present += 1 def Unparse(self): if self.default is None: self.value = None else: self.Parse(self.default) self.present = 0 def Serialize(self): if self.value is None: return '' if self.boolean: if self.value: return "--%s" % self.name else: return "--no%s" % self.name else: if not self.serializer: raise FlagsError("Serializer not present for flag %s" % self.name) return "--%s=%s" % (self.name, self.serializer.Serialize(self.value)) def SetDefault(self, value): """Changes the default value (and current value too) for this Flag.""" # We can't allow a None override because it may end up not being # passed to C++ code when we're overriding C++ flags. So we # cowardly bail out until someone fixes the semantics of trying to # pass None to a C++ flag. See swig_flags.Init() for details on # this behavior. # TODO(olexiy): Users can directly call this method, bypassing all flags # validators (we don't have FlagValues here, so we can not check # validators). # The simplest solution I see is to make this method private. # Another approach would be to store reference to the corresponding # FlagValues with each flag, but this seems to be an overkill. if value is None and self.allow_override: raise DuplicateFlagCannotPropagateNoneToSwig(self.name) self.default = value self.Unparse() self.default_as_str = self.__GetParsedValueAsString(self.value) def Type(self): """Returns: a string that describes the type of this Flag.""" # NOTE: we use strings, and not the types.*Type constants because # our flags can have more exotic types, e.g., 'comma separated list # of strings', 'whitespace separated list of strings', etc. return self.parser.Type() def WriteInfoInXMLFormat(self, outfile, module_name, is_key=False, indent=''): """Writes common info about this flag, in XML format. This is information that is relevant to all flags (e.g., name, meaning, etc.). If you defined a flag that has some other pieces of info, then please override _WriteCustomInfoInXMLFormat. Please do NOT override this method. Args: outfile: File object we write to. module_name: A string, the name of the module that defines this flag. is_key: A boolean, True iff this flag is key for main module. indent: A string that is prepended to each generated line. """ outfile.write(indent + '<flag>\n') inner_indent = indent + ' ' if is_key: _WriteSimpleXMLElement(outfile, 'key', 'yes', inner_indent) _WriteSimpleXMLElement(outfile, 'file', module_name, inner_indent) # Print flag features that are relevant for all flags. _WriteSimpleXMLElement(outfile, 'name', self.name, inner_indent) if self.short_name: _WriteSimpleXMLElement(outfile, 'short_name', self.short_name, inner_indent) if self.help: _WriteSimpleXMLElement(outfile, 'meaning', self.help, inner_indent) # The default flag value can either be represented as a string like on the # command line, or as a Python object. We serialize this value in the # latter case in order to remain consistent. if self.serializer and not isinstance(self.default, str): default_serialized = self.serializer.Serialize(self.default) else: default_serialized = self.default _WriteSimpleXMLElement(outfile, 'default', default_serialized, inner_indent) _WriteSimpleXMLElement(outfile, 'current', self.value, inner_indent) _WriteSimpleXMLElement(outfile, 'type', self.Type(), inner_indent) # Print extra flag features this flag may have. self._WriteCustomInfoInXMLFormat(outfile, inner_indent) outfile.write(indent + '</flag>\n') def _WriteCustomInfoInXMLFormat(self, outfile, indent): """Writes extra info about this flag, in XML format. "Extra" means "not already printed by WriteInfoInXMLFormat above." Args: outfile: File object we write to. indent: A string that is prepended to each generated line. """ # Usually, the parser knows the extra details about the flag, so # we just forward the call to it. self.parser.WriteCustomInfoInXMLFormat(outfile, indent) # End of Flag definition class _ArgumentParserCache(type): """Metaclass used to cache and share argument parsers among flags.""" _instances = {} def __call__(mcs, *args, **kwargs): """Returns an instance of the argument parser cls. This method overrides behavior of the __new__ methods in all subclasses of ArgumentParser (inclusive). If an instance for mcs with the same set of arguments exists, this instance is returned, otherwise a new instance is created. If any keyword arguments are defined, or the values in args are not hashable, this method always returns a new instance of cls. Args: args: Positional initializer arguments. kwargs: Initializer keyword arguments. Returns: An instance of cls, shared or new. """ if kwargs: return type.__call__(mcs, *args, **kwargs) else: instances = mcs._instances key = (mcs,) + tuple(args) try: return instances[key] except KeyError: # No cache entry for key exists, create a new one. return instances.setdefault(key, type.__call__(mcs, *args)) except TypeError: # An object in args cannot be hashed, always return # a new instance. return type.__call__(mcs, *args) class ArgumentParser(object): """Base class used to parse and convert arguments. The Parse() method checks to make sure that the string argument is a legal value and convert it to a native type. If the value cannot be converted, it should throw a 'ValueError' exception with a human readable explanation of why the value is illegal. Subclasses should also define a syntactic_help string which may be presented to the user to describe the form of the legal values. Argument parser classes must be stateless, since instances are cached and shared between flags. Initializer arguments are allowed, but all member variables must be derived from initializer arguments only. """ __metaclass__ = _ArgumentParserCache syntactic_help = "" def Parse(self, argument): """Default implementation: always returns its argument unmodified.""" return argument def Type(self): return 'string' def WriteCustomInfoInXMLFormat(self, outfile, indent): pass class ArgumentSerializer: """Base class for generating string representations of a flag value.""" def Serialize(self, value): return str(value) class ListSerializer(ArgumentSerializer): def __init__(self, list_sep): self.list_sep = list_sep def Serialize(self, value): return self.list_sep.join([str(x) for x in value]) # Flags validators def RegisterValidator(flag_name, checker, message='Flag validation failed', flag_values=FLAGS): """Adds a constraint, which will be enforced during program execution. The constraint is validated when flags are initially parsed, and after each change of the corresponding flag's value. Args: flag_name: string, name of the flag to be checked. checker: method to validate the flag. input - value of the corresponding flag (string, boolean, etc. This value will be passed to checker by the library). See file's docstring for examples. output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise gflags_validators.Error(desired_error_message). message: error text to be shown to the user if checker returns False. If checker raises gflags_validators.Error, message from the raised Error will be shown. flag_values: FlagValues Raises: AttributeError: if flag_name is not registered as a valid flag name. """ flag_values.AddValidator(gflags_validators.SimpleValidator(flag_name, checker, message)) def MarkFlagAsRequired(flag_name, flag_values=FLAGS): """Ensure that flag is not None during program execution. Registers a flag validator, which will follow usual validator rules. Args: flag_name: string, name of the flag flag_values: FlagValues Raises: AttributeError: if flag_name is not registered as a valid flag name. """ RegisterValidator(flag_name, lambda value: value is not None, message='Flag --%s must be specified.' % flag_name, flag_values=flag_values) def _RegisterBoundsValidatorIfNeeded(parser, name, flag_values): """Enforce lower and upper bounds for numeric flags. Args: parser: NumericParser (either FloatParser or IntegerParser). Provides lower and upper bounds, and help text to display. name: string, name of the flag flag_values: FlagValues """ if parser.lower_bound is not None or parser.upper_bound is not None: def Checker(value): if value is not None and parser.IsOutsideBounds(value): message = '%s is not %s' % (value, parser.syntactic_help) raise gflags_validators.Error(message) return True RegisterValidator(name, Checker, flag_values=flag_values) # The DEFINE functions are explained in mode details in the module doc string. def DEFINE(parser, name, default, help, flag_values=FLAGS, serializer=None, **args): """Registers a generic Flag object. NOTE: in the docstrings of all DEFINE* functions, "registers" is short for "creates a new flag and registers it". Auxiliary function: clients should use the specialized DEFINE_<type> function instead. Args: parser: ArgumentParser that is used to parse the flag arguments. name: A string, the flag name. default: The default value of the flag. help: A help string. flag_values: FlagValues object the flag will be registered with. serializer: ArgumentSerializer that serializes the flag value. args: Dictionary with extra keyword args that are passes to the Flag __init__. """ DEFINE_flag(Flag(parser, serializer, name, default, help, **args), flag_values) def DEFINE_flag(flag, flag_values=FLAGS): """Registers a 'Flag' object with a 'FlagValues' object. By default, the global FLAGS 'FlagValue' object is used. Typical users will use one of the more specialized DEFINE_xxx functions, such as DEFINE_string or DEFINE_integer. But developers who need to create Flag objects themselves should use this function to register their flags. """ # copying the reference to flag_values prevents pychecker warnings fv = flag_values fv[flag.name] = flag # Tell flag_values who's defining the flag. if isinstance(flag_values, FlagValues): # Regarding the above isinstance test: some users pass funny # values of flag_values (e.g., {}) in order to avoid the flag # registration (in the past, there used to be a flag_values == # FLAGS test here) and redefine flags with the same name (e.g., # debug). To avoid breaking their code, we perform the # registration only if flag_values is a real FlagValues object. flag_values._RegisterFlagByModule(_GetCallingModule(), flag) def _InternalDeclareKeyFlags(flag_names, flag_values=FLAGS, key_flag_values=None): """Declares a flag as key for the calling module. Internal function. User code should call DECLARE_key_flag or ADOPT_module_key_flags instead. Args: flag_names: A list of strings that are names of already-registered Flag objects. flag_values: A FlagValues object that the flags listed in flag_names have registered with (the value of the flag_values argument from the DEFINE_* calls that defined those flags). This should almost never need to be overridden. key_flag_values: A FlagValues object that (among possibly many other things) keeps track of the key flags for each module. Default None means "same as flag_values". This should almost never need to be overridden. Raises: UnrecognizedFlagError: when we refer to a flag that was not defined yet. """ key_flag_values = key_flag_values or flag_values module = _GetCallingModule() for flag_name in flag_names: if flag_name not in flag_values: raise UnrecognizedFlagError(flag_name) flag = flag_values.FlagDict()[flag_name] key_flag_values._RegisterKeyFlagForModule(module, flag) def DECLARE_key_flag(flag_name, flag_values=FLAGS): """Declares one flag as key to the current module. Key flags are flags that are deemed really important for a module. They are important when listing help messages; e.g., if the --helpshort command-line flag is used, then only the key flags of the main module are listed (instead of all flags, as in the case of --help). Sample usage: flags.DECLARED_key_flag('flag_1') Args: flag_name: A string, the name of an already declared flag. (Redeclaring flags as key, including flags implicitly key because they were declared in this module, is a no-op.) flag_values: A FlagValues object. This should almost never need to be overridden. """ if flag_name in _SPECIAL_FLAGS: # Take care of the special flags, e.g., --flagfile, --undefok. # These flags are defined in _SPECIAL_FLAGS, and are treated # specially during flag parsing, taking precedence over the # user-defined flags. _InternalDeclareKeyFlags([flag_name], flag_values=_SPECIAL_FLAGS, key_flag_values=flag_values) return _InternalDeclareKeyFlags([flag_name], flag_values=flag_values) def ADOPT_module_key_flags(module, flag_values=FLAGS): """Declares that all flags key to a module are key to the current module. Args: module: A module object. flag_values: A FlagValues object. This should almost never need to be overridden. Raises: FlagsError: When given an argument that is a module name (a string), instead of a module object. """ # NOTE(salcianu): an even better test would be if not # isinstance(module, types.ModuleType) but I didn't want to import # types for such a tiny use. if isinstance(module, str): raise FlagsError('Received module name %s; expected a module object.' % module) _InternalDeclareKeyFlags( [f.name for f in flag_values._GetKeyFlagsForModule(module.__name__)], flag_values=flag_values) # If module is this flag module, take _SPECIAL_FLAGS into account. if module == _GetThisModuleObjectAndName()[0]: _InternalDeclareKeyFlags( # As we associate flags with _GetCallingModule(), the special # flags defined in this module are incorrectly registered with # a different module. So, we can't use _GetKeyFlagsForModule. # Instead, we take all flags from _SPECIAL_FLAGS (a private # FlagValues, where no other module should register flags). [f.name for f in _SPECIAL_FLAGS.FlagDict().values()], flag_values=_SPECIAL_FLAGS, key_flag_values=flag_values) # # STRING FLAGS # def DEFINE_string(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value can be any string.""" parser = ArgumentParser() serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) # # BOOLEAN FLAGS # # and the special HELP flags. class BooleanParser(ArgumentParser): """Parser of boolean values.""" def Convert(self, argument): """Converts the argument to a boolean; raise ValueError on errors.""" if type(argument) == str: if argument.lower() in ['true', 't', '1']: return True elif argument.lower() in ['false', 'f', '0']: return False bool_argument = bool(argument) if argument == bool_argument: # The argument is a valid boolean (True, False, 0, or 1), and not just # something that always converts to bool (list, string, int, etc.). return bool_argument raise ValueError('Non-boolean argument to boolean flag', argument) def Parse(self, argument): val = self.Convert(argument) return val def Type(self): return 'bool' class BooleanFlag(Flag): """Basic boolean flag. Boolean flags do not take any arguments, and their value is either True (1) or False (0). The false value is specified on the command line by prepending the word 'no' to either the long or the short flag name. For example, if a Boolean flag was created whose long name was 'update' and whose short name was 'x', then this flag could be explicitly unset through either --noupdate or --nox. """ def __init__(self, name, default, help, short_name=None, **args): p = BooleanParser() Flag.__init__(self, p, None, name, default, help, short_name, 1, **args) if not self.help: self.help = "a boolean value" def DEFINE_boolean(name, default, help, flag_values=FLAGS, **args): """Registers a boolean flag. Such a boolean flag does not take an argument. If a user wants to specify a false value explicitly, the long option beginning with 'no' must be used: i.e. --noflag This flag will have a value of None, True or False. None is possible if default=None and the user does not specify the flag on the command line. """ DEFINE_flag(BooleanFlag(name, default, help, **args), flag_values) # Match C++ API to unconfuse C++ people. DEFINE_bool = DEFINE_boolean class HelpFlag(BooleanFlag): """ HelpFlag is a special boolean flag that prints usage information and raises a SystemExit exception if it is ever found in the command line arguments. Note this is called with allow_override=1, so other apps can define their own --help flag, replacing this one, if they want. """ def __init__(self): BooleanFlag.__init__(self, "help", 0, "show this help", short_name="?", allow_override=1) def Parse(self, arg): if arg: doc = sys.modules["__main__"].__doc__ flags = str(FLAGS) print doc or ("\nUSAGE: %s [flags]\n" % sys.argv[0]) if flags: print "flags:" print flags sys.exit(1) class HelpXMLFlag(BooleanFlag): """Similar to HelpFlag, but generates output in XML format.""" def __init__(self): BooleanFlag.__init__(self, 'helpxml', False, 'like --help, but generates XML output', allow_override=1) def Parse(self, arg): if arg: FLAGS.WriteHelpInXMLFormat(sys.stdout) sys.exit(1) class HelpshortFlag(BooleanFlag): """ HelpshortFlag is a special boolean flag that prints usage information for the "main" module, and rasies a SystemExit exception if it is ever found in the command line arguments. Note this is called with allow_override=1, so other apps can define their own --helpshort flag, replacing this one, if they want. """ def __init__(self): BooleanFlag.__init__(self, "helpshort", 0, "show usage only for this module", allow_override=1) def Parse(self, arg): if arg: doc = sys.modules["__main__"].__doc__ flags = FLAGS.MainModuleHelp() print doc or ("\nUSAGE: %s [flags]\n" % sys.argv[0]) if flags: print "flags:" print flags sys.exit(1) # # Numeric parser - base class for Integer and Float parsers # class NumericParser(ArgumentParser): """Parser of numeric values. Parsed value may be bounded to a given upper and lower bound. """ def IsOutsideBounds(self, val): return ((self.lower_bound is not None and val < self.lower_bound) or (self.upper_bound is not None and val > self.upper_bound)) def Parse(self, argument): val = self.Convert(argument) if self.IsOutsideBounds(val): raise ValueError("%s is not %s" % (val, self.syntactic_help)) return val def WriteCustomInfoInXMLFormat(self, outfile, indent): if self.lower_bound is not None: _WriteSimpleXMLElement(outfile, 'lower_bound', self.lower_bound, indent) if self.upper_bound is not None: _WriteSimpleXMLElement(outfile, 'upper_bound', self.upper_bound, indent) def Convert(self, argument): """Default implementation: always returns its argument unmodified.""" return argument # End of Numeric Parser # # FLOAT FLAGS # class FloatParser(NumericParser): """Parser of floating point values. Parsed value may be bounded to a given upper and lower bound. """ number_article = "a" number_name = "number" syntactic_help = " ".join((number_article, number_name)) def __init__(self, lower_bound=None, upper_bound=None): super(FloatParser, self).__init__() self.lower_bound = lower_bound self.upper_bound = upper_bound sh = self.syntactic_help if lower_bound is not None and upper_bound is not None: sh = ("%s in the range [%s, %s]" % (sh, lower_bound, upper_bound)) elif lower_bound == 0: sh = "a non-negative %s" % self.number_name elif upper_bound == 0: sh = "a non-positive %s" % self.number_name elif upper_bound is not None: sh = "%s <= %s" % (self.number_name, upper_bound) elif lower_bound is not None: sh = "%s >= %s" % (self.number_name, lower_bound) self.syntactic_help = sh def Convert(self, argument): """Converts argument to a float; raises ValueError on errors.""" return float(argument) def Type(self): return 'float' # End of FloatParser def DEFINE_float(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value must be a float. If lower_bound or upper_bound are set, then this flag must be within the given range. """ parser = FloatParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) _RegisterBoundsValidatorIfNeeded(parser, name, flag_values=flag_values) # # INTEGER FLAGS # class IntegerParser(NumericParser): """Parser of an integer value. Parsed value may be bounded to a given upper and lower bound. """ number_article = "an" number_name = "integer" syntactic_help = " ".join((number_article, number_name)) def __init__(self, lower_bound=None, upper_bound=None): super(IntegerParser, self).__init__() self.lower_bound = lower_bound self.upper_bound = upper_bound sh = self.syntactic_help if lower_bound is not None and upper_bound is not None: sh = ("%s in the range [%s, %s]" % (sh, lower_bound, upper_bound)) elif lower_bound == 1: sh = "a positive %s" % self.number_name elif upper_bound == -1: sh = "a negative %s" % self.number_name elif lower_bound == 0: sh = "a non-negative %s" % self.number_name elif upper_bound == 0: sh = "a non-positive %s" % self.number_name elif upper_bound is not None: sh = "%s <= %s" % (self.number_name, upper_bound) elif lower_bound is not None: sh = "%s >= %s" % (self.number_name, lower_bound) self.syntactic_help = sh def Convert(self, argument): __pychecker__ = 'no-returnvalues' if type(argument) == str: base = 10 if len(argument) > 2 and argument[0] == "0" and argument[1] == "x": base = 16 try: return int(argument, base) # ValueError is thrown when argument is a string, and overflows an int. except ValueError: return long(argument, base) else: try: return int(argument) # OverflowError is thrown when argument is numeric, and overflows an int. except OverflowError: return long(argument) def Type(self): return 'int' def DEFINE_integer(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value must be an integer. If lower_bound, or upper_bound are set, then this flag must be within the given range. """ parser = IntegerParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) _RegisterBoundsValidatorIfNeeded(parser, name, flag_values=flag_values) # # ENUM FLAGS # class EnumParser(ArgumentParser): """Parser of a string enum value (a string value from a given set). If enum_values (see below) is not specified, any string is allowed. """ def __init__(self, enum_values=None): super(EnumParser, self).__init__() self.enum_values = enum_values def Parse(self, argument): if self.enum_values and argument not in self.enum_values: raise ValueError("value should be one of <%s>" % "|".join(self.enum_values)) return argument def Type(self): return 'string enum' class EnumFlag(Flag): """Basic enum flag; its value can be any string from list of enum_values.""" def __init__(self, name, default, help, enum_values=None, short_name=None, **args): enum_values = enum_values or [] p = EnumParser(enum_values) g = ArgumentSerializer() Flag.__init__(self, p, g, name, default, help, short_name, **args) if not self.help: self.help = "an enum string" self.help = "<%s>: %s" % ("|".join(enum_values), self.help) def _WriteCustomInfoInXMLFormat(self, outfile, indent): for enum_value in self.parser.enum_values: _WriteSimpleXMLElement(outfile, 'enum_value', enum_value, indent) def DEFINE_enum(name, default, enum_values, help, flag_values=FLAGS, **args): """Registers a flag whose value can be any string from enum_values.""" DEFINE_flag(EnumFlag(name, default, help, enum_values, ** args), flag_values) # # LIST FLAGS # class BaseListParser(ArgumentParser): """Base class for a parser of lists of strings. To extend, inherit from this class; from the subclass __init__, call BaseListParser.__init__(self, token, name) where token is a character used to tokenize, and name is a description of the separator. """ def __init__(self, token=None, name=None): assert name super(BaseListParser, self).__init__() self._token = token self._name = name self.syntactic_help = "a %s separated list" % self._name def Parse(self, argument): if isinstance(argument, list): return argument elif argument == '': return [] else: return [s.strip() for s in argument.split(self._token)] def Type(self): return '%s separated list of strings' % self._name class ListParser(BaseListParser): """Parser for a comma-separated list of strings.""" def __init__(self): BaseListParser.__init__(self, ',', 'comma') def WriteCustomInfoInXMLFormat(self, outfile, indent): BaseListParser.WriteCustomInfoInXMLFormat(self, outfile, indent) _WriteSimpleXMLElement(outfile, 'list_separator', repr(','), indent) class WhitespaceSeparatedListParser(BaseListParser): """Parser for a whitespace-separated list of strings.""" def __init__(self): BaseListParser.__init__(self, None, 'whitespace') def WriteCustomInfoInXMLFormat(self, outfile, indent): BaseListParser.WriteCustomInfoInXMLFormat(self, outfile, indent) separators = list(string.whitespace) separators.sort() for ws_char in string.whitespace: _WriteSimpleXMLElement(outfile, 'list_separator', repr(ws_char), indent) def DEFINE_list(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value is a comma-separated list of strings.""" parser = ListParser() serializer = ListSerializer(',') DEFINE(parser, name, default, help, flag_values, serializer, **args) def DEFINE_spaceseplist(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value is a whitespace-separated list of strings. Any whitespace can be used as a separator. """ parser = WhitespaceSeparatedListParser() serializer = ListSerializer(' ') DEFINE(parser, name, default, help, flag_values, serializer, **args) # # MULTI FLAGS # class MultiFlag(Flag): """A flag that can appear multiple time on the command-line. The value of such a flag is a list that contains the individual values from all the appearances of that flag on the command-line. See the __doc__ for Flag for most behavior of this class. Only differences in behavior are described here: * The default value may be either a single value or a list of values. A single value is interpreted as the [value] singleton list. * The value of the flag is always a list, even if the option was only supplied once, and even if the default value is a single value """ def __init__(self, *args, **kwargs): Flag.__init__(self, *args, **kwargs) self.help += ';\n repeat this option to specify a list of values' def Parse(self, arguments): """Parses one or more arguments with the installed parser. Args: arguments: a single argument or a list of arguments (typically a list of default values); a single argument is converted internally into a list containing one item. """ if not isinstance(arguments, list): # Default value may be a list of values. Most other arguments # will not be, so convert them into a single-item list to make # processing simpler below. arguments = [arguments] if self.present: # keep a backup reference to list of previously supplied option values values = self.value else: # "erase" the defaults with an empty list values = [] for item in arguments: # have Flag superclass parse argument, overwriting self.value reference Flag.Parse(self, item) # also increments self.present values.append(self.value) # put list of option values back in the 'value' attribute self.value = values def Serialize(self): if not self.serializer: raise FlagsError("Serializer not present for flag %s" % self.name) if self.value is None: return '' s = '' multi_value = self.value for self.value in multi_value: if s: s += ' ' s += Flag.Serialize(self) self.value = multi_value return s def Type(self): return 'multi ' + self.parser.Type() def DEFINE_multi(parser, serializer, name, default, help, flag_values=FLAGS, **args): """Registers a generic MultiFlag that parses its args with a given parser. Auxiliary function. Normal users should NOT use it directly. Developers who need to create their own 'Parser' classes for options which can appear multiple times can call this module function to register their flags. """ DEFINE_flag(MultiFlag(parser, serializer, name, default, help, **args), flag_values) def DEFINE_multistring(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value can be a list of any strings. Use the flag on the command line multiple times to place multiple string values into the list. The 'default' may be a single string (which will be converted into a single-element list) or a list of strings. """ parser = ArgumentParser() serializer = ArgumentSerializer() DEFINE_multi(parser, serializer, name, default, help, flag_values, **args) def DEFINE_multi_int(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value can be a list of arbitrary integers. Use the flag on the command line multiple times to place multiple integer values into the list. The 'default' may be a single integer (which will be converted into a single-element list) or a list of integers. """ parser = IntegerParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE_multi(parser, serializer, name, default, help, flag_values, **args) # Now register the flags that we want to exist in all applications. # These are all defined with allow_override=1, so user-apps can use # these flagnames for their own purposes, if they want. DEFINE_flag(HelpFlag()) DEFINE_flag(HelpshortFlag()) DEFINE_flag(HelpXMLFlag()) # Define special flags here so that help may be generated for them. # NOTE: Please do NOT use _SPECIAL_FLAGS from outside this module. _SPECIAL_FLAGS = FlagValues() DEFINE_string( 'flagfile', "", "Insert flag definitions from the given file into the command line.", _SPECIAL_FLAGS) DEFINE_string( 'undefok', "", "comma-separated list of flag names that it is okay to specify " "on the command line even if the program does not define a flag " "with that name. IMPORTANT: flags in this list that have " "arguments MUST use the --flag=value format.", _SPECIAL_FLAGS)
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Simple command-line example for Latitude. Command-line application that sets the users current location. """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' import httplib2 from apiclient.discovery import build from oauth2client.file import Storage from oauth2client.client import OAuth2WebServerFlow from oauth2client.tools import run from apiclient.oauth import CredentialsInvalidError # Uncomment to get detailed logging #httplib2.debuglevel = 4 def main(): storage = Storage('latitude.dat') credentials = storage.get() if credentials is None or credentials.invalid: flow = OAuth2WebServerFlow( client_id='433807057907.apps.googleusercontent.com', client_secret='jigtZpMApkRxncxikFpR+SFg', scope='https://www.googleapis.com/auth/latitude', user_agent='latitude-cmdline-sample/1.0') credentials = run(flow, storage) http = httplib2.Http() http = credentials.authorize(http) service = build("latitude", "v1", http=http) body = { "data": { "kind": "latitude#location", "latitude": 37.420352, "longitude": -122.083389, "accuracy": 130, "altitude": 35 } } try: print service.currentLocation().insert(body=body).execute() except CredentialsInvalidError: print 'Your credentials are no longer valid.' print 'Please re-run this application to re-authorize.' if __name__ == '__main__': main()
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Simple command-line example for Latitude. Command-line application that sets the users current location. """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' import httplib2 from apiclient.discovery import build from oauth2client.file import Storage from oauth2client.client import OAuth2WebServerFlow from oauth2client.tools import run from apiclient.oauth import CredentialsInvalidError # Uncomment to get detailed logging #httplib2.debuglevel = 4 def main(): storage = Storage('latitude.dat') credentials = storage.get() if credentials is None or credentials.invalid: flow = OAuth2WebServerFlow( client_id='433807057907.apps.googleusercontent.com', client_secret='jigtZpMApkRxncxikFpR+SFg', scope='https://www.googleapis.com/auth/latitude', user_agent='latitude-cmdline-sample/1.0') credentials = run(flow, storage) http = httplib2.Http() http = credentials.authorize(http) service = build("latitude", "v1", http=http) body = { "data": { "kind": "latitude#location", "latitude": 37.420352, "longitude": -122.083389, "accuracy": 130, "altitude": 35 } } try: print service.currentLocation().insert(body=body).execute() except CredentialsInvalidError: print 'Your credentials are no longer valid.' print 'Please re-run this application to re-authorize.' if __name__ == '__main__': main()
Python
#!/usr/bin/env python # # Copyright 2007 Google Inc. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. # __author__ = 'jcgregorio@google.com (Joe Gregorio)' import httplib2 import logging import os import pickle from apiclient.discovery import build from oauth2client.appengine import CredentialsProperty from oauth2client.appengine import StorageByKeyName from oauth2client.client import OAuth2WebServerFlow from google.appengine.api import memcache from google.appengine.api import users from google.appengine.ext import db from google.appengine.ext import webapp from google.appengine.ext.webapp import template from google.appengine.ext.webapp import util from google.appengine.ext.webapp.util import login_required class Credentials(db.Model): credentials = CredentialsProperty() class MainHandler(webapp.RequestHandler): @login_required def get(self): user = users.get_current_user() credentials = StorageByKeyName( Credentials, user.user_id(), 'credentials').get() if credentials is None or credentials.invalid == True: flow = OAuth2WebServerFlow( # Visit https://code.google.com/apis/console to # generate your client_id, client_secret and to # register your redirect_uri. client_id='<YOUR CLIENT ID HERE>', client_secret='<YOUR CLIENT SECRET HERE>', scope='https://www.googleapis.com/auth/buzz', user_agent='buzz-cmdline-sample/1.0', domain='anonymous', xoauth_displayname='Google App Engine Example App') callback = self.request.relative_url('/auth_return') authorize_url = flow.step1_get_authorize_url(callback) memcache.set(user.user_id(), pickle.dumps(flow)) self.redirect(authorize_url) else: http = httplib2.Http() http = credentials.authorize(http) service = build("buzz", "v1", http=http) activities = service.activities() activitylist = activities.list(scope='@consumption', userId='@me').execute() path = os.path.join(os.path.dirname(__file__), 'welcome.html') logout = users.create_logout_url('/') self.response.out.write( template.render( path, {'activitylist': activitylist, 'logout': logout })) class OAuthHandler(webapp.RequestHandler): @login_required def get(self): user = users.get_current_user() flow = pickle.loads(memcache.get(user.user_id())) if flow: credentials = flow.step2_exchange(self.request.params) StorageByKeyName( Credentials, user.user_id(), 'credentials').put(credentials) self.redirect("/") else: pass def main(): application = webapp.WSGIApplication( [ ('/', MainHandler), ('/auth_return', OAuthHandler) ], debug=True) util.run_wsgi_app(application) if __name__ == '__main__': main()
Python
#!/usr/bin/env python # Copyright (c) 2010, Google Inc. # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. """Module to enforce different constraints on flags. A validator represents an invariant, enforced over a one or more flags. See 'FLAGS VALIDATORS' in flags.py's docstring for a usage manual. """ __author__ = 'olexiy@google.com (Olexiy Oryeshko)' class Error(Exception): """Thrown If validator constraint is not satisfied.""" class Validator(object): """Base class for flags validators. Users should NOT overload these classes, and use flags.Register... methods instead. """ # Used to assign each validator an unique insertion_index validators_count = 0 def __init__(self, checker, message): """Constructor to create all validators. Args: checker: function to verify the constraint. Input of this method varies, see SimpleValidator and DictionaryValidator for a detailed description. message: string, error message to be shown to the user """ self.checker = checker self.message = message Validator.validators_count += 1 # Used to assert validators in the order they were registered (CL/18694236) self.insertion_index = Validator.validators_count def Verify(self, flag_values): """Verify that constraint is satisfied. flags library calls this method to verify Validator's constraint. Args: flag_values: flags.FlagValues, containing all flags Raises: Error: if constraint is not satisfied. """ param = self._GetInputToCheckerFunction(flag_values) if not self.checker(param): raise Error(self.message) def GetFlagsNames(self): """Return the names of the flags checked by this validator. Returns: [string], names of the flags """ raise NotImplementedError('This method should be overloaded') def PrintFlagsWithValues(self, flag_values): raise NotImplementedError('This method should be overloaded') def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues, containing all flags. Returns: Return type depends on the specific validator. """ raise NotImplementedError('This method should be overloaded') class SimpleValidator(Validator): """Validator behind RegisterValidator() method. Validates that a single flag passes its checker function. The checker function takes the flag value and returns True (if value looks fine) or, if flag value is not valid, either returns False or raises an Exception.""" def __init__(self, flag_name, checker, message): """Constructor. Args: flag_name: string, name of the flag. checker: function to verify the validator. input - value of the corresponding flag (string, boolean, etc). output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise Error. message: string, error message to be shown to the user if validator's condition is not satisfied """ super(SimpleValidator, self).__init__(checker, message) self.flag_name = flag_name def GetFlagsNames(self): return [self.flag_name] def PrintFlagsWithValues(self, flag_values): return 'flag --%s=%s' % (self.flag_name, flag_values[self.flag_name].value) def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues Returns: value of the corresponding flag. """ return flag_values[self.flag_name].value class DictionaryValidator(Validator): """Validator behind RegisterDictionaryValidator method. Validates that flag values pass their common checker function. The checker function takes flag values and returns True (if values look fine) or, if values are not valid, either returns False or raises an Exception. """ def __init__(self, flag_names, checker, message): """Constructor. Args: flag_names: [string], containing names of the flags used by checker. checker: function to verify the validator. input - dictionary, with keys() being flag_names, and value for each key being the value of the corresponding flag (string, boolean, etc). output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise Error. message: string, error message to be shown to the user if validator's condition is not satisfied """ super(DictionaryValidator, self).__init__(checker, message) self.flag_names = flag_names def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues Returns: dictionary, with keys() being self.lag_names, and value for each key being the value of the corresponding flag (string, boolean, etc). """ return dict([key, flag_values[key].value] for key in self.flag_names) def PrintFlagsWithValues(self, flag_values): prefix = 'flags ' flags_with_values = [] for key in self.flag_names: flags_with_values.append('%s=%s' % (key, flag_values[key].value)) return prefix + ', '.join(flags_with_values) def GetFlagsNames(self): return self.flag_names
Python
#!/usr/bin/env python # # Copyright 2007 Google Inc. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. # __author__ = 'jcgregorio@google.com (Joe Gregorio)' import httplib2 import logging import os import pickle from apiclient.discovery import build from oauth2client.appengine import CredentialsProperty from oauth2client.appengine import StorageByKeyName from oauth2client.client import OAuth2WebServerFlow from google.appengine.api import memcache from google.appengine.api import users from google.appengine.ext import db from google.appengine.ext import webapp from google.appengine.ext.webapp import template from google.appengine.ext.webapp import util from google.appengine.ext.webapp.util import login_required class Credentials(db.Model): credentials = CredentialsProperty() class MainHandler(webapp.RequestHandler): @login_required def get(self): user = users.get_current_user() credentials = StorageByKeyName( Credentials, user.user_id(), 'credentials').get() if credentials is None or credentials.invalid == True: flow = OAuth2WebServerFlow( # Visit https://code.google.com/apis/console to # generate your client_id, client_secret and to # register your redirect_uri. client_id='<YOUR CLIENT ID HERE>', client_secret='<YOUR CLIENT SECRET HERE>', scope='https://www.googleapis.com/auth/buzz', user_agent='buzz-cmdline-sample/1.0', domain='anonymous', xoauth_displayname='Google App Engine Example App') callback = self.request.relative_url('/auth_return') authorize_url = flow.step1_get_authorize_url(callback) memcache.set(user.user_id(), pickle.dumps(flow)) self.redirect(authorize_url) else: http = httplib2.Http() http = credentials.authorize(http) service = build("buzz", "v1", http=http) activities = service.activities() activitylist = activities.list(scope='@consumption', userId='@me').execute() path = os.path.join(os.path.dirname(__file__), 'welcome.html') logout = users.create_logout_url('/') self.response.out.write( template.render( path, {'activitylist': activitylist, 'logout': logout })) class OAuthHandler(webapp.RequestHandler): @login_required def get(self): user = users.get_current_user() flow = pickle.loads(memcache.get(user.user_id())) if flow: credentials = flow.step2_exchange(self.request.params) StorageByKeyName( Credentials, user.user_id(), 'credentials').put(credentials) self.redirect("/") else: pass def main(): application = webapp.WSGIApplication( [ ('/', MainHandler), ('/auth_return', OAuthHandler) ], debug=True) util.run_wsgi_app(application) if __name__ == '__main__': main()
Python
#!/usr/bin/env python # Copyright (c) 2007, Google Inc. # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. # # --- # Author: Chad Lester # Design and style contributions by: # Amit Patel, Bogdan Cocosel, Daniel Dulitz, Eric Tiedemann, # Eric Veach, Laurence Gonsalves, Matthew Springer # Code reorganized a bit by Craig Silverstein """This module is used to define and parse command line flags. This module defines a *distributed* flag-definition policy: rather than an application having to define all flags in or near main(), each python module defines flags that are useful to it. When one python module imports another, it gains access to the other's flags. (This is implemented by having all modules share a common, global registry object containing all the flag information.) Flags are defined through the use of one of the DEFINE_xxx functions. The specific function used determines how the flag is parsed, checked, and optionally type-converted, when it's seen on the command line. IMPLEMENTATION: DEFINE_* creates a 'Flag' object and registers it with a 'FlagValues' object (typically the global FlagValues FLAGS, defined here). The 'FlagValues' object can scan the command line arguments and pass flag arguments to the corresponding 'Flag' objects for value-checking and type conversion. The converted flag values are available as attributes of the 'FlagValues' object. Code can access the flag through a FlagValues object, for instance gflags.FLAGS.myflag. Typically, the __main__ module passes the command line arguments to gflags.FLAGS for parsing. At bottom, this module calls getopt(), so getopt functionality is supported, including short- and long-style flags, and the use of -- to terminate flags. Methods defined by the flag module will throw 'FlagsError' exceptions. The exception argument will be a human-readable string. FLAG TYPES: This is a list of the DEFINE_*'s that you can do. All flags take a name, default value, help-string, and optional 'short' name (one-letter name). Some flags have other arguments, which are described with the flag. DEFINE_string: takes any input, and interprets it as a string. DEFINE_bool or DEFINE_boolean: typically does not take an argument: say --myflag to set FLAGS.myflag to true, or --nomyflag to set FLAGS.myflag to false. Alternately, you can say --myflag=true or --myflag=t or --myflag=1 or --myflag=false or --myflag=f or --myflag=0 DEFINE_float: takes an input and interprets it as a floating point number. Takes optional args lower_bound and upper_bound; if the number specified on the command line is out of range, it will raise a FlagError. DEFINE_integer: takes an input and interprets it as an integer. Takes optional args lower_bound and upper_bound as for floats. DEFINE_enum: takes a list of strings which represents legal values. If the command-line value is not in this list, raise a flag error. Otherwise, assign to FLAGS.flag as a string. DEFINE_list: Takes a comma-separated list of strings on the commandline. Stores them in a python list object. DEFINE_spaceseplist: Takes a space-separated list of strings on the commandline. Stores them in a python list object. Example: --myspacesepflag "foo bar baz" DEFINE_multistring: The same as DEFINE_string, except the flag can be specified more than once on the commandline. The result is a python list object (list of strings), even if the flag is only on the command line once. DEFINE_multi_int: The same as DEFINE_integer, except the flag can be specified more than once on the commandline. The result is a python list object (list of ints), even if the flag is only on the command line once. SPECIAL FLAGS: There are a few flags that have special meaning: --help prints a list of all the flags in a human-readable fashion --helpshort prints a list of all key flags (see below). --helpxml prints a list of all flags, in XML format. DO NOT parse the output of --help and --helpshort. Instead, parse the output of --helpxml. For more info, see "OUTPUT FOR --helpxml" below. --flagfile=foo read flags from file foo. --undefok=f1,f2 ignore unrecognized option errors for f1,f2. For boolean flags, you should use --undefok=boolflag, and --boolflag and --noboolflag will be accepted. Do not use --undefok=noboolflag. -- as in getopt(), terminates flag-processing FLAGS VALIDATORS: If your program: - requires flag X to be specified - needs flag Y to match a regular expression - or requires any more general constraint to be satisfied then validators are for you! Each validator represents a constraint over one flag, which is enforced starting from the initial parsing of the flags and until the program terminates. Also, lower_bound and upper_bound for numerical flags are enforced using flag validators. Howto: If you want to enforce a constraint over one flag, use flags.RegisterValidator(flag_name, checker, message='Flag validation failed', flag_values=FLAGS) After flag values are initially parsed, and after any change to the specified flag, method checker(flag_value) will be executed. If constraint is not satisfied, an IllegalFlagValue exception will be raised. See RegisterValidator's docstring for a detailed explanation on how to construct your own checker. EXAMPLE USAGE: FLAGS = flags.FLAGS flags.DEFINE_integer('my_version', 0, 'Version number.') flags.DEFINE_string('filename', None, 'Input file name', short_name='f') flags.RegisterValidator('my_version', lambda value: value % 2 == 0, message='--my_version must be divisible by 2') flags.MarkFlagAsRequired('filename') NOTE ON --flagfile: Flags may be loaded from text files in addition to being specified on the commandline. Any flags you don't feel like typing, throw them in a file, one flag per line, for instance: --myflag=myvalue --nomyboolean_flag You then specify your file with the special flag '--flagfile=somefile'. You CAN recursively nest flagfile= tokens OR use multiple files on the command line. Lines beginning with a single hash '#' or a double slash '//' are comments in your flagfile. Any flagfile=<file> will be interpreted as having a relative path from the current working directory rather than from the place the file was included from: myPythonScript.py --flagfile=config/somefile.cfg If somefile.cfg includes further --flagfile= directives, these will be referenced relative to the original CWD, not from the directory the including flagfile was found in! The caveat applies to people who are including a series of nested files in a different dir than they are executing out of. Relative path names are always from CWD, not from the directory of the parent include flagfile. We do now support '~' expanded directory names. Absolute path names ALWAYS work! EXAMPLE USAGE: import gflags FLAGS = gflags.FLAGS # Flag names are globally defined! So in general, we need to be # careful to pick names that are unlikely to be used by other libraries. # If there is a conflict, we'll get an error at import time. gflags.DEFINE_string('name', 'Mr. President', 'your name') gflags.DEFINE_integer('age', None, 'your age in years', lower_bound=0) gflags.DEFINE_boolean('debug', False, 'produces debugging output') gflags.DEFINE_enum('gender', 'male', ['male', 'female'], 'your gender') def main(argv): try: argv = FLAGS(argv) # parse flags except gflags.FlagsError, e: print '%s\\nUsage: %s ARGS\\n%s' % (e, sys.argv[0], FLAGS) sys.exit(1) if FLAGS.debug: print 'non-flag arguments:', argv print 'Happy Birthday', FLAGS.name if FLAGS.age is not None: print 'You are a %s, who is %d years old' % (FLAGS.gender, FLAGS.age) if __name__ == '__main__': main(sys.argv) KEY FLAGS: As we already explained, each module gains access to all flags defined by all the other modules it transitively imports. In the case of non-trivial scripts, this means a lot of flags ... For documentation purposes, it is good to identify the flags that are key (i.e., really important) to a module. Clearly, the concept of "key flag" is a subjective one. When trying to determine whether a flag is key to a module or not, assume that you are trying to explain your module to a potential user: which flags would you really like to mention first? We'll describe shortly how to declare which flags are key to a module. For the moment, assume we know the set of key flags for each module. Then, if you use the app.py module, you can use the --helpshort flag to print only the help for the flags that are key to the main module, in a human-readable format. NOTE: If you need to parse the flag help, do NOT use the output of --help / --helpshort. That output is meant for human consumption, and may be changed in the future. Instead, use --helpxml; flags that are key for the main module are marked there with a <key>yes</key> element. The set of key flags for a module M is composed of: 1. Flags defined by module M by calling a DEFINE_* function. 2. Flags that module M explictly declares as key by using the function DECLARE_key_flag(<flag_name>) 3. Key flags of other modules that M specifies by using the function ADOPT_module_key_flags(<other_module>) This is a "bulk" declaration of key flags: each flag that is key for <other_module> becomes key for the current module too. Notice that if you do not use the functions described at points 2 and 3 above, then --helpshort prints information only about the flags defined by the main module of our script. In many cases, this behavior is good enough. But if you move part of the main module code (together with the related flags) into a different module, then it is nice to use DECLARE_key_flag / ADOPT_module_key_flags and make sure --helpshort lists all relevant flags (otherwise, your code refactoring may confuse your users). Note: each of DECLARE_key_flag / ADOPT_module_key_flags has its own pluses and minuses: DECLARE_key_flag is more targeted and may lead a more focused --helpshort documentation. ADOPT_module_key_flags is good for cases when an entire module is considered key to the current script. Also, it does not require updates to client scripts when a new flag is added to the module. EXAMPLE USAGE 2 (WITH KEY FLAGS): Consider an application that contains the following three files (two auxiliary modules and a main module): File libfoo.py: import gflags gflags.DEFINE_integer('num_replicas', 3, 'Number of replicas to start') gflags.DEFINE_boolean('rpc2', True, 'Turn on the usage of RPC2.') ... some code ... File libbar.py: import gflags gflags.DEFINE_string('bar_gfs_path', '/gfs/path', 'Path to the GFS files for libbar.') gflags.DEFINE_string('email_for_bar_errors', 'bar-team@google.com', 'Email address for bug reports about module libbar.') gflags.DEFINE_boolean('bar_risky_hack', False, 'Turn on an experimental and buggy optimization.') ... some code ... File myscript.py: import gflags import libfoo import libbar gflags.DEFINE_integer('num_iterations', 0, 'Number of iterations.') # Declare that all flags that are key for libfoo are # key for this module too. gflags.ADOPT_module_key_flags(libfoo) # Declare that the flag --bar_gfs_path (defined in libbar) is key # for this module. gflags.DECLARE_key_flag('bar_gfs_path') ... some code ... When myscript is invoked with the flag --helpshort, the resulted help message lists information about all the key flags for myscript: --num_iterations, --num_replicas, --rpc2, and --bar_gfs_path (in addition to the special flags --help and --helpshort). Of course, myscript uses all the flags declared by it (in this case, just --num_replicas) or by any of the modules it transitively imports (e.g., the modules libfoo, libbar). E.g., it can access the value of FLAGS.bar_risky_hack, even if --bar_risky_hack is not declared as a key flag for myscript. OUTPUT FOR --helpxml: The --helpxml flag generates output with the following structure: <?xml version="1.0"?> <AllFlags> <program>PROGRAM_BASENAME</program> <usage>MAIN_MODULE_DOCSTRING</usage> (<flag> [<key>yes</key>] <file>DECLARING_MODULE</file> <name>FLAG_NAME</name> <meaning>FLAG_HELP_MESSAGE</meaning> <default>DEFAULT_FLAG_VALUE</default> <current>CURRENT_FLAG_VALUE</current> <type>FLAG_TYPE</type> [OPTIONAL_ELEMENTS] </flag>)* </AllFlags> Notes: 1. The output is intentionally similar to the output generated by the C++ command-line flag library. The few differences are due to the Python flags that do not have a C++ equivalent (at least not yet), e.g., DEFINE_list. 2. New XML elements may be added in the future. 3. DEFAULT_FLAG_VALUE is in serialized form, i.e., the string you can pass for this flag on the command-line. E.g., for a flag defined using DEFINE_list, this field may be foo,bar, not ['foo', 'bar']. 4. CURRENT_FLAG_VALUE is produced using str(). This means that the string 'false' will be represented in the same way as the boolean False. Using repr() would have removed this ambiguity and simplified parsing, but would have broken the compatibility with the C++ command-line flags. 5. OPTIONAL_ELEMENTS describe elements relevant for certain kinds of flags: lower_bound, upper_bound (for flags that specify bounds), enum_value (for enum flags), list_separator (for flags that consist of a list of values, separated by a special token). 6. We do not provide any example here: please use --helpxml instead. """ import cgi import getopt import os import re import string import sys import gflags_validators # Are we running at least python 2.2? try: if tuple(sys.version_info[:3]) < (2,2,0): raise NotImplementedError("requires python 2.2.0 or later") except AttributeError: # a very old python, that lacks sys.version_info raise NotImplementedError("requires python 2.2.0 or later") # If we're not running at least python 2.2.1, define True, False, and bool. # Thanks, Guido, for the code. try: True, False, bool except NameError: False = 0 True = 1 def bool(x): if x: return True else: return False # Are we running under pychecker? _RUNNING_PYCHECKER = 'pychecker.python' in sys.modules def _GetCallingModule(): """Returns the name of the module that's calling into this module. We generally use this function to get the name of the module calling a DEFINE_foo... function. """ # Walk down the stack to find the first globals dict that's not ours. for depth in range(1, sys.getrecursionlimit()): if not sys._getframe(depth).f_globals is globals(): globals_for_frame = sys._getframe(depth).f_globals module_name = _GetModuleObjectAndName(globals_for_frame)[1] if module_name is not None: return module_name raise AssertionError("No module was found") def _GetThisModuleObjectAndName(): """Returns: (module object, module name) for this module.""" return _GetModuleObjectAndName(globals()) # module exceptions: class FlagsError(Exception): """The base class for all flags errors.""" pass class DuplicateFlag(FlagsError): """Raised if there is a flag naming conflict.""" pass class DuplicateFlagCannotPropagateNoneToSwig(DuplicateFlag): """Special case of DuplicateFlag -- SWIG flag value can't be set to None. This can be raised when a duplicate flag is created. Even if allow_override is True, we still abort if the new value is None, because it's currently impossible to pass None default value back to SWIG. See FlagValues.SetDefault for details. """ pass # A DuplicateFlagError conveys more information than a # DuplicateFlag. Since there are external modules that create # DuplicateFlags, the interface to DuplicateFlag shouldn't change. class DuplicateFlagError(DuplicateFlag): def __init__(self, flagname, flag_values): self.flagname = flagname message = "The flag '%s' is defined twice." % self.flagname flags_by_module = flag_values.FlagsByModuleDict() for module in flags_by_module: for flag in flags_by_module[module]: if flag.name == flagname or flag.short_name == flagname: message = message + " First from " + module + "," break message = message + " Second from " + _GetCallingModule() DuplicateFlag.__init__(self, message) class IllegalFlagValue(FlagsError): """The flag command line argument is illegal.""" pass class UnrecognizedFlag(FlagsError): """Raised if a flag is unrecognized.""" pass # An UnrecognizedFlagError conveys more information than an UnrecognizedFlag. # Since there are external modules that create DuplicateFlags, the interface to # DuplicateFlag shouldn't change. The flagvalue will be assigned the full value # of the flag and its argument, if any, allowing handling of unrecognzed flags # in an exception handler. # If flagvalue is the empty string, then this exception is an due to a # reference to a flag that was not already defined. class UnrecognizedFlagError(UnrecognizedFlag): def __init__(self, flagname, flagvalue=''): self.flagname = flagname self.flagvalue = flagvalue UnrecognizedFlag.__init__( self, "Unknown command line flag '%s'" % flagname) # Global variable used by expvar _exported_flags = {} _help_width = 80 # width of help output def GetHelpWidth(): """Returns: an integer, the width of help lines that is used in TextWrap.""" return _help_width def CutCommonSpacePrefix(text): """Removes a common space prefix from the lines of a multiline text. If the first line does not start with a space, it is left as it is and only in the remaining lines a common space prefix is being searched for. That means the first line will stay untouched. This is especially useful to turn doc strings into help texts. This is because some people prefer to have the doc comment start already after the apostrophy and then align the following lines while others have the apostrophies on a seperately line. The function also drops trailing empty lines and ignores empty lines following the initial content line while calculating the initial common whitespace. Args: text: text to work on Returns: the resulting text """ text_lines = text.splitlines() # Drop trailing empty lines while text_lines and not text_lines[-1]: text_lines = text_lines[:-1] if text_lines: # We got some content, is the first line starting with a space? if text_lines[0] and text_lines[0][0].isspace(): text_first_line = [] else: text_first_line = [text_lines.pop(0)] # Calculate length of common leading whitesppace (only over content lines) common_prefix = os.path.commonprefix([line for line in text_lines if line]) space_prefix_len = len(common_prefix) - len(common_prefix.lstrip()) # If we have a common space prefix, drop it from all lines if space_prefix_len: for index in xrange(len(text_lines)): if text_lines[index]: text_lines[index] = text_lines[index][space_prefix_len:] return '\n'.join(text_first_line + text_lines) return '' def TextWrap(text, length=None, indent='', firstline_indent=None, tabs=' '): """Wraps a given text to a maximum line length and returns it. We turn lines that only contain whitespaces into empty lines. We keep new lines and tabs (e.g., we do not treat tabs as spaces). Args: text: text to wrap length: maximum length of a line, includes indentation if this is None then use GetHelpWidth() indent: indent for all but first line firstline_indent: indent for first line; if None, fall back to indent tabs: replacement for tabs Returns: wrapped text Raises: FlagsError: if indent not shorter than length FlagsError: if firstline_indent not shorter than length """ # Get defaults where callee used None if length is None: length = GetHelpWidth() if indent is None: indent = '' if len(indent) >= length: raise FlagsError('Indent must be shorter than length') # In line we will be holding the current line which is to be started # with indent (or firstline_indent if available) and then appended # with words. if firstline_indent is None: firstline_indent = '' line = indent else: line = firstline_indent if len(firstline_indent) >= length: raise FlagsError('First iline indent must be shorter than length') # If the callee does not care about tabs we simply convert them to # spaces If callee wanted tabs to be single space then we do that # already here. if not tabs or tabs == ' ': text = text.replace('\t', ' ') else: tabs_are_whitespace = not tabs.strip() line_regex = re.compile('([ ]*)(\t*)([^ \t]+)', re.MULTILINE) # Split the text into lines and the lines with the regex above. The # resulting lines are collected in result[]. For each split we get the # spaces, the tabs and the next non white space (e.g. next word). result = [] for text_line in text.splitlines(): # Store result length so we can find out whether processing the next # line gave any new content old_result_len = len(result) # Process next line with line_regex. For optimization we do an rstrip(). # - process tabs (changes either line or word, see below) # - process word (first try to squeeze on line, then wrap or force wrap) # Spaces found on the line are ignored, they get added while wrapping as # needed. for spaces, current_tabs, word in line_regex.findall(text_line.rstrip()): # If tabs weren't converted to spaces, handle them now if current_tabs: # If the last thing we added was a space anyway then drop # it. But let's not get rid of the indentation. if (((result and line != indent) or (not result and line != firstline_indent)) and line[-1] == ' '): line = line[:-1] # Add the tabs, if that means adding whitespace, just add it at # the line, the rstrip() code while shorten the line down if # necessary if tabs_are_whitespace: line += tabs * len(current_tabs) else: # if not all tab replacement is whitespace we prepend it to the word word = tabs * len(current_tabs) + word # Handle the case where word cannot be squeezed onto current last line if len(line) + len(word) > length and len(indent) + len(word) <= length: result.append(line.rstrip()) line = indent + word word = '' # No space left on line or can we append a space? if len(line) + 1 >= length: result.append(line.rstrip()) line = indent else: line += ' ' # Add word and shorten it up to allowed line length. Restart next # line with indent and repeat, or add a space if we're done (word # finished) This deals with words that caanot fit on one line # (e.g. indent + word longer than allowed line length). while len(line) + len(word) >= length: line += word result.append(line[:length]) word = line[length:] line = indent # Default case, simply append the word and a space if word: line += word + ' ' # End of input line. If we have content we finish the line. If the # current line is just the indent but we had content in during this # original line then we need to add an emoty line. if (result and line != indent) or (not result and line != firstline_indent): result.append(line.rstrip()) elif len(result) == old_result_len: result.append('') line = indent return '\n'.join(result) def DocToHelp(doc): """Takes a __doc__ string and reformats it as help.""" # Get rid of starting and ending white space. Using lstrip() or even # strip() could drop more than maximum of first line and right space # of last line. doc = doc.strip() # Get rid of all empty lines whitespace_only_line = re.compile('^[ \t]+$', re.M) doc = whitespace_only_line.sub('', doc) # Cut out common space at line beginnings doc = CutCommonSpacePrefix(doc) # Just like this module's comment, comments tend to be aligned somehow. # In other words they all start with the same amount of white space # 1) keep double new lines # 2) keep ws after new lines if not empty line # 3) all other new lines shall be changed to a space # Solution: Match new lines between non white space and replace with space. doc = re.sub('(?<=\S)\n(?=\S)', ' ', doc, re.M) return doc def _GetModuleObjectAndName(globals_dict): """Returns the module that defines a global environment, and its name. Args: globals_dict: A dictionary that should correspond to an environment providing the values of the globals. Returns: A pair consisting of (1) module object and (2) module name (a string). Returns (None, None) if the module could not be identified. """ # The use of .items() (instead of .iteritems()) is NOT a mistake: if # a parallel thread imports a module while we iterate over # .iteritems() (not nice, but possible), we get a RuntimeError ... # Hence, we use the slightly slower but safer .items(). for name, module in sys.modules.items(): if getattr(module, '__dict__', None) is globals_dict: if name == '__main__': # Pick a more informative name for the main module. name = sys.argv[0] return (module, name) return (None, None) def _GetMainModule(): """Returns the name of the module from which execution started.""" for depth in range(1, sys.getrecursionlimit()): try: globals_of_main = sys._getframe(depth).f_globals except ValueError: return _GetModuleObjectAndName(globals_of_main)[1] raise AssertionError("No module was found") class FlagValues: """Registry of 'Flag' objects. A 'FlagValues' can then scan command line arguments, passing flag arguments through to the 'Flag' objects that it owns. It also provides easy access to the flag values. Typically only one 'FlagValues' object is needed by an application: gflags.FLAGS This class is heavily overloaded: 'Flag' objects are registered via __setitem__: FLAGS['longname'] = x # register a new flag The .value attribute of the registered 'Flag' objects can be accessed as attributes of this 'FlagValues' object, through __getattr__. Both the long and short name of the original 'Flag' objects can be used to access its value: FLAGS.longname # parsed flag value FLAGS.x # parsed flag value (short name) Command line arguments are scanned and passed to the registered 'Flag' objects through the __call__ method. Unparsed arguments, including argv[0] (e.g. the program name) are returned. argv = FLAGS(sys.argv) # scan command line arguments The original registered Flag objects can be retrieved through the use of the dictionary-like operator, __getitem__: x = FLAGS['longname'] # access the registered Flag object The str() operator of a 'FlagValues' object provides help for all of the registered 'Flag' objects. """ def __init__(self): # Since everything in this class is so heavily overloaded, the only # way of defining and using fields is to access __dict__ directly. # Dictionary: flag name (string) -> Flag object. self.__dict__['__flags'] = {} # Dictionary: module name (string) -> list of Flag objects that are defined # by that module. self.__dict__['__flags_by_module'] = {} # Dictionary: module name (string) -> list of Flag objects that are # key for that module. self.__dict__['__key_flags_by_module'] = {} # Set if we should use new style gnu_getopt rather than getopt when parsing # the args. Only possible with Python 2.3+ self.UseGnuGetOpt(False) def UseGnuGetOpt(self, use_gnu_getopt=True): self.__dict__['__use_gnu_getopt'] = use_gnu_getopt def IsGnuGetOpt(self): return self.__dict__['__use_gnu_getopt'] def FlagDict(self): return self.__dict__['__flags'] def FlagsByModuleDict(self): """Returns the dictionary of module_name -> list of defined flags. Returns: A dictionary. Its keys are module names (strings). Its values are lists of Flag objects. """ return self.__dict__['__flags_by_module'] def KeyFlagsByModuleDict(self): """Returns the dictionary of module_name -> list of key flags. Returns: A dictionary. Its keys are module names (strings). Its values are lists of Flag objects. """ return self.__dict__['__key_flags_by_module'] def _RegisterFlagByModule(self, module_name, flag): """Records the module that defines a specific flag. We keep track of which flag is defined by which module so that we can later sort the flags by module. Args: module_name: A string, the name of a Python module. flag: A Flag object, a flag that is key to the module. """ flags_by_module = self.FlagsByModuleDict() flags_by_module.setdefault(module_name, []).append(flag) def _RegisterKeyFlagForModule(self, module_name, flag): """Specifies that a flag is a key flag for a module. Args: module_name: A string, the name of a Python module. flag: A Flag object, a flag that is key to the module. """ key_flags_by_module = self.KeyFlagsByModuleDict() # The list of key flags for the module named module_name. key_flags = key_flags_by_module.setdefault(module_name, []) # Add flag, but avoid duplicates. if flag not in key_flags: key_flags.append(flag) def _GetFlagsDefinedByModule(self, module): """Returns the list of flags defined by a module. Args: module: A module object or a module name (a string). Returns: A new list of Flag objects. Caller may update this list as he wishes: none of those changes will affect the internals of this FlagValue object. """ if not isinstance(module, str): module = module.__name__ return list(self.FlagsByModuleDict().get(module, [])) def _GetKeyFlagsForModule(self, module): """Returns the list of key flags for a module. Args: module: A module object or a module name (a string) Returns: A new list of Flag objects. Caller may update this list as he wishes: none of those changes will affect the internals of this FlagValue object. """ if not isinstance(module, str): module = module.__name__ # Any flag is a key flag for the module that defined it. NOTE: # key_flags is a fresh list: we can update it without affecting the # internals of this FlagValues object. key_flags = self._GetFlagsDefinedByModule(module) # Take into account flags explicitly declared as key for a module. for flag in self.KeyFlagsByModuleDict().get(module, []): if flag not in key_flags: key_flags.append(flag) return key_flags def AppendFlagValues(self, flag_values): """Appends flags registered in another FlagValues instance. Args: flag_values: registry to copy from """ for flag_name, flag in flag_values.FlagDict().iteritems(): # Each flags with shortname appears here twice (once under its # normal name, and again with its short name). To prevent # problems (DuplicateFlagError) with double flag registration, we # perform a check to make sure that the entry we're looking at is # for its normal name. if flag_name == flag.name: self[flag_name] = flag def RemoveFlagValues(self, flag_values): """Remove flags that were previously appended from another FlagValues. Args: flag_values: registry containing flags to remove. """ for flag_name in flag_values.FlagDict(): self.__delattr__(flag_name) def __setitem__(self, name, flag): """Registers a new flag variable.""" fl = self.FlagDict() if not isinstance(flag, Flag): raise IllegalFlagValue(flag) if not isinstance(name, type("")): raise FlagsError("Flag name must be a string") if len(name) == 0: raise FlagsError("Flag name cannot be empty") # If running under pychecker, duplicate keys are likely to be # defined. Disable check for duplicate keys when pycheck'ing. if (fl.has_key(name) and not flag.allow_override and not fl[name].allow_override and not _RUNNING_PYCHECKER): raise DuplicateFlagError(name, self) short_name = flag.short_name if short_name is not None: if (fl.has_key(short_name) and not flag.allow_override and not fl[short_name].allow_override and not _RUNNING_PYCHECKER): raise DuplicateFlagError(short_name, self) fl[short_name] = flag fl[name] = flag global _exported_flags _exported_flags[name] = flag def __getitem__(self, name): """Retrieves the Flag object for the flag --name.""" return self.FlagDict()[name] def __getattr__(self, name): """Retrieves the 'value' attribute of the flag --name.""" fl = self.FlagDict() if not fl.has_key(name): raise AttributeError(name) return fl[name].value def __setattr__(self, name, value): """Sets the 'value' attribute of the flag --name.""" fl = self.FlagDict() fl[name].value = value self._AssertValidators(fl[name].validators) return value def _AssertAllValidators(self): all_validators = set() for flag in self.FlagDict().itervalues(): for validator in flag.validators: all_validators.add(validator) self._AssertValidators(all_validators) def _AssertValidators(self, validators): """Assert if all validators in the list are satisfied. Asserts validators in the order they were created. Args: validators: Iterable(gflags_validators.Validator), validators to be verified Raises: AttributeError: if validators work with a non-existing flag. IllegalFlagValue: if validation fails for at least one validator """ for validator in sorted( validators, key=lambda validator: validator.insertion_index): try: validator.Verify(self) except gflags_validators.Error, e: message = validator.PrintFlagsWithValues(self) raise IllegalFlagValue('%s: %s' % (message, str(e))) def _FlagIsRegistered(self, flag_obj): """Checks whether a Flag object is registered under some name. Note: this is non trivial: in addition to its normal name, a flag may have a short name too. In self.FlagDict(), both the normal and the short name are mapped to the same flag object. E.g., calling only "del FLAGS.short_name" is not unregistering the corresponding Flag object (it is still registered under the longer name). Args: flag_obj: A Flag object. Returns: A boolean: True iff flag_obj is registered under some name. """ flag_dict = self.FlagDict() # Check whether flag_obj is registered under its long name. name = flag_obj.name if flag_dict.get(name, None) == flag_obj: return True # Check whether flag_obj is registered under its short name. short_name = flag_obj.short_name if (short_name is not None and flag_dict.get(short_name, None) == flag_obj): return True # The flag cannot be registered under any other name, so we do not # need to do a full search through the values of self.FlagDict(). return False def __delattr__(self, flag_name): """Deletes a previously-defined flag from a flag object. This method makes sure we can delete a flag by using del flag_values_object.<flag_name> E.g., flags.DEFINE_integer('foo', 1, 'Integer flag.') del flags.FLAGS.foo Args: flag_name: A string, the name of the flag to be deleted. Raises: AttributeError: When there is no registered flag named flag_name. """ fl = self.FlagDict() if flag_name not in fl: raise AttributeError(flag_name) flag_obj = fl[flag_name] del fl[flag_name] if not self._FlagIsRegistered(flag_obj): # If the Flag object indicated by flag_name is no longer # registered (please see the docstring of _FlagIsRegistered), then # we delete the occurences of the flag object in all our internal # dictionaries. self.__RemoveFlagFromDictByModule(self.FlagsByModuleDict(), flag_obj) self.__RemoveFlagFromDictByModule(self.KeyFlagsByModuleDict(), flag_obj) def __RemoveFlagFromDictByModule(self, flags_by_module_dict, flag_obj): """Removes a flag object from a module -> list of flags dictionary. Args: flags_by_module_dict: A dictionary that maps module names to lists of flags. flag_obj: A flag object. """ for unused_module, flags_in_module in flags_by_module_dict.iteritems(): # while (as opposed to if) takes care of multiple occurences of a # flag in the list for the same module. while flag_obj in flags_in_module: flags_in_module.remove(flag_obj) def SetDefault(self, name, value): """Changes the default value of the named flag object.""" fl = self.FlagDict() if not fl.has_key(name): raise AttributeError(name) fl[name].SetDefault(value) self._AssertValidators(fl[name].validators) def __contains__(self, name): """Returns True if name is a value (flag) in the dict.""" return name in self.FlagDict() has_key = __contains__ # a synonym for __contains__() def __iter__(self): return self.FlagDict().iterkeys() def __call__(self, argv): """Parses flags from argv; stores parsed flags into this FlagValues object. All unparsed arguments are returned. Flags are parsed using the GNU Program Argument Syntax Conventions, using getopt: http://www.gnu.org/software/libc/manual/html_mono/libc.html#Getopt Args: argv: argument list. Can be of any type that may be converted to a list. Returns: The list of arguments not parsed as options, including argv[0] Raises: FlagsError: on any parsing error """ # Support any sequence type that can be converted to a list argv = list(argv) shortopts = "" longopts = [] fl = self.FlagDict() # This pre parses the argv list for --flagfile=<> options. argv = argv[:1] + self.ReadFlagsFromFiles(argv[1:], force_gnu=False) # Correct the argv to support the google style of passing boolean # parameters. Boolean parameters may be passed by using --mybool, # --nomybool, --mybool=(true|false|1|0). getopt does not support # having options that may or may not have a parameter. We replace # instances of the short form --mybool and --nomybool with their # full forms: --mybool=(true|false). original_argv = list(argv) # list() makes a copy shortest_matches = None for name, flag in fl.items(): if not flag.boolean: continue if shortest_matches is None: # Determine the smallest allowable prefix for all flag names shortest_matches = self.ShortestUniquePrefixes(fl) no_name = 'no' + name prefix = shortest_matches[name] no_prefix = shortest_matches[no_name] # Replace all occurences of this boolean with extended forms for arg_idx in range(1, len(argv)): arg = argv[arg_idx] if arg.find('=') >= 0: continue if arg.startswith('--'+prefix) and ('--'+name).startswith(arg): argv[arg_idx] = ('--%s=true' % name) elif arg.startswith('--'+no_prefix) and ('--'+no_name).startswith(arg): argv[arg_idx] = ('--%s=false' % name) # Loop over all of the flags, building up the lists of short options # and long options that will be passed to getopt. Short options are # specified as a string of letters, each letter followed by a colon # if it takes an argument. Long options are stored in an array of # strings. Each string ends with an '=' if it takes an argument. for name, flag in fl.items(): longopts.append(name + "=") if len(name) == 1: # one-letter option: allow short flag type also shortopts += name if not flag.boolean: shortopts += ":" longopts.append('undefok=') undefok_flags = [] # In case --undefok is specified, loop to pick up unrecognized # options one by one. unrecognized_opts = [] args = argv[1:] while True: try: if self.__dict__['__use_gnu_getopt']: optlist, unparsed_args = getopt.gnu_getopt(args, shortopts, longopts) else: optlist, unparsed_args = getopt.getopt(args, shortopts, longopts) break except getopt.GetoptError, e: if not e.opt or e.opt in fl: # Not an unrecognized option, reraise the exception as a FlagsError raise FlagsError(e) # Remove offender from args and try again for arg_index in range(len(args)): if ((args[arg_index] == '--' + e.opt) or (args[arg_index] == '-' + e.opt) or (args[arg_index].startswith('--' + e.opt + '='))): unrecognized_opts.append((e.opt, args[arg_index])) args = args[0:arg_index] + args[arg_index+1:] break else: # We should have found the option, so we don't expect to get # here. We could assert, but raising the original exception # might work better. raise FlagsError(e) for name, arg in optlist: if name == '--undefok': flag_names = arg.split(',') undefok_flags.extend(flag_names) # For boolean flags, if --undefok=boolflag is specified, then we should # also accept --noboolflag, in addition to --boolflag. # Since we don't know the type of the undefok'd flag, this will affect # non-boolean flags as well. # NOTE: You shouldn't use --undefok=noboolflag, because then we will # accept --nonoboolflag here. We are choosing not to do the conversion # from noboolflag -> boolflag because of the ambiguity that flag names # can start with 'no'. undefok_flags.extend('no' + name for name in flag_names) continue if name.startswith('--'): # long option name = name[2:] short_option = 0 else: # short option name = name[1:] short_option = 1 if fl.has_key(name): flag = fl[name] if flag.boolean and short_option: arg = 1 flag.Parse(arg) # If there were unrecognized options, raise an exception unless # the options were named via --undefok. for opt, value in unrecognized_opts: if opt not in undefok_flags: raise UnrecognizedFlagError(opt, value) if unparsed_args: if self.__dict__['__use_gnu_getopt']: # if using gnu_getopt just return the program name + remainder of argv. ret_val = argv[:1] + unparsed_args else: # unparsed_args becomes the first non-flag detected by getopt to # the end of argv. Because argv may have been modified above, # return original_argv for this region. ret_val = argv[:1] + original_argv[-len(unparsed_args):] else: ret_val = argv[:1] self._AssertAllValidators() return ret_val def Reset(self): """Resets the values to the point before FLAGS(argv) was called.""" for f in self.FlagDict().values(): f.Unparse() def RegisteredFlags(self): """Returns: a list of the names and short names of all registered flags.""" return self.FlagDict().keys() def FlagValuesDict(self): """Returns: a dictionary that maps flag names to flag values.""" flag_values = {} for flag_name in self.RegisteredFlags(): flag = self.FlagDict()[flag_name] flag_values[flag_name] = flag.value return flag_values def __str__(self): """Generates a help string for all known flags.""" return self.GetHelp() def GetHelp(self, prefix=''): """Generates a help string for all known flags.""" helplist = [] flags_by_module = self.FlagsByModuleDict() if flags_by_module: modules = flags_by_module.keys() modules.sort() # Print the help for the main module first, if possible. main_module = _GetMainModule() if main_module in modules: modules.remove(main_module) modules = [main_module] + modules for module in modules: self.__RenderOurModuleFlags(module, helplist) self.__RenderModuleFlags('gflags', _SPECIAL_FLAGS.FlagDict().values(), helplist) else: # Just print one long list of flags. self.__RenderFlagList( self.FlagDict().values() + _SPECIAL_FLAGS.FlagDict().values(), helplist, prefix) return '\n'.join(helplist) def __RenderModuleFlags(self, module, flags, output_lines, prefix=""): """Generates a help string for a given module.""" if not isinstance(module, str): module = module.__name__ output_lines.append('\n%s%s:' % (prefix, module)) self.__RenderFlagList(flags, output_lines, prefix + " ") def __RenderOurModuleFlags(self, module, output_lines, prefix=""): """Generates a help string for a given module.""" flags = self._GetFlagsDefinedByModule(module) if flags: self.__RenderModuleFlags(module, flags, output_lines, prefix) def __RenderOurModuleKeyFlags(self, module, output_lines, prefix=""): """Generates a help string for the key flags of a given module. Args: module: A module object or a module name (a string). output_lines: A list of strings. The generated help message lines will be appended to this list. prefix: A string that is prepended to each generated help line. """ key_flags = self._GetKeyFlagsForModule(module) if key_flags: self.__RenderModuleFlags(module, key_flags, output_lines, prefix) def ModuleHelp(self, module): """Describe the key flags of a module. Args: module: A module object or a module name (a string). Returns: string describing the key flags of a module. """ helplist = [] self.__RenderOurModuleKeyFlags(module, helplist) return '\n'.join(helplist) def MainModuleHelp(self): """Describe the key flags of the main module. Returns: string describing the key flags of a module. """ return self.ModuleHelp(_GetMainModule()) def __RenderFlagList(self, flaglist, output_lines, prefix=" "): fl = self.FlagDict() special_fl = _SPECIAL_FLAGS.FlagDict() flaglist = [(flag.name, flag) for flag in flaglist] flaglist.sort() flagset = {} for (name, flag) in flaglist: # It's possible this flag got deleted or overridden since being # registered in the per-module flaglist. Check now against the # canonical source of current flag information, the FlagDict. if fl.get(name, None) != flag and special_fl.get(name, None) != flag: # a different flag is using this name now continue # only print help once if flagset.has_key(flag): continue flagset[flag] = 1 flaghelp = "" if flag.short_name: flaghelp += "-%s," % flag.short_name if flag.boolean: flaghelp += "--[no]%s" % flag.name + ":" else: flaghelp += "--%s" % flag.name + ":" flaghelp += " " if flag.help: flaghelp += flag.help flaghelp = TextWrap(flaghelp, indent=prefix+" ", firstline_indent=prefix) if flag.default_as_str: flaghelp += "\n" flaghelp += TextWrap("(default: %s)" % flag.default_as_str, indent=prefix+" ") if flag.parser.syntactic_help: flaghelp += "\n" flaghelp += TextWrap("(%s)" % flag.parser.syntactic_help, indent=prefix+" ") output_lines.append(flaghelp) def get(self, name, default): """Returns the value of a flag (if not None) or a default value. Args: name: A string, the name of a flag. default: Default value to use if the flag value is None. """ value = self.__getattr__(name) if value is not None: # Can't do if not value, b/c value might be '0' or "" return value else: return default def ShortestUniquePrefixes(self, fl): """Returns: dictionary; maps flag names to their shortest unique prefix.""" # Sort the list of flag names sorted_flags = [] for name, flag in fl.items(): sorted_flags.append(name) if flag.boolean: sorted_flags.append('no%s' % name) sorted_flags.sort() # For each name in the sorted list, determine the shortest unique # prefix by comparing itself to the next name and to the previous # name (the latter check uses cached info from the previous loop). shortest_matches = {} prev_idx = 0 for flag_idx in range(len(sorted_flags)): curr = sorted_flags[flag_idx] if flag_idx == (len(sorted_flags) - 1): next = None else: next = sorted_flags[flag_idx+1] next_len = len(next) for curr_idx in range(len(curr)): if (next is None or curr_idx >= next_len or curr[curr_idx] != next[curr_idx]): # curr longer than next or no more chars in common shortest_matches[curr] = curr[:max(prev_idx, curr_idx) + 1] prev_idx = curr_idx break else: # curr shorter than (or equal to) next shortest_matches[curr] = curr prev_idx = curr_idx + 1 # next will need at least one more char return shortest_matches def __IsFlagFileDirective(self, flag_string): """Checks whether flag_string contain a --flagfile=<foo> directive.""" if isinstance(flag_string, type("")): if flag_string.startswith('--flagfile='): return 1 elif flag_string == '--flagfile': return 1 elif flag_string.startswith('-flagfile='): return 1 elif flag_string == '-flagfile': return 1 else: return 0 return 0 def ExtractFilename(self, flagfile_str): """Returns filename from a flagfile_str of form -[-]flagfile=filename. The cases of --flagfile foo and -flagfile foo shouldn't be hitting this function, as they are dealt with in the level above this function. """ if flagfile_str.startswith('--flagfile='): return os.path.expanduser((flagfile_str[(len('--flagfile=')):]).strip()) elif flagfile_str.startswith('-flagfile='): return os.path.expanduser((flagfile_str[(len('-flagfile=')):]).strip()) else: raise FlagsError('Hit illegal --flagfile type: %s' % flagfile_str) def __GetFlagFileLines(self, filename, parsed_file_list): """Returns the useful (!=comments, etc) lines from a file with flags. Args: filename: A string, the name of the flag file. parsed_file_list: A list of the names of the files we have already read. MUTATED BY THIS FUNCTION. Returns: List of strings. See the note below. NOTE(springer): This function checks for a nested --flagfile=<foo> tag and handles the lower file recursively. It returns a list of all the lines that _could_ contain command flags. This is EVERYTHING except whitespace lines and comments (lines starting with '#' or '//'). """ line_list = [] # All line from flagfile. flag_line_list = [] # Subset of lines w/o comments, blanks, flagfile= tags. try: file_obj = open(filename, 'r') except IOError, e_msg: print e_msg print 'ERROR:: Unable to open flagfile: %s' % (filename) return flag_line_list line_list = file_obj.readlines() file_obj.close() parsed_file_list.append(filename) # This is where we check each line in the file we just read. for line in line_list: if line.isspace(): pass # Checks for comment (a line that starts with '#'). elif line.startswith('#') or line.startswith('//'): pass # Checks for a nested "--flagfile=<bar>" flag in the current file. # If we find one, recursively parse down into that file. elif self.__IsFlagFileDirective(line): sub_filename = self.ExtractFilename(line) # We do a little safety check for reparsing a file we've already done. if not sub_filename in parsed_file_list: included_flags = self.__GetFlagFileLines(sub_filename, parsed_file_list) flag_line_list.extend(included_flags) else: # Case of hitting a circularly included file. print >>sys.stderr, ('Warning: Hit circular flagfile dependency: %s' % sub_filename) else: # Any line that's not a comment or a nested flagfile should get # copied into 2nd position. This leaves earlier arguements # further back in the list, thus giving them higher priority. flag_line_list.append(line.strip()) return flag_line_list def ReadFlagsFromFiles(self, argv, force_gnu=True): """Processes command line args, but also allow args to be read from file. Args: argv: A list of strings, usually sys.argv[1:], which may contain one or more flagfile directives of the form --flagfile="./filename". Note that the name of the program (sys.argv[0]) should be omitted. force_gnu: If False, --flagfile parsing obeys normal flag semantics. If True, --flagfile parsing instead follows gnu_getopt semantics. *** WARNING *** force_gnu=False may become the future default! Returns: A new list which has the original list combined with what we read from any flagfile(s). References: Global gflags.FLAG class instance. This function should be called before the normal FLAGS(argv) call. This function scans the input list for a flag that looks like: --flagfile=<somefile>. Then it opens <somefile>, reads all valid key and value pairs and inserts them into the input list between the first item of the list and any subsequent items in the list. Note that your application's flags are still defined the usual way using gflags DEFINE_flag() type functions. Notes (assuming we're getting a commandline of some sort as our input): --> Flags from the command line argv _should_ always take precedence! --> A further "--flagfile=<otherfile.cfg>" CAN be nested in a flagfile. It will be processed after the parent flag file is done. --> For duplicate flags, first one we hit should "win". --> In a flagfile, a line beginning with # or // is a comment. --> Entirely blank lines _should_ be ignored. """ parsed_file_list = [] rest_of_args = argv new_argv = [] while rest_of_args: current_arg = rest_of_args[0] rest_of_args = rest_of_args[1:] if self.__IsFlagFileDirective(current_arg): # This handles the case of -(-)flagfile foo. In this case the # next arg really is part of this one. if current_arg == '--flagfile' or current_arg == '-flagfile': if not rest_of_args: raise IllegalFlagValue('--flagfile with no argument') flag_filename = os.path.expanduser(rest_of_args[0]) rest_of_args = rest_of_args[1:] else: # This handles the case of (-)-flagfile=foo. flag_filename = self.ExtractFilename(current_arg) new_argv[0:0] = self.__GetFlagFileLines(flag_filename, parsed_file_list) else: new_argv.append(current_arg) # Stop parsing after '--', like getopt and gnu_getopt. if current_arg == '--': break # Stop parsing after a non-flag, like getopt. if not current_arg.startswith('-'): if not force_gnu and not self.__dict__['__use_gnu_getopt']: break if rest_of_args: new_argv.extend(rest_of_args) return new_argv def FlagsIntoString(self): """Returns a string with the flags assignments from this FlagValues object. This function ignores flags whose value is None. Each flag assignment is separated by a newline. NOTE: MUST mirror the behavior of the C++ function CommandlineFlagsIntoString from google3/base/commandlineflags.cc. """ s = '' for flag in self.FlagDict().values(): if flag.value is not None: s += flag.Serialize() + '\n' return s def AppendFlagsIntoFile(self, filename): """Appends all flags assignments from this FlagInfo object to a file. Output will be in the format of a flagfile. NOTE: MUST mirror the behavior of the C++ version of AppendFlagsIntoFile from google3/base/commandlineflags.cc. """ out_file = open(filename, 'a') out_file.write(self.FlagsIntoString()) out_file.close() def WriteHelpInXMLFormat(self, outfile=None): """Outputs flag documentation in XML format. NOTE: We use element names that are consistent with those used by the C++ command-line flag library, from google3/base/commandlineflags_reporting.cc. We also use a few new elements (e.g., <key>), but we do not interfere / overlap with existing XML elements used by the C++ library. Please maintain this consistency. Args: outfile: File object we write to. Default None means sys.stdout. """ outfile = outfile or sys.stdout outfile.write('<?xml version=\"1.0\"?>\n') outfile.write('<AllFlags>\n') indent = ' ' _WriteSimpleXMLElement(outfile, 'program', os.path.basename(sys.argv[0]), indent) usage_doc = sys.modules['__main__'].__doc__ if not usage_doc: usage_doc = '\nUSAGE: %s [flags]\n' % sys.argv[0] else: usage_doc = usage_doc.replace('%s', sys.argv[0]) _WriteSimpleXMLElement(outfile, 'usage', usage_doc, indent) # Get list of key flags for the main module. key_flags = self._GetKeyFlagsForModule(_GetMainModule()) # Sort flags by declaring module name and next by flag name. flags_by_module = self.FlagsByModuleDict() all_module_names = list(flags_by_module.keys()) all_module_names.sort() for module_name in all_module_names: flag_list = [(f.name, f) for f in flags_by_module[module_name]] flag_list.sort() for unused_flag_name, flag in flag_list: is_key = flag in key_flags flag.WriteInfoInXMLFormat(outfile, module_name, is_key=is_key, indent=indent) outfile.write('</AllFlags>\n') outfile.flush() def AddValidator(self, validator): """Register new flags validator to be checked. Args: validator: gflags_validators.Validator Raises: AttributeError: if validators work with a non-existing flag. """ for flag_name in validator.GetFlagsNames(): flag = self.FlagDict()[flag_name] flag.validators.append(validator) # end of FlagValues definition # The global FlagValues instance FLAGS = FlagValues() def _MakeXMLSafe(s): """Escapes <, >, and & from s, and removes XML 1.0-illegal chars.""" s = cgi.escape(s) # Escape <, >, and & # Remove characters that cannot appear in an XML 1.0 document # (http://www.w3.org/TR/REC-xml/#charsets). # # NOTE: if there are problems with current solution, one may move to # XML 1.1, which allows such chars, if they're entity-escaped (&#xHH;). s = re.sub(r'[\x00-\x08\x0b\x0c\x0e-\x1f]', '', s) return s def _WriteSimpleXMLElement(outfile, name, value, indent): """Writes a simple XML element. Args: outfile: File object we write the XML element to. name: A string, the name of XML element. value: A Python object, whose string representation will be used as the value of the XML element. indent: A string, prepended to each line of generated output. """ value_str = str(value) if isinstance(value, bool): # Display boolean values as the C++ flag library does: no caps. value_str = value_str.lower() outfile.write('%s<%s>%s</%s>\n' % (indent, name, _MakeXMLSafe(value_str), name)) class Flag: """Information about a command-line flag. 'Flag' objects define the following fields: .name - the name for this flag .default - the default value for this flag .default_as_str - default value as repr'd string, e.g., "'true'" (or None) .value - the most recent parsed value of this flag; set by Parse() .help - a help string or None if no help is available .short_name - the single letter alias for this flag (or None) .boolean - if 'true', this flag does not accept arguments .present - true if this flag was parsed from command line flags. .parser - an ArgumentParser object .serializer - an ArgumentSerializer object .allow_override - the flag may be redefined without raising an error The only public method of a 'Flag' object is Parse(), but it is typically only called by a 'FlagValues' object. The Parse() method is a thin wrapper around the 'ArgumentParser' Parse() method. The parsed value is saved in .value, and the .present attribute is updated. If this flag was already present, a FlagsError is raised. Parse() is also called during __init__ to parse the default value and initialize the .value attribute. This enables other python modules to safely use flags even if the __main__ module neglects to parse the command line arguments. The .present attribute is cleared after __init__ parsing. If the default value is set to None, then the __init__ parsing step is skipped and the .value attribute is initialized to None. Note: The default value is also presented to the user in the help string, so it is important that it be a legal value for this flag. """ def __init__(self, parser, serializer, name, default, help_string, short_name=None, boolean=0, allow_override=0): self.name = name if not help_string: help_string = '(no help available)' self.help = help_string self.short_name = short_name self.boolean = boolean self.present = 0 self.parser = parser self.serializer = serializer self.allow_override = allow_override self.value = None self.validators = [] self.SetDefault(default) def __GetParsedValueAsString(self, value): if value is None: return None if self.serializer: return repr(self.serializer.Serialize(value)) if self.boolean: if value: return repr('true') else: return repr('false') return repr(str(value)) def Parse(self, argument): try: self.value = self.parser.Parse(argument) except ValueError, e: # recast ValueError as IllegalFlagValue raise IllegalFlagValue("flag --%s=%s: %s" % (self.name, argument, e)) self.present += 1 def Unparse(self): if self.default is None: self.value = None else: self.Parse(self.default) self.present = 0 def Serialize(self): if self.value is None: return '' if self.boolean: if self.value: return "--%s" % self.name else: return "--no%s" % self.name else: if not self.serializer: raise FlagsError("Serializer not present for flag %s" % self.name) return "--%s=%s" % (self.name, self.serializer.Serialize(self.value)) def SetDefault(self, value): """Changes the default value (and current value too) for this Flag.""" # We can't allow a None override because it may end up not being # passed to C++ code when we're overriding C++ flags. So we # cowardly bail out until someone fixes the semantics of trying to # pass None to a C++ flag. See swig_flags.Init() for details on # this behavior. # TODO(olexiy): Users can directly call this method, bypassing all flags # validators (we don't have FlagValues here, so we can not check # validators). # The simplest solution I see is to make this method private. # Another approach would be to store reference to the corresponding # FlagValues with each flag, but this seems to be an overkill. if value is None and self.allow_override: raise DuplicateFlagCannotPropagateNoneToSwig(self.name) self.default = value self.Unparse() self.default_as_str = self.__GetParsedValueAsString(self.value) def Type(self): """Returns: a string that describes the type of this Flag.""" # NOTE: we use strings, and not the types.*Type constants because # our flags can have more exotic types, e.g., 'comma separated list # of strings', 'whitespace separated list of strings', etc. return self.parser.Type() def WriteInfoInXMLFormat(self, outfile, module_name, is_key=False, indent=''): """Writes common info about this flag, in XML format. This is information that is relevant to all flags (e.g., name, meaning, etc.). If you defined a flag that has some other pieces of info, then please override _WriteCustomInfoInXMLFormat. Please do NOT override this method. Args: outfile: File object we write to. module_name: A string, the name of the module that defines this flag. is_key: A boolean, True iff this flag is key for main module. indent: A string that is prepended to each generated line. """ outfile.write(indent + '<flag>\n') inner_indent = indent + ' ' if is_key: _WriteSimpleXMLElement(outfile, 'key', 'yes', inner_indent) _WriteSimpleXMLElement(outfile, 'file', module_name, inner_indent) # Print flag features that are relevant for all flags. _WriteSimpleXMLElement(outfile, 'name', self.name, inner_indent) if self.short_name: _WriteSimpleXMLElement(outfile, 'short_name', self.short_name, inner_indent) if self.help: _WriteSimpleXMLElement(outfile, 'meaning', self.help, inner_indent) # The default flag value can either be represented as a string like on the # command line, or as a Python object. We serialize this value in the # latter case in order to remain consistent. if self.serializer and not isinstance(self.default, str): default_serialized = self.serializer.Serialize(self.default) else: default_serialized = self.default _WriteSimpleXMLElement(outfile, 'default', default_serialized, inner_indent) _WriteSimpleXMLElement(outfile, 'current', self.value, inner_indent) _WriteSimpleXMLElement(outfile, 'type', self.Type(), inner_indent) # Print extra flag features this flag may have. self._WriteCustomInfoInXMLFormat(outfile, inner_indent) outfile.write(indent + '</flag>\n') def _WriteCustomInfoInXMLFormat(self, outfile, indent): """Writes extra info about this flag, in XML format. "Extra" means "not already printed by WriteInfoInXMLFormat above." Args: outfile: File object we write to. indent: A string that is prepended to each generated line. """ # Usually, the parser knows the extra details about the flag, so # we just forward the call to it. self.parser.WriteCustomInfoInXMLFormat(outfile, indent) # End of Flag definition class _ArgumentParserCache(type): """Metaclass used to cache and share argument parsers among flags.""" _instances = {} def __call__(mcs, *args, **kwargs): """Returns an instance of the argument parser cls. This method overrides behavior of the __new__ methods in all subclasses of ArgumentParser (inclusive). If an instance for mcs with the same set of arguments exists, this instance is returned, otherwise a new instance is created. If any keyword arguments are defined, or the values in args are not hashable, this method always returns a new instance of cls. Args: args: Positional initializer arguments. kwargs: Initializer keyword arguments. Returns: An instance of cls, shared or new. """ if kwargs: return type.__call__(mcs, *args, **kwargs) else: instances = mcs._instances key = (mcs,) + tuple(args) try: return instances[key] except KeyError: # No cache entry for key exists, create a new one. return instances.setdefault(key, type.__call__(mcs, *args)) except TypeError: # An object in args cannot be hashed, always return # a new instance. return type.__call__(mcs, *args) class ArgumentParser(object): """Base class used to parse and convert arguments. The Parse() method checks to make sure that the string argument is a legal value and convert it to a native type. If the value cannot be converted, it should throw a 'ValueError' exception with a human readable explanation of why the value is illegal. Subclasses should also define a syntactic_help string which may be presented to the user to describe the form of the legal values. Argument parser classes must be stateless, since instances are cached and shared between flags. Initializer arguments are allowed, but all member variables must be derived from initializer arguments only. """ __metaclass__ = _ArgumentParserCache syntactic_help = "" def Parse(self, argument): """Default implementation: always returns its argument unmodified.""" return argument def Type(self): return 'string' def WriteCustomInfoInXMLFormat(self, outfile, indent): pass class ArgumentSerializer: """Base class for generating string representations of a flag value.""" def Serialize(self, value): return str(value) class ListSerializer(ArgumentSerializer): def __init__(self, list_sep): self.list_sep = list_sep def Serialize(self, value): return self.list_sep.join([str(x) for x in value]) # Flags validators def RegisterValidator(flag_name, checker, message='Flag validation failed', flag_values=FLAGS): """Adds a constraint, which will be enforced during program execution. The constraint is validated when flags are initially parsed, and after each change of the corresponding flag's value. Args: flag_name: string, name of the flag to be checked. checker: method to validate the flag. input - value of the corresponding flag (string, boolean, etc. This value will be passed to checker by the library). See file's docstring for examples. output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise gflags_validators.Error(desired_error_message). message: error text to be shown to the user if checker returns False. If checker raises gflags_validators.Error, message from the raised Error will be shown. flag_values: FlagValues Raises: AttributeError: if flag_name is not registered as a valid flag name. """ flag_values.AddValidator(gflags_validators.SimpleValidator(flag_name, checker, message)) def MarkFlagAsRequired(flag_name, flag_values=FLAGS): """Ensure that flag is not None during program execution. Registers a flag validator, which will follow usual validator rules. Args: flag_name: string, name of the flag flag_values: FlagValues Raises: AttributeError: if flag_name is not registered as a valid flag name. """ RegisterValidator(flag_name, lambda value: value is not None, message='Flag --%s must be specified.' % flag_name, flag_values=flag_values) def _RegisterBoundsValidatorIfNeeded(parser, name, flag_values): """Enforce lower and upper bounds for numeric flags. Args: parser: NumericParser (either FloatParser or IntegerParser). Provides lower and upper bounds, and help text to display. name: string, name of the flag flag_values: FlagValues """ if parser.lower_bound is not None or parser.upper_bound is not None: def Checker(value): if value is not None and parser.IsOutsideBounds(value): message = '%s is not %s' % (value, parser.syntactic_help) raise gflags_validators.Error(message) return True RegisterValidator(name, Checker, flag_values=flag_values) # The DEFINE functions are explained in mode details in the module doc string. def DEFINE(parser, name, default, help, flag_values=FLAGS, serializer=None, **args): """Registers a generic Flag object. NOTE: in the docstrings of all DEFINE* functions, "registers" is short for "creates a new flag and registers it". Auxiliary function: clients should use the specialized DEFINE_<type> function instead. Args: parser: ArgumentParser that is used to parse the flag arguments. name: A string, the flag name. default: The default value of the flag. help: A help string. flag_values: FlagValues object the flag will be registered with. serializer: ArgumentSerializer that serializes the flag value. args: Dictionary with extra keyword args that are passes to the Flag __init__. """ DEFINE_flag(Flag(parser, serializer, name, default, help, **args), flag_values) def DEFINE_flag(flag, flag_values=FLAGS): """Registers a 'Flag' object with a 'FlagValues' object. By default, the global FLAGS 'FlagValue' object is used. Typical users will use one of the more specialized DEFINE_xxx functions, such as DEFINE_string or DEFINE_integer. But developers who need to create Flag objects themselves should use this function to register their flags. """ # copying the reference to flag_values prevents pychecker warnings fv = flag_values fv[flag.name] = flag # Tell flag_values who's defining the flag. if isinstance(flag_values, FlagValues): # Regarding the above isinstance test: some users pass funny # values of flag_values (e.g., {}) in order to avoid the flag # registration (in the past, there used to be a flag_values == # FLAGS test here) and redefine flags with the same name (e.g., # debug). To avoid breaking their code, we perform the # registration only if flag_values is a real FlagValues object. flag_values._RegisterFlagByModule(_GetCallingModule(), flag) def _InternalDeclareKeyFlags(flag_names, flag_values=FLAGS, key_flag_values=None): """Declares a flag as key for the calling module. Internal function. User code should call DECLARE_key_flag or ADOPT_module_key_flags instead. Args: flag_names: A list of strings that are names of already-registered Flag objects. flag_values: A FlagValues object that the flags listed in flag_names have registered with (the value of the flag_values argument from the DEFINE_* calls that defined those flags). This should almost never need to be overridden. key_flag_values: A FlagValues object that (among possibly many other things) keeps track of the key flags for each module. Default None means "same as flag_values". This should almost never need to be overridden. Raises: UnrecognizedFlagError: when we refer to a flag that was not defined yet. """ key_flag_values = key_flag_values or flag_values module = _GetCallingModule() for flag_name in flag_names: if flag_name not in flag_values: raise UnrecognizedFlagError(flag_name) flag = flag_values.FlagDict()[flag_name] key_flag_values._RegisterKeyFlagForModule(module, flag) def DECLARE_key_flag(flag_name, flag_values=FLAGS): """Declares one flag as key to the current module. Key flags are flags that are deemed really important for a module. They are important when listing help messages; e.g., if the --helpshort command-line flag is used, then only the key flags of the main module are listed (instead of all flags, as in the case of --help). Sample usage: flags.DECLARED_key_flag('flag_1') Args: flag_name: A string, the name of an already declared flag. (Redeclaring flags as key, including flags implicitly key because they were declared in this module, is a no-op.) flag_values: A FlagValues object. This should almost never need to be overridden. """ if flag_name in _SPECIAL_FLAGS: # Take care of the special flags, e.g., --flagfile, --undefok. # These flags are defined in _SPECIAL_FLAGS, and are treated # specially during flag parsing, taking precedence over the # user-defined flags. _InternalDeclareKeyFlags([flag_name], flag_values=_SPECIAL_FLAGS, key_flag_values=flag_values) return _InternalDeclareKeyFlags([flag_name], flag_values=flag_values) def ADOPT_module_key_flags(module, flag_values=FLAGS): """Declares that all flags key to a module are key to the current module. Args: module: A module object. flag_values: A FlagValues object. This should almost never need to be overridden. Raises: FlagsError: When given an argument that is a module name (a string), instead of a module object. """ # NOTE(salcianu): an even better test would be if not # isinstance(module, types.ModuleType) but I didn't want to import # types for such a tiny use. if isinstance(module, str): raise FlagsError('Received module name %s; expected a module object.' % module) _InternalDeclareKeyFlags( [f.name for f in flag_values._GetKeyFlagsForModule(module.__name__)], flag_values=flag_values) # If module is this flag module, take _SPECIAL_FLAGS into account. if module == _GetThisModuleObjectAndName()[0]: _InternalDeclareKeyFlags( # As we associate flags with _GetCallingModule(), the special # flags defined in this module are incorrectly registered with # a different module. So, we can't use _GetKeyFlagsForModule. # Instead, we take all flags from _SPECIAL_FLAGS (a private # FlagValues, where no other module should register flags). [f.name for f in _SPECIAL_FLAGS.FlagDict().values()], flag_values=_SPECIAL_FLAGS, key_flag_values=flag_values) # # STRING FLAGS # def DEFINE_string(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value can be any string.""" parser = ArgumentParser() serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) # # BOOLEAN FLAGS # # and the special HELP flags. class BooleanParser(ArgumentParser): """Parser of boolean values.""" def Convert(self, argument): """Converts the argument to a boolean; raise ValueError on errors.""" if type(argument) == str: if argument.lower() in ['true', 't', '1']: return True elif argument.lower() in ['false', 'f', '0']: return False bool_argument = bool(argument) if argument == bool_argument: # The argument is a valid boolean (True, False, 0, or 1), and not just # something that always converts to bool (list, string, int, etc.). return bool_argument raise ValueError('Non-boolean argument to boolean flag', argument) def Parse(self, argument): val = self.Convert(argument) return val def Type(self): return 'bool' class BooleanFlag(Flag): """Basic boolean flag. Boolean flags do not take any arguments, and their value is either True (1) or False (0). The false value is specified on the command line by prepending the word 'no' to either the long or the short flag name. For example, if a Boolean flag was created whose long name was 'update' and whose short name was 'x', then this flag could be explicitly unset through either --noupdate or --nox. """ def __init__(self, name, default, help, short_name=None, **args): p = BooleanParser() Flag.__init__(self, p, None, name, default, help, short_name, 1, **args) if not self.help: self.help = "a boolean value" def DEFINE_boolean(name, default, help, flag_values=FLAGS, **args): """Registers a boolean flag. Such a boolean flag does not take an argument. If a user wants to specify a false value explicitly, the long option beginning with 'no' must be used: i.e. --noflag This flag will have a value of None, True or False. None is possible if default=None and the user does not specify the flag on the command line. """ DEFINE_flag(BooleanFlag(name, default, help, **args), flag_values) # Match C++ API to unconfuse C++ people. DEFINE_bool = DEFINE_boolean class HelpFlag(BooleanFlag): """ HelpFlag is a special boolean flag that prints usage information and raises a SystemExit exception if it is ever found in the command line arguments. Note this is called with allow_override=1, so other apps can define their own --help flag, replacing this one, if they want. """ def __init__(self): BooleanFlag.__init__(self, "help", 0, "show this help", short_name="?", allow_override=1) def Parse(self, arg): if arg: doc = sys.modules["__main__"].__doc__ flags = str(FLAGS) print doc or ("\nUSAGE: %s [flags]\n" % sys.argv[0]) if flags: print "flags:" print flags sys.exit(1) class HelpXMLFlag(BooleanFlag): """Similar to HelpFlag, but generates output in XML format.""" def __init__(self): BooleanFlag.__init__(self, 'helpxml', False, 'like --help, but generates XML output', allow_override=1) def Parse(self, arg): if arg: FLAGS.WriteHelpInXMLFormat(sys.stdout) sys.exit(1) class HelpshortFlag(BooleanFlag): """ HelpshortFlag is a special boolean flag that prints usage information for the "main" module, and rasies a SystemExit exception if it is ever found in the command line arguments. Note this is called with allow_override=1, so other apps can define their own --helpshort flag, replacing this one, if they want. """ def __init__(self): BooleanFlag.__init__(self, "helpshort", 0, "show usage only for this module", allow_override=1) def Parse(self, arg): if arg: doc = sys.modules["__main__"].__doc__ flags = FLAGS.MainModuleHelp() print doc or ("\nUSAGE: %s [flags]\n" % sys.argv[0]) if flags: print "flags:" print flags sys.exit(1) # # Numeric parser - base class for Integer and Float parsers # class NumericParser(ArgumentParser): """Parser of numeric values. Parsed value may be bounded to a given upper and lower bound. """ def IsOutsideBounds(self, val): return ((self.lower_bound is not None and val < self.lower_bound) or (self.upper_bound is not None and val > self.upper_bound)) def Parse(self, argument): val = self.Convert(argument) if self.IsOutsideBounds(val): raise ValueError("%s is not %s" % (val, self.syntactic_help)) return val def WriteCustomInfoInXMLFormat(self, outfile, indent): if self.lower_bound is not None: _WriteSimpleXMLElement(outfile, 'lower_bound', self.lower_bound, indent) if self.upper_bound is not None: _WriteSimpleXMLElement(outfile, 'upper_bound', self.upper_bound, indent) def Convert(self, argument): """Default implementation: always returns its argument unmodified.""" return argument # End of Numeric Parser # # FLOAT FLAGS # class FloatParser(NumericParser): """Parser of floating point values. Parsed value may be bounded to a given upper and lower bound. """ number_article = "a" number_name = "number" syntactic_help = " ".join((number_article, number_name)) def __init__(self, lower_bound=None, upper_bound=None): super(FloatParser, self).__init__() self.lower_bound = lower_bound self.upper_bound = upper_bound sh = self.syntactic_help if lower_bound is not None and upper_bound is not None: sh = ("%s in the range [%s, %s]" % (sh, lower_bound, upper_bound)) elif lower_bound == 0: sh = "a non-negative %s" % self.number_name elif upper_bound == 0: sh = "a non-positive %s" % self.number_name elif upper_bound is not None: sh = "%s <= %s" % (self.number_name, upper_bound) elif lower_bound is not None: sh = "%s >= %s" % (self.number_name, lower_bound) self.syntactic_help = sh def Convert(self, argument): """Converts argument to a float; raises ValueError on errors.""" return float(argument) def Type(self): return 'float' # End of FloatParser def DEFINE_float(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value must be a float. If lower_bound or upper_bound are set, then this flag must be within the given range. """ parser = FloatParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) _RegisterBoundsValidatorIfNeeded(parser, name, flag_values=flag_values) # # INTEGER FLAGS # class IntegerParser(NumericParser): """Parser of an integer value. Parsed value may be bounded to a given upper and lower bound. """ number_article = "an" number_name = "integer" syntactic_help = " ".join((number_article, number_name)) def __init__(self, lower_bound=None, upper_bound=None): super(IntegerParser, self).__init__() self.lower_bound = lower_bound self.upper_bound = upper_bound sh = self.syntactic_help if lower_bound is not None and upper_bound is not None: sh = ("%s in the range [%s, %s]" % (sh, lower_bound, upper_bound)) elif lower_bound == 1: sh = "a positive %s" % self.number_name elif upper_bound == -1: sh = "a negative %s" % self.number_name elif lower_bound == 0: sh = "a non-negative %s" % self.number_name elif upper_bound == 0: sh = "a non-positive %s" % self.number_name elif upper_bound is not None: sh = "%s <= %s" % (self.number_name, upper_bound) elif lower_bound is not None: sh = "%s >= %s" % (self.number_name, lower_bound) self.syntactic_help = sh def Convert(self, argument): __pychecker__ = 'no-returnvalues' if type(argument) == str: base = 10 if len(argument) > 2 and argument[0] == "0" and argument[1] == "x": base = 16 try: return int(argument, base) # ValueError is thrown when argument is a string, and overflows an int. except ValueError: return long(argument, base) else: try: return int(argument) # OverflowError is thrown when argument is numeric, and overflows an int. except OverflowError: return long(argument) def Type(self): return 'int' def DEFINE_integer(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value must be an integer. If lower_bound, or upper_bound are set, then this flag must be within the given range. """ parser = IntegerParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) _RegisterBoundsValidatorIfNeeded(parser, name, flag_values=flag_values) # # ENUM FLAGS # class EnumParser(ArgumentParser): """Parser of a string enum value (a string value from a given set). If enum_values (see below) is not specified, any string is allowed. """ def __init__(self, enum_values=None): super(EnumParser, self).__init__() self.enum_values = enum_values def Parse(self, argument): if self.enum_values and argument not in self.enum_values: raise ValueError("value should be one of <%s>" % "|".join(self.enum_values)) return argument def Type(self): return 'string enum' class EnumFlag(Flag): """Basic enum flag; its value can be any string from list of enum_values.""" def __init__(self, name, default, help, enum_values=None, short_name=None, **args): enum_values = enum_values or [] p = EnumParser(enum_values) g = ArgumentSerializer() Flag.__init__(self, p, g, name, default, help, short_name, **args) if not self.help: self.help = "an enum string" self.help = "<%s>: %s" % ("|".join(enum_values), self.help) def _WriteCustomInfoInXMLFormat(self, outfile, indent): for enum_value in self.parser.enum_values: _WriteSimpleXMLElement(outfile, 'enum_value', enum_value, indent) def DEFINE_enum(name, default, enum_values, help, flag_values=FLAGS, **args): """Registers a flag whose value can be any string from enum_values.""" DEFINE_flag(EnumFlag(name, default, help, enum_values, ** args), flag_values) # # LIST FLAGS # class BaseListParser(ArgumentParser): """Base class for a parser of lists of strings. To extend, inherit from this class; from the subclass __init__, call BaseListParser.__init__(self, token, name) where token is a character used to tokenize, and name is a description of the separator. """ def __init__(self, token=None, name=None): assert name super(BaseListParser, self).__init__() self._token = token self._name = name self.syntactic_help = "a %s separated list" % self._name def Parse(self, argument): if isinstance(argument, list): return argument elif argument == '': return [] else: return [s.strip() for s in argument.split(self._token)] def Type(self): return '%s separated list of strings' % self._name class ListParser(BaseListParser): """Parser for a comma-separated list of strings.""" def __init__(self): BaseListParser.__init__(self, ',', 'comma') def WriteCustomInfoInXMLFormat(self, outfile, indent): BaseListParser.WriteCustomInfoInXMLFormat(self, outfile, indent) _WriteSimpleXMLElement(outfile, 'list_separator', repr(','), indent) class WhitespaceSeparatedListParser(BaseListParser): """Parser for a whitespace-separated list of strings.""" def __init__(self): BaseListParser.__init__(self, None, 'whitespace') def WriteCustomInfoInXMLFormat(self, outfile, indent): BaseListParser.WriteCustomInfoInXMLFormat(self, outfile, indent) separators = list(string.whitespace) separators.sort() for ws_char in string.whitespace: _WriteSimpleXMLElement(outfile, 'list_separator', repr(ws_char), indent) def DEFINE_list(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value is a comma-separated list of strings.""" parser = ListParser() serializer = ListSerializer(',') DEFINE(parser, name, default, help, flag_values, serializer, **args) def DEFINE_spaceseplist(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value is a whitespace-separated list of strings. Any whitespace can be used as a separator. """ parser = WhitespaceSeparatedListParser() serializer = ListSerializer(' ') DEFINE(parser, name, default, help, flag_values, serializer, **args) # # MULTI FLAGS # class MultiFlag(Flag): """A flag that can appear multiple time on the command-line. The value of such a flag is a list that contains the individual values from all the appearances of that flag on the command-line. See the __doc__ for Flag for most behavior of this class. Only differences in behavior are described here: * The default value may be either a single value or a list of values. A single value is interpreted as the [value] singleton list. * The value of the flag is always a list, even if the option was only supplied once, and even if the default value is a single value """ def __init__(self, *args, **kwargs): Flag.__init__(self, *args, **kwargs) self.help += ';\n repeat this option to specify a list of values' def Parse(self, arguments): """Parses one or more arguments with the installed parser. Args: arguments: a single argument or a list of arguments (typically a list of default values); a single argument is converted internally into a list containing one item. """ if not isinstance(arguments, list): # Default value may be a list of values. Most other arguments # will not be, so convert them into a single-item list to make # processing simpler below. arguments = [arguments] if self.present: # keep a backup reference to list of previously supplied option values values = self.value else: # "erase" the defaults with an empty list values = [] for item in arguments: # have Flag superclass parse argument, overwriting self.value reference Flag.Parse(self, item) # also increments self.present values.append(self.value) # put list of option values back in the 'value' attribute self.value = values def Serialize(self): if not self.serializer: raise FlagsError("Serializer not present for flag %s" % self.name) if self.value is None: return '' s = '' multi_value = self.value for self.value in multi_value: if s: s += ' ' s += Flag.Serialize(self) self.value = multi_value return s def Type(self): return 'multi ' + self.parser.Type() def DEFINE_multi(parser, serializer, name, default, help, flag_values=FLAGS, **args): """Registers a generic MultiFlag that parses its args with a given parser. Auxiliary function. Normal users should NOT use it directly. Developers who need to create their own 'Parser' classes for options which can appear multiple times can call this module function to register their flags. """ DEFINE_flag(MultiFlag(parser, serializer, name, default, help, **args), flag_values) def DEFINE_multistring(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value can be a list of any strings. Use the flag on the command line multiple times to place multiple string values into the list. The 'default' may be a single string (which will be converted into a single-element list) or a list of strings. """ parser = ArgumentParser() serializer = ArgumentSerializer() DEFINE_multi(parser, serializer, name, default, help, flag_values, **args) def DEFINE_multi_int(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value can be a list of arbitrary integers. Use the flag on the command line multiple times to place multiple integer values into the list. The 'default' may be a single integer (which will be converted into a single-element list) or a list of integers. """ parser = IntegerParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE_multi(parser, serializer, name, default, help, flag_values, **args) # Now register the flags that we want to exist in all applications. # These are all defined with allow_override=1, so user-apps can use # these flagnames for their own purposes, if they want. DEFINE_flag(HelpFlag()) DEFINE_flag(HelpshortFlag()) DEFINE_flag(HelpXMLFlag()) # Define special flags here so that help may be generated for them. # NOTE: Please do NOT use _SPECIAL_FLAGS from outside this module. _SPECIAL_FLAGS = FlagValues() DEFINE_string( 'flagfile', "", "Insert flag definitions from the given file into the command line.", _SPECIAL_FLAGS) DEFINE_string( 'undefok', "", "comma-separated list of flag names that it is okay to specify " "on the command line even if the program does not define a flag " "with that name. IMPORTANT: flags in this list that have " "arguments MUST use the --flag=value format.", _SPECIAL_FLAGS)
Python
#!/usr/bin/env python # Copyright (c) 2010, Google Inc. # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. """Module to enforce different constraints on flags. A validator represents an invariant, enforced over a one or more flags. See 'FLAGS VALIDATORS' in flags.py's docstring for a usage manual. """ __author__ = 'olexiy@google.com (Olexiy Oryeshko)' class Error(Exception): """Thrown If validator constraint is not satisfied.""" class Validator(object): """Base class for flags validators. Users should NOT overload these classes, and use flags.Register... methods instead. """ # Used to assign each validator an unique insertion_index validators_count = 0 def __init__(self, checker, message): """Constructor to create all validators. Args: checker: function to verify the constraint. Input of this method varies, see SimpleValidator and DictionaryValidator for a detailed description. message: string, error message to be shown to the user """ self.checker = checker self.message = message Validator.validators_count += 1 # Used to assert validators in the order they were registered (CL/18694236) self.insertion_index = Validator.validators_count def Verify(self, flag_values): """Verify that constraint is satisfied. flags library calls this method to verify Validator's constraint. Args: flag_values: flags.FlagValues, containing all flags Raises: Error: if constraint is not satisfied. """ param = self._GetInputToCheckerFunction(flag_values) if not self.checker(param): raise Error(self.message) def GetFlagsNames(self): """Return the names of the flags checked by this validator. Returns: [string], names of the flags """ raise NotImplementedError('This method should be overloaded') def PrintFlagsWithValues(self, flag_values): raise NotImplementedError('This method should be overloaded') def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues, containing all flags. Returns: Return type depends on the specific validator. """ raise NotImplementedError('This method should be overloaded') class SimpleValidator(Validator): """Validator behind RegisterValidator() method. Validates that a single flag passes its checker function. The checker function takes the flag value and returns True (if value looks fine) or, if flag value is not valid, either returns False or raises an Exception.""" def __init__(self, flag_name, checker, message): """Constructor. Args: flag_name: string, name of the flag. checker: function to verify the validator. input - value of the corresponding flag (string, boolean, etc). output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise Error. message: string, error message to be shown to the user if validator's condition is not satisfied """ super(SimpleValidator, self).__init__(checker, message) self.flag_name = flag_name def GetFlagsNames(self): return [self.flag_name] def PrintFlagsWithValues(self, flag_values): return 'flag --%s=%s' % (self.flag_name, flag_values[self.flag_name].value) def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues Returns: value of the corresponding flag. """ return flag_values[self.flag_name].value class DictionaryValidator(Validator): """Validator behind RegisterDictionaryValidator method. Validates that flag values pass their common checker function. The checker function takes flag values and returns True (if values look fine) or, if values are not valid, either returns False or raises an Exception. """ def __init__(self, flag_names, checker, message): """Constructor. Args: flag_names: [string], containing names of the flags used by checker. checker: function to verify the validator. input - dictionary, with keys() being flag_names, and value for each key being the value of the corresponding flag (string, boolean, etc). output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise Error. message: string, error message to be shown to the user if validator's condition is not satisfied """ super(DictionaryValidator, self).__init__(checker, message) self.flag_names = flag_names def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues Returns: dictionary, with keys() being self.lag_names, and value for each key being the value of the corresponding flag (string, boolean, etc). """ return dict([key, flag_values[key].value] for key in self.flag_names) def PrintFlagsWithValues(self, flag_values): prefix = 'flags ' flags_with_values = [] for key in self.flag_names: flags_with_values.append('%s=%s' % (key, flag_values[key].value)) return prefix + ', '.join(flags_with_values) def GetFlagsNames(self): return self.flag_names
Python
#!/usr/bin/env python # Copyright (c) 2007, Google Inc. # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. # # --- # Author: Chad Lester # Design and style contributions by: # Amit Patel, Bogdan Cocosel, Daniel Dulitz, Eric Tiedemann, # Eric Veach, Laurence Gonsalves, Matthew Springer # Code reorganized a bit by Craig Silverstein """This module is used to define and parse command line flags. This module defines a *distributed* flag-definition policy: rather than an application having to define all flags in or near main(), each python module defines flags that are useful to it. When one python module imports another, it gains access to the other's flags. (This is implemented by having all modules share a common, global registry object containing all the flag information.) Flags are defined through the use of one of the DEFINE_xxx functions. The specific function used determines how the flag is parsed, checked, and optionally type-converted, when it's seen on the command line. IMPLEMENTATION: DEFINE_* creates a 'Flag' object and registers it with a 'FlagValues' object (typically the global FlagValues FLAGS, defined here). The 'FlagValues' object can scan the command line arguments and pass flag arguments to the corresponding 'Flag' objects for value-checking and type conversion. The converted flag values are available as attributes of the 'FlagValues' object. Code can access the flag through a FlagValues object, for instance gflags.FLAGS.myflag. Typically, the __main__ module passes the command line arguments to gflags.FLAGS for parsing. At bottom, this module calls getopt(), so getopt functionality is supported, including short- and long-style flags, and the use of -- to terminate flags. Methods defined by the flag module will throw 'FlagsError' exceptions. The exception argument will be a human-readable string. FLAG TYPES: This is a list of the DEFINE_*'s that you can do. All flags take a name, default value, help-string, and optional 'short' name (one-letter name). Some flags have other arguments, which are described with the flag. DEFINE_string: takes any input, and interprets it as a string. DEFINE_bool or DEFINE_boolean: typically does not take an argument: say --myflag to set FLAGS.myflag to true, or --nomyflag to set FLAGS.myflag to false. Alternately, you can say --myflag=true or --myflag=t or --myflag=1 or --myflag=false or --myflag=f or --myflag=0 DEFINE_float: takes an input and interprets it as a floating point number. Takes optional args lower_bound and upper_bound; if the number specified on the command line is out of range, it will raise a FlagError. DEFINE_integer: takes an input and interprets it as an integer. Takes optional args lower_bound and upper_bound as for floats. DEFINE_enum: takes a list of strings which represents legal values. If the command-line value is not in this list, raise a flag error. Otherwise, assign to FLAGS.flag as a string. DEFINE_list: Takes a comma-separated list of strings on the commandline. Stores them in a python list object. DEFINE_spaceseplist: Takes a space-separated list of strings on the commandline. Stores them in a python list object. Example: --myspacesepflag "foo bar baz" DEFINE_multistring: The same as DEFINE_string, except the flag can be specified more than once on the commandline. The result is a python list object (list of strings), even if the flag is only on the command line once. DEFINE_multi_int: The same as DEFINE_integer, except the flag can be specified more than once on the commandline. The result is a python list object (list of ints), even if the flag is only on the command line once. SPECIAL FLAGS: There are a few flags that have special meaning: --help prints a list of all the flags in a human-readable fashion --helpshort prints a list of all key flags (see below). --helpxml prints a list of all flags, in XML format. DO NOT parse the output of --help and --helpshort. Instead, parse the output of --helpxml. For more info, see "OUTPUT FOR --helpxml" below. --flagfile=foo read flags from file foo. --undefok=f1,f2 ignore unrecognized option errors for f1,f2. For boolean flags, you should use --undefok=boolflag, and --boolflag and --noboolflag will be accepted. Do not use --undefok=noboolflag. -- as in getopt(), terminates flag-processing FLAGS VALIDATORS: If your program: - requires flag X to be specified - needs flag Y to match a regular expression - or requires any more general constraint to be satisfied then validators are for you! Each validator represents a constraint over one flag, which is enforced starting from the initial parsing of the flags and until the program terminates. Also, lower_bound and upper_bound for numerical flags are enforced using flag validators. Howto: If you want to enforce a constraint over one flag, use flags.RegisterValidator(flag_name, checker, message='Flag validation failed', flag_values=FLAGS) After flag values are initially parsed, and after any change to the specified flag, method checker(flag_value) will be executed. If constraint is not satisfied, an IllegalFlagValue exception will be raised. See RegisterValidator's docstring for a detailed explanation on how to construct your own checker. EXAMPLE USAGE: FLAGS = flags.FLAGS flags.DEFINE_integer('my_version', 0, 'Version number.') flags.DEFINE_string('filename', None, 'Input file name', short_name='f') flags.RegisterValidator('my_version', lambda value: value % 2 == 0, message='--my_version must be divisible by 2') flags.MarkFlagAsRequired('filename') NOTE ON --flagfile: Flags may be loaded from text files in addition to being specified on the commandline. Any flags you don't feel like typing, throw them in a file, one flag per line, for instance: --myflag=myvalue --nomyboolean_flag You then specify your file with the special flag '--flagfile=somefile'. You CAN recursively nest flagfile= tokens OR use multiple files on the command line. Lines beginning with a single hash '#' or a double slash '//' are comments in your flagfile. Any flagfile=<file> will be interpreted as having a relative path from the current working directory rather than from the place the file was included from: myPythonScript.py --flagfile=config/somefile.cfg If somefile.cfg includes further --flagfile= directives, these will be referenced relative to the original CWD, not from the directory the including flagfile was found in! The caveat applies to people who are including a series of nested files in a different dir than they are executing out of. Relative path names are always from CWD, not from the directory of the parent include flagfile. We do now support '~' expanded directory names. Absolute path names ALWAYS work! EXAMPLE USAGE: import gflags FLAGS = gflags.FLAGS # Flag names are globally defined! So in general, we need to be # careful to pick names that are unlikely to be used by other libraries. # If there is a conflict, we'll get an error at import time. gflags.DEFINE_string('name', 'Mr. President', 'your name') gflags.DEFINE_integer('age', None, 'your age in years', lower_bound=0) gflags.DEFINE_boolean('debug', False, 'produces debugging output') gflags.DEFINE_enum('gender', 'male', ['male', 'female'], 'your gender') def main(argv): try: argv = FLAGS(argv) # parse flags except gflags.FlagsError, e: print '%s\\nUsage: %s ARGS\\n%s' % (e, sys.argv[0], FLAGS) sys.exit(1) if FLAGS.debug: print 'non-flag arguments:', argv print 'Happy Birthday', FLAGS.name if FLAGS.age is not None: print 'You are a %s, who is %d years old' % (FLAGS.gender, FLAGS.age) if __name__ == '__main__': main(sys.argv) KEY FLAGS: As we already explained, each module gains access to all flags defined by all the other modules it transitively imports. In the case of non-trivial scripts, this means a lot of flags ... For documentation purposes, it is good to identify the flags that are key (i.e., really important) to a module. Clearly, the concept of "key flag" is a subjective one. When trying to determine whether a flag is key to a module or not, assume that you are trying to explain your module to a potential user: which flags would you really like to mention first? We'll describe shortly how to declare which flags are key to a module. For the moment, assume we know the set of key flags for each module. Then, if you use the app.py module, you can use the --helpshort flag to print only the help for the flags that are key to the main module, in a human-readable format. NOTE: If you need to parse the flag help, do NOT use the output of --help / --helpshort. That output is meant for human consumption, and may be changed in the future. Instead, use --helpxml; flags that are key for the main module are marked there with a <key>yes</key> element. The set of key flags for a module M is composed of: 1. Flags defined by module M by calling a DEFINE_* function. 2. Flags that module M explictly declares as key by using the function DECLARE_key_flag(<flag_name>) 3. Key flags of other modules that M specifies by using the function ADOPT_module_key_flags(<other_module>) This is a "bulk" declaration of key flags: each flag that is key for <other_module> becomes key for the current module too. Notice that if you do not use the functions described at points 2 and 3 above, then --helpshort prints information only about the flags defined by the main module of our script. In many cases, this behavior is good enough. But if you move part of the main module code (together with the related flags) into a different module, then it is nice to use DECLARE_key_flag / ADOPT_module_key_flags and make sure --helpshort lists all relevant flags (otherwise, your code refactoring may confuse your users). Note: each of DECLARE_key_flag / ADOPT_module_key_flags has its own pluses and minuses: DECLARE_key_flag is more targeted and may lead a more focused --helpshort documentation. ADOPT_module_key_flags is good for cases when an entire module is considered key to the current script. Also, it does not require updates to client scripts when a new flag is added to the module. EXAMPLE USAGE 2 (WITH KEY FLAGS): Consider an application that contains the following three files (two auxiliary modules and a main module): File libfoo.py: import gflags gflags.DEFINE_integer('num_replicas', 3, 'Number of replicas to start') gflags.DEFINE_boolean('rpc2', True, 'Turn on the usage of RPC2.') ... some code ... File libbar.py: import gflags gflags.DEFINE_string('bar_gfs_path', '/gfs/path', 'Path to the GFS files for libbar.') gflags.DEFINE_string('email_for_bar_errors', 'bar-team@google.com', 'Email address for bug reports about module libbar.') gflags.DEFINE_boolean('bar_risky_hack', False, 'Turn on an experimental and buggy optimization.') ... some code ... File myscript.py: import gflags import libfoo import libbar gflags.DEFINE_integer('num_iterations', 0, 'Number of iterations.') # Declare that all flags that are key for libfoo are # key for this module too. gflags.ADOPT_module_key_flags(libfoo) # Declare that the flag --bar_gfs_path (defined in libbar) is key # for this module. gflags.DECLARE_key_flag('bar_gfs_path') ... some code ... When myscript is invoked with the flag --helpshort, the resulted help message lists information about all the key flags for myscript: --num_iterations, --num_replicas, --rpc2, and --bar_gfs_path (in addition to the special flags --help and --helpshort). Of course, myscript uses all the flags declared by it (in this case, just --num_replicas) or by any of the modules it transitively imports (e.g., the modules libfoo, libbar). E.g., it can access the value of FLAGS.bar_risky_hack, even if --bar_risky_hack is not declared as a key flag for myscript. OUTPUT FOR --helpxml: The --helpxml flag generates output with the following structure: <?xml version="1.0"?> <AllFlags> <program>PROGRAM_BASENAME</program> <usage>MAIN_MODULE_DOCSTRING</usage> (<flag> [<key>yes</key>] <file>DECLARING_MODULE</file> <name>FLAG_NAME</name> <meaning>FLAG_HELP_MESSAGE</meaning> <default>DEFAULT_FLAG_VALUE</default> <current>CURRENT_FLAG_VALUE</current> <type>FLAG_TYPE</type> [OPTIONAL_ELEMENTS] </flag>)* </AllFlags> Notes: 1. The output is intentionally similar to the output generated by the C++ command-line flag library. The few differences are due to the Python flags that do not have a C++ equivalent (at least not yet), e.g., DEFINE_list. 2. New XML elements may be added in the future. 3. DEFAULT_FLAG_VALUE is in serialized form, i.e., the string you can pass for this flag on the command-line. E.g., for a flag defined using DEFINE_list, this field may be foo,bar, not ['foo', 'bar']. 4. CURRENT_FLAG_VALUE is produced using str(). This means that the string 'false' will be represented in the same way as the boolean False. Using repr() would have removed this ambiguity and simplified parsing, but would have broken the compatibility with the C++ command-line flags. 5. OPTIONAL_ELEMENTS describe elements relevant for certain kinds of flags: lower_bound, upper_bound (for flags that specify bounds), enum_value (for enum flags), list_separator (for flags that consist of a list of values, separated by a special token). 6. We do not provide any example here: please use --helpxml instead. """ import cgi import getopt import os import re import string import sys import gflags_validators # Are we running at least python 2.2? try: if tuple(sys.version_info[:3]) < (2,2,0): raise NotImplementedError("requires python 2.2.0 or later") except AttributeError: # a very old python, that lacks sys.version_info raise NotImplementedError("requires python 2.2.0 or later") # If we're not running at least python 2.2.1, define True, False, and bool. # Thanks, Guido, for the code. try: True, False, bool except NameError: False = 0 True = 1 def bool(x): if x: return True else: return False # Are we running under pychecker? _RUNNING_PYCHECKER = 'pychecker.python' in sys.modules def _GetCallingModule(): """Returns the name of the module that's calling into this module. We generally use this function to get the name of the module calling a DEFINE_foo... function. """ # Walk down the stack to find the first globals dict that's not ours. for depth in range(1, sys.getrecursionlimit()): if not sys._getframe(depth).f_globals is globals(): globals_for_frame = sys._getframe(depth).f_globals module_name = _GetModuleObjectAndName(globals_for_frame)[1] if module_name is not None: return module_name raise AssertionError("No module was found") def _GetThisModuleObjectAndName(): """Returns: (module object, module name) for this module.""" return _GetModuleObjectAndName(globals()) # module exceptions: class FlagsError(Exception): """The base class for all flags errors.""" pass class DuplicateFlag(FlagsError): """Raised if there is a flag naming conflict.""" pass class DuplicateFlagCannotPropagateNoneToSwig(DuplicateFlag): """Special case of DuplicateFlag -- SWIG flag value can't be set to None. This can be raised when a duplicate flag is created. Even if allow_override is True, we still abort if the new value is None, because it's currently impossible to pass None default value back to SWIG. See FlagValues.SetDefault for details. """ pass # A DuplicateFlagError conveys more information than a # DuplicateFlag. Since there are external modules that create # DuplicateFlags, the interface to DuplicateFlag shouldn't change. class DuplicateFlagError(DuplicateFlag): def __init__(self, flagname, flag_values): self.flagname = flagname message = "The flag '%s' is defined twice." % self.flagname flags_by_module = flag_values.FlagsByModuleDict() for module in flags_by_module: for flag in flags_by_module[module]: if flag.name == flagname or flag.short_name == flagname: message = message + " First from " + module + "," break message = message + " Second from " + _GetCallingModule() DuplicateFlag.__init__(self, message) class IllegalFlagValue(FlagsError): """The flag command line argument is illegal.""" pass class UnrecognizedFlag(FlagsError): """Raised if a flag is unrecognized.""" pass # An UnrecognizedFlagError conveys more information than an UnrecognizedFlag. # Since there are external modules that create DuplicateFlags, the interface to # DuplicateFlag shouldn't change. The flagvalue will be assigned the full value # of the flag and its argument, if any, allowing handling of unrecognzed flags # in an exception handler. # If flagvalue is the empty string, then this exception is an due to a # reference to a flag that was not already defined. class UnrecognizedFlagError(UnrecognizedFlag): def __init__(self, flagname, flagvalue=''): self.flagname = flagname self.flagvalue = flagvalue UnrecognizedFlag.__init__( self, "Unknown command line flag '%s'" % flagname) # Global variable used by expvar _exported_flags = {} _help_width = 80 # width of help output def GetHelpWidth(): """Returns: an integer, the width of help lines that is used in TextWrap.""" return _help_width def CutCommonSpacePrefix(text): """Removes a common space prefix from the lines of a multiline text. If the first line does not start with a space, it is left as it is and only in the remaining lines a common space prefix is being searched for. That means the first line will stay untouched. This is especially useful to turn doc strings into help texts. This is because some people prefer to have the doc comment start already after the apostrophy and then align the following lines while others have the apostrophies on a seperately line. The function also drops trailing empty lines and ignores empty lines following the initial content line while calculating the initial common whitespace. Args: text: text to work on Returns: the resulting text """ text_lines = text.splitlines() # Drop trailing empty lines while text_lines and not text_lines[-1]: text_lines = text_lines[:-1] if text_lines: # We got some content, is the first line starting with a space? if text_lines[0] and text_lines[0][0].isspace(): text_first_line = [] else: text_first_line = [text_lines.pop(0)] # Calculate length of common leading whitesppace (only over content lines) common_prefix = os.path.commonprefix([line for line in text_lines if line]) space_prefix_len = len(common_prefix) - len(common_prefix.lstrip()) # If we have a common space prefix, drop it from all lines if space_prefix_len: for index in xrange(len(text_lines)): if text_lines[index]: text_lines[index] = text_lines[index][space_prefix_len:] return '\n'.join(text_first_line + text_lines) return '' def TextWrap(text, length=None, indent='', firstline_indent=None, tabs=' '): """Wraps a given text to a maximum line length and returns it. We turn lines that only contain whitespaces into empty lines. We keep new lines and tabs (e.g., we do not treat tabs as spaces). Args: text: text to wrap length: maximum length of a line, includes indentation if this is None then use GetHelpWidth() indent: indent for all but first line firstline_indent: indent for first line; if None, fall back to indent tabs: replacement for tabs Returns: wrapped text Raises: FlagsError: if indent not shorter than length FlagsError: if firstline_indent not shorter than length """ # Get defaults where callee used None if length is None: length = GetHelpWidth() if indent is None: indent = '' if len(indent) >= length: raise FlagsError('Indent must be shorter than length') # In line we will be holding the current line which is to be started # with indent (or firstline_indent if available) and then appended # with words. if firstline_indent is None: firstline_indent = '' line = indent else: line = firstline_indent if len(firstline_indent) >= length: raise FlagsError('First iline indent must be shorter than length') # If the callee does not care about tabs we simply convert them to # spaces If callee wanted tabs to be single space then we do that # already here. if not tabs or tabs == ' ': text = text.replace('\t', ' ') else: tabs_are_whitespace = not tabs.strip() line_regex = re.compile('([ ]*)(\t*)([^ \t]+)', re.MULTILINE) # Split the text into lines and the lines with the regex above. The # resulting lines are collected in result[]. For each split we get the # spaces, the tabs and the next non white space (e.g. next word). result = [] for text_line in text.splitlines(): # Store result length so we can find out whether processing the next # line gave any new content old_result_len = len(result) # Process next line with line_regex. For optimization we do an rstrip(). # - process tabs (changes either line or word, see below) # - process word (first try to squeeze on line, then wrap or force wrap) # Spaces found on the line are ignored, they get added while wrapping as # needed. for spaces, current_tabs, word in line_regex.findall(text_line.rstrip()): # If tabs weren't converted to spaces, handle them now if current_tabs: # If the last thing we added was a space anyway then drop # it. But let's not get rid of the indentation. if (((result and line != indent) or (not result and line != firstline_indent)) and line[-1] == ' '): line = line[:-1] # Add the tabs, if that means adding whitespace, just add it at # the line, the rstrip() code while shorten the line down if # necessary if tabs_are_whitespace: line += tabs * len(current_tabs) else: # if not all tab replacement is whitespace we prepend it to the word word = tabs * len(current_tabs) + word # Handle the case where word cannot be squeezed onto current last line if len(line) + len(word) > length and len(indent) + len(word) <= length: result.append(line.rstrip()) line = indent + word word = '' # No space left on line or can we append a space? if len(line) + 1 >= length: result.append(line.rstrip()) line = indent else: line += ' ' # Add word and shorten it up to allowed line length. Restart next # line with indent and repeat, or add a space if we're done (word # finished) This deals with words that caanot fit on one line # (e.g. indent + word longer than allowed line length). while len(line) + len(word) >= length: line += word result.append(line[:length]) word = line[length:] line = indent # Default case, simply append the word and a space if word: line += word + ' ' # End of input line. If we have content we finish the line. If the # current line is just the indent but we had content in during this # original line then we need to add an emoty line. if (result and line != indent) or (not result and line != firstline_indent): result.append(line.rstrip()) elif len(result) == old_result_len: result.append('') line = indent return '\n'.join(result) def DocToHelp(doc): """Takes a __doc__ string and reformats it as help.""" # Get rid of starting and ending white space. Using lstrip() or even # strip() could drop more than maximum of first line and right space # of last line. doc = doc.strip() # Get rid of all empty lines whitespace_only_line = re.compile('^[ \t]+$', re.M) doc = whitespace_only_line.sub('', doc) # Cut out common space at line beginnings doc = CutCommonSpacePrefix(doc) # Just like this module's comment, comments tend to be aligned somehow. # In other words they all start with the same amount of white space # 1) keep double new lines # 2) keep ws after new lines if not empty line # 3) all other new lines shall be changed to a space # Solution: Match new lines between non white space and replace with space. doc = re.sub('(?<=\S)\n(?=\S)', ' ', doc, re.M) return doc def _GetModuleObjectAndName(globals_dict): """Returns the module that defines a global environment, and its name. Args: globals_dict: A dictionary that should correspond to an environment providing the values of the globals. Returns: A pair consisting of (1) module object and (2) module name (a string). Returns (None, None) if the module could not be identified. """ # The use of .items() (instead of .iteritems()) is NOT a mistake: if # a parallel thread imports a module while we iterate over # .iteritems() (not nice, but possible), we get a RuntimeError ... # Hence, we use the slightly slower but safer .items(). for name, module in sys.modules.items(): if getattr(module, '__dict__', None) is globals_dict: if name == '__main__': # Pick a more informative name for the main module. name = sys.argv[0] return (module, name) return (None, None) def _GetMainModule(): """Returns the name of the module from which execution started.""" for depth in range(1, sys.getrecursionlimit()): try: globals_of_main = sys._getframe(depth).f_globals except ValueError: return _GetModuleObjectAndName(globals_of_main)[1] raise AssertionError("No module was found") class FlagValues: """Registry of 'Flag' objects. A 'FlagValues' can then scan command line arguments, passing flag arguments through to the 'Flag' objects that it owns. It also provides easy access to the flag values. Typically only one 'FlagValues' object is needed by an application: gflags.FLAGS This class is heavily overloaded: 'Flag' objects are registered via __setitem__: FLAGS['longname'] = x # register a new flag The .value attribute of the registered 'Flag' objects can be accessed as attributes of this 'FlagValues' object, through __getattr__. Both the long and short name of the original 'Flag' objects can be used to access its value: FLAGS.longname # parsed flag value FLAGS.x # parsed flag value (short name) Command line arguments are scanned and passed to the registered 'Flag' objects through the __call__ method. Unparsed arguments, including argv[0] (e.g. the program name) are returned. argv = FLAGS(sys.argv) # scan command line arguments The original registered Flag objects can be retrieved through the use of the dictionary-like operator, __getitem__: x = FLAGS['longname'] # access the registered Flag object The str() operator of a 'FlagValues' object provides help for all of the registered 'Flag' objects. """ def __init__(self): # Since everything in this class is so heavily overloaded, the only # way of defining and using fields is to access __dict__ directly. # Dictionary: flag name (string) -> Flag object. self.__dict__['__flags'] = {} # Dictionary: module name (string) -> list of Flag objects that are defined # by that module. self.__dict__['__flags_by_module'] = {} # Dictionary: module name (string) -> list of Flag objects that are # key for that module. self.__dict__['__key_flags_by_module'] = {} # Set if we should use new style gnu_getopt rather than getopt when parsing # the args. Only possible with Python 2.3+ self.UseGnuGetOpt(False) def UseGnuGetOpt(self, use_gnu_getopt=True): self.__dict__['__use_gnu_getopt'] = use_gnu_getopt def IsGnuGetOpt(self): return self.__dict__['__use_gnu_getopt'] def FlagDict(self): return self.__dict__['__flags'] def FlagsByModuleDict(self): """Returns the dictionary of module_name -> list of defined flags. Returns: A dictionary. Its keys are module names (strings). Its values are lists of Flag objects. """ return self.__dict__['__flags_by_module'] def KeyFlagsByModuleDict(self): """Returns the dictionary of module_name -> list of key flags. Returns: A dictionary. Its keys are module names (strings). Its values are lists of Flag objects. """ return self.__dict__['__key_flags_by_module'] def _RegisterFlagByModule(self, module_name, flag): """Records the module that defines a specific flag. We keep track of which flag is defined by which module so that we can later sort the flags by module. Args: module_name: A string, the name of a Python module. flag: A Flag object, a flag that is key to the module. """ flags_by_module = self.FlagsByModuleDict() flags_by_module.setdefault(module_name, []).append(flag) def _RegisterKeyFlagForModule(self, module_name, flag): """Specifies that a flag is a key flag for a module. Args: module_name: A string, the name of a Python module. flag: A Flag object, a flag that is key to the module. """ key_flags_by_module = self.KeyFlagsByModuleDict() # The list of key flags for the module named module_name. key_flags = key_flags_by_module.setdefault(module_name, []) # Add flag, but avoid duplicates. if flag not in key_flags: key_flags.append(flag) def _GetFlagsDefinedByModule(self, module): """Returns the list of flags defined by a module. Args: module: A module object or a module name (a string). Returns: A new list of Flag objects. Caller may update this list as he wishes: none of those changes will affect the internals of this FlagValue object. """ if not isinstance(module, str): module = module.__name__ return list(self.FlagsByModuleDict().get(module, [])) def _GetKeyFlagsForModule(self, module): """Returns the list of key flags for a module. Args: module: A module object or a module name (a string) Returns: A new list of Flag objects. Caller may update this list as he wishes: none of those changes will affect the internals of this FlagValue object. """ if not isinstance(module, str): module = module.__name__ # Any flag is a key flag for the module that defined it. NOTE: # key_flags is a fresh list: we can update it without affecting the # internals of this FlagValues object. key_flags = self._GetFlagsDefinedByModule(module) # Take into account flags explicitly declared as key for a module. for flag in self.KeyFlagsByModuleDict().get(module, []): if flag not in key_flags: key_flags.append(flag) return key_flags def AppendFlagValues(self, flag_values): """Appends flags registered in another FlagValues instance. Args: flag_values: registry to copy from """ for flag_name, flag in flag_values.FlagDict().iteritems(): # Each flags with shortname appears here twice (once under its # normal name, and again with its short name). To prevent # problems (DuplicateFlagError) with double flag registration, we # perform a check to make sure that the entry we're looking at is # for its normal name. if flag_name == flag.name: self[flag_name] = flag def RemoveFlagValues(self, flag_values): """Remove flags that were previously appended from another FlagValues. Args: flag_values: registry containing flags to remove. """ for flag_name in flag_values.FlagDict(): self.__delattr__(flag_name) def __setitem__(self, name, flag): """Registers a new flag variable.""" fl = self.FlagDict() if not isinstance(flag, Flag): raise IllegalFlagValue(flag) if not isinstance(name, type("")): raise FlagsError("Flag name must be a string") if len(name) == 0: raise FlagsError("Flag name cannot be empty") # If running under pychecker, duplicate keys are likely to be # defined. Disable check for duplicate keys when pycheck'ing. if (fl.has_key(name) and not flag.allow_override and not fl[name].allow_override and not _RUNNING_PYCHECKER): raise DuplicateFlagError(name, self) short_name = flag.short_name if short_name is not None: if (fl.has_key(short_name) and not flag.allow_override and not fl[short_name].allow_override and not _RUNNING_PYCHECKER): raise DuplicateFlagError(short_name, self) fl[short_name] = flag fl[name] = flag global _exported_flags _exported_flags[name] = flag def __getitem__(self, name): """Retrieves the Flag object for the flag --name.""" return self.FlagDict()[name] def __getattr__(self, name): """Retrieves the 'value' attribute of the flag --name.""" fl = self.FlagDict() if not fl.has_key(name): raise AttributeError(name) return fl[name].value def __setattr__(self, name, value): """Sets the 'value' attribute of the flag --name.""" fl = self.FlagDict() fl[name].value = value self._AssertValidators(fl[name].validators) return value def _AssertAllValidators(self): all_validators = set() for flag in self.FlagDict().itervalues(): for validator in flag.validators: all_validators.add(validator) self._AssertValidators(all_validators) def _AssertValidators(self, validators): """Assert if all validators in the list are satisfied. Asserts validators in the order they were created. Args: validators: Iterable(gflags_validators.Validator), validators to be verified Raises: AttributeError: if validators work with a non-existing flag. IllegalFlagValue: if validation fails for at least one validator """ for validator in sorted( validators, key=lambda validator: validator.insertion_index): try: validator.Verify(self) except gflags_validators.Error, e: message = validator.PrintFlagsWithValues(self) raise IllegalFlagValue('%s: %s' % (message, str(e))) def _FlagIsRegistered(self, flag_obj): """Checks whether a Flag object is registered under some name. Note: this is non trivial: in addition to its normal name, a flag may have a short name too. In self.FlagDict(), both the normal and the short name are mapped to the same flag object. E.g., calling only "del FLAGS.short_name" is not unregistering the corresponding Flag object (it is still registered under the longer name). Args: flag_obj: A Flag object. Returns: A boolean: True iff flag_obj is registered under some name. """ flag_dict = self.FlagDict() # Check whether flag_obj is registered under its long name. name = flag_obj.name if flag_dict.get(name, None) == flag_obj: return True # Check whether flag_obj is registered under its short name. short_name = flag_obj.short_name if (short_name is not None and flag_dict.get(short_name, None) == flag_obj): return True # The flag cannot be registered under any other name, so we do not # need to do a full search through the values of self.FlagDict(). return False def __delattr__(self, flag_name): """Deletes a previously-defined flag from a flag object. This method makes sure we can delete a flag by using del flag_values_object.<flag_name> E.g., flags.DEFINE_integer('foo', 1, 'Integer flag.') del flags.FLAGS.foo Args: flag_name: A string, the name of the flag to be deleted. Raises: AttributeError: When there is no registered flag named flag_name. """ fl = self.FlagDict() if flag_name not in fl: raise AttributeError(flag_name) flag_obj = fl[flag_name] del fl[flag_name] if not self._FlagIsRegistered(flag_obj): # If the Flag object indicated by flag_name is no longer # registered (please see the docstring of _FlagIsRegistered), then # we delete the occurences of the flag object in all our internal # dictionaries. self.__RemoveFlagFromDictByModule(self.FlagsByModuleDict(), flag_obj) self.__RemoveFlagFromDictByModule(self.KeyFlagsByModuleDict(), flag_obj) def __RemoveFlagFromDictByModule(self, flags_by_module_dict, flag_obj): """Removes a flag object from a module -> list of flags dictionary. Args: flags_by_module_dict: A dictionary that maps module names to lists of flags. flag_obj: A flag object. """ for unused_module, flags_in_module in flags_by_module_dict.iteritems(): # while (as opposed to if) takes care of multiple occurences of a # flag in the list for the same module. while flag_obj in flags_in_module: flags_in_module.remove(flag_obj) def SetDefault(self, name, value): """Changes the default value of the named flag object.""" fl = self.FlagDict() if not fl.has_key(name): raise AttributeError(name) fl[name].SetDefault(value) self._AssertValidators(fl[name].validators) def __contains__(self, name): """Returns True if name is a value (flag) in the dict.""" return name in self.FlagDict() has_key = __contains__ # a synonym for __contains__() def __iter__(self): return self.FlagDict().iterkeys() def __call__(self, argv): """Parses flags from argv; stores parsed flags into this FlagValues object. All unparsed arguments are returned. Flags are parsed using the GNU Program Argument Syntax Conventions, using getopt: http://www.gnu.org/software/libc/manual/html_mono/libc.html#Getopt Args: argv: argument list. Can be of any type that may be converted to a list. Returns: The list of arguments not parsed as options, including argv[0] Raises: FlagsError: on any parsing error """ # Support any sequence type that can be converted to a list argv = list(argv) shortopts = "" longopts = [] fl = self.FlagDict() # This pre parses the argv list for --flagfile=<> options. argv = argv[:1] + self.ReadFlagsFromFiles(argv[1:], force_gnu=False) # Correct the argv to support the google style of passing boolean # parameters. Boolean parameters may be passed by using --mybool, # --nomybool, --mybool=(true|false|1|0). getopt does not support # having options that may or may not have a parameter. We replace # instances of the short form --mybool and --nomybool with their # full forms: --mybool=(true|false). original_argv = list(argv) # list() makes a copy shortest_matches = None for name, flag in fl.items(): if not flag.boolean: continue if shortest_matches is None: # Determine the smallest allowable prefix for all flag names shortest_matches = self.ShortestUniquePrefixes(fl) no_name = 'no' + name prefix = shortest_matches[name] no_prefix = shortest_matches[no_name] # Replace all occurences of this boolean with extended forms for arg_idx in range(1, len(argv)): arg = argv[arg_idx] if arg.find('=') >= 0: continue if arg.startswith('--'+prefix) and ('--'+name).startswith(arg): argv[arg_idx] = ('--%s=true' % name) elif arg.startswith('--'+no_prefix) and ('--'+no_name).startswith(arg): argv[arg_idx] = ('--%s=false' % name) # Loop over all of the flags, building up the lists of short options # and long options that will be passed to getopt. Short options are # specified as a string of letters, each letter followed by a colon # if it takes an argument. Long options are stored in an array of # strings. Each string ends with an '=' if it takes an argument. for name, flag in fl.items(): longopts.append(name + "=") if len(name) == 1: # one-letter option: allow short flag type also shortopts += name if not flag.boolean: shortopts += ":" longopts.append('undefok=') undefok_flags = [] # In case --undefok is specified, loop to pick up unrecognized # options one by one. unrecognized_opts = [] args = argv[1:] while True: try: if self.__dict__['__use_gnu_getopt']: optlist, unparsed_args = getopt.gnu_getopt(args, shortopts, longopts) else: optlist, unparsed_args = getopt.getopt(args, shortopts, longopts) break except getopt.GetoptError, e: if not e.opt or e.opt in fl: # Not an unrecognized option, reraise the exception as a FlagsError raise FlagsError(e) # Remove offender from args and try again for arg_index in range(len(args)): if ((args[arg_index] == '--' + e.opt) or (args[arg_index] == '-' + e.opt) or (args[arg_index].startswith('--' + e.opt + '='))): unrecognized_opts.append((e.opt, args[arg_index])) args = args[0:arg_index] + args[arg_index+1:] break else: # We should have found the option, so we don't expect to get # here. We could assert, but raising the original exception # might work better. raise FlagsError(e) for name, arg in optlist: if name == '--undefok': flag_names = arg.split(',') undefok_flags.extend(flag_names) # For boolean flags, if --undefok=boolflag is specified, then we should # also accept --noboolflag, in addition to --boolflag. # Since we don't know the type of the undefok'd flag, this will affect # non-boolean flags as well. # NOTE: You shouldn't use --undefok=noboolflag, because then we will # accept --nonoboolflag here. We are choosing not to do the conversion # from noboolflag -> boolflag because of the ambiguity that flag names # can start with 'no'. undefok_flags.extend('no' + name for name in flag_names) continue if name.startswith('--'): # long option name = name[2:] short_option = 0 else: # short option name = name[1:] short_option = 1 if fl.has_key(name): flag = fl[name] if flag.boolean and short_option: arg = 1 flag.Parse(arg) # If there were unrecognized options, raise an exception unless # the options were named via --undefok. for opt, value in unrecognized_opts: if opt not in undefok_flags: raise UnrecognizedFlagError(opt, value) if unparsed_args: if self.__dict__['__use_gnu_getopt']: # if using gnu_getopt just return the program name + remainder of argv. ret_val = argv[:1] + unparsed_args else: # unparsed_args becomes the first non-flag detected by getopt to # the end of argv. Because argv may have been modified above, # return original_argv for this region. ret_val = argv[:1] + original_argv[-len(unparsed_args):] else: ret_val = argv[:1] self._AssertAllValidators() return ret_val def Reset(self): """Resets the values to the point before FLAGS(argv) was called.""" for f in self.FlagDict().values(): f.Unparse() def RegisteredFlags(self): """Returns: a list of the names and short names of all registered flags.""" return self.FlagDict().keys() def FlagValuesDict(self): """Returns: a dictionary that maps flag names to flag values.""" flag_values = {} for flag_name in self.RegisteredFlags(): flag = self.FlagDict()[flag_name] flag_values[flag_name] = flag.value return flag_values def __str__(self): """Generates a help string for all known flags.""" return self.GetHelp() def GetHelp(self, prefix=''): """Generates a help string for all known flags.""" helplist = [] flags_by_module = self.FlagsByModuleDict() if flags_by_module: modules = flags_by_module.keys() modules.sort() # Print the help for the main module first, if possible. main_module = _GetMainModule() if main_module in modules: modules.remove(main_module) modules = [main_module] + modules for module in modules: self.__RenderOurModuleFlags(module, helplist) self.__RenderModuleFlags('gflags', _SPECIAL_FLAGS.FlagDict().values(), helplist) else: # Just print one long list of flags. self.__RenderFlagList( self.FlagDict().values() + _SPECIAL_FLAGS.FlagDict().values(), helplist, prefix) return '\n'.join(helplist) def __RenderModuleFlags(self, module, flags, output_lines, prefix=""): """Generates a help string for a given module.""" if not isinstance(module, str): module = module.__name__ output_lines.append('\n%s%s:' % (prefix, module)) self.__RenderFlagList(flags, output_lines, prefix + " ") def __RenderOurModuleFlags(self, module, output_lines, prefix=""): """Generates a help string for a given module.""" flags = self._GetFlagsDefinedByModule(module) if flags: self.__RenderModuleFlags(module, flags, output_lines, prefix) def __RenderOurModuleKeyFlags(self, module, output_lines, prefix=""): """Generates a help string for the key flags of a given module. Args: module: A module object or a module name (a string). output_lines: A list of strings. The generated help message lines will be appended to this list. prefix: A string that is prepended to each generated help line. """ key_flags = self._GetKeyFlagsForModule(module) if key_flags: self.__RenderModuleFlags(module, key_flags, output_lines, prefix) def ModuleHelp(self, module): """Describe the key flags of a module. Args: module: A module object or a module name (a string). Returns: string describing the key flags of a module. """ helplist = [] self.__RenderOurModuleKeyFlags(module, helplist) return '\n'.join(helplist) def MainModuleHelp(self): """Describe the key flags of the main module. Returns: string describing the key flags of a module. """ return self.ModuleHelp(_GetMainModule()) def __RenderFlagList(self, flaglist, output_lines, prefix=" "): fl = self.FlagDict() special_fl = _SPECIAL_FLAGS.FlagDict() flaglist = [(flag.name, flag) for flag in flaglist] flaglist.sort() flagset = {} for (name, flag) in flaglist: # It's possible this flag got deleted or overridden since being # registered in the per-module flaglist. Check now against the # canonical source of current flag information, the FlagDict. if fl.get(name, None) != flag and special_fl.get(name, None) != flag: # a different flag is using this name now continue # only print help once if flagset.has_key(flag): continue flagset[flag] = 1 flaghelp = "" if flag.short_name: flaghelp += "-%s," % flag.short_name if flag.boolean: flaghelp += "--[no]%s" % flag.name + ":" else: flaghelp += "--%s" % flag.name + ":" flaghelp += " " if flag.help: flaghelp += flag.help flaghelp = TextWrap(flaghelp, indent=prefix+" ", firstline_indent=prefix) if flag.default_as_str: flaghelp += "\n" flaghelp += TextWrap("(default: %s)" % flag.default_as_str, indent=prefix+" ") if flag.parser.syntactic_help: flaghelp += "\n" flaghelp += TextWrap("(%s)" % flag.parser.syntactic_help, indent=prefix+" ") output_lines.append(flaghelp) def get(self, name, default): """Returns the value of a flag (if not None) or a default value. Args: name: A string, the name of a flag. default: Default value to use if the flag value is None. """ value = self.__getattr__(name) if value is not None: # Can't do if not value, b/c value might be '0' or "" return value else: return default def ShortestUniquePrefixes(self, fl): """Returns: dictionary; maps flag names to their shortest unique prefix.""" # Sort the list of flag names sorted_flags = [] for name, flag in fl.items(): sorted_flags.append(name) if flag.boolean: sorted_flags.append('no%s' % name) sorted_flags.sort() # For each name in the sorted list, determine the shortest unique # prefix by comparing itself to the next name and to the previous # name (the latter check uses cached info from the previous loop). shortest_matches = {} prev_idx = 0 for flag_idx in range(len(sorted_flags)): curr = sorted_flags[flag_idx] if flag_idx == (len(sorted_flags) - 1): next = None else: next = sorted_flags[flag_idx+1] next_len = len(next) for curr_idx in range(len(curr)): if (next is None or curr_idx >= next_len or curr[curr_idx] != next[curr_idx]): # curr longer than next or no more chars in common shortest_matches[curr] = curr[:max(prev_idx, curr_idx) + 1] prev_idx = curr_idx break else: # curr shorter than (or equal to) next shortest_matches[curr] = curr prev_idx = curr_idx + 1 # next will need at least one more char return shortest_matches def __IsFlagFileDirective(self, flag_string): """Checks whether flag_string contain a --flagfile=<foo> directive.""" if isinstance(flag_string, type("")): if flag_string.startswith('--flagfile='): return 1 elif flag_string == '--flagfile': return 1 elif flag_string.startswith('-flagfile='): return 1 elif flag_string == '-flagfile': return 1 else: return 0 return 0 def ExtractFilename(self, flagfile_str): """Returns filename from a flagfile_str of form -[-]flagfile=filename. The cases of --flagfile foo and -flagfile foo shouldn't be hitting this function, as they are dealt with in the level above this function. """ if flagfile_str.startswith('--flagfile='): return os.path.expanduser((flagfile_str[(len('--flagfile=')):]).strip()) elif flagfile_str.startswith('-flagfile='): return os.path.expanduser((flagfile_str[(len('-flagfile=')):]).strip()) else: raise FlagsError('Hit illegal --flagfile type: %s' % flagfile_str) def __GetFlagFileLines(self, filename, parsed_file_list): """Returns the useful (!=comments, etc) lines from a file with flags. Args: filename: A string, the name of the flag file. parsed_file_list: A list of the names of the files we have already read. MUTATED BY THIS FUNCTION. Returns: List of strings. See the note below. NOTE(springer): This function checks for a nested --flagfile=<foo> tag and handles the lower file recursively. It returns a list of all the lines that _could_ contain command flags. This is EVERYTHING except whitespace lines and comments (lines starting with '#' or '//'). """ line_list = [] # All line from flagfile. flag_line_list = [] # Subset of lines w/o comments, blanks, flagfile= tags. try: file_obj = open(filename, 'r') except IOError, e_msg: print e_msg print 'ERROR:: Unable to open flagfile: %s' % (filename) return flag_line_list line_list = file_obj.readlines() file_obj.close() parsed_file_list.append(filename) # This is where we check each line in the file we just read. for line in line_list: if line.isspace(): pass # Checks for comment (a line that starts with '#'). elif line.startswith('#') or line.startswith('//'): pass # Checks for a nested "--flagfile=<bar>" flag in the current file. # If we find one, recursively parse down into that file. elif self.__IsFlagFileDirective(line): sub_filename = self.ExtractFilename(line) # We do a little safety check for reparsing a file we've already done. if not sub_filename in parsed_file_list: included_flags = self.__GetFlagFileLines(sub_filename, parsed_file_list) flag_line_list.extend(included_flags) else: # Case of hitting a circularly included file. print >>sys.stderr, ('Warning: Hit circular flagfile dependency: %s' % sub_filename) else: # Any line that's not a comment or a nested flagfile should get # copied into 2nd position. This leaves earlier arguements # further back in the list, thus giving them higher priority. flag_line_list.append(line.strip()) return flag_line_list def ReadFlagsFromFiles(self, argv, force_gnu=True): """Processes command line args, but also allow args to be read from file. Args: argv: A list of strings, usually sys.argv[1:], which may contain one or more flagfile directives of the form --flagfile="./filename". Note that the name of the program (sys.argv[0]) should be omitted. force_gnu: If False, --flagfile parsing obeys normal flag semantics. If True, --flagfile parsing instead follows gnu_getopt semantics. *** WARNING *** force_gnu=False may become the future default! Returns: A new list which has the original list combined with what we read from any flagfile(s). References: Global gflags.FLAG class instance. This function should be called before the normal FLAGS(argv) call. This function scans the input list for a flag that looks like: --flagfile=<somefile>. Then it opens <somefile>, reads all valid key and value pairs and inserts them into the input list between the first item of the list and any subsequent items in the list. Note that your application's flags are still defined the usual way using gflags DEFINE_flag() type functions. Notes (assuming we're getting a commandline of some sort as our input): --> Flags from the command line argv _should_ always take precedence! --> A further "--flagfile=<otherfile.cfg>" CAN be nested in a flagfile. It will be processed after the parent flag file is done. --> For duplicate flags, first one we hit should "win". --> In a flagfile, a line beginning with # or // is a comment. --> Entirely blank lines _should_ be ignored. """ parsed_file_list = [] rest_of_args = argv new_argv = [] while rest_of_args: current_arg = rest_of_args[0] rest_of_args = rest_of_args[1:] if self.__IsFlagFileDirective(current_arg): # This handles the case of -(-)flagfile foo. In this case the # next arg really is part of this one. if current_arg == '--flagfile' or current_arg == '-flagfile': if not rest_of_args: raise IllegalFlagValue('--flagfile with no argument') flag_filename = os.path.expanduser(rest_of_args[0]) rest_of_args = rest_of_args[1:] else: # This handles the case of (-)-flagfile=foo. flag_filename = self.ExtractFilename(current_arg) new_argv[0:0] = self.__GetFlagFileLines(flag_filename, parsed_file_list) else: new_argv.append(current_arg) # Stop parsing after '--', like getopt and gnu_getopt. if current_arg == '--': break # Stop parsing after a non-flag, like getopt. if not current_arg.startswith('-'): if not force_gnu and not self.__dict__['__use_gnu_getopt']: break if rest_of_args: new_argv.extend(rest_of_args) return new_argv def FlagsIntoString(self): """Returns a string with the flags assignments from this FlagValues object. This function ignores flags whose value is None. Each flag assignment is separated by a newline. NOTE: MUST mirror the behavior of the C++ function CommandlineFlagsIntoString from google3/base/commandlineflags.cc. """ s = '' for flag in self.FlagDict().values(): if flag.value is not None: s += flag.Serialize() + '\n' return s def AppendFlagsIntoFile(self, filename): """Appends all flags assignments from this FlagInfo object to a file. Output will be in the format of a flagfile. NOTE: MUST mirror the behavior of the C++ version of AppendFlagsIntoFile from google3/base/commandlineflags.cc. """ out_file = open(filename, 'a') out_file.write(self.FlagsIntoString()) out_file.close() def WriteHelpInXMLFormat(self, outfile=None): """Outputs flag documentation in XML format. NOTE: We use element names that are consistent with those used by the C++ command-line flag library, from google3/base/commandlineflags_reporting.cc. We also use a few new elements (e.g., <key>), but we do not interfere / overlap with existing XML elements used by the C++ library. Please maintain this consistency. Args: outfile: File object we write to. Default None means sys.stdout. """ outfile = outfile or sys.stdout outfile.write('<?xml version=\"1.0\"?>\n') outfile.write('<AllFlags>\n') indent = ' ' _WriteSimpleXMLElement(outfile, 'program', os.path.basename(sys.argv[0]), indent) usage_doc = sys.modules['__main__'].__doc__ if not usage_doc: usage_doc = '\nUSAGE: %s [flags]\n' % sys.argv[0] else: usage_doc = usage_doc.replace('%s', sys.argv[0]) _WriteSimpleXMLElement(outfile, 'usage', usage_doc, indent) # Get list of key flags for the main module. key_flags = self._GetKeyFlagsForModule(_GetMainModule()) # Sort flags by declaring module name and next by flag name. flags_by_module = self.FlagsByModuleDict() all_module_names = list(flags_by_module.keys()) all_module_names.sort() for module_name in all_module_names: flag_list = [(f.name, f) for f in flags_by_module[module_name]] flag_list.sort() for unused_flag_name, flag in flag_list: is_key = flag in key_flags flag.WriteInfoInXMLFormat(outfile, module_name, is_key=is_key, indent=indent) outfile.write('</AllFlags>\n') outfile.flush() def AddValidator(self, validator): """Register new flags validator to be checked. Args: validator: gflags_validators.Validator Raises: AttributeError: if validators work with a non-existing flag. """ for flag_name in validator.GetFlagsNames(): flag = self.FlagDict()[flag_name] flag.validators.append(validator) # end of FlagValues definition # The global FlagValues instance FLAGS = FlagValues() def _MakeXMLSafe(s): """Escapes <, >, and & from s, and removes XML 1.0-illegal chars.""" s = cgi.escape(s) # Escape <, >, and & # Remove characters that cannot appear in an XML 1.0 document # (http://www.w3.org/TR/REC-xml/#charsets). # # NOTE: if there are problems with current solution, one may move to # XML 1.1, which allows such chars, if they're entity-escaped (&#xHH;). s = re.sub(r'[\x00-\x08\x0b\x0c\x0e-\x1f]', '', s) return s def _WriteSimpleXMLElement(outfile, name, value, indent): """Writes a simple XML element. Args: outfile: File object we write the XML element to. name: A string, the name of XML element. value: A Python object, whose string representation will be used as the value of the XML element. indent: A string, prepended to each line of generated output. """ value_str = str(value) if isinstance(value, bool): # Display boolean values as the C++ flag library does: no caps. value_str = value_str.lower() outfile.write('%s<%s>%s</%s>\n' % (indent, name, _MakeXMLSafe(value_str), name)) class Flag: """Information about a command-line flag. 'Flag' objects define the following fields: .name - the name for this flag .default - the default value for this flag .default_as_str - default value as repr'd string, e.g., "'true'" (or None) .value - the most recent parsed value of this flag; set by Parse() .help - a help string or None if no help is available .short_name - the single letter alias for this flag (or None) .boolean - if 'true', this flag does not accept arguments .present - true if this flag was parsed from command line flags. .parser - an ArgumentParser object .serializer - an ArgumentSerializer object .allow_override - the flag may be redefined without raising an error The only public method of a 'Flag' object is Parse(), but it is typically only called by a 'FlagValues' object. The Parse() method is a thin wrapper around the 'ArgumentParser' Parse() method. The parsed value is saved in .value, and the .present attribute is updated. If this flag was already present, a FlagsError is raised. Parse() is also called during __init__ to parse the default value and initialize the .value attribute. This enables other python modules to safely use flags even if the __main__ module neglects to parse the command line arguments. The .present attribute is cleared after __init__ parsing. If the default value is set to None, then the __init__ parsing step is skipped and the .value attribute is initialized to None. Note: The default value is also presented to the user in the help string, so it is important that it be a legal value for this flag. """ def __init__(self, parser, serializer, name, default, help_string, short_name=None, boolean=0, allow_override=0): self.name = name if not help_string: help_string = '(no help available)' self.help = help_string self.short_name = short_name self.boolean = boolean self.present = 0 self.parser = parser self.serializer = serializer self.allow_override = allow_override self.value = None self.validators = [] self.SetDefault(default) def __GetParsedValueAsString(self, value): if value is None: return None if self.serializer: return repr(self.serializer.Serialize(value)) if self.boolean: if value: return repr('true') else: return repr('false') return repr(str(value)) def Parse(self, argument): try: self.value = self.parser.Parse(argument) except ValueError, e: # recast ValueError as IllegalFlagValue raise IllegalFlagValue("flag --%s=%s: %s" % (self.name, argument, e)) self.present += 1 def Unparse(self): if self.default is None: self.value = None else: self.Parse(self.default) self.present = 0 def Serialize(self): if self.value is None: return '' if self.boolean: if self.value: return "--%s" % self.name else: return "--no%s" % self.name else: if not self.serializer: raise FlagsError("Serializer not present for flag %s" % self.name) return "--%s=%s" % (self.name, self.serializer.Serialize(self.value)) def SetDefault(self, value): """Changes the default value (and current value too) for this Flag.""" # We can't allow a None override because it may end up not being # passed to C++ code when we're overriding C++ flags. So we # cowardly bail out until someone fixes the semantics of trying to # pass None to a C++ flag. See swig_flags.Init() for details on # this behavior. # TODO(olexiy): Users can directly call this method, bypassing all flags # validators (we don't have FlagValues here, so we can not check # validators). # The simplest solution I see is to make this method private. # Another approach would be to store reference to the corresponding # FlagValues with each flag, but this seems to be an overkill. if value is None and self.allow_override: raise DuplicateFlagCannotPropagateNoneToSwig(self.name) self.default = value self.Unparse() self.default_as_str = self.__GetParsedValueAsString(self.value) def Type(self): """Returns: a string that describes the type of this Flag.""" # NOTE: we use strings, and not the types.*Type constants because # our flags can have more exotic types, e.g., 'comma separated list # of strings', 'whitespace separated list of strings', etc. return self.parser.Type() def WriteInfoInXMLFormat(self, outfile, module_name, is_key=False, indent=''): """Writes common info about this flag, in XML format. This is information that is relevant to all flags (e.g., name, meaning, etc.). If you defined a flag that has some other pieces of info, then please override _WriteCustomInfoInXMLFormat. Please do NOT override this method. Args: outfile: File object we write to. module_name: A string, the name of the module that defines this flag. is_key: A boolean, True iff this flag is key for main module. indent: A string that is prepended to each generated line. """ outfile.write(indent + '<flag>\n') inner_indent = indent + ' ' if is_key: _WriteSimpleXMLElement(outfile, 'key', 'yes', inner_indent) _WriteSimpleXMLElement(outfile, 'file', module_name, inner_indent) # Print flag features that are relevant for all flags. _WriteSimpleXMLElement(outfile, 'name', self.name, inner_indent) if self.short_name: _WriteSimpleXMLElement(outfile, 'short_name', self.short_name, inner_indent) if self.help: _WriteSimpleXMLElement(outfile, 'meaning', self.help, inner_indent) # The default flag value can either be represented as a string like on the # command line, or as a Python object. We serialize this value in the # latter case in order to remain consistent. if self.serializer and not isinstance(self.default, str): default_serialized = self.serializer.Serialize(self.default) else: default_serialized = self.default _WriteSimpleXMLElement(outfile, 'default', default_serialized, inner_indent) _WriteSimpleXMLElement(outfile, 'current', self.value, inner_indent) _WriteSimpleXMLElement(outfile, 'type', self.Type(), inner_indent) # Print extra flag features this flag may have. self._WriteCustomInfoInXMLFormat(outfile, inner_indent) outfile.write(indent + '</flag>\n') def _WriteCustomInfoInXMLFormat(self, outfile, indent): """Writes extra info about this flag, in XML format. "Extra" means "not already printed by WriteInfoInXMLFormat above." Args: outfile: File object we write to. indent: A string that is prepended to each generated line. """ # Usually, the parser knows the extra details about the flag, so # we just forward the call to it. self.parser.WriteCustomInfoInXMLFormat(outfile, indent) # End of Flag definition class _ArgumentParserCache(type): """Metaclass used to cache and share argument parsers among flags.""" _instances = {} def __call__(mcs, *args, **kwargs): """Returns an instance of the argument parser cls. This method overrides behavior of the __new__ methods in all subclasses of ArgumentParser (inclusive). If an instance for mcs with the same set of arguments exists, this instance is returned, otherwise a new instance is created. If any keyword arguments are defined, or the values in args are not hashable, this method always returns a new instance of cls. Args: args: Positional initializer arguments. kwargs: Initializer keyword arguments. Returns: An instance of cls, shared or new. """ if kwargs: return type.__call__(mcs, *args, **kwargs) else: instances = mcs._instances key = (mcs,) + tuple(args) try: return instances[key] except KeyError: # No cache entry for key exists, create a new one. return instances.setdefault(key, type.__call__(mcs, *args)) except TypeError: # An object in args cannot be hashed, always return # a new instance. return type.__call__(mcs, *args) class ArgumentParser(object): """Base class used to parse and convert arguments. The Parse() method checks to make sure that the string argument is a legal value and convert it to a native type. If the value cannot be converted, it should throw a 'ValueError' exception with a human readable explanation of why the value is illegal. Subclasses should also define a syntactic_help string which may be presented to the user to describe the form of the legal values. Argument parser classes must be stateless, since instances are cached and shared between flags. Initializer arguments are allowed, but all member variables must be derived from initializer arguments only. """ __metaclass__ = _ArgumentParserCache syntactic_help = "" def Parse(self, argument): """Default implementation: always returns its argument unmodified.""" return argument def Type(self): return 'string' def WriteCustomInfoInXMLFormat(self, outfile, indent): pass class ArgumentSerializer: """Base class for generating string representations of a flag value.""" def Serialize(self, value): return str(value) class ListSerializer(ArgumentSerializer): def __init__(self, list_sep): self.list_sep = list_sep def Serialize(self, value): return self.list_sep.join([str(x) for x in value]) # Flags validators def RegisterValidator(flag_name, checker, message='Flag validation failed', flag_values=FLAGS): """Adds a constraint, which will be enforced during program execution. The constraint is validated when flags are initially parsed, and after each change of the corresponding flag's value. Args: flag_name: string, name of the flag to be checked. checker: method to validate the flag. input - value of the corresponding flag (string, boolean, etc. This value will be passed to checker by the library). See file's docstring for examples. output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise gflags_validators.Error(desired_error_message). message: error text to be shown to the user if checker returns False. If checker raises gflags_validators.Error, message from the raised Error will be shown. flag_values: FlagValues Raises: AttributeError: if flag_name is not registered as a valid flag name. """ flag_values.AddValidator(gflags_validators.SimpleValidator(flag_name, checker, message)) def MarkFlagAsRequired(flag_name, flag_values=FLAGS): """Ensure that flag is not None during program execution. Registers a flag validator, which will follow usual validator rules. Args: flag_name: string, name of the flag flag_values: FlagValues Raises: AttributeError: if flag_name is not registered as a valid flag name. """ RegisterValidator(flag_name, lambda value: value is not None, message='Flag --%s must be specified.' % flag_name, flag_values=flag_values) def _RegisterBoundsValidatorIfNeeded(parser, name, flag_values): """Enforce lower and upper bounds for numeric flags. Args: parser: NumericParser (either FloatParser or IntegerParser). Provides lower and upper bounds, and help text to display. name: string, name of the flag flag_values: FlagValues """ if parser.lower_bound is not None or parser.upper_bound is not None: def Checker(value): if value is not None and parser.IsOutsideBounds(value): message = '%s is not %s' % (value, parser.syntactic_help) raise gflags_validators.Error(message) return True RegisterValidator(name, Checker, flag_values=flag_values) # The DEFINE functions are explained in mode details in the module doc string. def DEFINE(parser, name, default, help, flag_values=FLAGS, serializer=None, **args): """Registers a generic Flag object. NOTE: in the docstrings of all DEFINE* functions, "registers" is short for "creates a new flag and registers it". Auxiliary function: clients should use the specialized DEFINE_<type> function instead. Args: parser: ArgumentParser that is used to parse the flag arguments. name: A string, the flag name. default: The default value of the flag. help: A help string. flag_values: FlagValues object the flag will be registered with. serializer: ArgumentSerializer that serializes the flag value. args: Dictionary with extra keyword args that are passes to the Flag __init__. """ DEFINE_flag(Flag(parser, serializer, name, default, help, **args), flag_values) def DEFINE_flag(flag, flag_values=FLAGS): """Registers a 'Flag' object with a 'FlagValues' object. By default, the global FLAGS 'FlagValue' object is used. Typical users will use one of the more specialized DEFINE_xxx functions, such as DEFINE_string or DEFINE_integer. But developers who need to create Flag objects themselves should use this function to register their flags. """ # copying the reference to flag_values prevents pychecker warnings fv = flag_values fv[flag.name] = flag # Tell flag_values who's defining the flag. if isinstance(flag_values, FlagValues): # Regarding the above isinstance test: some users pass funny # values of flag_values (e.g., {}) in order to avoid the flag # registration (in the past, there used to be a flag_values == # FLAGS test here) and redefine flags with the same name (e.g., # debug). To avoid breaking their code, we perform the # registration only if flag_values is a real FlagValues object. flag_values._RegisterFlagByModule(_GetCallingModule(), flag) def _InternalDeclareKeyFlags(flag_names, flag_values=FLAGS, key_flag_values=None): """Declares a flag as key for the calling module. Internal function. User code should call DECLARE_key_flag or ADOPT_module_key_flags instead. Args: flag_names: A list of strings that are names of already-registered Flag objects. flag_values: A FlagValues object that the flags listed in flag_names have registered with (the value of the flag_values argument from the DEFINE_* calls that defined those flags). This should almost never need to be overridden. key_flag_values: A FlagValues object that (among possibly many other things) keeps track of the key flags for each module. Default None means "same as flag_values". This should almost never need to be overridden. Raises: UnrecognizedFlagError: when we refer to a flag that was not defined yet. """ key_flag_values = key_flag_values or flag_values module = _GetCallingModule() for flag_name in flag_names: if flag_name not in flag_values: raise UnrecognizedFlagError(flag_name) flag = flag_values.FlagDict()[flag_name] key_flag_values._RegisterKeyFlagForModule(module, flag) def DECLARE_key_flag(flag_name, flag_values=FLAGS): """Declares one flag as key to the current module. Key flags are flags that are deemed really important for a module. They are important when listing help messages; e.g., if the --helpshort command-line flag is used, then only the key flags of the main module are listed (instead of all flags, as in the case of --help). Sample usage: flags.DECLARED_key_flag('flag_1') Args: flag_name: A string, the name of an already declared flag. (Redeclaring flags as key, including flags implicitly key because they were declared in this module, is a no-op.) flag_values: A FlagValues object. This should almost never need to be overridden. """ if flag_name in _SPECIAL_FLAGS: # Take care of the special flags, e.g., --flagfile, --undefok. # These flags are defined in _SPECIAL_FLAGS, and are treated # specially during flag parsing, taking precedence over the # user-defined flags. _InternalDeclareKeyFlags([flag_name], flag_values=_SPECIAL_FLAGS, key_flag_values=flag_values) return _InternalDeclareKeyFlags([flag_name], flag_values=flag_values) def ADOPT_module_key_flags(module, flag_values=FLAGS): """Declares that all flags key to a module are key to the current module. Args: module: A module object. flag_values: A FlagValues object. This should almost never need to be overridden. Raises: FlagsError: When given an argument that is a module name (a string), instead of a module object. """ # NOTE(salcianu): an even better test would be if not # isinstance(module, types.ModuleType) but I didn't want to import # types for such a tiny use. if isinstance(module, str): raise FlagsError('Received module name %s; expected a module object.' % module) _InternalDeclareKeyFlags( [f.name for f in flag_values._GetKeyFlagsForModule(module.__name__)], flag_values=flag_values) # If module is this flag module, take _SPECIAL_FLAGS into account. if module == _GetThisModuleObjectAndName()[0]: _InternalDeclareKeyFlags( # As we associate flags with _GetCallingModule(), the special # flags defined in this module are incorrectly registered with # a different module. So, we can't use _GetKeyFlagsForModule. # Instead, we take all flags from _SPECIAL_FLAGS (a private # FlagValues, where no other module should register flags). [f.name for f in _SPECIAL_FLAGS.FlagDict().values()], flag_values=_SPECIAL_FLAGS, key_flag_values=flag_values) # # STRING FLAGS # def DEFINE_string(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value can be any string.""" parser = ArgumentParser() serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) # # BOOLEAN FLAGS # # and the special HELP flags. class BooleanParser(ArgumentParser): """Parser of boolean values.""" def Convert(self, argument): """Converts the argument to a boolean; raise ValueError on errors.""" if type(argument) == str: if argument.lower() in ['true', 't', '1']: return True elif argument.lower() in ['false', 'f', '0']: return False bool_argument = bool(argument) if argument == bool_argument: # The argument is a valid boolean (True, False, 0, or 1), and not just # something that always converts to bool (list, string, int, etc.). return bool_argument raise ValueError('Non-boolean argument to boolean flag', argument) def Parse(self, argument): val = self.Convert(argument) return val def Type(self): return 'bool' class BooleanFlag(Flag): """Basic boolean flag. Boolean flags do not take any arguments, and their value is either True (1) or False (0). The false value is specified on the command line by prepending the word 'no' to either the long or the short flag name. For example, if a Boolean flag was created whose long name was 'update' and whose short name was 'x', then this flag could be explicitly unset through either --noupdate or --nox. """ def __init__(self, name, default, help, short_name=None, **args): p = BooleanParser() Flag.__init__(self, p, None, name, default, help, short_name, 1, **args) if not self.help: self.help = "a boolean value" def DEFINE_boolean(name, default, help, flag_values=FLAGS, **args): """Registers a boolean flag. Such a boolean flag does not take an argument. If a user wants to specify a false value explicitly, the long option beginning with 'no' must be used: i.e. --noflag This flag will have a value of None, True or False. None is possible if default=None and the user does not specify the flag on the command line. """ DEFINE_flag(BooleanFlag(name, default, help, **args), flag_values) # Match C++ API to unconfuse C++ people. DEFINE_bool = DEFINE_boolean class HelpFlag(BooleanFlag): """ HelpFlag is a special boolean flag that prints usage information and raises a SystemExit exception if it is ever found in the command line arguments. Note this is called with allow_override=1, so other apps can define their own --help flag, replacing this one, if they want. """ def __init__(self): BooleanFlag.__init__(self, "help", 0, "show this help", short_name="?", allow_override=1) def Parse(self, arg): if arg: doc = sys.modules["__main__"].__doc__ flags = str(FLAGS) print doc or ("\nUSAGE: %s [flags]\n" % sys.argv[0]) if flags: print "flags:" print flags sys.exit(1) class HelpXMLFlag(BooleanFlag): """Similar to HelpFlag, but generates output in XML format.""" def __init__(self): BooleanFlag.__init__(self, 'helpxml', False, 'like --help, but generates XML output', allow_override=1) def Parse(self, arg): if arg: FLAGS.WriteHelpInXMLFormat(sys.stdout) sys.exit(1) class HelpshortFlag(BooleanFlag): """ HelpshortFlag is a special boolean flag that prints usage information for the "main" module, and rasies a SystemExit exception if it is ever found in the command line arguments. Note this is called with allow_override=1, so other apps can define their own --helpshort flag, replacing this one, if they want. """ def __init__(self): BooleanFlag.__init__(self, "helpshort", 0, "show usage only for this module", allow_override=1) def Parse(self, arg): if arg: doc = sys.modules["__main__"].__doc__ flags = FLAGS.MainModuleHelp() print doc or ("\nUSAGE: %s [flags]\n" % sys.argv[0]) if flags: print "flags:" print flags sys.exit(1) # # Numeric parser - base class for Integer and Float parsers # class NumericParser(ArgumentParser): """Parser of numeric values. Parsed value may be bounded to a given upper and lower bound. """ def IsOutsideBounds(self, val): return ((self.lower_bound is not None and val < self.lower_bound) or (self.upper_bound is not None and val > self.upper_bound)) def Parse(self, argument): val = self.Convert(argument) if self.IsOutsideBounds(val): raise ValueError("%s is not %s" % (val, self.syntactic_help)) return val def WriteCustomInfoInXMLFormat(self, outfile, indent): if self.lower_bound is not None: _WriteSimpleXMLElement(outfile, 'lower_bound', self.lower_bound, indent) if self.upper_bound is not None: _WriteSimpleXMLElement(outfile, 'upper_bound', self.upper_bound, indent) def Convert(self, argument): """Default implementation: always returns its argument unmodified.""" return argument # End of Numeric Parser # # FLOAT FLAGS # class FloatParser(NumericParser): """Parser of floating point values. Parsed value may be bounded to a given upper and lower bound. """ number_article = "a" number_name = "number" syntactic_help = " ".join((number_article, number_name)) def __init__(self, lower_bound=None, upper_bound=None): super(FloatParser, self).__init__() self.lower_bound = lower_bound self.upper_bound = upper_bound sh = self.syntactic_help if lower_bound is not None and upper_bound is not None: sh = ("%s in the range [%s, %s]" % (sh, lower_bound, upper_bound)) elif lower_bound == 0: sh = "a non-negative %s" % self.number_name elif upper_bound == 0: sh = "a non-positive %s" % self.number_name elif upper_bound is not None: sh = "%s <= %s" % (self.number_name, upper_bound) elif lower_bound is not None: sh = "%s >= %s" % (self.number_name, lower_bound) self.syntactic_help = sh def Convert(self, argument): """Converts argument to a float; raises ValueError on errors.""" return float(argument) def Type(self): return 'float' # End of FloatParser def DEFINE_float(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value must be a float. If lower_bound or upper_bound are set, then this flag must be within the given range. """ parser = FloatParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) _RegisterBoundsValidatorIfNeeded(parser, name, flag_values=flag_values) # # INTEGER FLAGS # class IntegerParser(NumericParser): """Parser of an integer value. Parsed value may be bounded to a given upper and lower bound. """ number_article = "an" number_name = "integer" syntactic_help = " ".join((number_article, number_name)) def __init__(self, lower_bound=None, upper_bound=None): super(IntegerParser, self).__init__() self.lower_bound = lower_bound self.upper_bound = upper_bound sh = self.syntactic_help if lower_bound is not None and upper_bound is not None: sh = ("%s in the range [%s, %s]" % (sh, lower_bound, upper_bound)) elif lower_bound == 1: sh = "a positive %s" % self.number_name elif upper_bound == -1: sh = "a negative %s" % self.number_name elif lower_bound == 0: sh = "a non-negative %s" % self.number_name elif upper_bound == 0: sh = "a non-positive %s" % self.number_name elif upper_bound is not None: sh = "%s <= %s" % (self.number_name, upper_bound) elif lower_bound is not None: sh = "%s >= %s" % (self.number_name, lower_bound) self.syntactic_help = sh def Convert(self, argument): __pychecker__ = 'no-returnvalues' if type(argument) == str: base = 10 if len(argument) > 2 and argument[0] == "0" and argument[1] == "x": base = 16 try: return int(argument, base) # ValueError is thrown when argument is a string, and overflows an int. except ValueError: return long(argument, base) else: try: return int(argument) # OverflowError is thrown when argument is numeric, and overflows an int. except OverflowError: return long(argument) def Type(self): return 'int' def DEFINE_integer(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value must be an integer. If lower_bound, or upper_bound are set, then this flag must be within the given range. """ parser = IntegerParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) _RegisterBoundsValidatorIfNeeded(parser, name, flag_values=flag_values) # # ENUM FLAGS # class EnumParser(ArgumentParser): """Parser of a string enum value (a string value from a given set). If enum_values (see below) is not specified, any string is allowed. """ def __init__(self, enum_values=None): super(EnumParser, self).__init__() self.enum_values = enum_values def Parse(self, argument): if self.enum_values and argument not in self.enum_values: raise ValueError("value should be one of <%s>" % "|".join(self.enum_values)) return argument def Type(self): return 'string enum' class EnumFlag(Flag): """Basic enum flag; its value can be any string from list of enum_values.""" def __init__(self, name, default, help, enum_values=None, short_name=None, **args): enum_values = enum_values or [] p = EnumParser(enum_values) g = ArgumentSerializer() Flag.__init__(self, p, g, name, default, help, short_name, **args) if not self.help: self.help = "an enum string" self.help = "<%s>: %s" % ("|".join(enum_values), self.help) def _WriteCustomInfoInXMLFormat(self, outfile, indent): for enum_value in self.parser.enum_values: _WriteSimpleXMLElement(outfile, 'enum_value', enum_value, indent) def DEFINE_enum(name, default, enum_values, help, flag_values=FLAGS, **args): """Registers a flag whose value can be any string from enum_values.""" DEFINE_flag(EnumFlag(name, default, help, enum_values, ** args), flag_values) # # LIST FLAGS # class BaseListParser(ArgumentParser): """Base class for a parser of lists of strings. To extend, inherit from this class; from the subclass __init__, call BaseListParser.__init__(self, token, name) where token is a character used to tokenize, and name is a description of the separator. """ def __init__(self, token=None, name=None): assert name super(BaseListParser, self).__init__() self._token = token self._name = name self.syntactic_help = "a %s separated list" % self._name def Parse(self, argument): if isinstance(argument, list): return argument elif argument == '': return [] else: return [s.strip() for s in argument.split(self._token)] def Type(self): return '%s separated list of strings' % self._name class ListParser(BaseListParser): """Parser for a comma-separated list of strings.""" def __init__(self): BaseListParser.__init__(self, ',', 'comma') def WriteCustomInfoInXMLFormat(self, outfile, indent): BaseListParser.WriteCustomInfoInXMLFormat(self, outfile, indent) _WriteSimpleXMLElement(outfile, 'list_separator', repr(','), indent) class WhitespaceSeparatedListParser(BaseListParser): """Parser for a whitespace-separated list of strings.""" def __init__(self): BaseListParser.__init__(self, None, 'whitespace') def WriteCustomInfoInXMLFormat(self, outfile, indent): BaseListParser.WriteCustomInfoInXMLFormat(self, outfile, indent) separators = list(string.whitespace) separators.sort() for ws_char in string.whitespace: _WriteSimpleXMLElement(outfile, 'list_separator', repr(ws_char), indent) def DEFINE_list(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value is a comma-separated list of strings.""" parser = ListParser() serializer = ListSerializer(',') DEFINE(parser, name, default, help, flag_values, serializer, **args) def DEFINE_spaceseplist(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value is a whitespace-separated list of strings. Any whitespace can be used as a separator. """ parser = WhitespaceSeparatedListParser() serializer = ListSerializer(' ') DEFINE(parser, name, default, help, flag_values, serializer, **args) # # MULTI FLAGS # class MultiFlag(Flag): """A flag that can appear multiple time on the command-line. The value of such a flag is a list that contains the individual values from all the appearances of that flag on the command-line. See the __doc__ for Flag for most behavior of this class. Only differences in behavior are described here: * The default value may be either a single value or a list of values. A single value is interpreted as the [value] singleton list. * The value of the flag is always a list, even if the option was only supplied once, and even if the default value is a single value """ def __init__(self, *args, **kwargs): Flag.__init__(self, *args, **kwargs) self.help += ';\n repeat this option to specify a list of values' def Parse(self, arguments): """Parses one or more arguments with the installed parser. Args: arguments: a single argument or a list of arguments (typically a list of default values); a single argument is converted internally into a list containing one item. """ if not isinstance(arguments, list): # Default value may be a list of values. Most other arguments # will not be, so convert them into a single-item list to make # processing simpler below. arguments = [arguments] if self.present: # keep a backup reference to list of previously supplied option values values = self.value else: # "erase" the defaults with an empty list values = [] for item in arguments: # have Flag superclass parse argument, overwriting self.value reference Flag.Parse(self, item) # also increments self.present values.append(self.value) # put list of option values back in the 'value' attribute self.value = values def Serialize(self): if not self.serializer: raise FlagsError("Serializer not present for flag %s" % self.name) if self.value is None: return '' s = '' multi_value = self.value for self.value in multi_value: if s: s += ' ' s += Flag.Serialize(self) self.value = multi_value return s def Type(self): return 'multi ' + self.parser.Type() def DEFINE_multi(parser, serializer, name, default, help, flag_values=FLAGS, **args): """Registers a generic MultiFlag that parses its args with a given parser. Auxiliary function. Normal users should NOT use it directly. Developers who need to create their own 'Parser' classes for options which can appear multiple times can call this module function to register their flags. """ DEFINE_flag(MultiFlag(parser, serializer, name, default, help, **args), flag_values) def DEFINE_multistring(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value can be a list of any strings. Use the flag on the command line multiple times to place multiple string values into the list. The 'default' may be a single string (which will be converted into a single-element list) or a list of strings. """ parser = ArgumentParser() serializer = ArgumentSerializer() DEFINE_multi(parser, serializer, name, default, help, flag_values, **args) def DEFINE_multi_int(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value can be a list of arbitrary integers. Use the flag on the command line multiple times to place multiple integer values into the list. The 'default' may be a single integer (which will be converted into a single-element list) or a list of integers. """ parser = IntegerParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE_multi(parser, serializer, name, default, help, flag_values, **args) # Now register the flags that we want to exist in all applications. # These are all defined with allow_override=1, so user-apps can use # these flagnames for their own purposes, if they want. DEFINE_flag(HelpFlag()) DEFINE_flag(HelpshortFlag()) DEFINE_flag(HelpXMLFlag()) # Define special flags here so that help may be generated for them. # NOTE: Please do NOT use _SPECIAL_FLAGS from outside this module. _SPECIAL_FLAGS = FlagValues() DEFINE_string( 'flagfile', "", "Insert flag definitions from the given file into the command line.", _SPECIAL_FLAGS) DEFINE_string( 'undefok', "", "comma-separated list of flag names that it is okay to specify " "on the command line even if the program does not define a flag " "with that name. IMPORTANT: flags in this list that have " "arguments MUST use the --flag=value format.", _SPECIAL_FLAGS)
Python
import pickle import base64 from django.contrib import admin from django.contrib.auth.models import User from django.db import models from oauth2client.django_orm import FlowField from oauth2client.django_orm import CredentialsField # The Flow could also be stored in memcache since it is short lived. class FlowModel(models.Model): id = models.ForeignKey(User, primary_key=True) flow = FlowField() class CredentialsModel(models.Model): id = models.ForeignKey(User, primary_key=True) credential = CredentialsField() class CredentialsAdmin(admin.ModelAdmin): pass class FlowAdmin(admin.ModelAdmin): pass admin.site.register(CredentialsModel, CredentialsAdmin) admin.site.register(FlowModel, FlowAdmin)
Python
""" This file demonstrates two different styles of tests (one doctest and one unittest). These will both pass when you run "manage.py test". Replace these with more appropriate tests for your application. """ from django.test import TestCase class SimpleTest(TestCase): def test_basic_addition(self): """ Tests that 1 + 1 always equals 2. """ self.failUnlessEqual(1 + 1, 2) __test__ = {"doctest": """ Another way to test that 1 + 1 is equal to 2. >>> 1 + 1 == 2 True """}
Python
import os import logging import httplib2 from django.http import HttpResponse from django.core.urlresolvers import reverse from django.contrib.auth.decorators import login_required from oauth2client.django_orm import Storage from oauth2client.client import OAuth2WebServerFlow from django_sample.buzz.models import CredentialsModel from django_sample.buzz.models import FlowModel from apiclient.discovery import build from django.http import HttpResponseRedirect from django.shortcuts import render_to_response STEP2_URI = 'http://localhost:8000/auth_return' @login_required def index(request): storage = Storage(CredentialsModel, 'id', request.user, 'credential') credential = storage.get() if credential is None or credential.invalid == True: flow = OAuth2WebServerFlow( client_id='837647042410.apps.googleusercontent.com', client_secret='+SWwMCL9d8gWtzPRa1lXw5R8', scope='https://www.googleapis.com/auth/buzz', user_agent='buzz-django-sample/1.0', ) authorize_url = flow.step1_get_authorize_url(STEP2_URI) f = FlowModel(id=request.user, flow=flow) f.save() return HttpResponseRedirect(authorize_url) else: http = httplib2.Http() http = credential.authorize(http) service = build("buzz", "v1", http=http) activities = service.activities() activitylist = activities.list(scope='@consumption', userId='@me').execute() logging.info(activitylist) return render_to_response('buzz/welcome.html', { 'activitylist': activitylist, }) @login_required def auth_return(request): try: f = FlowModel.objects.get(id=request.user) credential = f.flow.step2_exchange(request.REQUEST) storage = Storage(CredentialsModel, 'id', request.user, 'credential') storage.put(credential) f.delete() return HttpResponseRedirect("/") except FlowModel.DoesNotExist: pass
Python
#!/usr/bin/python from django.core.management import execute_manager try: import settings # Assumed to be in the same directory. except ImportError: import sys sys.stderr.write("""Error: Can't find the file 'settings.py' in the directory containing %r. It appears you've customized things. You'll have to run django-admin.py, passing it your settings module. (If the file settings.py does indeed exist, it's causing an ImportError somehow.)\n""" % __file__) sys.exit(1) if __name__ == "__main__": execute_manager(settings)
Python
#!/usr/bin/python from django.core.management import execute_manager try: import settings # Assumed to be in the same directory. except ImportError: import sys sys.stderr.write("""Error: Can't find the file 'settings.py' in the directory containing %r. It appears you've customized things. You'll have to run django-admin.py, passing it your settings module. (If the file settings.py does indeed exist, it's causing an ImportError somehow.)\n""" % __file__) sys.exit(1) if __name__ == "__main__": execute_manager(settings)
Python
import os from django.conf.urls.defaults import * # Uncomment the next two lines to enable the admin: from django.contrib import admin admin.autodiscover() urlpatterns = patterns('', # Example: (r'^$', 'django_sample.buzz.views.index'), (r'^auth_return', 'django_sample.buzz.views.auth_return'), # Uncomment the admin/doc line below and add 'django.contrib.admindocs' # to INSTALLED_APPS to enable admin documentation: # (r'^admin/doc/', include('django.contrib.admindocs.urls')), # Uncomment the next line to enable the admin: (r'^admin/', include(admin.site.urls)), (r'^accounts/login/$', 'django.contrib.auth.views.login', {'template_name': 'buzz/login.html'}), (r'^static/(?P<path>.*)$', 'django.views.static.serve', {'document_root': os.path.join(os.path.dirname(__file__), 'static') }), )
Python
# Django settings for django_sample project. import os DEBUG = True TEMPLATE_DEBUG = DEBUG ADMINS = ( # ('Your Name', 'your_email@domain.com'), ) MANAGERS = ADMINS DATABASE_ENGINE = 'sqlite3' DATABASE_NAME = 'database.sqlite3' DATABASE_USER = '' DATABASE_PASSWORD = '' DATABASE_HOST = '' DATABASE_PORT = '' # Local time zone for this installation. Choices can be found here: # http://en.wikipedia.org/wiki/List_of_tz_zones_by_name # although not all choices may be available on all operating systems. # If running in a Windows environment this must be set to the same as your # system time zone. TIME_ZONE = 'America/New_York' # Language code for this installation. All choices can be found here: # http://www.i18nguy.com/unicode/language-identifiers.html LANGUAGE_CODE = 'en-us' SITE_ID = 1 # If you set this to False, Django will make some optimizations so as not # to load the internationalization machinery. USE_I18N = True # Absolute path to the directory that holds media. # Example: "/home/media/media.lawrence.com/" MEDIA_ROOT = '' # URL that handles the media served from MEDIA_ROOT. Make sure to use a # trailing slash if there is a path component (optional in other cases). # Examples: "http://media.lawrence.com", "http://example.com/media/" MEDIA_URL = '' # URL prefix for admin media -- CSS, JavaScript and images. Make sure to use a # trailing slash. # Examples: "http://foo.com/media/", "/media/". ADMIN_MEDIA_PREFIX = '/media/' # Make this unique, and don't share it with anybody. SECRET_KEY = '_=9hq-$t_uv1ckf&s!y2$9g$1dm*6p1cl%*!^mg=7gr)!zj32d' # List of callables that know how to import templates from various sources. TEMPLATE_LOADERS = ( 'django.template.loaders.filesystem.load_template_source', 'django.template.loaders.app_directories.load_template_source', # 'django.template.loaders.eggs.load_template_source', ) MIDDLEWARE_CLASSES = ( 'django.middleware.common.CommonMiddleware', 'django.contrib.sessions.middleware.SessionMiddleware', 'django.contrib.auth.middleware.AuthenticationMiddleware', ) ROOT_URLCONF = 'django_sample.urls' TEMPLATE_DIRS = ( # Put strings here, like "/home/html/django_templates" # Always use forward slashes, even on Windows. # Don't forget to use absolute paths, not relative paths. os.path.join(os.path.dirname(__file__), 'templates') ) INSTALLED_APPS = ( 'django.contrib.admin', 'django.contrib.auth', 'django.contrib.contenttypes', 'django.contrib.sessions', 'django.contrib.sites', 'django_sample.buzz' )
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Simple command-line example for Latitude. Command-line application that sets the users current location. """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' from apiclient.discovery import build import httplib2 import pickle from apiclient.discovery import build from apiclient.oauth import FlowThreeLegged from apiclient.ext.authtools import run from apiclient.ext.file import Storage # Uncomment to get detailed logging # httplib2.debuglevel = 4 def main(): storage = Storage('latitude.dat') credentials = storage.get() if credentials is None or credentials.invalid == True: auth_discovery = build("latitude", "v1").auth_discovery() flow = FlowThreeLegged(auth_discovery, # You MUST have a consumer key and secret tied to a # registered domain to use the latitude API. # # https://www.google.com/accounts/ManageDomains consumer_key='REGISTERED DOMAIN NAME', consumer_secret='KEY GIVEN DURING REGISTRATION', user_agent='google-api-client-python-latitude/1.0', domain='REGISTERED DOMAIN NAME', scope='https://www.googleapis.com/auth/latitude', xoauth_displayname='Google API Latitude Example', location='current', granularity='city' ) credentials = run(flow, storage) http = httplib2.Http() http = credentials.authorize(http) service = build("latitude", "v1", http=http) body = { "data": { "kind": "latitude#location", "latitude": 37.420352, "longitude": -122.083389, "accuracy": 130, "altitude": 35 } } print service.currentLocation().insert(body=body).execute() if __name__ == '__main__': main()
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Simple command-line example for Latitude. Command-line application that sets the users current location. """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' from apiclient.discovery import build import httplib2 import pickle from apiclient.discovery import build from apiclient.oauth import FlowThreeLegged from apiclient.ext.authtools import run from apiclient.ext.file import Storage # Uncomment to get detailed logging # httplib2.debuglevel = 4 def main(): storage = Storage('latitude.dat') credentials = storage.get() if credentials is None or credentials.invalid == True: auth_discovery = build("latitude", "v1").auth_discovery() flow = FlowThreeLegged(auth_discovery, # You MUST have a consumer key and secret tied to a # registered domain to use the latitude API. # # https://www.google.com/accounts/ManageDomains consumer_key='REGISTERED DOMAIN NAME', consumer_secret='KEY GIVEN DURING REGISTRATION', user_agent='google-api-client-python-latitude/1.0', domain='REGISTERED DOMAIN NAME', scope='https://www.googleapis.com/auth/latitude', xoauth_displayname='Google API Latitude Example', location='current', granularity='city' ) credentials = run(flow, storage) http = httplib2.Http() http = credentials.authorize(http) service = build("latitude", "v1", http=http) body = { "data": { "kind": "latitude#location", "latitude": 37.420352, "longitude": -122.083389, "accuracy": 130, "altitude": 35 } } print service.currentLocation().insert(body=body).execute() if __name__ == '__main__': main()
Python
#!/usr/bin/env python # # Copyright 2007 Google Inc. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. # __author__ = 'jcgregorio@google.com (Joe Gregorio)' import httplib2 import logging import os import pickle from apiclient.discovery import build from apiclient.ext.appengine import FlowThreeLeggedProperty from apiclient.ext.appengine import OAuthCredentialsProperty from apiclient.ext.appengine import StorageByKeyName from apiclient.oauth import FlowThreeLegged from google.appengine.api import memcache from google.appengine.api import users from google.appengine.ext import db from google.appengine.ext import webapp from google.appengine.ext.webapp import util from google.appengine.ext.webapp.util import login_required APP_ID = os.environ['APPLICATION_ID'] class Credentials(db.Model): credentials = OAuthCredentialsProperty() class MainHandler(webapp.RequestHandler): @login_required def get(self): user = users.get_current_user() storage = StorageByKeyName(Credentials, user.user_id(), 'credentials') http = httplib2.Http() credentials = storage.get() if credentials: http = credentials.authorize(http) service = build("buzz", "v1", http=http) if not credentials: return begin_oauth_flow(self, user, service) followers = service.people().list( userId='@me', groupId='@followers').execute() self.response.out.write('Hello, you have %s followers!' % followers['totalResults']) def begin_oauth_flow(request_handler, user, service): flow = FlowThreeLegged(service.auth_discovery(), consumer_key='anonymous', consumer_secret='anonymous', user_agent='%s/1.0' % APP_ID, domain='anonymous', scope='https://www.googleapis.com/auth/buzz', xoauth_displayname='App Name') callback = self.request.relative_url('/auth_return') authorize_url = flow.step1_get_authorize_url(callback) memcache.set(user.user_id(), pickle.dumps(flow)) request_handler.redirect(authorize_url) class OAuthHandler(webapp.RequestHandler): @login_required def get(self): user = users.get_current_user() storage = StorageByKeyName(Credentials, user.user_id(), 'credentials') flow = pickle.loads(memcache.get(user.user_id())) credentials = flow.step2_exchange(self.request.params) storage.put(credentials) self.redirect("/") def main(): application = webapp.WSGIApplication( [ ('/', MainHandler), ('/auth_return', OAuthHandler) ], debug=True) util.run_wsgi_app(application) if __name__ == '__main__': main()
Python
#!/usr/bin/env python # Copyright (c) 2010, Google Inc. # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. """Module to enforce different constraints on flags. A validator represents an invariant, enforced over a one or more flags. See 'FLAGS VALIDATORS' in flags.py's docstring for a usage manual. """ __author__ = 'olexiy@google.com (Olexiy Oryeshko)' class Error(Exception): """Thrown If validator constraint is not satisfied.""" class Validator(object): """Base class for flags validators. Users should NOT overload these classes, and use flags.Register... methods instead. """ # Used to assign each validator an unique insertion_index validators_count = 0 def __init__(self, checker, message): """Constructor to create all validators. Args: checker: function to verify the constraint. Input of this method varies, see SimpleValidator and DictionaryValidator for a detailed description. message: string, error message to be shown to the user """ self.checker = checker self.message = message Validator.validators_count += 1 # Used to assert validators in the order they were registered (CL/18694236) self.insertion_index = Validator.validators_count def Verify(self, flag_values): """Verify that constraint is satisfied. flags library calls this method to verify Validator's constraint. Args: flag_values: flags.FlagValues, containing all flags Raises: Error: if constraint is not satisfied. """ param = self._GetInputToCheckerFunction(flag_values) if not self.checker(param): raise Error(self.message) def GetFlagsNames(self): """Return the names of the flags checked by this validator. Returns: [string], names of the flags """ raise NotImplementedError('This method should be overloaded') def PrintFlagsWithValues(self, flag_values): raise NotImplementedError('This method should be overloaded') def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues, containing all flags. Returns: Return type depends on the specific validator. """ raise NotImplementedError('This method should be overloaded') class SimpleValidator(Validator): """Validator behind RegisterValidator() method. Validates that a single flag passes its checker function. The checker function takes the flag value and returns True (if value looks fine) or, if flag value is not valid, either returns False or raises an Exception.""" def __init__(self, flag_name, checker, message): """Constructor. Args: flag_name: string, name of the flag. checker: function to verify the validator. input - value of the corresponding flag (string, boolean, etc). output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise Error. message: string, error message to be shown to the user if validator's condition is not satisfied """ super(SimpleValidator, self).__init__(checker, message) self.flag_name = flag_name def GetFlagsNames(self): return [self.flag_name] def PrintFlagsWithValues(self, flag_values): return 'flag --%s=%s' % (self.flag_name, flag_values[self.flag_name].value) def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues Returns: value of the corresponding flag. """ return flag_values[self.flag_name].value class DictionaryValidator(Validator): """Validator behind RegisterDictionaryValidator method. Validates that flag values pass their common checker function. The checker function takes flag values and returns True (if values look fine) or, if values are not valid, either returns False or raises an Exception. """ def __init__(self, flag_names, checker, message): """Constructor. Args: flag_names: [string], containing names of the flags used by checker. checker: function to verify the validator. input - dictionary, with keys() being flag_names, and value for each key being the value of the corresponding flag (string, boolean, etc). output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise Error. message: string, error message to be shown to the user if validator's condition is not satisfied """ super(DictionaryValidator, self).__init__(checker, message) self.flag_names = flag_names def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues Returns: dictionary, with keys() being self.lag_names, and value for each key being the value of the corresponding flag (string, boolean, etc). """ return dict([key, flag_values[key].value] for key in self.flag_names) def PrintFlagsWithValues(self, flag_values): prefix = 'flags ' flags_with_values = [] for key in self.flag_names: flags_with_values.append('%s=%s' % (key, flag_values[key].value)) return prefix + ', '.join(flags_with_values) def GetFlagsNames(self): return self.flag_names
Python
#!/usr/bin/env python # # Copyright 2007 Google Inc. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. # __author__ = 'jcgregorio@google.com (Joe Gregorio)' import httplib2 import logging import os import pickle from apiclient.discovery import build from apiclient.ext.appengine import FlowThreeLeggedProperty from apiclient.ext.appengine import OAuthCredentialsProperty from apiclient.ext.appengine import StorageByKeyName from apiclient.oauth import FlowThreeLegged from google.appengine.api import memcache from google.appengine.api import users from google.appengine.ext import db from google.appengine.ext import webapp from google.appengine.ext.webapp import util from google.appengine.ext.webapp.util import login_required APP_ID = os.environ['APPLICATION_ID'] class Credentials(db.Model): credentials = OAuthCredentialsProperty() class MainHandler(webapp.RequestHandler): @login_required def get(self): user = users.get_current_user() storage = StorageByKeyName(Credentials, user.user_id(), 'credentials') http = httplib2.Http() credentials = storage.get() if credentials: http = credentials.authorize(http) service = build("buzz", "v1", http=http) if not credentials: return begin_oauth_flow(self, user, service) followers = service.people().list( userId='@me', groupId='@followers').execute() self.response.out.write('Hello, you have %s followers!' % followers['totalResults']) def begin_oauth_flow(request_handler, user, service): flow = FlowThreeLegged(service.auth_discovery(), consumer_key='anonymous', consumer_secret='anonymous', user_agent='%s/1.0' % APP_ID, domain='anonymous', scope='https://www.googleapis.com/auth/buzz', xoauth_displayname='App Name') callback = self.request.relative_url('/auth_return') authorize_url = flow.step1_get_authorize_url(callback) memcache.set(user.user_id(), pickle.dumps(flow)) request_handler.redirect(authorize_url) class OAuthHandler(webapp.RequestHandler): @login_required def get(self): user = users.get_current_user() storage = StorageByKeyName(Credentials, user.user_id(), 'credentials') flow = pickle.loads(memcache.get(user.user_id())) credentials = flow.step2_exchange(self.request.params) storage.put(credentials) self.redirect("/") def main(): application = webapp.WSGIApplication( [ ('/', MainHandler), ('/auth_return', OAuthHandler) ], debug=True) util.run_wsgi_app(application) if __name__ == '__main__': main()
Python
#!/usr/bin/env python # Copyright (c) 2007, Google Inc. # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. # # --- # Author: Chad Lester # Design and style contributions by: # Amit Patel, Bogdan Cocosel, Daniel Dulitz, Eric Tiedemann, # Eric Veach, Laurence Gonsalves, Matthew Springer # Code reorganized a bit by Craig Silverstein """This module is used to define and parse command line flags. This module defines a *distributed* flag-definition policy: rather than an application having to define all flags in or near main(), each python module defines flags that are useful to it. When one python module imports another, it gains access to the other's flags. (This is implemented by having all modules share a common, global registry object containing all the flag information.) Flags are defined through the use of one of the DEFINE_xxx functions. The specific function used determines how the flag is parsed, checked, and optionally type-converted, when it's seen on the command line. IMPLEMENTATION: DEFINE_* creates a 'Flag' object and registers it with a 'FlagValues' object (typically the global FlagValues FLAGS, defined here). The 'FlagValues' object can scan the command line arguments and pass flag arguments to the corresponding 'Flag' objects for value-checking and type conversion. The converted flag values are available as attributes of the 'FlagValues' object. Code can access the flag through a FlagValues object, for instance gflags.FLAGS.myflag. Typically, the __main__ module passes the command line arguments to gflags.FLAGS for parsing. At bottom, this module calls getopt(), so getopt functionality is supported, including short- and long-style flags, and the use of -- to terminate flags. Methods defined by the flag module will throw 'FlagsError' exceptions. The exception argument will be a human-readable string. FLAG TYPES: This is a list of the DEFINE_*'s that you can do. All flags take a name, default value, help-string, and optional 'short' name (one-letter name). Some flags have other arguments, which are described with the flag. DEFINE_string: takes any input, and interprets it as a string. DEFINE_bool or DEFINE_boolean: typically does not take an argument: say --myflag to set FLAGS.myflag to true, or --nomyflag to set FLAGS.myflag to false. Alternately, you can say --myflag=true or --myflag=t or --myflag=1 or --myflag=false or --myflag=f or --myflag=0 DEFINE_float: takes an input and interprets it as a floating point number. Takes optional args lower_bound and upper_bound; if the number specified on the command line is out of range, it will raise a FlagError. DEFINE_integer: takes an input and interprets it as an integer. Takes optional args lower_bound and upper_bound as for floats. DEFINE_enum: takes a list of strings which represents legal values. If the command-line value is not in this list, raise a flag error. Otherwise, assign to FLAGS.flag as a string. DEFINE_list: Takes a comma-separated list of strings on the commandline. Stores them in a python list object. DEFINE_spaceseplist: Takes a space-separated list of strings on the commandline. Stores them in a python list object. Example: --myspacesepflag "foo bar baz" DEFINE_multistring: The same as DEFINE_string, except the flag can be specified more than once on the commandline. The result is a python list object (list of strings), even if the flag is only on the command line once. DEFINE_multi_int: The same as DEFINE_integer, except the flag can be specified more than once on the commandline. The result is a python list object (list of ints), even if the flag is only on the command line once. SPECIAL FLAGS: There are a few flags that have special meaning: --help prints a list of all the flags in a human-readable fashion --helpshort prints a list of all key flags (see below). --helpxml prints a list of all flags, in XML format. DO NOT parse the output of --help and --helpshort. Instead, parse the output of --helpxml. For more info, see "OUTPUT FOR --helpxml" below. --flagfile=foo read flags from file foo. --undefok=f1,f2 ignore unrecognized option errors for f1,f2. For boolean flags, you should use --undefok=boolflag, and --boolflag and --noboolflag will be accepted. Do not use --undefok=noboolflag. -- as in getopt(), terminates flag-processing FLAGS VALIDATORS: If your program: - requires flag X to be specified - needs flag Y to match a regular expression - or requires any more general constraint to be satisfied then validators are for you! Each validator represents a constraint over one flag, which is enforced starting from the initial parsing of the flags and until the program terminates. Also, lower_bound and upper_bound for numerical flags are enforced using flag validators. Howto: If you want to enforce a constraint over one flag, use flags.RegisterValidator(flag_name, checker, message='Flag validation failed', flag_values=FLAGS) After flag values are initially parsed, and after any change to the specified flag, method checker(flag_value) will be executed. If constraint is not satisfied, an IllegalFlagValue exception will be raised. See RegisterValidator's docstring for a detailed explanation on how to construct your own checker. EXAMPLE USAGE: FLAGS = flags.FLAGS flags.DEFINE_integer('my_version', 0, 'Version number.') flags.DEFINE_string('filename', None, 'Input file name', short_name='f') flags.RegisterValidator('my_version', lambda value: value % 2 == 0, message='--my_version must be divisible by 2') flags.MarkFlagAsRequired('filename') NOTE ON --flagfile: Flags may be loaded from text files in addition to being specified on the commandline. Any flags you don't feel like typing, throw them in a file, one flag per line, for instance: --myflag=myvalue --nomyboolean_flag You then specify your file with the special flag '--flagfile=somefile'. You CAN recursively nest flagfile= tokens OR use multiple files on the command line. Lines beginning with a single hash '#' or a double slash '//' are comments in your flagfile. Any flagfile=<file> will be interpreted as having a relative path from the current working directory rather than from the place the file was included from: myPythonScript.py --flagfile=config/somefile.cfg If somefile.cfg includes further --flagfile= directives, these will be referenced relative to the original CWD, not from the directory the including flagfile was found in! The caveat applies to people who are including a series of nested files in a different dir than they are executing out of. Relative path names are always from CWD, not from the directory of the parent include flagfile. We do now support '~' expanded directory names. Absolute path names ALWAYS work! EXAMPLE USAGE: import gflags FLAGS = gflags.FLAGS # Flag names are globally defined! So in general, we need to be # careful to pick names that are unlikely to be used by other libraries. # If there is a conflict, we'll get an error at import time. gflags.DEFINE_string('name', 'Mr. President', 'your name') gflags.DEFINE_integer('age', None, 'your age in years', lower_bound=0) gflags.DEFINE_boolean('debug', False, 'produces debugging output') gflags.DEFINE_enum('gender', 'male', ['male', 'female'], 'your gender') def main(argv): try: argv = FLAGS(argv) # parse flags except gflags.FlagsError, e: print '%s\\nUsage: %s ARGS\\n%s' % (e, sys.argv[0], FLAGS) sys.exit(1) if FLAGS.debug: print 'non-flag arguments:', argv print 'Happy Birthday', FLAGS.name if FLAGS.age is not None: print 'You are a %s, who is %d years old' % (FLAGS.gender, FLAGS.age) if __name__ == '__main__': main(sys.argv) KEY FLAGS: As we already explained, each module gains access to all flags defined by all the other modules it transitively imports. In the case of non-trivial scripts, this means a lot of flags ... For documentation purposes, it is good to identify the flags that are key (i.e., really important) to a module. Clearly, the concept of "key flag" is a subjective one. When trying to determine whether a flag is key to a module or not, assume that you are trying to explain your module to a potential user: which flags would you really like to mention first? We'll describe shortly how to declare which flags are key to a module. For the moment, assume we know the set of key flags for each module. Then, if you use the app.py module, you can use the --helpshort flag to print only the help for the flags that are key to the main module, in a human-readable format. NOTE: If you need to parse the flag help, do NOT use the output of --help / --helpshort. That output is meant for human consumption, and may be changed in the future. Instead, use --helpxml; flags that are key for the main module are marked there with a <key>yes</key> element. The set of key flags for a module M is composed of: 1. Flags defined by module M by calling a DEFINE_* function. 2. Flags that module M explictly declares as key by using the function DECLARE_key_flag(<flag_name>) 3. Key flags of other modules that M specifies by using the function ADOPT_module_key_flags(<other_module>) This is a "bulk" declaration of key flags: each flag that is key for <other_module> becomes key for the current module too. Notice that if you do not use the functions described at points 2 and 3 above, then --helpshort prints information only about the flags defined by the main module of our script. In many cases, this behavior is good enough. But if you move part of the main module code (together with the related flags) into a different module, then it is nice to use DECLARE_key_flag / ADOPT_module_key_flags and make sure --helpshort lists all relevant flags (otherwise, your code refactoring may confuse your users). Note: each of DECLARE_key_flag / ADOPT_module_key_flags has its own pluses and minuses: DECLARE_key_flag is more targeted and may lead a more focused --helpshort documentation. ADOPT_module_key_flags is good for cases when an entire module is considered key to the current script. Also, it does not require updates to client scripts when a new flag is added to the module. EXAMPLE USAGE 2 (WITH KEY FLAGS): Consider an application that contains the following three files (two auxiliary modules and a main module): File libfoo.py: import gflags gflags.DEFINE_integer('num_replicas', 3, 'Number of replicas to start') gflags.DEFINE_boolean('rpc2', True, 'Turn on the usage of RPC2.') ... some code ... File libbar.py: import gflags gflags.DEFINE_string('bar_gfs_path', '/gfs/path', 'Path to the GFS files for libbar.') gflags.DEFINE_string('email_for_bar_errors', 'bar-team@google.com', 'Email address for bug reports about module libbar.') gflags.DEFINE_boolean('bar_risky_hack', False, 'Turn on an experimental and buggy optimization.') ... some code ... File myscript.py: import gflags import libfoo import libbar gflags.DEFINE_integer('num_iterations', 0, 'Number of iterations.') # Declare that all flags that are key for libfoo are # key for this module too. gflags.ADOPT_module_key_flags(libfoo) # Declare that the flag --bar_gfs_path (defined in libbar) is key # for this module. gflags.DECLARE_key_flag('bar_gfs_path') ... some code ... When myscript is invoked with the flag --helpshort, the resulted help message lists information about all the key flags for myscript: --num_iterations, --num_replicas, --rpc2, and --bar_gfs_path (in addition to the special flags --help and --helpshort). Of course, myscript uses all the flags declared by it (in this case, just --num_replicas) or by any of the modules it transitively imports (e.g., the modules libfoo, libbar). E.g., it can access the value of FLAGS.bar_risky_hack, even if --bar_risky_hack is not declared as a key flag for myscript. OUTPUT FOR --helpxml: The --helpxml flag generates output with the following structure: <?xml version="1.0"?> <AllFlags> <program>PROGRAM_BASENAME</program> <usage>MAIN_MODULE_DOCSTRING</usage> (<flag> [<key>yes</key>] <file>DECLARING_MODULE</file> <name>FLAG_NAME</name> <meaning>FLAG_HELP_MESSAGE</meaning> <default>DEFAULT_FLAG_VALUE</default> <current>CURRENT_FLAG_VALUE</current> <type>FLAG_TYPE</type> [OPTIONAL_ELEMENTS] </flag>)* </AllFlags> Notes: 1. The output is intentionally similar to the output generated by the C++ command-line flag library. The few differences are due to the Python flags that do not have a C++ equivalent (at least not yet), e.g., DEFINE_list. 2. New XML elements may be added in the future. 3. DEFAULT_FLAG_VALUE is in serialized form, i.e., the string you can pass for this flag on the command-line. E.g., for a flag defined using DEFINE_list, this field may be foo,bar, not ['foo', 'bar']. 4. CURRENT_FLAG_VALUE is produced using str(). This means that the string 'false' will be represented in the same way as the boolean False. Using repr() would have removed this ambiguity and simplified parsing, but would have broken the compatibility with the C++ command-line flags. 5. OPTIONAL_ELEMENTS describe elements relevant for certain kinds of flags: lower_bound, upper_bound (for flags that specify bounds), enum_value (for enum flags), list_separator (for flags that consist of a list of values, separated by a special token). 6. We do not provide any example here: please use --helpxml instead. """ import cgi import getopt import os import re import string import sys import gflags_validators # Are we running at least python 2.2? try: if tuple(sys.version_info[:3]) < (2,2,0): raise NotImplementedError("requires python 2.2.0 or later") except AttributeError: # a very old python, that lacks sys.version_info raise NotImplementedError("requires python 2.2.0 or later") # If we're not running at least python 2.2.1, define True, False, and bool. # Thanks, Guido, for the code. try: True, False, bool except NameError: False = 0 True = 1 def bool(x): if x: return True else: return False # Are we running under pychecker? _RUNNING_PYCHECKER = 'pychecker.python' in sys.modules def _GetCallingModule(): """Returns the name of the module that's calling into this module. We generally use this function to get the name of the module calling a DEFINE_foo... function. """ # Walk down the stack to find the first globals dict that's not ours. for depth in range(1, sys.getrecursionlimit()): if not sys._getframe(depth).f_globals is globals(): globals_for_frame = sys._getframe(depth).f_globals module_name = _GetModuleObjectAndName(globals_for_frame)[1] if module_name is not None: return module_name raise AssertionError("No module was found") def _GetThisModuleObjectAndName(): """Returns: (module object, module name) for this module.""" return _GetModuleObjectAndName(globals()) # module exceptions: class FlagsError(Exception): """The base class for all flags errors.""" pass class DuplicateFlag(FlagsError): """Raised if there is a flag naming conflict.""" pass class DuplicateFlagCannotPropagateNoneToSwig(DuplicateFlag): """Special case of DuplicateFlag -- SWIG flag value can't be set to None. This can be raised when a duplicate flag is created. Even if allow_override is True, we still abort if the new value is None, because it's currently impossible to pass None default value back to SWIG. See FlagValues.SetDefault for details. """ pass # A DuplicateFlagError conveys more information than a # DuplicateFlag. Since there are external modules that create # DuplicateFlags, the interface to DuplicateFlag shouldn't change. class DuplicateFlagError(DuplicateFlag): def __init__(self, flagname, flag_values): self.flagname = flagname message = "The flag '%s' is defined twice." % self.flagname flags_by_module = flag_values.FlagsByModuleDict() for module in flags_by_module: for flag in flags_by_module[module]: if flag.name == flagname or flag.short_name == flagname: message = message + " First from " + module + "," break message = message + " Second from " + _GetCallingModule() DuplicateFlag.__init__(self, message) class IllegalFlagValue(FlagsError): """The flag command line argument is illegal.""" pass class UnrecognizedFlag(FlagsError): """Raised if a flag is unrecognized.""" pass # An UnrecognizedFlagError conveys more information than an UnrecognizedFlag. # Since there are external modules that create DuplicateFlags, the interface to # DuplicateFlag shouldn't change. The flagvalue will be assigned the full value # of the flag and its argument, if any, allowing handling of unrecognzed flags # in an exception handler. # If flagvalue is the empty string, then this exception is an due to a # reference to a flag that was not already defined. class UnrecognizedFlagError(UnrecognizedFlag): def __init__(self, flagname, flagvalue=''): self.flagname = flagname self.flagvalue = flagvalue UnrecognizedFlag.__init__( self, "Unknown command line flag '%s'" % flagname) # Global variable used by expvar _exported_flags = {} _help_width = 80 # width of help output def GetHelpWidth(): """Returns: an integer, the width of help lines that is used in TextWrap.""" return _help_width def CutCommonSpacePrefix(text): """Removes a common space prefix from the lines of a multiline text. If the first line does not start with a space, it is left as it is and only in the remaining lines a common space prefix is being searched for. That means the first line will stay untouched. This is especially useful to turn doc strings into help texts. This is because some people prefer to have the doc comment start already after the apostrophy and then align the following lines while others have the apostrophies on a seperately line. The function also drops trailing empty lines and ignores empty lines following the initial content line while calculating the initial common whitespace. Args: text: text to work on Returns: the resulting text """ text_lines = text.splitlines() # Drop trailing empty lines while text_lines and not text_lines[-1]: text_lines = text_lines[:-1] if text_lines: # We got some content, is the first line starting with a space? if text_lines[0] and text_lines[0][0].isspace(): text_first_line = [] else: text_first_line = [text_lines.pop(0)] # Calculate length of common leading whitesppace (only over content lines) common_prefix = os.path.commonprefix([line for line in text_lines if line]) space_prefix_len = len(common_prefix) - len(common_prefix.lstrip()) # If we have a common space prefix, drop it from all lines if space_prefix_len: for index in xrange(len(text_lines)): if text_lines[index]: text_lines[index] = text_lines[index][space_prefix_len:] return '\n'.join(text_first_line + text_lines) return '' def TextWrap(text, length=None, indent='', firstline_indent=None, tabs=' '): """Wraps a given text to a maximum line length and returns it. We turn lines that only contain whitespaces into empty lines. We keep new lines and tabs (e.g., we do not treat tabs as spaces). Args: text: text to wrap length: maximum length of a line, includes indentation if this is None then use GetHelpWidth() indent: indent for all but first line firstline_indent: indent for first line; if None, fall back to indent tabs: replacement for tabs Returns: wrapped text Raises: FlagsError: if indent not shorter than length FlagsError: if firstline_indent not shorter than length """ # Get defaults where callee used None if length is None: length = GetHelpWidth() if indent is None: indent = '' if len(indent) >= length: raise FlagsError('Indent must be shorter than length') # In line we will be holding the current line which is to be started # with indent (or firstline_indent if available) and then appended # with words. if firstline_indent is None: firstline_indent = '' line = indent else: line = firstline_indent if len(firstline_indent) >= length: raise FlagsError('First iline indent must be shorter than length') # If the callee does not care about tabs we simply convert them to # spaces If callee wanted tabs to be single space then we do that # already here. if not tabs or tabs == ' ': text = text.replace('\t', ' ') else: tabs_are_whitespace = not tabs.strip() line_regex = re.compile('([ ]*)(\t*)([^ \t]+)', re.MULTILINE) # Split the text into lines and the lines with the regex above. The # resulting lines are collected in result[]. For each split we get the # spaces, the tabs and the next non white space (e.g. next word). result = [] for text_line in text.splitlines(): # Store result length so we can find out whether processing the next # line gave any new content old_result_len = len(result) # Process next line with line_regex. For optimization we do an rstrip(). # - process tabs (changes either line or word, see below) # - process word (first try to squeeze on line, then wrap or force wrap) # Spaces found on the line are ignored, they get added while wrapping as # needed. for spaces, current_tabs, word in line_regex.findall(text_line.rstrip()): # If tabs weren't converted to spaces, handle them now if current_tabs: # If the last thing we added was a space anyway then drop # it. But let's not get rid of the indentation. if (((result and line != indent) or (not result and line != firstline_indent)) and line[-1] == ' '): line = line[:-1] # Add the tabs, if that means adding whitespace, just add it at # the line, the rstrip() code while shorten the line down if # necessary if tabs_are_whitespace: line += tabs * len(current_tabs) else: # if not all tab replacement is whitespace we prepend it to the word word = tabs * len(current_tabs) + word # Handle the case where word cannot be squeezed onto current last line if len(line) + len(word) > length and len(indent) + len(word) <= length: result.append(line.rstrip()) line = indent + word word = '' # No space left on line or can we append a space? if len(line) + 1 >= length: result.append(line.rstrip()) line = indent else: line += ' ' # Add word and shorten it up to allowed line length. Restart next # line with indent and repeat, or add a space if we're done (word # finished) This deals with words that caanot fit on one line # (e.g. indent + word longer than allowed line length). while len(line) + len(word) >= length: line += word result.append(line[:length]) word = line[length:] line = indent # Default case, simply append the word and a space if word: line += word + ' ' # End of input line. If we have content we finish the line. If the # current line is just the indent but we had content in during this # original line then we need to add an emoty line. if (result and line != indent) or (not result and line != firstline_indent): result.append(line.rstrip()) elif len(result) == old_result_len: result.append('') line = indent return '\n'.join(result) def DocToHelp(doc): """Takes a __doc__ string and reformats it as help.""" # Get rid of starting and ending white space. Using lstrip() or even # strip() could drop more than maximum of first line and right space # of last line. doc = doc.strip() # Get rid of all empty lines whitespace_only_line = re.compile('^[ \t]+$', re.M) doc = whitespace_only_line.sub('', doc) # Cut out common space at line beginnings doc = CutCommonSpacePrefix(doc) # Just like this module's comment, comments tend to be aligned somehow. # In other words they all start with the same amount of white space # 1) keep double new lines # 2) keep ws after new lines if not empty line # 3) all other new lines shall be changed to a space # Solution: Match new lines between non white space and replace with space. doc = re.sub('(?<=\S)\n(?=\S)', ' ', doc, re.M) return doc def _GetModuleObjectAndName(globals_dict): """Returns the module that defines a global environment, and its name. Args: globals_dict: A dictionary that should correspond to an environment providing the values of the globals. Returns: A pair consisting of (1) module object and (2) module name (a string). Returns (None, None) if the module could not be identified. """ # The use of .items() (instead of .iteritems()) is NOT a mistake: if # a parallel thread imports a module while we iterate over # .iteritems() (not nice, but possible), we get a RuntimeError ... # Hence, we use the slightly slower but safer .items(). for name, module in sys.modules.items(): if getattr(module, '__dict__', None) is globals_dict: if name == '__main__': # Pick a more informative name for the main module. name = sys.argv[0] return (module, name) return (None, None) def _GetMainModule(): """Returns the name of the module from which execution started.""" for depth in range(1, sys.getrecursionlimit()): try: globals_of_main = sys._getframe(depth).f_globals except ValueError: return _GetModuleObjectAndName(globals_of_main)[1] raise AssertionError("No module was found") class FlagValues: """Registry of 'Flag' objects. A 'FlagValues' can then scan command line arguments, passing flag arguments through to the 'Flag' objects that it owns. It also provides easy access to the flag values. Typically only one 'FlagValues' object is needed by an application: gflags.FLAGS This class is heavily overloaded: 'Flag' objects are registered via __setitem__: FLAGS['longname'] = x # register a new flag The .value attribute of the registered 'Flag' objects can be accessed as attributes of this 'FlagValues' object, through __getattr__. Both the long and short name of the original 'Flag' objects can be used to access its value: FLAGS.longname # parsed flag value FLAGS.x # parsed flag value (short name) Command line arguments are scanned and passed to the registered 'Flag' objects through the __call__ method. Unparsed arguments, including argv[0] (e.g. the program name) are returned. argv = FLAGS(sys.argv) # scan command line arguments The original registered Flag objects can be retrieved through the use of the dictionary-like operator, __getitem__: x = FLAGS['longname'] # access the registered Flag object The str() operator of a 'FlagValues' object provides help for all of the registered 'Flag' objects. """ def __init__(self): # Since everything in this class is so heavily overloaded, the only # way of defining and using fields is to access __dict__ directly. # Dictionary: flag name (string) -> Flag object. self.__dict__['__flags'] = {} # Dictionary: module name (string) -> list of Flag objects that are defined # by that module. self.__dict__['__flags_by_module'] = {} # Dictionary: module name (string) -> list of Flag objects that are # key for that module. self.__dict__['__key_flags_by_module'] = {} # Set if we should use new style gnu_getopt rather than getopt when parsing # the args. Only possible with Python 2.3+ self.UseGnuGetOpt(False) def UseGnuGetOpt(self, use_gnu_getopt=True): self.__dict__['__use_gnu_getopt'] = use_gnu_getopt def IsGnuGetOpt(self): return self.__dict__['__use_gnu_getopt'] def FlagDict(self): return self.__dict__['__flags'] def FlagsByModuleDict(self): """Returns the dictionary of module_name -> list of defined flags. Returns: A dictionary. Its keys are module names (strings). Its values are lists of Flag objects. """ return self.__dict__['__flags_by_module'] def KeyFlagsByModuleDict(self): """Returns the dictionary of module_name -> list of key flags. Returns: A dictionary. Its keys are module names (strings). Its values are lists of Flag objects. """ return self.__dict__['__key_flags_by_module'] def _RegisterFlagByModule(self, module_name, flag): """Records the module that defines a specific flag. We keep track of which flag is defined by which module so that we can later sort the flags by module. Args: module_name: A string, the name of a Python module. flag: A Flag object, a flag that is key to the module. """ flags_by_module = self.FlagsByModuleDict() flags_by_module.setdefault(module_name, []).append(flag) def _RegisterKeyFlagForModule(self, module_name, flag): """Specifies that a flag is a key flag for a module. Args: module_name: A string, the name of a Python module. flag: A Flag object, a flag that is key to the module. """ key_flags_by_module = self.KeyFlagsByModuleDict() # The list of key flags for the module named module_name. key_flags = key_flags_by_module.setdefault(module_name, []) # Add flag, but avoid duplicates. if flag not in key_flags: key_flags.append(flag) def _GetFlagsDefinedByModule(self, module): """Returns the list of flags defined by a module. Args: module: A module object or a module name (a string). Returns: A new list of Flag objects. Caller may update this list as he wishes: none of those changes will affect the internals of this FlagValue object. """ if not isinstance(module, str): module = module.__name__ return list(self.FlagsByModuleDict().get(module, [])) def _GetKeyFlagsForModule(self, module): """Returns the list of key flags for a module. Args: module: A module object or a module name (a string) Returns: A new list of Flag objects. Caller may update this list as he wishes: none of those changes will affect the internals of this FlagValue object. """ if not isinstance(module, str): module = module.__name__ # Any flag is a key flag for the module that defined it. NOTE: # key_flags is a fresh list: we can update it without affecting the # internals of this FlagValues object. key_flags = self._GetFlagsDefinedByModule(module) # Take into account flags explicitly declared as key for a module. for flag in self.KeyFlagsByModuleDict().get(module, []): if flag not in key_flags: key_flags.append(flag) return key_flags def AppendFlagValues(self, flag_values): """Appends flags registered in another FlagValues instance. Args: flag_values: registry to copy from """ for flag_name, flag in flag_values.FlagDict().iteritems(): # Each flags with shortname appears here twice (once under its # normal name, and again with its short name). To prevent # problems (DuplicateFlagError) with double flag registration, we # perform a check to make sure that the entry we're looking at is # for its normal name. if flag_name == flag.name: self[flag_name] = flag def RemoveFlagValues(self, flag_values): """Remove flags that were previously appended from another FlagValues. Args: flag_values: registry containing flags to remove. """ for flag_name in flag_values.FlagDict(): self.__delattr__(flag_name) def __setitem__(self, name, flag): """Registers a new flag variable.""" fl = self.FlagDict() if not isinstance(flag, Flag): raise IllegalFlagValue(flag) if not isinstance(name, type("")): raise FlagsError("Flag name must be a string") if len(name) == 0: raise FlagsError("Flag name cannot be empty") # If running under pychecker, duplicate keys are likely to be # defined. Disable check for duplicate keys when pycheck'ing. if (fl.has_key(name) and not flag.allow_override and not fl[name].allow_override and not _RUNNING_PYCHECKER): raise DuplicateFlagError(name, self) short_name = flag.short_name if short_name is not None: if (fl.has_key(short_name) and not flag.allow_override and not fl[short_name].allow_override and not _RUNNING_PYCHECKER): raise DuplicateFlagError(short_name, self) fl[short_name] = flag fl[name] = flag global _exported_flags _exported_flags[name] = flag def __getitem__(self, name): """Retrieves the Flag object for the flag --name.""" return self.FlagDict()[name] def __getattr__(self, name): """Retrieves the 'value' attribute of the flag --name.""" fl = self.FlagDict() if not fl.has_key(name): raise AttributeError(name) return fl[name].value def __setattr__(self, name, value): """Sets the 'value' attribute of the flag --name.""" fl = self.FlagDict() fl[name].value = value self._AssertValidators(fl[name].validators) return value def _AssertAllValidators(self): all_validators = set() for flag in self.FlagDict().itervalues(): for validator in flag.validators: all_validators.add(validator) self._AssertValidators(all_validators) def _AssertValidators(self, validators): """Assert if all validators in the list are satisfied. Asserts validators in the order they were created. Args: validators: Iterable(gflags_validators.Validator), validators to be verified Raises: AttributeError: if validators work with a non-existing flag. IllegalFlagValue: if validation fails for at least one validator """ for validator in sorted( validators, key=lambda validator: validator.insertion_index): try: validator.Verify(self) except gflags_validators.Error, e: message = validator.PrintFlagsWithValues(self) raise IllegalFlagValue('%s: %s' % (message, str(e))) def _FlagIsRegistered(self, flag_obj): """Checks whether a Flag object is registered under some name. Note: this is non trivial: in addition to its normal name, a flag may have a short name too. In self.FlagDict(), both the normal and the short name are mapped to the same flag object. E.g., calling only "del FLAGS.short_name" is not unregistering the corresponding Flag object (it is still registered under the longer name). Args: flag_obj: A Flag object. Returns: A boolean: True iff flag_obj is registered under some name. """ flag_dict = self.FlagDict() # Check whether flag_obj is registered under its long name. name = flag_obj.name if flag_dict.get(name, None) == flag_obj: return True # Check whether flag_obj is registered under its short name. short_name = flag_obj.short_name if (short_name is not None and flag_dict.get(short_name, None) == flag_obj): return True # The flag cannot be registered under any other name, so we do not # need to do a full search through the values of self.FlagDict(). return False def __delattr__(self, flag_name): """Deletes a previously-defined flag from a flag object. This method makes sure we can delete a flag by using del flag_values_object.<flag_name> E.g., flags.DEFINE_integer('foo', 1, 'Integer flag.') del flags.FLAGS.foo Args: flag_name: A string, the name of the flag to be deleted. Raises: AttributeError: When there is no registered flag named flag_name. """ fl = self.FlagDict() if flag_name not in fl: raise AttributeError(flag_name) flag_obj = fl[flag_name] del fl[flag_name] if not self._FlagIsRegistered(flag_obj): # If the Flag object indicated by flag_name is no longer # registered (please see the docstring of _FlagIsRegistered), then # we delete the occurences of the flag object in all our internal # dictionaries. self.__RemoveFlagFromDictByModule(self.FlagsByModuleDict(), flag_obj) self.__RemoveFlagFromDictByModule(self.KeyFlagsByModuleDict(), flag_obj) def __RemoveFlagFromDictByModule(self, flags_by_module_dict, flag_obj): """Removes a flag object from a module -> list of flags dictionary. Args: flags_by_module_dict: A dictionary that maps module names to lists of flags. flag_obj: A flag object. """ for unused_module, flags_in_module in flags_by_module_dict.iteritems(): # while (as opposed to if) takes care of multiple occurences of a # flag in the list for the same module. while flag_obj in flags_in_module: flags_in_module.remove(flag_obj) def SetDefault(self, name, value): """Changes the default value of the named flag object.""" fl = self.FlagDict() if not fl.has_key(name): raise AttributeError(name) fl[name].SetDefault(value) self._AssertValidators(fl[name].validators) def __contains__(self, name): """Returns True if name is a value (flag) in the dict.""" return name in self.FlagDict() has_key = __contains__ # a synonym for __contains__() def __iter__(self): return self.FlagDict().iterkeys() def __call__(self, argv): """Parses flags from argv; stores parsed flags into this FlagValues object. All unparsed arguments are returned. Flags are parsed using the GNU Program Argument Syntax Conventions, using getopt: http://www.gnu.org/software/libc/manual/html_mono/libc.html#Getopt Args: argv: argument list. Can be of any type that may be converted to a list. Returns: The list of arguments not parsed as options, including argv[0] Raises: FlagsError: on any parsing error """ # Support any sequence type that can be converted to a list argv = list(argv) shortopts = "" longopts = [] fl = self.FlagDict() # This pre parses the argv list for --flagfile=<> options. argv = argv[:1] + self.ReadFlagsFromFiles(argv[1:], force_gnu=False) # Correct the argv to support the google style of passing boolean # parameters. Boolean parameters may be passed by using --mybool, # --nomybool, --mybool=(true|false|1|0). getopt does not support # having options that may or may not have a parameter. We replace # instances of the short form --mybool and --nomybool with their # full forms: --mybool=(true|false). original_argv = list(argv) # list() makes a copy shortest_matches = None for name, flag in fl.items(): if not flag.boolean: continue if shortest_matches is None: # Determine the smallest allowable prefix for all flag names shortest_matches = self.ShortestUniquePrefixes(fl) no_name = 'no' + name prefix = shortest_matches[name] no_prefix = shortest_matches[no_name] # Replace all occurences of this boolean with extended forms for arg_idx in range(1, len(argv)): arg = argv[arg_idx] if arg.find('=') >= 0: continue if arg.startswith('--'+prefix) and ('--'+name).startswith(arg): argv[arg_idx] = ('--%s=true' % name) elif arg.startswith('--'+no_prefix) and ('--'+no_name).startswith(arg): argv[arg_idx] = ('--%s=false' % name) # Loop over all of the flags, building up the lists of short options # and long options that will be passed to getopt. Short options are # specified as a string of letters, each letter followed by a colon # if it takes an argument. Long options are stored in an array of # strings. Each string ends with an '=' if it takes an argument. for name, flag in fl.items(): longopts.append(name + "=") if len(name) == 1: # one-letter option: allow short flag type also shortopts += name if not flag.boolean: shortopts += ":" longopts.append('undefok=') undefok_flags = [] # In case --undefok is specified, loop to pick up unrecognized # options one by one. unrecognized_opts = [] args = argv[1:] while True: try: if self.__dict__['__use_gnu_getopt']: optlist, unparsed_args = getopt.gnu_getopt(args, shortopts, longopts) else: optlist, unparsed_args = getopt.getopt(args, shortopts, longopts) break except getopt.GetoptError, e: if not e.opt or e.opt in fl: # Not an unrecognized option, reraise the exception as a FlagsError raise FlagsError(e) # Remove offender from args and try again for arg_index in range(len(args)): if ((args[arg_index] == '--' + e.opt) or (args[arg_index] == '-' + e.opt) or (args[arg_index].startswith('--' + e.opt + '='))): unrecognized_opts.append((e.opt, args[arg_index])) args = args[0:arg_index] + args[arg_index+1:] break else: # We should have found the option, so we don't expect to get # here. We could assert, but raising the original exception # might work better. raise FlagsError(e) for name, arg in optlist: if name == '--undefok': flag_names = arg.split(',') undefok_flags.extend(flag_names) # For boolean flags, if --undefok=boolflag is specified, then we should # also accept --noboolflag, in addition to --boolflag. # Since we don't know the type of the undefok'd flag, this will affect # non-boolean flags as well. # NOTE: You shouldn't use --undefok=noboolflag, because then we will # accept --nonoboolflag here. We are choosing not to do the conversion # from noboolflag -> boolflag because of the ambiguity that flag names # can start with 'no'. undefok_flags.extend('no' + name for name in flag_names) continue if name.startswith('--'): # long option name = name[2:] short_option = 0 else: # short option name = name[1:] short_option = 1 if fl.has_key(name): flag = fl[name] if flag.boolean and short_option: arg = 1 flag.Parse(arg) # If there were unrecognized options, raise an exception unless # the options were named via --undefok. for opt, value in unrecognized_opts: if opt not in undefok_flags: raise UnrecognizedFlagError(opt, value) if unparsed_args: if self.__dict__['__use_gnu_getopt']: # if using gnu_getopt just return the program name + remainder of argv. ret_val = argv[:1] + unparsed_args else: # unparsed_args becomes the first non-flag detected by getopt to # the end of argv. Because argv may have been modified above, # return original_argv for this region. ret_val = argv[:1] + original_argv[-len(unparsed_args):] else: ret_val = argv[:1] self._AssertAllValidators() return ret_val def Reset(self): """Resets the values to the point before FLAGS(argv) was called.""" for f in self.FlagDict().values(): f.Unparse() def RegisteredFlags(self): """Returns: a list of the names and short names of all registered flags.""" return self.FlagDict().keys() def FlagValuesDict(self): """Returns: a dictionary that maps flag names to flag values.""" flag_values = {} for flag_name in self.RegisteredFlags(): flag = self.FlagDict()[flag_name] flag_values[flag_name] = flag.value return flag_values def __str__(self): """Generates a help string for all known flags.""" return self.GetHelp() def GetHelp(self, prefix=''): """Generates a help string for all known flags.""" helplist = [] flags_by_module = self.FlagsByModuleDict() if flags_by_module: modules = flags_by_module.keys() modules.sort() # Print the help for the main module first, if possible. main_module = _GetMainModule() if main_module in modules: modules.remove(main_module) modules = [main_module] + modules for module in modules: self.__RenderOurModuleFlags(module, helplist) self.__RenderModuleFlags('gflags', _SPECIAL_FLAGS.FlagDict().values(), helplist) else: # Just print one long list of flags. self.__RenderFlagList( self.FlagDict().values() + _SPECIAL_FLAGS.FlagDict().values(), helplist, prefix) return '\n'.join(helplist) def __RenderModuleFlags(self, module, flags, output_lines, prefix=""): """Generates a help string for a given module.""" if not isinstance(module, str): module = module.__name__ output_lines.append('\n%s%s:' % (prefix, module)) self.__RenderFlagList(flags, output_lines, prefix + " ") def __RenderOurModuleFlags(self, module, output_lines, prefix=""): """Generates a help string for a given module.""" flags = self._GetFlagsDefinedByModule(module) if flags: self.__RenderModuleFlags(module, flags, output_lines, prefix) def __RenderOurModuleKeyFlags(self, module, output_lines, prefix=""): """Generates a help string for the key flags of a given module. Args: module: A module object or a module name (a string). output_lines: A list of strings. The generated help message lines will be appended to this list. prefix: A string that is prepended to each generated help line. """ key_flags = self._GetKeyFlagsForModule(module) if key_flags: self.__RenderModuleFlags(module, key_flags, output_lines, prefix) def ModuleHelp(self, module): """Describe the key flags of a module. Args: module: A module object or a module name (a string). Returns: string describing the key flags of a module. """ helplist = [] self.__RenderOurModuleKeyFlags(module, helplist) return '\n'.join(helplist) def MainModuleHelp(self): """Describe the key flags of the main module. Returns: string describing the key flags of a module. """ return self.ModuleHelp(_GetMainModule()) def __RenderFlagList(self, flaglist, output_lines, prefix=" "): fl = self.FlagDict() special_fl = _SPECIAL_FLAGS.FlagDict() flaglist = [(flag.name, flag) for flag in flaglist] flaglist.sort() flagset = {} for (name, flag) in flaglist: # It's possible this flag got deleted or overridden since being # registered in the per-module flaglist. Check now against the # canonical source of current flag information, the FlagDict. if fl.get(name, None) != flag and special_fl.get(name, None) != flag: # a different flag is using this name now continue # only print help once if flagset.has_key(flag): continue flagset[flag] = 1 flaghelp = "" if flag.short_name: flaghelp += "-%s," % flag.short_name if flag.boolean: flaghelp += "--[no]%s" % flag.name + ":" else: flaghelp += "--%s" % flag.name + ":" flaghelp += " " if flag.help: flaghelp += flag.help flaghelp = TextWrap(flaghelp, indent=prefix+" ", firstline_indent=prefix) if flag.default_as_str: flaghelp += "\n" flaghelp += TextWrap("(default: %s)" % flag.default_as_str, indent=prefix+" ") if flag.parser.syntactic_help: flaghelp += "\n" flaghelp += TextWrap("(%s)" % flag.parser.syntactic_help, indent=prefix+" ") output_lines.append(flaghelp) def get(self, name, default): """Returns the value of a flag (if not None) or a default value. Args: name: A string, the name of a flag. default: Default value to use if the flag value is None. """ value = self.__getattr__(name) if value is not None: # Can't do if not value, b/c value might be '0' or "" return value else: return default def ShortestUniquePrefixes(self, fl): """Returns: dictionary; maps flag names to their shortest unique prefix.""" # Sort the list of flag names sorted_flags = [] for name, flag in fl.items(): sorted_flags.append(name) if flag.boolean: sorted_flags.append('no%s' % name) sorted_flags.sort() # For each name in the sorted list, determine the shortest unique # prefix by comparing itself to the next name and to the previous # name (the latter check uses cached info from the previous loop). shortest_matches = {} prev_idx = 0 for flag_idx in range(len(sorted_flags)): curr = sorted_flags[flag_idx] if flag_idx == (len(sorted_flags) - 1): next = None else: next = sorted_flags[flag_idx+1] next_len = len(next) for curr_idx in range(len(curr)): if (next is None or curr_idx >= next_len or curr[curr_idx] != next[curr_idx]): # curr longer than next or no more chars in common shortest_matches[curr] = curr[:max(prev_idx, curr_idx) + 1] prev_idx = curr_idx break else: # curr shorter than (or equal to) next shortest_matches[curr] = curr prev_idx = curr_idx + 1 # next will need at least one more char return shortest_matches def __IsFlagFileDirective(self, flag_string): """Checks whether flag_string contain a --flagfile=<foo> directive.""" if isinstance(flag_string, type("")): if flag_string.startswith('--flagfile='): return 1 elif flag_string == '--flagfile': return 1 elif flag_string.startswith('-flagfile='): return 1 elif flag_string == '-flagfile': return 1 else: return 0 return 0 def ExtractFilename(self, flagfile_str): """Returns filename from a flagfile_str of form -[-]flagfile=filename. The cases of --flagfile foo and -flagfile foo shouldn't be hitting this function, as they are dealt with in the level above this function. """ if flagfile_str.startswith('--flagfile='): return os.path.expanduser((flagfile_str[(len('--flagfile=')):]).strip()) elif flagfile_str.startswith('-flagfile='): return os.path.expanduser((flagfile_str[(len('-flagfile=')):]).strip()) else: raise FlagsError('Hit illegal --flagfile type: %s' % flagfile_str) def __GetFlagFileLines(self, filename, parsed_file_list): """Returns the useful (!=comments, etc) lines from a file with flags. Args: filename: A string, the name of the flag file. parsed_file_list: A list of the names of the files we have already read. MUTATED BY THIS FUNCTION. Returns: List of strings. See the note below. NOTE(springer): This function checks for a nested --flagfile=<foo> tag and handles the lower file recursively. It returns a list of all the lines that _could_ contain command flags. This is EVERYTHING except whitespace lines and comments (lines starting with '#' or '//'). """ line_list = [] # All line from flagfile. flag_line_list = [] # Subset of lines w/o comments, blanks, flagfile= tags. try: file_obj = open(filename, 'r') except IOError, e_msg: print e_msg print 'ERROR:: Unable to open flagfile: %s' % (filename) return flag_line_list line_list = file_obj.readlines() file_obj.close() parsed_file_list.append(filename) # This is where we check each line in the file we just read. for line in line_list: if line.isspace(): pass # Checks for comment (a line that starts with '#'). elif line.startswith('#') or line.startswith('//'): pass # Checks for a nested "--flagfile=<bar>" flag in the current file. # If we find one, recursively parse down into that file. elif self.__IsFlagFileDirective(line): sub_filename = self.ExtractFilename(line) # We do a little safety check for reparsing a file we've already done. if not sub_filename in parsed_file_list: included_flags = self.__GetFlagFileLines(sub_filename, parsed_file_list) flag_line_list.extend(included_flags) else: # Case of hitting a circularly included file. print >>sys.stderr, ('Warning: Hit circular flagfile dependency: %s' % sub_filename) else: # Any line that's not a comment or a nested flagfile should get # copied into 2nd position. This leaves earlier arguements # further back in the list, thus giving them higher priority. flag_line_list.append(line.strip()) return flag_line_list def ReadFlagsFromFiles(self, argv, force_gnu=True): """Processes command line args, but also allow args to be read from file. Args: argv: A list of strings, usually sys.argv[1:], which may contain one or more flagfile directives of the form --flagfile="./filename". Note that the name of the program (sys.argv[0]) should be omitted. force_gnu: If False, --flagfile parsing obeys normal flag semantics. If True, --flagfile parsing instead follows gnu_getopt semantics. *** WARNING *** force_gnu=False may become the future default! Returns: A new list which has the original list combined with what we read from any flagfile(s). References: Global gflags.FLAG class instance. This function should be called before the normal FLAGS(argv) call. This function scans the input list for a flag that looks like: --flagfile=<somefile>. Then it opens <somefile>, reads all valid key and value pairs and inserts them into the input list between the first item of the list and any subsequent items in the list. Note that your application's flags are still defined the usual way using gflags DEFINE_flag() type functions. Notes (assuming we're getting a commandline of some sort as our input): --> Flags from the command line argv _should_ always take precedence! --> A further "--flagfile=<otherfile.cfg>" CAN be nested in a flagfile. It will be processed after the parent flag file is done. --> For duplicate flags, first one we hit should "win". --> In a flagfile, a line beginning with # or // is a comment. --> Entirely blank lines _should_ be ignored. """ parsed_file_list = [] rest_of_args = argv new_argv = [] while rest_of_args: current_arg = rest_of_args[0] rest_of_args = rest_of_args[1:] if self.__IsFlagFileDirective(current_arg): # This handles the case of -(-)flagfile foo. In this case the # next arg really is part of this one. if current_arg == '--flagfile' or current_arg == '-flagfile': if not rest_of_args: raise IllegalFlagValue('--flagfile with no argument') flag_filename = os.path.expanduser(rest_of_args[0]) rest_of_args = rest_of_args[1:] else: # This handles the case of (-)-flagfile=foo. flag_filename = self.ExtractFilename(current_arg) new_argv[0:0] = self.__GetFlagFileLines(flag_filename, parsed_file_list) else: new_argv.append(current_arg) # Stop parsing after '--', like getopt and gnu_getopt. if current_arg == '--': break # Stop parsing after a non-flag, like getopt. if not current_arg.startswith('-'): if not force_gnu and not self.__dict__['__use_gnu_getopt']: break if rest_of_args: new_argv.extend(rest_of_args) return new_argv def FlagsIntoString(self): """Returns a string with the flags assignments from this FlagValues object. This function ignores flags whose value is None. Each flag assignment is separated by a newline. NOTE: MUST mirror the behavior of the C++ function CommandlineFlagsIntoString from google3/base/commandlineflags.cc. """ s = '' for flag in self.FlagDict().values(): if flag.value is not None: s += flag.Serialize() + '\n' return s def AppendFlagsIntoFile(self, filename): """Appends all flags assignments from this FlagInfo object to a file. Output will be in the format of a flagfile. NOTE: MUST mirror the behavior of the C++ version of AppendFlagsIntoFile from google3/base/commandlineflags.cc. """ out_file = open(filename, 'a') out_file.write(self.FlagsIntoString()) out_file.close() def WriteHelpInXMLFormat(self, outfile=None): """Outputs flag documentation in XML format. NOTE: We use element names that are consistent with those used by the C++ command-line flag library, from google3/base/commandlineflags_reporting.cc. We also use a few new elements (e.g., <key>), but we do not interfere / overlap with existing XML elements used by the C++ library. Please maintain this consistency. Args: outfile: File object we write to. Default None means sys.stdout. """ outfile = outfile or sys.stdout outfile.write('<?xml version=\"1.0\"?>\n') outfile.write('<AllFlags>\n') indent = ' ' _WriteSimpleXMLElement(outfile, 'program', os.path.basename(sys.argv[0]), indent) usage_doc = sys.modules['__main__'].__doc__ if not usage_doc: usage_doc = '\nUSAGE: %s [flags]\n' % sys.argv[0] else: usage_doc = usage_doc.replace('%s', sys.argv[0]) _WriteSimpleXMLElement(outfile, 'usage', usage_doc, indent) # Get list of key flags for the main module. key_flags = self._GetKeyFlagsForModule(_GetMainModule()) # Sort flags by declaring module name and next by flag name. flags_by_module = self.FlagsByModuleDict() all_module_names = list(flags_by_module.keys()) all_module_names.sort() for module_name in all_module_names: flag_list = [(f.name, f) for f in flags_by_module[module_name]] flag_list.sort() for unused_flag_name, flag in flag_list: is_key = flag in key_flags flag.WriteInfoInXMLFormat(outfile, module_name, is_key=is_key, indent=indent) outfile.write('</AllFlags>\n') outfile.flush() def AddValidator(self, validator): """Register new flags validator to be checked. Args: validator: gflags_validators.Validator Raises: AttributeError: if validators work with a non-existing flag. """ for flag_name in validator.GetFlagsNames(): flag = self.FlagDict()[flag_name] flag.validators.append(validator) # end of FlagValues definition # The global FlagValues instance FLAGS = FlagValues() def _MakeXMLSafe(s): """Escapes <, >, and & from s, and removes XML 1.0-illegal chars.""" s = cgi.escape(s) # Escape <, >, and & # Remove characters that cannot appear in an XML 1.0 document # (http://www.w3.org/TR/REC-xml/#charsets). # # NOTE: if there are problems with current solution, one may move to # XML 1.1, which allows such chars, if they're entity-escaped (&#xHH;). s = re.sub(r'[\x00-\x08\x0b\x0c\x0e-\x1f]', '', s) return s def _WriteSimpleXMLElement(outfile, name, value, indent): """Writes a simple XML element. Args: outfile: File object we write the XML element to. name: A string, the name of XML element. value: A Python object, whose string representation will be used as the value of the XML element. indent: A string, prepended to each line of generated output. """ value_str = str(value) if isinstance(value, bool): # Display boolean values as the C++ flag library does: no caps. value_str = value_str.lower() outfile.write('%s<%s>%s</%s>\n' % (indent, name, _MakeXMLSafe(value_str), name)) class Flag: """Information about a command-line flag. 'Flag' objects define the following fields: .name - the name for this flag .default - the default value for this flag .default_as_str - default value as repr'd string, e.g., "'true'" (or None) .value - the most recent parsed value of this flag; set by Parse() .help - a help string or None if no help is available .short_name - the single letter alias for this flag (or None) .boolean - if 'true', this flag does not accept arguments .present - true if this flag was parsed from command line flags. .parser - an ArgumentParser object .serializer - an ArgumentSerializer object .allow_override - the flag may be redefined without raising an error The only public method of a 'Flag' object is Parse(), but it is typically only called by a 'FlagValues' object. The Parse() method is a thin wrapper around the 'ArgumentParser' Parse() method. The parsed value is saved in .value, and the .present attribute is updated. If this flag was already present, a FlagsError is raised. Parse() is also called during __init__ to parse the default value and initialize the .value attribute. This enables other python modules to safely use flags even if the __main__ module neglects to parse the command line arguments. The .present attribute is cleared after __init__ parsing. If the default value is set to None, then the __init__ parsing step is skipped and the .value attribute is initialized to None. Note: The default value is also presented to the user in the help string, so it is important that it be a legal value for this flag. """ def __init__(self, parser, serializer, name, default, help_string, short_name=None, boolean=0, allow_override=0): self.name = name if not help_string: help_string = '(no help available)' self.help = help_string self.short_name = short_name self.boolean = boolean self.present = 0 self.parser = parser self.serializer = serializer self.allow_override = allow_override self.value = None self.validators = [] self.SetDefault(default) def __GetParsedValueAsString(self, value): if value is None: return None if self.serializer: return repr(self.serializer.Serialize(value)) if self.boolean: if value: return repr('true') else: return repr('false') return repr(str(value)) def Parse(self, argument): try: self.value = self.parser.Parse(argument) except ValueError, e: # recast ValueError as IllegalFlagValue raise IllegalFlagValue("flag --%s=%s: %s" % (self.name, argument, e)) self.present += 1 def Unparse(self): if self.default is None: self.value = None else: self.Parse(self.default) self.present = 0 def Serialize(self): if self.value is None: return '' if self.boolean: if self.value: return "--%s" % self.name else: return "--no%s" % self.name else: if not self.serializer: raise FlagsError("Serializer not present for flag %s" % self.name) return "--%s=%s" % (self.name, self.serializer.Serialize(self.value)) def SetDefault(self, value): """Changes the default value (and current value too) for this Flag.""" # We can't allow a None override because it may end up not being # passed to C++ code when we're overriding C++ flags. So we # cowardly bail out until someone fixes the semantics of trying to # pass None to a C++ flag. See swig_flags.Init() for details on # this behavior. # TODO(olexiy): Users can directly call this method, bypassing all flags # validators (we don't have FlagValues here, so we can not check # validators). # The simplest solution I see is to make this method private. # Another approach would be to store reference to the corresponding # FlagValues with each flag, but this seems to be an overkill. if value is None and self.allow_override: raise DuplicateFlagCannotPropagateNoneToSwig(self.name) self.default = value self.Unparse() self.default_as_str = self.__GetParsedValueAsString(self.value) def Type(self): """Returns: a string that describes the type of this Flag.""" # NOTE: we use strings, and not the types.*Type constants because # our flags can have more exotic types, e.g., 'comma separated list # of strings', 'whitespace separated list of strings', etc. return self.parser.Type() def WriteInfoInXMLFormat(self, outfile, module_name, is_key=False, indent=''): """Writes common info about this flag, in XML format. This is information that is relevant to all flags (e.g., name, meaning, etc.). If you defined a flag that has some other pieces of info, then please override _WriteCustomInfoInXMLFormat. Please do NOT override this method. Args: outfile: File object we write to. module_name: A string, the name of the module that defines this flag. is_key: A boolean, True iff this flag is key for main module. indent: A string that is prepended to each generated line. """ outfile.write(indent + '<flag>\n') inner_indent = indent + ' ' if is_key: _WriteSimpleXMLElement(outfile, 'key', 'yes', inner_indent) _WriteSimpleXMLElement(outfile, 'file', module_name, inner_indent) # Print flag features that are relevant for all flags. _WriteSimpleXMLElement(outfile, 'name', self.name, inner_indent) if self.short_name: _WriteSimpleXMLElement(outfile, 'short_name', self.short_name, inner_indent) if self.help: _WriteSimpleXMLElement(outfile, 'meaning', self.help, inner_indent) # The default flag value can either be represented as a string like on the # command line, or as a Python object. We serialize this value in the # latter case in order to remain consistent. if self.serializer and not isinstance(self.default, str): default_serialized = self.serializer.Serialize(self.default) else: default_serialized = self.default _WriteSimpleXMLElement(outfile, 'default', default_serialized, inner_indent) _WriteSimpleXMLElement(outfile, 'current', self.value, inner_indent) _WriteSimpleXMLElement(outfile, 'type', self.Type(), inner_indent) # Print extra flag features this flag may have. self._WriteCustomInfoInXMLFormat(outfile, inner_indent) outfile.write(indent + '</flag>\n') def _WriteCustomInfoInXMLFormat(self, outfile, indent): """Writes extra info about this flag, in XML format. "Extra" means "not already printed by WriteInfoInXMLFormat above." Args: outfile: File object we write to. indent: A string that is prepended to each generated line. """ # Usually, the parser knows the extra details about the flag, so # we just forward the call to it. self.parser.WriteCustomInfoInXMLFormat(outfile, indent) # End of Flag definition class _ArgumentParserCache(type): """Metaclass used to cache and share argument parsers among flags.""" _instances = {} def __call__(mcs, *args, **kwargs): """Returns an instance of the argument parser cls. This method overrides behavior of the __new__ methods in all subclasses of ArgumentParser (inclusive). If an instance for mcs with the same set of arguments exists, this instance is returned, otherwise a new instance is created. If any keyword arguments are defined, or the values in args are not hashable, this method always returns a new instance of cls. Args: args: Positional initializer arguments. kwargs: Initializer keyword arguments. Returns: An instance of cls, shared or new. """ if kwargs: return type.__call__(mcs, *args, **kwargs) else: instances = mcs._instances key = (mcs,) + tuple(args) try: return instances[key] except KeyError: # No cache entry for key exists, create a new one. return instances.setdefault(key, type.__call__(mcs, *args)) except TypeError: # An object in args cannot be hashed, always return # a new instance. return type.__call__(mcs, *args) class ArgumentParser(object): """Base class used to parse and convert arguments. The Parse() method checks to make sure that the string argument is a legal value and convert it to a native type. If the value cannot be converted, it should throw a 'ValueError' exception with a human readable explanation of why the value is illegal. Subclasses should also define a syntactic_help string which may be presented to the user to describe the form of the legal values. Argument parser classes must be stateless, since instances are cached and shared between flags. Initializer arguments are allowed, but all member variables must be derived from initializer arguments only. """ __metaclass__ = _ArgumentParserCache syntactic_help = "" def Parse(self, argument): """Default implementation: always returns its argument unmodified.""" return argument def Type(self): return 'string' def WriteCustomInfoInXMLFormat(self, outfile, indent): pass class ArgumentSerializer: """Base class for generating string representations of a flag value.""" def Serialize(self, value): return str(value) class ListSerializer(ArgumentSerializer): def __init__(self, list_sep): self.list_sep = list_sep def Serialize(self, value): return self.list_sep.join([str(x) for x in value]) # Flags validators def RegisterValidator(flag_name, checker, message='Flag validation failed', flag_values=FLAGS): """Adds a constraint, which will be enforced during program execution. The constraint is validated when flags are initially parsed, and after each change of the corresponding flag's value. Args: flag_name: string, name of the flag to be checked. checker: method to validate the flag. input - value of the corresponding flag (string, boolean, etc. This value will be passed to checker by the library). See file's docstring for examples. output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise gflags_validators.Error(desired_error_message). message: error text to be shown to the user if checker returns False. If checker raises gflags_validators.Error, message from the raised Error will be shown. flag_values: FlagValues Raises: AttributeError: if flag_name is not registered as a valid flag name. """ flag_values.AddValidator(gflags_validators.SimpleValidator(flag_name, checker, message)) def MarkFlagAsRequired(flag_name, flag_values=FLAGS): """Ensure that flag is not None during program execution. Registers a flag validator, which will follow usual validator rules. Args: flag_name: string, name of the flag flag_values: FlagValues Raises: AttributeError: if flag_name is not registered as a valid flag name. """ RegisterValidator(flag_name, lambda value: value is not None, message='Flag --%s must be specified.' % flag_name, flag_values=flag_values) def _RegisterBoundsValidatorIfNeeded(parser, name, flag_values): """Enforce lower and upper bounds for numeric flags. Args: parser: NumericParser (either FloatParser or IntegerParser). Provides lower and upper bounds, and help text to display. name: string, name of the flag flag_values: FlagValues """ if parser.lower_bound is not None or parser.upper_bound is not None: def Checker(value): if value is not None and parser.IsOutsideBounds(value): message = '%s is not %s' % (value, parser.syntactic_help) raise gflags_validators.Error(message) return True RegisterValidator(name, Checker, flag_values=flag_values) # The DEFINE functions are explained in mode details in the module doc string. def DEFINE(parser, name, default, help, flag_values=FLAGS, serializer=None, **args): """Registers a generic Flag object. NOTE: in the docstrings of all DEFINE* functions, "registers" is short for "creates a new flag and registers it". Auxiliary function: clients should use the specialized DEFINE_<type> function instead. Args: parser: ArgumentParser that is used to parse the flag arguments. name: A string, the flag name. default: The default value of the flag. help: A help string. flag_values: FlagValues object the flag will be registered with. serializer: ArgumentSerializer that serializes the flag value. args: Dictionary with extra keyword args that are passes to the Flag __init__. """ DEFINE_flag(Flag(parser, serializer, name, default, help, **args), flag_values) def DEFINE_flag(flag, flag_values=FLAGS): """Registers a 'Flag' object with a 'FlagValues' object. By default, the global FLAGS 'FlagValue' object is used. Typical users will use one of the more specialized DEFINE_xxx functions, such as DEFINE_string or DEFINE_integer. But developers who need to create Flag objects themselves should use this function to register their flags. """ # copying the reference to flag_values prevents pychecker warnings fv = flag_values fv[flag.name] = flag # Tell flag_values who's defining the flag. if isinstance(flag_values, FlagValues): # Regarding the above isinstance test: some users pass funny # values of flag_values (e.g., {}) in order to avoid the flag # registration (in the past, there used to be a flag_values == # FLAGS test here) and redefine flags with the same name (e.g., # debug). To avoid breaking their code, we perform the # registration only if flag_values is a real FlagValues object. flag_values._RegisterFlagByModule(_GetCallingModule(), flag) def _InternalDeclareKeyFlags(flag_names, flag_values=FLAGS, key_flag_values=None): """Declares a flag as key for the calling module. Internal function. User code should call DECLARE_key_flag or ADOPT_module_key_flags instead. Args: flag_names: A list of strings that are names of already-registered Flag objects. flag_values: A FlagValues object that the flags listed in flag_names have registered with (the value of the flag_values argument from the DEFINE_* calls that defined those flags). This should almost never need to be overridden. key_flag_values: A FlagValues object that (among possibly many other things) keeps track of the key flags for each module. Default None means "same as flag_values". This should almost never need to be overridden. Raises: UnrecognizedFlagError: when we refer to a flag that was not defined yet. """ key_flag_values = key_flag_values or flag_values module = _GetCallingModule() for flag_name in flag_names: if flag_name not in flag_values: raise UnrecognizedFlagError(flag_name) flag = flag_values.FlagDict()[flag_name] key_flag_values._RegisterKeyFlagForModule(module, flag) def DECLARE_key_flag(flag_name, flag_values=FLAGS): """Declares one flag as key to the current module. Key flags are flags that are deemed really important for a module. They are important when listing help messages; e.g., if the --helpshort command-line flag is used, then only the key flags of the main module are listed (instead of all flags, as in the case of --help). Sample usage: flags.DECLARED_key_flag('flag_1') Args: flag_name: A string, the name of an already declared flag. (Redeclaring flags as key, including flags implicitly key because they were declared in this module, is a no-op.) flag_values: A FlagValues object. This should almost never need to be overridden. """ if flag_name in _SPECIAL_FLAGS: # Take care of the special flags, e.g., --flagfile, --undefok. # These flags are defined in _SPECIAL_FLAGS, and are treated # specially during flag parsing, taking precedence over the # user-defined flags. _InternalDeclareKeyFlags([flag_name], flag_values=_SPECIAL_FLAGS, key_flag_values=flag_values) return _InternalDeclareKeyFlags([flag_name], flag_values=flag_values) def ADOPT_module_key_flags(module, flag_values=FLAGS): """Declares that all flags key to a module are key to the current module. Args: module: A module object. flag_values: A FlagValues object. This should almost never need to be overridden. Raises: FlagsError: When given an argument that is a module name (a string), instead of a module object. """ # NOTE(salcianu): an even better test would be if not # isinstance(module, types.ModuleType) but I didn't want to import # types for such a tiny use. if isinstance(module, str): raise FlagsError('Received module name %s; expected a module object.' % module) _InternalDeclareKeyFlags( [f.name for f in flag_values._GetKeyFlagsForModule(module.__name__)], flag_values=flag_values) # If module is this flag module, take _SPECIAL_FLAGS into account. if module == _GetThisModuleObjectAndName()[0]: _InternalDeclareKeyFlags( # As we associate flags with _GetCallingModule(), the special # flags defined in this module are incorrectly registered with # a different module. So, we can't use _GetKeyFlagsForModule. # Instead, we take all flags from _SPECIAL_FLAGS (a private # FlagValues, where no other module should register flags). [f.name for f in _SPECIAL_FLAGS.FlagDict().values()], flag_values=_SPECIAL_FLAGS, key_flag_values=flag_values) # # STRING FLAGS # def DEFINE_string(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value can be any string.""" parser = ArgumentParser() serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) # # BOOLEAN FLAGS # # and the special HELP flags. class BooleanParser(ArgumentParser): """Parser of boolean values.""" def Convert(self, argument): """Converts the argument to a boolean; raise ValueError on errors.""" if type(argument) == str: if argument.lower() in ['true', 't', '1']: return True elif argument.lower() in ['false', 'f', '0']: return False bool_argument = bool(argument) if argument == bool_argument: # The argument is a valid boolean (True, False, 0, or 1), and not just # something that always converts to bool (list, string, int, etc.). return bool_argument raise ValueError('Non-boolean argument to boolean flag', argument) def Parse(self, argument): val = self.Convert(argument) return val def Type(self): return 'bool' class BooleanFlag(Flag): """Basic boolean flag. Boolean flags do not take any arguments, and their value is either True (1) or False (0). The false value is specified on the command line by prepending the word 'no' to either the long or the short flag name. For example, if a Boolean flag was created whose long name was 'update' and whose short name was 'x', then this flag could be explicitly unset through either --noupdate or --nox. """ def __init__(self, name, default, help, short_name=None, **args): p = BooleanParser() Flag.__init__(self, p, None, name, default, help, short_name, 1, **args) if not self.help: self.help = "a boolean value" def DEFINE_boolean(name, default, help, flag_values=FLAGS, **args): """Registers a boolean flag. Such a boolean flag does not take an argument. If a user wants to specify a false value explicitly, the long option beginning with 'no' must be used: i.e. --noflag This flag will have a value of None, True or False. None is possible if default=None and the user does not specify the flag on the command line. """ DEFINE_flag(BooleanFlag(name, default, help, **args), flag_values) # Match C++ API to unconfuse C++ people. DEFINE_bool = DEFINE_boolean class HelpFlag(BooleanFlag): """ HelpFlag is a special boolean flag that prints usage information and raises a SystemExit exception if it is ever found in the command line arguments. Note this is called with allow_override=1, so other apps can define their own --help flag, replacing this one, if they want. """ def __init__(self): BooleanFlag.__init__(self, "help", 0, "show this help", short_name="?", allow_override=1) def Parse(self, arg): if arg: doc = sys.modules["__main__"].__doc__ flags = str(FLAGS) print doc or ("\nUSAGE: %s [flags]\n" % sys.argv[0]) if flags: print "flags:" print flags sys.exit(1) class HelpXMLFlag(BooleanFlag): """Similar to HelpFlag, but generates output in XML format.""" def __init__(self): BooleanFlag.__init__(self, 'helpxml', False, 'like --help, but generates XML output', allow_override=1) def Parse(self, arg): if arg: FLAGS.WriteHelpInXMLFormat(sys.stdout) sys.exit(1) class HelpshortFlag(BooleanFlag): """ HelpshortFlag is a special boolean flag that prints usage information for the "main" module, and rasies a SystemExit exception if it is ever found in the command line arguments. Note this is called with allow_override=1, so other apps can define their own --helpshort flag, replacing this one, if they want. """ def __init__(self): BooleanFlag.__init__(self, "helpshort", 0, "show usage only for this module", allow_override=1) def Parse(self, arg): if arg: doc = sys.modules["__main__"].__doc__ flags = FLAGS.MainModuleHelp() print doc or ("\nUSAGE: %s [flags]\n" % sys.argv[0]) if flags: print "flags:" print flags sys.exit(1) # # Numeric parser - base class for Integer and Float parsers # class NumericParser(ArgumentParser): """Parser of numeric values. Parsed value may be bounded to a given upper and lower bound. """ def IsOutsideBounds(self, val): return ((self.lower_bound is not None and val < self.lower_bound) or (self.upper_bound is not None and val > self.upper_bound)) def Parse(self, argument): val = self.Convert(argument) if self.IsOutsideBounds(val): raise ValueError("%s is not %s" % (val, self.syntactic_help)) return val def WriteCustomInfoInXMLFormat(self, outfile, indent): if self.lower_bound is not None: _WriteSimpleXMLElement(outfile, 'lower_bound', self.lower_bound, indent) if self.upper_bound is not None: _WriteSimpleXMLElement(outfile, 'upper_bound', self.upper_bound, indent) def Convert(self, argument): """Default implementation: always returns its argument unmodified.""" return argument # End of Numeric Parser # # FLOAT FLAGS # class FloatParser(NumericParser): """Parser of floating point values. Parsed value may be bounded to a given upper and lower bound. """ number_article = "a" number_name = "number" syntactic_help = " ".join((number_article, number_name)) def __init__(self, lower_bound=None, upper_bound=None): super(FloatParser, self).__init__() self.lower_bound = lower_bound self.upper_bound = upper_bound sh = self.syntactic_help if lower_bound is not None and upper_bound is not None: sh = ("%s in the range [%s, %s]" % (sh, lower_bound, upper_bound)) elif lower_bound == 0: sh = "a non-negative %s" % self.number_name elif upper_bound == 0: sh = "a non-positive %s" % self.number_name elif upper_bound is not None: sh = "%s <= %s" % (self.number_name, upper_bound) elif lower_bound is not None: sh = "%s >= %s" % (self.number_name, lower_bound) self.syntactic_help = sh def Convert(self, argument): """Converts argument to a float; raises ValueError on errors.""" return float(argument) def Type(self): return 'float' # End of FloatParser def DEFINE_float(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value must be a float. If lower_bound or upper_bound are set, then this flag must be within the given range. """ parser = FloatParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) _RegisterBoundsValidatorIfNeeded(parser, name, flag_values=flag_values) # # INTEGER FLAGS # class IntegerParser(NumericParser): """Parser of an integer value. Parsed value may be bounded to a given upper and lower bound. """ number_article = "an" number_name = "integer" syntactic_help = " ".join((number_article, number_name)) def __init__(self, lower_bound=None, upper_bound=None): super(IntegerParser, self).__init__() self.lower_bound = lower_bound self.upper_bound = upper_bound sh = self.syntactic_help if lower_bound is not None and upper_bound is not None: sh = ("%s in the range [%s, %s]" % (sh, lower_bound, upper_bound)) elif lower_bound == 1: sh = "a positive %s" % self.number_name elif upper_bound == -1: sh = "a negative %s" % self.number_name elif lower_bound == 0: sh = "a non-negative %s" % self.number_name elif upper_bound == 0: sh = "a non-positive %s" % self.number_name elif upper_bound is not None: sh = "%s <= %s" % (self.number_name, upper_bound) elif lower_bound is not None: sh = "%s >= %s" % (self.number_name, lower_bound) self.syntactic_help = sh def Convert(self, argument): __pychecker__ = 'no-returnvalues' if type(argument) == str: base = 10 if len(argument) > 2 and argument[0] == "0" and argument[1] == "x": base = 16 try: return int(argument, base) # ValueError is thrown when argument is a string, and overflows an int. except ValueError: return long(argument, base) else: try: return int(argument) # OverflowError is thrown when argument is numeric, and overflows an int. except OverflowError: return long(argument) def Type(self): return 'int' def DEFINE_integer(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value must be an integer. If lower_bound, or upper_bound are set, then this flag must be within the given range. """ parser = IntegerParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) _RegisterBoundsValidatorIfNeeded(parser, name, flag_values=flag_values) # # ENUM FLAGS # class EnumParser(ArgumentParser): """Parser of a string enum value (a string value from a given set). If enum_values (see below) is not specified, any string is allowed. """ def __init__(self, enum_values=None): super(EnumParser, self).__init__() self.enum_values = enum_values def Parse(self, argument): if self.enum_values and argument not in self.enum_values: raise ValueError("value should be one of <%s>" % "|".join(self.enum_values)) return argument def Type(self): return 'string enum' class EnumFlag(Flag): """Basic enum flag; its value can be any string from list of enum_values.""" def __init__(self, name, default, help, enum_values=None, short_name=None, **args): enum_values = enum_values or [] p = EnumParser(enum_values) g = ArgumentSerializer() Flag.__init__(self, p, g, name, default, help, short_name, **args) if not self.help: self.help = "an enum string" self.help = "<%s>: %s" % ("|".join(enum_values), self.help) def _WriteCustomInfoInXMLFormat(self, outfile, indent): for enum_value in self.parser.enum_values: _WriteSimpleXMLElement(outfile, 'enum_value', enum_value, indent) def DEFINE_enum(name, default, enum_values, help, flag_values=FLAGS, **args): """Registers a flag whose value can be any string from enum_values.""" DEFINE_flag(EnumFlag(name, default, help, enum_values, ** args), flag_values) # # LIST FLAGS # class BaseListParser(ArgumentParser): """Base class for a parser of lists of strings. To extend, inherit from this class; from the subclass __init__, call BaseListParser.__init__(self, token, name) where token is a character used to tokenize, and name is a description of the separator. """ def __init__(self, token=None, name=None): assert name super(BaseListParser, self).__init__() self._token = token self._name = name self.syntactic_help = "a %s separated list" % self._name def Parse(self, argument): if isinstance(argument, list): return argument elif argument == '': return [] else: return [s.strip() for s in argument.split(self._token)] def Type(self): return '%s separated list of strings' % self._name class ListParser(BaseListParser): """Parser for a comma-separated list of strings.""" def __init__(self): BaseListParser.__init__(self, ',', 'comma') def WriteCustomInfoInXMLFormat(self, outfile, indent): BaseListParser.WriteCustomInfoInXMLFormat(self, outfile, indent) _WriteSimpleXMLElement(outfile, 'list_separator', repr(','), indent) class WhitespaceSeparatedListParser(BaseListParser): """Parser for a whitespace-separated list of strings.""" def __init__(self): BaseListParser.__init__(self, None, 'whitespace') def WriteCustomInfoInXMLFormat(self, outfile, indent): BaseListParser.WriteCustomInfoInXMLFormat(self, outfile, indent) separators = list(string.whitespace) separators.sort() for ws_char in string.whitespace: _WriteSimpleXMLElement(outfile, 'list_separator', repr(ws_char), indent) def DEFINE_list(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value is a comma-separated list of strings.""" parser = ListParser() serializer = ListSerializer(',') DEFINE(parser, name, default, help, flag_values, serializer, **args) def DEFINE_spaceseplist(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value is a whitespace-separated list of strings. Any whitespace can be used as a separator. """ parser = WhitespaceSeparatedListParser() serializer = ListSerializer(' ') DEFINE(parser, name, default, help, flag_values, serializer, **args) # # MULTI FLAGS # class MultiFlag(Flag): """A flag that can appear multiple time on the command-line. The value of such a flag is a list that contains the individual values from all the appearances of that flag on the command-line. See the __doc__ for Flag for most behavior of this class. Only differences in behavior are described here: * The default value may be either a single value or a list of values. A single value is interpreted as the [value] singleton list. * The value of the flag is always a list, even if the option was only supplied once, and even if the default value is a single value """ def __init__(self, *args, **kwargs): Flag.__init__(self, *args, **kwargs) self.help += ';\n repeat this option to specify a list of values' def Parse(self, arguments): """Parses one or more arguments with the installed parser. Args: arguments: a single argument or a list of arguments (typically a list of default values); a single argument is converted internally into a list containing one item. """ if not isinstance(arguments, list): # Default value may be a list of values. Most other arguments # will not be, so convert them into a single-item list to make # processing simpler below. arguments = [arguments] if self.present: # keep a backup reference to list of previously supplied option values values = self.value else: # "erase" the defaults with an empty list values = [] for item in arguments: # have Flag superclass parse argument, overwriting self.value reference Flag.Parse(self, item) # also increments self.present values.append(self.value) # put list of option values back in the 'value' attribute self.value = values def Serialize(self): if not self.serializer: raise FlagsError("Serializer not present for flag %s" % self.name) if self.value is None: return '' s = '' multi_value = self.value for self.value in multi_value: if s: s += ' ' s += Flag.Serialize(self) self.value = multi_value return s def Type(self): return 'multi ' + self.parser.Type() def DEFINE_multi(parser, serializer, name, default, help, flag_values=FLAGS, **args): """Registers a generic MultiFlag that parses its args with a given parser. Auxiliary function. Normal users should NOT use it directly. Developers who need to create their own 'Parser' classes for options which can appear multiple times can call this module function to register their flags. """ DEFINE_flag(MultiFlag(parser, serializer, name, default, help, **args), flag_values) def DEFINE_multistring(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value can be a list of any strings. Use the flag on the command line multiple times to place multiple string values into the list. The 'default' may be a single string (which will be converted into a single-element list) or a list of strings. """ parser = ArgumentParser() serializer = ArgumentSerializer() DEFINE_multi(parser, serializer, name, default, help, flag_values, **args) def DEFINE_multi_int(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value can be a list of arbitrary integers. Use the flag on the command line multiple times to place multiple integer values into the list. The 'default' may be a single integer (which will be converted into a single-element list) or a list of integers. """ parser = IntegerParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE_multi(parser, serializer, name, default, help, flag_values, **args) # Now register the flags that we want to exist in all applications. # These are all defined with allow_override=1, so user-apps can use # these flagnames for their own purposes, if they want. DEFINE_flag(HelpFlag()) DEFINE_flag(HelpshortFlag()) DEFINE_flag(HelpXMLFlag()) # Define special flags here so that help may be generated for them. # NOTE: Please do NOT use _SPECIAL_FLAGS from outside this module. _SPECIAL_FLAGS = FlagValues() DEFINE_string( 'flagfile', "", "Insert flag definitions from the given file into the command line.", _SPECIAL_FLAGS) DEFINE_string( 'undefok', "", "comma-separated list of flag names that it is okay to specify " "on the command line even if the program does not define a flag " "with that name. IMPORTANT: flags in this list that have " "arguments MUST use the --flag=value format.", _SPECIAL_FLAGS)
Python
#!/usr/bin/env python # Copyright (c) 2010, Google Inc. # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. """Module to enforce different constraints on flags. A validator represents an invariant, enforced over a one or more flags. See 'FLAGS VALIDATORS' in flags.py's docstring for a usage manual. """ __author__ = 'olexiy@google.com (Olexiy Oryeshko)' class Error(Exception): """Thrown If validator constraint is not satisfied.""" class Validator(object): """Base class for flags validators. Users should NOT overload these classes, and use flags.Register... methods instead. """ # Used to assign each validator an unique insertion_index validators_count = 0 def __init__(self, checker, message): """Constructor to create all validators. Args: checker: function to verify the constraint. Input of this method varies, see SimpleValidator and DictionaryValidator for a detailed description. message: string, error message to be shown to the user """ self.checker = checker self.message = message Validator.validators_count += 1 # Used to assert validators in the order they were registered (CL/18694236) self.insertion_index = Validator.validators_count def Verify(self, flag_values): """Verify that constraint is satisfied. flags library calls this method to verify Validator's constraint. Args: flag_values: flags.FlagValues, containing all flags Raises: Error: if constraint is not satisfied. """ param = self._GetInputToCheckerFunction(flag_values) if not self.checker(param): raise Error(self.message) def GetFlagsNames(self): """Return the names of the flags checked by this validator. Returns: [string], names of the flags """ raise NotImplementedError('This method should be overloaded') def PrintFlagsWithValues(self, flag_values): raise NotImplementedError('This method should be overloaded') def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues, containing all flags. Returns: Return type depends on the specific validator. """ raise NotImplementedError('This method should be overloaded') class SimpleValidator(Validator): """Validator behind RegisterValidator() method. Validates that a single flag passes its checker function. The checker function takes the flag value and returns True (if value looks fine) or, if flag value is not valid, either returns False or raises an Exception.""" def __init__(self, flag_name, checker, message): """Constructor. Args: flag_name: string, name of the flag. checker: function to verify the validator. input - value of the corresponding flag (string, boolean, etc). output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise Error. message: string, error message to be shown to the user if validator's condition is not satisfied """ super(SimpleValidator, self).__init__(checker, message) self.flag_name = flag_name def GetFlagsNames(self): return [self.flag_name] def PrintFlagsWithValues(self, flag_values): return 'flag --%s=%s' % (self.flag_name, flag_values[self.flag_name].value) def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues Returns: value of the corresponding flag. """ return flag_values[self.flag_name].value class DictionaryValidator(Validator): """Validator behind RegisterDictionaryValidator method. Validates that flag values pass their common checker function. The checker function takes flag values and returns True (if values look fine) or, if values are not valid, either returns False or raises an Exception. """ def __init__(self, flag_names, checker, message): """Constructor. Args: flag_names: [string], containing names of the flags used by checker. checker: function to verify the validator. input - dictionary, with keys() being flag_names, and value for each key being the value of the corresponding flag (string, boolean, etc). output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise Error. message: string, error message to be shown to the user if validator's condition is not satisfied """ super(DictionaryValidator, self).__init__(checker, message) self.flag_names = flag_names def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues Returns: dictionary, with keys() being self.lag_names, and value for each key being the value of the corresponding flag (string, boolean, etc). """ return dict([key, flag_values[key].value] for key in self.flag_names) def PrintFlagsWithValues(self, flag_values): prefix = 'flags ' flags_with_values = [] for key in self.flag_names: flags_with_values.append('%s=%s' % (key, flag_values[key].value)) return prefix + ', '.join(flags_with_values) def GetFlagsNames(self): return self.flag_names
Python
#!/usr/bin/env python # Copyright (c) 2007, Google Inc. # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. # # --- # Author: Chad Lester # Design and style contributions by: # Amit Patel, Bogdan Cocosel, Daniel Dulitz, Eric Tiedemann, # Eric Veach, Laurence Gonsalves, Matthew Springer # Code reorganized a bit by Craig Silverstein """This module is used to define and parse command line flags. This module defines a *distributed* flag-definition policy: rather than an application having to define all flags in or near main(), each python module defines flags that are useful to it. When one python module imports another, it gains access to the other's flags. (This is implemented by having all modules share a common, global registry object containing all the flag information.) Flags are defined through the use of one of the DEFINE_xxx functions. The specific function used determines how the flag is parsed, checked, and optionally type-converted, when it's seen on the command line. IMPLEMENTATION: DEFINE_* creates a 'Flag' object and registers it with a 'FlagValues' object (typically the global FlagValues FLAGS, defined here). The 'FlagValues' object can scan the command line arguments and pass flag arguments to the corresponding 'Flag' objects for value-checking and type conversion. The converted flag values are available as attributes of the 'FlagValues' object. Code can access the flag through a FlagValues object, for instance gflags.FLAGS.myflag. Typically, the __main__ module passes the command line arguments to gflags.FLAGS for parsing. At bottom, this module calls getopt(), so getopt functionality is supported, including short- and long-style flags, and the use of -- to terminate flags. Methods defined by the flag module will throw 'FlagsError' exceptions. The exception argument will be a human-readable string. FLAG TYPES: This is a list of the DEFINE_*'s that you can do. All flags take a name, default value, help-string, and optional 'short' name (one-letter name). Some flags have other arguments, which are described with the flag. DEFINE_string: takes any input, and interprets it as a string. DEFINE_bool or DEFINE_boolean: typically does not take an argument: say --myflag to set FLAGS.myflag to true, or --nomyflag to set FLAGS.myflag to false. Alternately, you can say --myflag=true or --myflag=t or --myflag=1 or --myflag=false or --myflag=f or --myflag=0 DEFINE_float: takes an input and interprets it as a floating point number. Takes optional args lower_bound and upper_bound; if the number specified on the command line is out of range, it will raise a FlagError. DEFINE_integer: takes an input and interprets it as an integer. Takes optional args lower_bound and upper_bound as for floats. DEFINE_enum: takes a list of strings which represents legal values. If the command-line value is not in this list, raise a flag error. Otherwise, assign to FLAGS.flag as a string. DEFINE_list: Takes a comma-separated list of strings on the commandline. Stores them in a python list object. DEFINE_spaceseplist: Takes a space-separated list of strings on the commandline. Stores them in a python list object. Example: --myspacesepflag "foo bar baz" DEFINE_multistring: The same as DEFINE_string, except the flag can be specified more than once on the commandline. The result is a python list object (list of strings), even if the flag is only on the command line once. DEFINE_multi_int: The same as DEFINE_integer, except the flag can be specified more than once on the commandline. The result is a python list object (list of ints), even if the flag is only on the command line once. SPECIAL FLAGS: There are a few flags that have special meaning: --help prints a list of all the flags in a human-readable fashion --helpshort prints a list of all key flags (see below). --helpxml prints a list of all flags, in XML format. DO NOT parse the output of --help and --helpshort. Instead, parse the output of --helpxml. For more info, see "OUTPUT FOR --helpxml" below. --flagfile=foo read flags from file foo. --undefok=f1,f2 ignore unrecognized option errors for f1,f2. For boolean flags, you should use --undefok=boolflag, and --boolflag and --noboolflag will be accepted. Do not use --undefok=noboolflag. -- as in getopt(), terminates flag-processing FLAGS VALIDATORS: If your program: - requires flag X to be specified - needs flag Y to match a regular expression - or requires any more general constraint to be satisfied then validators are for you! Each validator represents a constraint over one flag, which is enforced starting from the initial parsing of the flags and until the program terminates. Also, lower_bound and upper_bound for numerical flags are enforced using flag validators. Howto: If you want to enforce a constraint over one flag, use flags.RegisterValidator(flag_name, checker, message='Flag validation failed', flag_values=FLAGS) After flag values are initially parsed, and after any change to the specified flag, method checker(flag_value) will be executed. If constraint is not satisfied, an IllegalFlagValue exception will be raised. See RegisterValidator's docstring for a detailed explanation on how to construct your own checker. EXAMPLE USAGE: FLAGS = flags.FLAGS flags.DEFINE_integer('my_version', 0, 'Version number.') flags.DEFINE_string('filename', None, 'Input file name', short_name='f') flags.RegisterValidator('my_version', lambda value: value % 2 == 0, message='--my_version must be divisible by 2') flags.MarkFlagAsRequired('filename') NOTE ON --flagfile: Flags may be loaded from text files in addition to being specified on the commandline. Any flags you don't feel like typing, throw them in a file, one flag per line, for instance: --myflag=myvalue --nomyboolean_flag You then specify your file with the special flag '--flagfile=somefile'. You CAN recursively nest flagfile= tokens OR use multiple files on the command line. Lines beginning with a single hash '#' or a double slash '//' are comments in your flagfile. Any flagfile=<file> will be interpreted as having a relative path from the current working directory rather than from the place the file was included from: myPythonScript.py --flagfile=config/somefile.cfg If somefile.cfg includes further --flagfile= directives, these will be referenced relative to the original CWD, not from the directory the including flagfile was found in! The caveat applies to people who are including a series of nested files in a different dir than they are executing out of. Relative path names are always from CWD, not from the directory of the parent include flagfile. We do now support '~' expanded directory names. Absolute path names ALWAYS work! EXAMPLE USAGE: import gflags FLAGS = gflags.FLAGS # Flag names are globally defined! So in general, we need to be # careful to pick names that are unlikely to be used by other libraries. # If there is a conflict, we'll get an error at import time. gflags.DEFINE_string('name', 'Mr. President', 'your name') gflags.DEFINE_integer('age', None, 'your age in years', lower_bound=0) gflags.DEFINE_boolean('debug', False, 'produces debugging output') gflags.DEFINE_enum('gender', 'male', ['male', 'female'], 'your gender') def main(argv): try: argv = FLAGS(argv) # parse flags except gflags.FlagsError, e: print '%s\\nUsage: %s ARGS\\n%s' % (e, sys.argv[0], FLAGS) sys.exit(1) if FLAGS.debug: print 'non-flag arguments:', argv print 'Happy Birthday', FLAGS.name if FLAGS.age is not None: print 'You are a %s, who is %d years old' % (FLAGS.gender, FLAGS.age) if __name__ == '__main__': main(sys.argv) KEY FLAGS: As we already explained, each module gains access to all flags defined by all the other modules it transitively imports. In the case of non-trivial scripts, this means a lot of flags ... For documentation purposes, it is good to identify the flags that are key (i.e., really important) to a module. Clearly, the concept of "key flag" is a subjective one. When trying to determine whether a flag is key to a module or not, assume that you are trying to explain your module to a potential user: which flags would you really like to mention first? We'll describe shortly how to declare which flags are key to a module. For the moment, assume we know the set of key flags for each module. Then, if you use the app.py module, you can use the --helpshort flag to print only the help for the flags that are key to the main module, in a human-readable format. NOTE: If you need to parse the flag help, do NOT use the output of --help / --helpshort. That output is meant for human consumption, and may be changed in the future. Instead, use --helpxml; flags that are key for the main module are marked there with a <key>yes</key> element. The set of key flags for a module M is composed of: 1. Flags defined by module M by calling a DEFINE_* function. 2. Flags that module M explictly declares as key by using the function DECLARE_key_flag(<flag_name>) 3. Key flags of other modules that M specifies by using the function ADOPT_module_key_flags(<other_module>) This is a "bulk" declaration of key flags: each flag that is key for <other_module> becomes key for the current module too. Notice that if you do not use the functions described at points 2 and 3 above, then --helpshort prints information only about the flags defined by the main module of our script. In many cases, this behavior is good enough. But if you move part of the main module code (together with the related flags) into a different module, then it is nice to use DECLARE_key_flag / ADOPT_module_key_flags and make sure --helpshort lists all relevant flags (otherwise, your code refactoring may confuse your users). Note: each of DECLARE_key_flag / ADOPT_module_key_flags has its own pluses and minuses: DECLARE_key_flag is more targeted and may lead a more focused --helpshort documentation. ADOPT_module_key_flags is good for cases when an entire module is considered key to the current script. Also, it does not require updates to client scripts when a new flag is added to the module. EXAMPLE USAGE 2 (WITH KEY FLAGS): Consider an application that contains the following three files (two auxiliary modules and a main module): File libfoo.py: import gflags gflags.DEFINE_integer('num_replicas', 3, 'Number of replicas to start') gflags.DEFINE_boolean('rpc2', True, 'Turn on the usage of RPC2.') ... some code ... File libbar.py: import gflags gflags.DEFINE_string('bar_gfs_path', '/gfs/path', 'Path to the GFS files for libbar.') gflags.DEFINE_string('email_for_bar_errors', 'bar-team@google.com', 'Email address for bug reports about module libbar.') gflags.DEFINE_boolean('bar_risky_hack', False, 'Turn on an experimental and buggy optimization.') ... some code ... File myscript.py: import gflags import libfoo import libbar gflags.DEFINE_integer('num_iterations', 0, 'Number of iterations.') # Declare that all flags that are key for libfoo are # key for this module too. gflags.ADOPT_module_key_flags(libfoo) # Declare that the flag --bar_gfs_path (defined in libbar) is key # for this module. gflags.DECLARE_key_flag('bar_gfs_path') ... some code ... When myscript is invoked with the flag --helpshort, the resulted help message lists information about all the key flags for myscript: --num_iterations, --num_replicas, --rpc2, and --bar_gfs_path (in addition to the special flags --help and --helpshort). Of course, myscript uses all the flags declared by it (in this case, just --num_replicas) or by any of the modules it transitively imports (e.g., the modules libfoo, libbar). E.g., it can access the value of FLAGS.bar_risky_hack, even if --bar_risky_hack is not declared as a key flag for myscript. OUTPUT FOR --helpxml: The --helpxml flag generates output with the following structure: <?xml version="1.0"?> <AllFlags> <program>PROGRAM_BASENAME</program> <usage>MAIN_MODULE_DOCSTRING</usage> (<flag> [<key>yes</key>] <file>DECLARING_MODULE</file> <name>FLAG_NAME</name> <meaning>FLAG_HELP_MESSAGE</meaning> <default>DEFAULT_FLAG_VALUE</default> <current>CURRENT_FLAG_VALUE</current> <type>FLAG_TYPE</type> [OPTIONAL_ELEMENTS] </flag>)* </AllFlags> Notes: 1. The output is intentionally similar to the output generated by the C++ command-line flag library. The few differences are due to the Python flags that do not have a C++ equivalent (at least not yet), e.g., DEFINE_list. 2. New XML elements may be added in the future. 3. DEFAULT_FLAG_VALUE is in serialized form, i.e., the string you can pass for this flag on the command-line. E.g., for a flag defined using DEFINE_list, this field may be foo,bar, not ['foo', 'bar']. 4. CURRENT_FLAG_VALUE is produced using str(). This means that the string 'false' will be represented in the same way as the boolean False. Using repr() would have removed this ambiguity and simplified parsing, but would have broken the compatibility with the C++ command-line flags. 5. OPTIONAL_ELEMENTS describe elements relevant for certain kinds of flags: lower_bound, upper_bound (for flags that specify bounds), enum_value (for enum flags), list_separator (for flags that consist of a list of values, separated by a special token). 6. We do not provide any example here: please use --helpxml instead. """ import cgi import getopt import os import re import string import sys import gflags_validators # Are we running at least python 2.2? try: if tuple(sys.version_info[:3]) < (2,2,0): raise NotImplementedError("requires python 2.2.0 or later") except AttributeError: # a very old python, that lacks sys.version_info raise NotImplementedError("requires python 2.2.0 or later") # If we're not running at least python 2.2.1, define True, False, and bool. # Thanks, Guido, for the code. try: True, False, bool except NameError: False = 0 True = 1 def bool(x): if x: return True else: return False # Are we running under pychecker? _RUNNING_PYCHECKER = 'pychecker.python' in sys.modules def _GetCallingModule(): """Returns the name of the module that's calling into this module. We generally use this function to get the name of the module calling a DEFINE_foo... function. """ # Walk down the stack to find the first globals dict that's not ours. for depth in range(1, sys.getrecursionlimit()): if not sys._getframe(depth).f_globals is globals(): globals_for_frame = sys._getframe(depth).f_globals module_name = _GetModuleObjectAndName(globals_for_frame)[1] if module_name is not None: return module_name raise AssertionError("No module was found") def _GetThisModuleObjectAndName(): """Returns: (module object, module name) for this module.""" return _GetModuleObjectAndName(globals()) # module exceptions: class FlagsError(Exception): """The base class for all flags errors.""" pass class DuplicateFlag(FlagsError): """Raised if there is a flag naming conflict.""" pass class DuplicateFlagCannotPropagateNoneToSwig(DuplicateFlag): """Special case of DuplicateFlag -- SWIG flag value can't be set to None. This can be raised when a duplicate flag is created. Even if allow_override is True, we still abort if the new value is None, because it's currently impossible to pass None default value back to SWIG. See FlagValues.SetDefault for details. """ pass # A DuplicateFlagError conveys more information than a # DuplicateFlag. Since there are external modules that create # DuplicateFlags, the interface to DuplicateFlag shouldn't change. class DuplicateFlagError(DuplicateFlag): def __init__(self, flagname, flag_values): self.flagname = flagname message = "The flag '%s' is defined twice." % self.flagname flags_by_module = flag_values.FlagsByModuleDict() for module in flags_by_module: for flag in flags_by_module[module]: if flag.name == flagname or flag.short_name == flagname: message = message + " First from " + module + "," break message = message + " Second from " + _GetCallingModule() DuplicateFlag.__init__(self, message) class IllegalFlagValue(FlagsError): """The flag command line argument is illegal.""" pass class UnrecognizedFlag(FlagsError): """Raised if a flag is unrecognized.""" pass # An UnrecognizedFlagError conveys more information than an UnrecognizedFlag. # Since there are external modules that create DuplicateFlags, the interface to # DuplicateFlag shouldn't change. The flagvalue will be assigned the full value # of the flag and its argument, if any, allowing handling of unrecognzed flags # in an exception handler. # If flagvalue is the empty string, then this exception is an due to a # reference to a flag that was not already defined. class UnrecognizedFlagError(UnrecognizedFlag): def __init__(self, flagname, flagvalue=''): self.flagname = flagname self.flagvalue = flagvalue UnrecognizedFlag.__init__( self, "Unknown command line flag '%s'" % flagname) # Global variable used by expvar _exported_flags = {} _help_width = 80 # width of help output def GetHelpWidth(): """Returns: an integer, the width of help lines that is used in TextWrap.""" return _help_width def CutCommonSpacePrefix(text): """Removes a common space prefix from the lines of a multiline text. If the first line does not start with a space, it is left as it is and only in the remaining lines a common space prefix is being searched for. That means the first line will stay untouched. This is especially useful to turn doc strings into help texts. This is because some people prefer to have the doc comment start already after the apostrophy and then align the following lines while others have the apostrophies on a seperately line. The function also drops trailing empty lines and ignores empty lines following the initial content line while calculating the initial common whitespace. Args: text: text to work on Returns: the resulting text """ text_lines = text.splitlines() # Drop trailing empty lines while text_lines and not text_lines[-1]: text_lines = text_lines[:-1] if text_lines: # We got some content, is the first line starting with a space? if text_lines[0] and text_lines[0][0].isspace(): text_first_line = [] else: text_first_line = [text_lines.pop(0)] # Calculate length of common leading whitesppace (only over content lines) common_prefix = os.path.commonprefix([line for line in text_lines if line]) space_prefix_len = len(common_prefix) - len(common_prefix.lstrip()) # If we have a common space prefix, drop it from all lines if space_prefix_len: for index in xrange(len(text_lines)): if text_lines[index]: text_lines[index] = text_lines[index][space_prefix_len:] return '\n'.join(text_first_line + text_lines) return '' def TextWrap(text, length=None, indent='', firstline_indent=None, tabs=' '): """Wraps a given text to a maximum line length and returns it. We turn lines that only contain whitespaces into empty lines. We keep new lines and tabs (e.g., we do not treat tabs as spaces). Args: text: text to wrap length: maximum length of a line, includes indentation if this is None then use GetHelpWidth() indent: indent for all but first line firstline_indent: indent for first line; if None, fall back to indent tabs: replacement for tabs Returns: wrapped text Raises: FlagsError: if indent not shorter than length FlagsError: if firstline_indent not shorter than length """ # Get defaults where callee used None if length is None: length = GetHelpWidth() if indent is None: indent = '' if len(indent) >= length: raise FlagsError('Indent must be shorter than length') # In line we will be holding the current line which is to be started # with indent (or firstline_indent if available) and then appended # with words. if firstline_indent is None: firstline_indent = '' line = indent else: line = firstline_indent if len(firstline_indent) >= length: raise FlagsError('First iline indent must be shorter than length') # If the callee does not care about tabs we simply convert them to # spaces If callee wanted tabs to be single space then we do that # already here. if not tabs or tabs == ' ': text = text.replace('\t', ' ') else: tabs_are_whitespace = not tabs.strip() line_regex = re.compile('([ ]*)(\t*)([^ \t]+)', re.MULTILINE) # Split the text into lines and the lines with the regex above. The # resulting lines are collected in result[]. For each split we get the # spaces, the tabs and the next non white space (e.g. next word). result = [] for text_line in text.splitlines(): # Store result length so we can find out whether processing the next # line gave any new content old_result_len = len(result) # Process next line with line_regex. For optimization we do an rstrip(). # - process tabs (changes either line or word, see below) # - process word (first try to squeeze on line, then wrap or force wrap) # Spaces found on the line are ignored, they get added while wrapping as # needed. for spaces, current_tabs, word in line_regex.findall(text_line.rstrip()): # If tabs weren't converted to spaces, handle them now if current_tabs: # If the last thing we added was a space anyway then drop # it. But let's not get rid of the indentation. if (((result and line != indent) or (not result and line != firstline_indent)) and line[-1] == ' '): line = line[:-1] # Add the tabs, if that means adding whitespace, just add it at # the line, the rstrip() code while shorten the line down if # necessary if tabs_are_whitespace: line += tabs * len(current_tabs) else: # if not all tab replacement is whitespace we prepend it to the word word = tabs * len(current_tabs) + word # Handle the case where word cannot be squeezed onto current last line if len(line) + len(word) > length and len(indent) + len(word) <= length: result.append(line.rstrip()) line = indent + word word = '' # No space left on line or can we append a space? if len(line) + 1 >= length: result.append(line.rstrip()) line = indent else: line += ' ' # Add word and shorten it up to allowed line length. Restart next # line with indent and repeat, or add a space if we're done (word # finished) This deals with words that caanot fit on one line # (e.g. indent + word longer than allowed line length). while len(line) + len(word) >= length: line += word result.append(line[:length]) word = line[length:] line = indent # Default case, simply append the word and a space if word: line += word + ' ' # End of input line. If we have content we finish the line. If the # current line is just the indent but we had content in during this # original line then we need to add an emoty line. if (result and line != indent) or (not result and line != firstline_indent): result.append(line.rstrip()) elif len(result) == old_result_len: result.append('') line = indent return '\n'.join(result) def DocToHelp(doc): """Takes a __doc__ string and reformats it as help.""" # Get rid of starting and ending white space. Using lstrip() or even # strip() could drop more than maximum of first line and right space # of last line. doc = doc.strip() # Get rid of all empty lines whitespace_only_line = re.compile('^[ \t]+$', re.M) doc = whitespace_only_line.sub('', doc) # Cut out common space at line beginnings doc = CutCommonSpacePrefix(doc) # Just like this module's comment, comments tend to be aligned somehow. # In other words they all start with the same amount of white space # 1) keep double new lines # 2) keep ws after new lines if not empty line # 3) all other new lines shall be changed to a space # Solution: Match new lines between non white space and replace with space. doc = re.sub('(?<=\S)\n(?=\S)', ' ', doc, re.M) return doc def _GetModuleObjectAndName(globals_dict): """Returns the module that defines a global environment, and its name. Args: globals_dict: A dictionary that should correspond to an environment providing the values of the globals. Returns: A pair consisting of (1) module object and (2) module name (a string). Returns (None, None) if the module could not be identified. """ # The use of .items() (instead of .iteritems()) is NOT a mistake: if # a parallel thread imports a module while we iterate over # .iteritems() (not nice, but possible), we get a RuntimeError ... # Hence, we use the slightly slower but safer .items(). for name, module in sys.modules.items(): if getattr(module, '__dict__', None) is globals_dict: if name == '__main__': # Pick a more informative name for the main module. name = sys.argv[0] return (module, name) return (None, None) def _GetMainModule(): """Returns the name of the module from which execution started.""" for depth in range(1, sys.getrecursionlimit()): try: globals_of_main = sys._getframe(depth).f_globals except ValueError: return _GetModuleObjectAndName(globals_of_main)[1] raise AssertionError("No module was found") class FlagValues: """Registry of 'Flag' objects. A 'FlagValues' can then scan command line arguments, passing flag arguments through to the 'Flag' objects that it owns. It also provides easy access to the flag values. Typically only one 'FlagValues' object is needed by an application: gflags.FLAGS This class is heavily overloaded: 'Flag' objects are registered via __setitem__: FLAGS['longname'] = x # register a new flag The .value attribute of the registered 'Flag' objects can be accessed as attributes of this 'FlagValues' object, through __getattr__. Both the long and short name of the original 'Flag' objects can be used to access its value: FLAGS.longname # parsed flag value FLAGS.x # parsed flag value (short name) Command line arguments are scanned and passed to the registered 'Flag' objects through the __call__ method. Unparsed arguments, including argv[0] (e.g. the program name) are returned. argv = FLAGS(sys.argv) # scan command line arguments The original registered Flag objects can be retrieved through the use of the dictionary-like operator, __getitem__: x = FLAGS['longname'] # access the registered Flag object The str() operator of a 'FlagValues' object provides help for all of the registered 'Flag' objects. """ def __init__(self): # Since everything in this class is so heavily overloaded, the only # way of defining and using fields is to access __dict__ directly. # Dictionary: flag name (string) -> Flag object. self.__dict__['__flags'] = {} # Dictionary: module name (string) -> list of Flag objects that are defined # by that module. self.__dict__['__flags_by_module'] = {} # Dictionary: module name (string) -> list of Flag objects that are # key for that module. self.__dict__['__key_flags_by_module'] = {} # Set if we should use new style gnu_getopt rather than getopt when parsing # the args. Only possible with Python 2.3+ self.UseGnuGetOpt(False) def UseGnuGetOpt(self, use_gnu_getopt=True): self.__dict__['__use_gnu_getopt'] = use_gnu_getopt def IsGnuGetOpt(self): return self.__dict__['__use_gnu_getopt'] def FlagDict(self): return self.__dict__['__flags'] def FlagsByModuleDict(self): """Returns the dictionary of module_name -> list of defined flags. Returns: A dictionary. Its keys are module names (strings). Its values are lists of Flag objects. """ return self.__dict__['__flags_by_module'] def KeyFlagsByModuleDict(self): """Returns the dictionary of module_name -> list of key flags. Returns: A dictionary. Its keys are module names (strings). Its values are lists of Flag objects. """ return self.__dict__['__key_flags_by_module'] def _RegisterFlagByModule(self, module_name, flag): """Records the module that defines a specific flag. We keep track of which flag is defined by which module so that we can later sort the flags by module. Args: module_name: A string, the name of a Python module. flag: A Flag object, a flag that is key to the module. """ flags_by_module = self.FlagsByModuleDict() flags_by_module.setdefault(module_name, []).append(flag) def _RegisterKeyFlagForModule(self, module_name, flag): """Specifies that a flag is a key flag for a module. Args: module_name: A string, the name of a Python module. flag: A Flag object, a flag that is key to the module. """ key_flags_by_module = self.KeyFlagsByModuleDict() # The list of key flags for the module named module_name. key_flags = key_flags_by_module.setdefault(module_name, []) # Add flag, but avoid duplicates. if flag not in key_flags: key_flags.append(flag) def _GetFlagsDefinedByModule(self, module): """Returns the list of flags defined by a module. Args: module: A module object or a module name (a string). Returns: A new list of Flag objects. Caller may update this list as he wishes: none of those changes will affect the internals of this FlagValue object. """ if not isinstance(module, str): module = module.__name__ return list(self.FlagsByModuleDict().get(module, [])) def _GetKeyFlagsForModule(self, module): """Returns the list of key flags for a module. Args: module: A module object or a module name (a string) Returns: A new list of Flag objects. Caller may update this list as he wishes: none of those changes will affect the internals of this FlagValue object. """ if not isinstance(module, str): module = module.__name__ # Any flag is a key flag for the module that defined it. NOTE: # key_flags is a fresh list: we can update it without affecting the # internals of this FlagValues object. key_flags = self._GetFlagsDefinedByModule(module) # Take into account flags explicitly declared as key for a module. for flag in self.KeyFlagsByModuleDict().get(module, []): if flag not in key_flags: key_flags.append(flag) return key_flags def AppendFlagValues(self, flag_values): """Appends flags registered in another FlagValues instance. Args: flag_values: registry to copy from """ for flag_name, flag in flag_values.FlagDict().iteritems(): # Each flags with shortname appears here twice (once under its # normal name, and again with its short name). To prevent # problems (DuplicateFlagError) with double flag registration, we # perform a check to make sure that the entry we're looking at is # for its normal name. if flag_name == flag.name: self[flag_name] = flag def RemoveFlagValues(self, flag_values): """Remove flags that were previously appended from another FlagValues. Args: flag_values: registry containing flags to remove. """ for flag_name in flag_values.FlagDict(): self.__delattr__(flag_name) def __setitem__(self, name, flag): """Registers a new flag variable.""" fl = self.FlagDict() if not isinstance(flag, Flag): raise IllegalFlagValue(flag) if not isinstance(name, type("")): raise FlagsError("Flag name must be a string") if len(name) == 0: raise FlagsError("Flag name cannot be empty") # If running under pychecker, duplicate keys are likely to be # defined. Disable check for duplicate keys when pycheck'ing. if (fl.has_key(name) and not flag.allow_override and not fl[name].allow_override and not _RUNNING_PYCHECKER): raise DuplicateFlagError(name, self) short_name = flag.short_name if short_name is not None: if (fl.has_key(short_name) and not flag.allow_override and not fl[short_name].allow_override and not _RUNNING_PYCHECKER): raise DuplicateFlagError(short_name, self) fl[short_name] = flag fl[name] = flag global _exported_flags _exported_flags[name] = flag def __getitem__(self, name): """Retrieves the Flag object for the flag --name.""" return self.FlagDict()[name] def __getattr__(self, name): """Retrieves the 'value' attribute of the flag --name.""" fl = self.FlagDict() if not fl.has_key(name): raise AttributeError(name) return fl[name].value def __setattr__(self, name, value): """Sets the 'value' attribute of the flag --name.""" fl = self.FlagDict() fl[name].value = value self._AssertValidators(fl[name].validators) return value def _AssertAllValidators(self): all_validators = set() for flag in self.FlagDict().itervalues(): for validator in flag.validators: all_validators.add(validator) self._AssertValidators(all_validators) def _AssertValidators(self, validators): """Assert if all validators in the list are satisfied. Asserts validators in the order they were created. Args: validators: Iterable(gflags_validators.Validator), validators to be verified Raises: AttributeError: if validators work with a non-existing flag. IllegalFlagValue: if validation fails for at least one validator """ for validator in sorted( validators, key=lambda validator: validator.insertion_index): try: validator.Verify(self) except gflags_validators.Error, e: message = validator.PrintFlagsWithValues(self) raise IllegalFlagValue('%s: %s' % (message, str(e))) def _FlagIsRegistered(self, flag_obj): """Checks whether a Flag object is registered under some name. Note: this is non trivial: in addition to its normal name, a flag may have a short name too. In self.FlagDict(), both the normal and the short name are mapped to the same flag object. E.g., calling only "del FLAGS.short_name" is not unregistering the corresponding Flag object (it is still registered under the longer name). Args: flag_obj: A Flag object. Returns: A boolean: True iff flag_obj is registered under some name. """ flag_dict = self.FlagDict() # Check whether flag_obj is registered under its long name. name = flag_obj.name if flag_dict.get(name, None) == flag_obj: return True # Check whether flag_obj is registered under its short name. short_name = flag_obj.short_name if (short_name is not None and flag_dict.get(short_name, None) == flag_obj): return True # The flag cannot be registered under any other name, so we do not # need to do a full search through the values of self.FlagDict(). return False def __delattr__(self, flag_name): """Deletes a previously-defined flag from a flag object. This method makes sure we can delete a flag by using del flag_values_object.<flag_name> E.g., flags.DEFINE_integer('foo', 1, 'Integer flag.') del flags.FLAGS.foo Args: flag_name: A string, the name of the flag to be deleted. Raises: AttributeError: When there is no registered flag named flag_name. """ fl = self.FlagDict() if flag_name not in fl: raise AttributeError(flag_name) flag_obj = fl[flag_name] del fl[flag_name] if not self._FlagIsRegistered(flag_obj): # If the Flag object indicated by flag_name is no longer # registered (please see the docstring of _FlagIsRegistered), then # we delete the occurences of the flag object in all our internal # dictionaries. self.__RemoveFlagFromDictByModule(self.FlagsByModuleDict(), flag_obj) self.__RemoveFlagFromDictByModule(self.KeyFlagsByModuleDict(), flag_obj) def __RemoveFlagFromDictByModule(self, flags_by_module_dict, flag_obj): """Removes a flag object from a module -> list of flags dictionary. Args: flags_by_module_dict: A dictionary that maps module names to lists of flags. flag_obj: A flag object. """ for unused_module, flags_in_module in flags_by_module_dict.iteritems(): # while (as opposed to if) takes care of multiple occurences of a # flag in the list for the same module. while flag_obj in flags_in_module: flags_in_module.remove(flag_obj) def SetDefault(self, name, value): """Changes the default value of the named flag object.""" fl = self.FlagDict() if not fl.has_key(name): raise AttributeError(name) fl[name].SetDefault(value) self._AssertValidators(fl[name].validators) def __contains__(self, name): """Returns True if name is a value (flag) in the dict.""" return name in self.FlagDict() has_key = __contains__ # a synonym for __contains__() def __iter__(self): return self.FlagDict().iterkeys() def __call__(self, argv): """Parses flags from argv; stores parsed flags into this FlagValues object. All unparsed arguments are returned. Flags are parsed using the GNU Program Argument Syntax Conventions, using getopt: http://www.gnu.org/software/libc/manual/html_mono/libc.html#Getopt Args: argv: argument list. Can be of any type that may be converted to a list. Returns: The list of arguments not parsed as options, including argv[0] Raises: FlagsError: on any parsing error """ # Support any sequence type that can be converted to a list argv = list(argv) shortopts = "" longopts = [] fl = self.FlagDict() # This pre parses the argv list for --flagfile=<> options. argv = argv[:1] + self.ReadFlagsFromFiles(argv[1:], force_gnu=False) # Correct the argv to support the google style of passing boolean # parameters. Boolean parameters may be passed by using --mybool, # --nomybool, --mybool=(true|false|1|0). getopt does not support # having options that may or may not have a parameter. We replace # instances of the short form --mybool and --nomybool with their # full forms: --mybool=(true|false). original_argv = list(argv) # list() makes a copy shortest_matches = None for name, flag in fl.items(): if not flag.boolean: continue if shortest_matches is None: # Determine the smallest allowable prefix for all flag names shortest_matches = self.ShortestUniquePrefixes(fl) no_name = 'no' + name prefix = shortest_matches[name] no_prefix = shortest_matches[no_name] # Replace all occurences of this boolean with extended forms for arg_idx in range(1, len(argv)): arg = argv[arg_idx] if arg.find('=') >= 0: continue if arg.startswith('--'+prefix) and ('--'+name).startswith(arg): argv[arg_idx] = ('--%s=true' % name) elif arg.startswith('--'+no_prefix) and ('--'+no_name).startswith(arg): argv[arg_idx] = ('--%s=false' % name) # Loop over all of the flags, building up the lists of short options # and long options that will be passed to getopt. Short options are # specified as a string of letters, each letter followed by a colon # if it takes an argument. Long options are stored in an array of # strings. Each string ends with an '=' if it takes an argument. for name, flag in fl.items(): longopts.append(name + "=") if len(name) == 1: # one-letter option: allow short flag type also shortopts += name if not flag.boolean: shortopts += ":" longopts.append('undefok=') undefok_flags = [] # In case --undefok is specified, loop to pick up unrecognized # options one by one. unrecognized_opts = [] args = argv[1:] while True: try: if self.__dict__['__use_gnu_getopt']: optlist, unparsed_args = getopt.gnu_getopt(args, shortopts, longopts) else: optlist, unparsed_args = getopt.getopt(args, shortopts, longopts) break except getopt.GetoptError, e: if not e.opt or e.opt in fl: # Not an unrecognized option, reraise the exception as a FlagsError raise FlagsError(e) # Remove offender from args and try again for arg_index in range(len(args)): if ((args[arg_index] == '--' + e.opt) or (args[arg_index] == '-' + e.opt) or (args[arg_index].startswith('--' + e.opt + '='))): unrecognized_opts.append((e.opt, args[arg_index])) args = args[0:arg_index] + args[arg_index+1:] break else: # We should have found the option, so we don't expect to get # here. We could assert, but raising the original exception # might work better. raise FlagsError(e) for name, arg in optlist: if name == '--undefok': flag_names = arg.split(',') undefok_flags.extend(flag_names) # For boolean flags, if --undefok=boolflag is specified, then we should # also accept --noboolflag, in addition to --boolflag. # Since we don't know the type of the undefok'd flag, this will affect # non-boolean flags as well. # NOTE: You shouldn't use --undefok=noboolflag, because then we will # accept --nonoboolflag here. We are choosing not to do the conversion # from noboolflag -> boolflag because of the ambiguity that flag names # can start with 'no'. undefok_flags.extend('no' + name for name in flag_names) continue if name.startswith('--'): # long option name = name[2:] short_option = 0 else: # short option name = name[1:] short_option = 1 if fl.has_key(name): flag = fl[name] if flag.boolean and short_option: arg = 1 flag.Parse(arg) # If there were unrecognized options, raise an exception unless # the options were named via --undefok. for opt, value in unrecognized_opts: if opt not in undefok_flags: raise UnrecognizedFlagError(opt, value) if unparsed_args: if self.__dict__['__use_gnu_getopt']: # if using gnu_getopt just return the program name + remainder of argv. ret_val = argv[:1] + unparsed_args else: # unparsed_args becomes the first non-flag detected by getopt to # the end of argv. Because argv may have been modified above, # return original_argv for this region. ret_val = argv[:1] + original_argv[-len(unparsed_args):] else: ret_val = argv[:1] self._AssertAllValidators() return ret_val def Reset(self): """Resets the values to the point before FLAGS(argv) was called.""" for f in self.FlagDict().values(): f.Unparse() def RegisteredFlags(self): """Returns: a list of the names and short names of all registered flags.""" return self.FlagDict().keys() def FlagValuesDict(self): """Returns: a dictionary that maps flag names to flag values.""" flag_values = {} for flag_name in self.RegisteredFlags(): flag = self.FlagDict()[flag_name] flag_values[flag_name] = flag.value return flag_values def __str__(self): """Generates a help string for all known flags.""" return self.GetHelp() def GetHelp(self, prefix=''): """Generates a help string for all known flags.""" helplist = [] flags_by_module = self.FlagsByModuleDict() if flags_by_module: modules = flags_by_module.keys() modules.sort() # Print the help for the main module first, if possible. main_module = _GetMainModule() if main_module in modules: modules.remove(main_module) modules = [main_module] + modules for module in modules: self.__RenderOurModuleFlags(module, helplist) self.__RenderModuleFlags('gflags', _SPECIAL_FLAGS.FlagDict().values(), helplist) else: # Just print one long list of flags. self.__RenderFlagList( self.FlagDict().values() + _SPECIAL_FLAGS.FlagDict().values(), helplist, prefix) return '\n'.join(helplist) def __RenderModuleFlags(self, module, flags, output_lines, prefix=""): """Generates a help string for a given module.""" if not isinstance(module, str): module = module.__name__ output_lines.append('\n%s%s:' % (prefix, module)) self.__RenderFlagList(flags, output_lines, prefix + " ") def __RenderOurModuleFlags(self, module, output_lines, prefix=""): """Generates a help string for a given module.""" flags = self._GetFlagsDefinedByModule(module) if flags: self.__RenderModuleFlags(module, flags, output_lines, prefix) def __RenderOurModuleKeyFlags(self, module, output_lines, prefix=""): """Generates a help string for the key flags of a given module. Args: module: A module object or a module name (a string). output_lines: A list of strings. The generated help message lines will be appended to this list. prefix: A string that is prepended to each generated help line. """ key_flags = self._GetKeyFlagsForModule(module) if key_flags: self.__RenderModuleFlags(module, key_flags, output_lines, prefix) def ModuleHelp(self, module): """Describe the key flags of a module. Args: module: A module object or a module name (a string). Returns: string describing the key flags of a module. """ helplist = [] self.__RenderOurModuleKeyFlags(module, helplist) return '\n'.join(helplist) def MainModuleHelp(self): """Describe the key flags of the main module. Returns: string describing the key flags of a module. """ return self.ModuleHelp(_GetMainModule()) def __RenderFlagList(self, flaglist, output_lines, prefix=" "): fl = self.FlagDict() special_fl = _SPECIAL_FLAGS.FlagDict() flaglist = [(flag.name, flag) for flag in flaglist] flaglist.sort() flagset = {} for (name, flag) in flaglist: # It's possible this flag got deleted or overridden since being # registered in the per-module flaglist. Check now against the # canonical source of current flag information, the FlagDict. if fl.get(name, None) != flag and special_fl.get(name, None) != flag: # a different flag is using this name now continue # only print help once if flagset.has_key(flag): continue flagset[flag] = 1 flaghelp = "" if flag.short_name: flaghelp += "-%s," % flag.short_name if flag.boolean: flaghelp += "--[no]%s" % flag.name + ":" else: flaghelp += "--%s" % flag.name + ":" flaghelp += " " if flag.help: flaghelp += flag.help flaghelp = TextWrap(flaghelp, indent=prefix+" ", firstline_indent=prefix) if flag.default_as_str: flaghelp += "\n" flaghelp += TextWrap("(default: %s)" % flag.default_as_str, indent=prefix+" ") if flag.parser.syntactic_help: flaghelp += "\n" flaghelp += TextWrap("(%s)" % flag.parser.syntactic_help, indent=prefix+" ") output_lines.append(flaghelp) def get(self, name, default): """Returns the value of a flag (if not None) or a default value. Args: name: A string, the name of a flag. default: Default value to use if the flag value is None. """ value = self.__getattr__(name) if value is not None: # Can't do if not value, b/c value might be '0' or "" return value else: return default def ShortestUniquePrefixes(self, fl): """Returns: dictionary; maps flag names to their shortest unique prefix.""" # Sort the list of flag names sorted_flags = [] for name, flag in fl.items(): sorted_flags.append(name) if flag.boolean: sorted_flags.append('no%s' % name) sorted_flags.sort() # For each name in the sorted list, determine the shortest unique # prefix by comparing itself to the next name and to the previous # name (the latter check uses cached info from the previous loop). shortest_matches = {} prev_idx = 0 for flag_idx in range(len(sorted_flags)): curr = sorted_flags[flag_idx] if flag_idx == (len(sorted_flags) - 1): next = None else: next = sorted_flags[flag_idx+1] next_len = len(next) for curr_idx in range(len(curr)): if (next is None or curr_idx >= next_len or curr[curr_idx] != next[curr_idx]): # curr longer than next or no more chars in common shortest_matches[curr] = curr[:max(prev_idx, curr_idx) + 1] prev_idx = curr_idx break else: # curr shorter than (or equal to) next shortest_matches[curr] = curr prev_idx = curr_idx + 1 # next will need at least one more char return shortest_matches def __IsFlagFileDirective(self, flag_string): """Checks whether flag_string contain a --flagfile=<foo> directive.""" if isinstance(flag_string, type("")): if flag_string.startswith('--flagfile='): return 1 elif flag_string == '--flagfile': return 1 elif flag_string.startswith('-flagfile='): return 1 elif flag_string == '-flagfile': return 1 else: return 0 return 0 def ExtractFilename(self, flagfile_str): """Returns filename from a flagfile_str of form -[-]flagfile=filename. The cases of --flagfile foo and -flagfile foo shouldn't be hitting this function, as they are dealt with in the level above this function. """ if flagfile_str.startswith('--flagfile='): return os.path.expanduser((flagfile_str[(len('--flagfile=')):]).strip()) elif flagfile_str.startswith('-flagfile='): return os.path.expanduser((flagfile_str[(len('-flagfile=')):]).strip()) else: raise FlagsError('Hit illegal --flagfile type: %s' % flagfile_str) def __GetFlagFileLines(self, filename, parsed_file_list): """Returns the useful (!=comments, etc) lines from a file with flags. Args: filename: A string, the name of the flag file. parsed_file_list: A list of the names of the files we have already read. MUTATED BY THIS FUNCTION. Returns: List of strings. See the note below. NOTE(springer): This function checks for a nested --flagfile=<foo> tag and handles the lower file recursively. It returns a list of all the lines that _could_ contain command flags. This is EVERYTHING except whitespace lines and comments (lines starting with '#' or '//'). """ line_list = [] # All line from flagfile. flag_line_list = [] # Subset of lines w/o comments, blanks, flagfile= tags. try: file_obj = open(filename, 'r') except IOError, e_msg: print e_msg print 'ERROR:: Unable to open flagfile: %s' % (filename) return flag_line_list line_list = file_obj.readlines() file_obj.close() parsed_file_list.append(filename) # This is where we check each line in the file we just read. for line in line_list: if line.isspace(): pass # Checks for comment (a line that starts with '#'). elif line.startswith('#') or line.startswith('//'): pass # Checks for a nested "--flagfile=<bar>" flag in the current file. # If we find one, recursively parse down into that file. elif self.__IsFlagFileDirective(line): sub_filename = self.ExtractFilename(line) # We do a little safety check for reparsing a file we've already done. if not sub_filename in parsed_file_list: included_flags = self.__GetFlagFileLines(sub_filename, parsed_file_list) flag_line_list.extend(included_flags) else: # Case of hitting a circularly included file. print >>sys.stderr, ('Warning: Hit circular flagfile dependency: %s' % sub_filename) else: # Any line that's not a comment or a nested flagfile should get # copied into 2nd position. This leaves earlier arguements # further back in the list, thus giving them higher priority. flag_line_list.append(line.strip()) return flag_line_list def ReadFlagsFromFiles(self, argv, force_gnu=True): """Processes command line args, but also allow args to be read from file. Args: argv: A list of strings, usually sys.argv[1:], which may contain one or more flagfile directives of the form --flagfile="./filename". Note that the name of the program (sys.argv[0]) should be omitted. force_gnu: If False, --flagfile parsing obeys normal flag semantics. If True, --flagfile parsing instead follows gnu_getopt semantics. *** WARNING *** force_gnu=False may become the future default! Returns: A new list which has the original list combined with what we read from any flagfile(s). References: Global gflags.FLAG class instance. This function should be called before the normal FLAGS(argv) call. This function scans the input list for a flag that looks like: --flagfile=<somefile>. Then it opens <somefile>, reads all valid key and value pairs and inserts them into the input list between the first item of the list and any subsequent items in the list. Note that your application's flags are still defined the usual way using gflags DEFINE_flag() type functions. Notes (assuming we're getting a commandline of some sort as our input): --> Flags from the command line argv _should_ always take precedence! --> A further "--flagfile=<otherfile.cfg>" CAN be nested in a flagfile. It will be processed after the parent flag file is done. --> For duplicate flags, first one we hit should "win". --> In a flagfile, a line beginning with # or // is a comment. --> Entirely blank lines _should_ be ignored. """ parsed_file_list = [] rest_of_args = argv new_argv = [] while rest_of_args: current_arg = rest_of_args[0] rest_of_args = rest_of_args[1:] if self.__IsFlagFileDirective(current_arg): # This handles the case of -(-)flagfile foo. In this case the # next arg really is part of this one. if current_arg == '--flagfile' or current_arg == '-flagfile': if not rest_of_args: raise IllegalFlagValue('--flagfile with no argument') flag_filename = os.path.expanduser(rest_of_args[0]) rest_of_args = rest_of_args[1:] else: # This handles the case of (-)-flagfile=foo. flag_filename = self.ExtractFilename(current_arg) new_argv[0:0] = self.__GetFlagFileLines(flag_filename, parsed_file_list) else: new_argv.append(current_arg) # Stop parsing after '--', like getopt and gnu_getopt. if current_arg == '--': break # Stop parsing after a non-flag, like getopt. if not current_arg.startswith('-'): if not force_gnu and not self.__dict__['__use_gnu_getopt']: break if rest_of_args: new_argv.extend(rest_of_args) return new_argv def FlagsIntoString(self): """Returns a string with the flags assignments from this FlagValues object. This function ignores flags whose value is None. Each flag assignment is separated by a newline. NOTE: MUST mirror the behavior of the C++ function CommandlineFlagsIntoString from google3/base/commandlineflags.cc. """ s = '' for flag in self.FlagDict().values(): if flag.value is not None: s += flag.Serialize() + '\n' return s def AppendFlagsIntoFile(self, filename): """Appends all flags assignments from this FlagInfo object to a file. Output will be in the format of a flagfile. NOTE: MUST mirror the behavior of the C++ version of AppendFlagsIntoFile from google3/base/commandlineflags.cc. """ out_file = open(filename, 'a') out_file.write(self.FlagsIntoString()) out_file.close() def WriteHelpInXMLFormat(self, outfile=None): """Outputs flag documentation in XML format. NOTE: We use element names that are consistent with those used by the C++ command-line flag library, from google3/base/commandlineflags_reporting.cc. We also use a few new elements (e.g., <key>), but we do not interfere / overlap with existing XML elements used by the C++ library. Please maintain this consistency. Args: outfile: File object we write to. Default None means sys.stdout. """ outfile = outfile or sys.stdout outfile.write('<?xml version=\"1.0\"?>\n') outfile.write('<AllFlags>\n') indent = ' ' _WriteSimpleXMLElement(outfile, 'program', os.path.basename(sys.argv[0]), indent) usage_doc = sys.modules['__main__'].__doc__ if not usage_doc: usage_doc = '\nUSAGE: %s [flags]\n' % sys.argv[0] else: usage_doc = usage_doc.replace('%s', sys.argv[0]) _WriteSimpleXMLElement(outfile, 'usage', usage_doc, indent) # Get list of key flags for the main module. key_flags = self._GetKeyFlagsForModule(_GetMainModule()) # Sort flags by declaring module name and next by flag name. flags_by_module = self.FlagsByModuleDict() all_module_names = list(flags_by_module.keys()) all_module_names.sort() for module_name in all_module_names: flag_list = [(f.name, f) for f in flags_by_module[module_name]] flag_list.sort() for unused_flag_name, flag in flag_list: is_key = flag in key_flags flag.WriteInfoInXMLFormat(outfile, module_name, is_key=is_key, indent=indent) outfile.write('</AllFlags>\n') outfile.flush() def AddValidator(self, validator): """Register new flags validator to be checked. Args: validator: gflags_validators.Validator Raises: AttributeError: if validators work with a non-existing flag. """ for flag_name in validator.GetFlagsNames(): flag = self.FlagDict()[flag_name] flag.validators.append(validator) # end of FlagValues definition # The global FlagValues instance FLAGS = FlagValues() def _MakeXMLSafe(s): """Escapes <, >, and & from s, and removes XML 1.0-illegal chars.""" s = cgi.escape(s) # Escape <, >, and & # Remove characters that cannot appear in an XML 1.0 document # (http://www.w3.org/TR/REC-xml/#charsets). # # NOTE: if there are problems with current solution, one may move to # XML 1.1, which allows such chars, if they're entity-escaped (&#xHH;). s = re.sub(r'[\x00-\x08\x0b\x0c\x0e-\x1f]', '', s) return s def _WriteSimpleXMLElement(outfile, name, value, indent): """Writes a simple XML element. Args: outfile: File object we write the XML element to. name: A string, the name of XML element. value: A Python object, whose string representation will be used as the value of the XML element. indent: A string, prepended to each line of generated output. """ value_str = str(value) if isinstance(value, bool): # Display boolean values as the C++ flag library does: no caps. value_str = value_str.lower() outfile.write('%s<%s>%s</%s>\n' % (indent, name, _MakeXMLSafe(value_str), name)) class Flag: """Information about a command-line flag. 'Flag' objects define the following fields: .name - the name for this flag .default - the default value for this flag .default_as_str - default value as repr'd string, e.g., "'true'" (or None) .value - the most recent parsed value of this flag; set by Parse() .help - a help string or None if no help is available .short_name - the single letter alias for this flag (or None) .boolean - if 'true', this flag does not accept arguments .present - true if this flag was parsed from command line flags. .parser - an ArgumentParser object .serializer - an ArgumentSerializer object .allow_override - the flag may be redefined without raising an error The only public method of a 'Flag' object is Parse(), but it is typically only called by a 'FlagValues' object. The Parse() method is a thin wrapper around the 'ArgumentParser' Parse() method. The parsed value is saved in .value, and the .present attribute is updated. If this flag was already present, a FlagsError is raised. Parse() is also called during __init__ to parse the default value and initialize the .value attribute. This enables other python modules to safely use flags even if the __main__ module neglects to parse the command line arguments. The .present attribute is cleared after __init__ parsing. If the default value is set to None, then the __init__ parsing step is skipped and the .value attribute is initialized to None. Note: The default value is also presented to the user in the help string, so it is important that it be a legal value for this flag. """ def __init__(self, parser, serializer, name, default, help_string, short_name=None, boolean=0, allow_override=0): self.name = name if not help_string: help_string = '(no help available)' self.help = help_string self.short_name = short_name self.boolean = boolean self.present = 0 self.parser = parser self.serializer = serializer self.allow_override = allow_override self.value = None self.validators = [] self.SetDefault(default) def __GetParsedValueAsString(self, value): if value is None: return None if self.serializer: return repr(self.serializer.Serialize(value)) if self.boolean: if value: return repr('true') else: return repr('false') return repr(str(value)) def Parse(self, argument): try: self.value = self.parser.Parse(argument) except ValueError, e: # recast ValueError as IllegalFlagValue raise IllegalFlagValue("flag --%s=%s: %s" % (self.name, argument, e)) self.present += 1 def Unparse(self): if self.default is None: self.value = None else: self.Parse(self.default) self.present = 0 def Serialize(self): if self.value is None: return '' if self.boolean: if self.value: return "--%s" % self.name else: return "--no%s" % self.name else: if not self.serializer: raise FlagsError("Serializer not present for flag %s" % self.name) return "--%s=%s" % (self.name, self.serializer.Serialize(self.value)) def SetDefault(self, value): """Changes the default value (and current value too) for this Flag.""" # We can't allow a None override because it may end up not being # passed to C++ code when we're overriding C++ flags. So we # cowardly bail out until someone fixes the semantics of trying to # pass None to a C++ flag. See swig_flags.Init() for details on # this behavior. # TODO(olexiy): Users can directly call this method, bypassing all flags # validators (we don't have FlagValues here, so we can not check # validators). # The simplest solution I see is to make this method private. # Another approach would be to store reference to the corresponding # FlagValues with each flag, but this seems to be an overkill. if value is None and self.allow_override: raise DuplicateFlagCannotPropagateNoneToSwig(self.name) self.default = value self.Unparse() self.default_as_str = self.__GetParsedValueAsString(self.value) def Type(self): """Returns: a string that describes the type of this Flag.""" # NOTE: we use strings, and not the types.*Type constants because # our flags can have more exotic types, e.g., 'comma separated list # of strings', 'whitespace separated list of strings', etc. return self.parser.Type() def WriteInfoInXMLFormat(self, outfile, module_name, is_key=False, indent=''): """Writes common info about this flag, in XML format. This is information that is relevant to all flags (e.g., name, meaning, etc.). If you defined a flag that has some other pieces of info, then please override _WriteCustomInfoInXMLFormat. Please do NOT override this method. Args: outfile: File object we write to. module_name: A string, the name of the module that defines this flag. is_key: A boolean, True iff this flag is key for main module. indent: A string that is prepended to each generated line. """ outfile.write(indent + '<flag>\n') inner_indent = indent + ' ' if is_key: _WriteSimpleXMLElement(outfile, 'key', 'yes', inner_indent) _WriteSimpleXMLElement(outfile, 'file', module_name, inner_indent) # Print flag features that are relevant for all flags. _WriteSimpleXMLElement(outfile, 'name', self.name, inner_indent) if self.short_name: _WriteSimpleXMLElement(outfile, 'short_name', self.short_name, inner_indent) if self.help: _WriteSimpleXMLElement(outfile, 'meaning', self.help, inner_indent) # The default flag value can either be represented as a string like on the # command line, or as a Python object. We serialize this value in the # latter case in order to remain consistent. if self.serializer and not isinstance(self.default, str): default_serialized = self.serializer.Serialize(self.default) else: default_serialized = self.default _WriteSimpleXMLElement(outfile, 'default', default_serialized, inner_indent) _WriteSimpleXMLElement(outfile, 'current', self.value, inner_indent) _WriteSimpleXMLElement(outfile, 'type', self.Type(), inner_indent) # Print extra flag features this flag may have. self._WriteCustomInfoInXMLFormat(outfile, inner_indent) outfile.write(indent + '</flag>\n') def _WriteCustomInfoInXMLFormat(self, outfile, indent): """Writes extra info about this flag, in XML format. "Extra" means "not already printed by WriteInfoInXMLFormat above." Args: outfile: File object we write to. indent: A string that is prepended to each generated line. """ # Usually, the parser knows the extra details about the flag, so # we just forward the call to it. self.parser.WriteCustomInfoInXMLFormat(outfile, indent) # End of Flag definition class _ArgumentParserCache(type): """Metaclass used to cache and share argument parsers among flags.""" _instances = {} def __call__(mcs, *args, **kwargs): """Returns an instance of the argument parser cls. This method overrides behavior of the __new__ methods in all subclasses of ArgumentParser (inclusive). If an instance for mcs with the same set of arguments exists, this instance is returned, otherwise a new instance is created. If any keyword arguments are defined, or the values in args are not hashable, this method always returns a new instance of cls. Args: args: Positional initializer arguments. kwargs: Initializer keyword arguments. Returns: An instance of cls, shared or new. """ if kwargs: return type.__call__(mcs, *args, **kwargs) else: instances = mcs._instances key = (mcs,) + tuple(args) try: return instances[key] except KeyError: # No cache entry for key exists, create a new one. return instances.setdefault(key, type.__call__(mcs, *args)) except TypeError: # An object in args cannot be hashed, always return # a new instance. return type.__call__(mcs, *args) class ArgumentParser(object): """Base class used to parse and convert arguments. The Parse() method checks to make sure that the string argument is a legal value and convert it to a native type. If the value cannot be converted, it should throw a 'ValueError' exception with a human readable explanation of why the value is illegal. Subclasses should also define a syntactic_help string which may be presented to the user to describe the form of the legal values. Argument parser classes must be stateless, since instances are cached and shared between flags. Initializer arguments are allowed, but all member variables must be derived from initializer arguments only. """ __metaclass__ = _ArgumentParserCache syntactic_help = "" def Parse(self, argument): """Default implementation: always returns its argument unmodified.""" return argument def Type(self): return 'string' def WriteCustomInfoInXMLFormat(self, outfile, indent): pass class ArgumentSerializer: """Base class for generating string representations of a flag value.""" def Serialize(self, value): return str(value) class ListSerializer(ArgumentSerializer): def __init__(self, list_sep): self.list_sep = list_sep def Serialize(self, value): return self.list_sep.join([str(x) for x in value]) # Flags validators def RegisterValidator(flag_name, checker, message='Flag validation failed', flag_values=FLAGS): """Adds a constraint, which will be enforced during program execution. The constraint is validated when flags are initially parsed, and after each change of the corresponding flag's value. Args: flag_name: string, name of the flag to be checked. checker: method to validate the flag. input - value of the corresponding flag (string, boolean, etc. This value will be passed to checker by the library). See file's docstring for examples. output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise gflags_validators.Error(desired_error_message). message: error text to be shown to the user if checker returns False. If checker raises gflags_validators.Error, message from the raised Error will be shown. flag_values: FlagValues Raises: AttributeError: if flag_name is not registered as a valid flag name. """ flag_values.AddValidator(gflags_validators.SimpleValidator(flag_name, checker, message)) def MarkFlagAsRequired(flag_name, flag_values=FLAGS): """Ensure that flag is not None during program execution. Registers a flag validator, which will follow usual validator rules. Args: flag_name: string, name of the flag flag_values: FlagValues Raises: AttributeError: if flag_name is not registered as a valid flag name. """ RegisterValidator(flag_name, lambda value: value is not None, message='Flag --%s must be specified.' % flag_name, flag_values=flag_values) def _RegisterBoundsValidatorIfNeeded(parser, name, flag_values): """Enforce lower and upper bounds for numeric flags. Args: parser: NumericParser (either FloatParser or IntegerParser). Provides lower and upper bounds, and help text to display. name: string, name of the flag flag_values: FlagValues """ if parser.lower_bound is not None or parser.upper_bound is not None: def Checker(value): if value is not None and parser.IsOutsideBounds(value): message = '%s is not %s' % (value, parser.syntactic_help) raise gflags_validators.Error(message) return True RegisterValidator(name, Checker, flag_values=flag_values) # The DEFINE functions are explained in mode details in the module doc string. def DEFINE(parser, name, default, help, flag_values=FLAGS, serializer=None, **args): """Registers a generic Flag object. NOTE: in the docstrings of all DEFINE* functions, "registers" is short for "creates a new flag and registers it". Auxiliary function: clients should use the specialized DEFINE_<type> function instead. Args: parser: ArgumentParser that is used to parse the flag arguments. name: A string, the flag name. default: The default value of the flag. help: A help string. flag_values: FlagValues object the flag will be registered with. serializer: ArgumentSerializer that serializes the flag value. args: Dictionary with extra keyword args that are passes to the Flag __init__. """ DEFINE_flag(Flag(parser, serializer, name, default, help, **args), flag_values) def DEFINE_flag(flag, flag_values=FLAGS): """Registers a 'Flag' object with a 'FlagValues' object. By default, the global FLAGS 'FlagValue' object is used. Typical users will use one of the more specialized DEFINE_xxx functions, such as DEFINE_string or DEFINE_integer. But developers who need to create Flag objects themselves should use this function to register their flags. """ # copying the reference to flag_values prevents pychecker warnings fv = flag_values fv[flag.name] = flag # Tell flag_values who's defining the flag. if isinstance(flag_values, FlagValues): # Regarding the above isinstance test: some users pass funny # values of flag_values (e.g., {}) in order to avoid the flag # registration (in the past, there used to be a flag_values == # FLAGS test here) and redefine flags with the same name (e.g., # debug). To avoid breaking their code, we perform the # registration only if flag_values is a real FlagValues object. flag_values._RegisterFlagByModule(_GetCallingModule(), flag) def _InternalDeclareKeyFlags(flag_names, flag_values=FLAGS, key_flag_values=None): """Declares a flag as key for the calling module. Internal function. User code should call DECLARE_key_flag or ADOPT_module_key_flags instead. Args: flag_names: A list of strings that are names of already-registered Flag objects. flag_values: A FlagValues object that the flags listed in flag_names have registered with (the value of the flag_values argument from the DEFINE_* calls that defined those flags). This should almost never need to be overridden. key_flag_values: A FlagValues object that (among possibly many other things) keeps track of the key flags for each module. Default None means "same as flag_values". This should almost never need to be overridden. Raises: UnrecognizedFlagError: when we refer to a flag that was not defined yet. """ key_flag_values = key_flag_values or flag_values module = _GetCallingModule() for flag_name in flag_names: if flag_name not in flag_values: raise UnrecognizedFlagError(flag_name) flag = flag_values.FlagDict()[flag_name] key_flag_values._RegisterKeyFlagForModule(module, flag) def DECLARE_key_flag(flag_name, flag_values=FLAGS): """Declares one flag as key to the current module. Key flags are flags that are deemed really important for a module. They are important when listing help messages; e.g., if the --helpshort command-line flag is used, then only the key flags of the main module are listed (instead of all flags, as in the case of --help). Sample usage: flags.DECLARED_key_flag('flag_1') Args: flag_name: A string, the name of an already declared flag. (Redeclaring flags as key, including flags implicitly key because they were declared in this module, is a no-op.) flag_values: A FlagValues object. This should almost never need to be overridden. """ if flag_name in _SPECIAL_FLAGS: # Take care of the special flags, e.g., --flagfile, --undefok. # These flags are defined in _SPECIAL_FLAGS, and are treated # specially during flag parsing, taking precedence over the # user-defined flags. _InternalDeclareKeyFlags([flag_name], flag_values=_SPECIAL_FLAGS, key_flag_values=flag_values) return _InternalDeclareKeyFlags([flag_name], flag_values=flag_values) def ADOPT_module_key_flags(module, flag_values=FLAGS): """Declares that all flags key to a module are key to the current module. Args: module: A module object. flag_values: A FlagValues object. This should almost never need to be overridden. Raises: FlagsError: When given an argument that is a module name (a string), instead of a module object. """ # NOTE(salcianu): an even better test would be if not # isinstance(module, types.ModuleType) but I didn't want to import # types for such a tiny use. if isinstance(module, str): raise FlagsError('Received module name %s; expected a module object.' % module) _InternalDeclareKeyFlags( [f.name for f in flag_values._GetKeyFlagsForModule(module.__name__)], flag_values=flag_values) # If module is this flag module, take _SPECIAL_FLAGS into account. if module == _GetThisModuleObjectAndName()[0]: _InternalDeclareKeyFlags( # As we associate flags with _GetCallingModule(), the special # flags defined in this module are incorrectly registered with # a different module. So, we can't use _GetKeyFlagsForModule. # Instead, we take all flags from _SPECIAL_FLAGS (a private # FlagValues, where no other module should register flags). [f.name for f in _SPECIAL_FLAGS.FlagDict().values()], flag_values=_SPECIAL_FLAGS, key_flag_values=flag_values) # # STRING FLAGS # def DEFINE_string(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value can be any string.""" parser = ArgumentParser() serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) # # BOOLEAN FLAGS # # and the special HELP flags. class BooleanParser(ArgumentParser): """Parser of boolean values.""" def Convert(self, argument): """Converts the argument to a boolean; raise ValueError on errors.""" if type(argument) == str: if argument.lower() in ['true', 't', '1']: return True elif argument.lower() in ['false', 'f', '0']: return False bool_argument = bool(argument) if argument == bool_argument: # The argument is a valid boolean (True, False, 0, or 1), and not just # something that always converts to bool (list, string, int, etc.). return bool_argument raise ValueError('Non-boolean argument to boolean flag', argument) def Parse(self, argument): val = self.Convert(argument) return val def Type(self): return 'bool' class BooleanFlag(Flag): """Basic boolean flag. Boolean flags do not take any arguments, and their value is either True (1) or False (0). The false value is specified on the command line by prepending the word 'no' to either the long or the short flag name. For example, if a Boolean flag was created whose long name was 'update' and whose short name was 'x', then this flag could be explicitly unset through either --noupdate or --nox. """ def __init__(self, name, default, help, short_name=None, **args): p = BooleanParser() Flag.__init__(self, p, None, name, default, help, short_name, 1, **args) if not self.help: self.help = "a boolean value" def DEFINE_boolean(name, default, help, flag_values=FLAGS, **args): """Registers a boolean flag. Such a boolean flag does not take an argument. If a user wants to specify a false value explicitly, the long option beginning with 'no' must be used: i.e. --noflag This flag will have a value of None, True or False. None is possible if default=None and the user does not specify the flag on the command line. """ DEFINE_flag(BooleanFlag(name, default, help, **args), flag_values) # Match C++ API to unconfuse C++ people. DEFINE_bool = DEFINE_boolean class HelpFlag(BooleanFlag): """ HelpFlag is a special boolean flag that prints usage information and raises a SystemExit exception if it is ever found in the command line arguments. Note this is called with allow_override=1, so other apps can define their own --help flag, replacing this one, if they want. """ def __init__(self): BooleanFlag.__init__(self, "help", 0, "show this help", short_name="?", allow_override=1) def Parse(self, arg): if arg: doc = sys.modules["__main__"].__doc__ flags = str(FLAGS) print doc or ("\nUSAGE: %s [flags]\n" % sys.argv[0]) if flags: print "flags:" print flags sys.exit(1) class HelpXMLFlag(BooleanFlag): """Similar to HelpFlag, but generates output in XML format.""" def __init__(self): BooleanFlag.__init__(self, 'helpxml', False, 'like --help, but generates XML output', allow_override=1) def Parse(self, arg): if arg: FLAGS.WriteHelpInXMLFormat(sys.stdout) sys.exit(1) class HelpshortFlag(BooleanFlag): """ HelpshortFlag is a special boolean flag that prints usage information for the "main" module, and rasies a SystemExit exception if it is ever found in the command line arguments. Note this is called with allow_override=1, so other apps can define their own --helpshort flag, replacing this one, if they want. """ def __init__(self): BooleanFlag.__init__(self, "helpshort", 0, "show usage only for this module", allow_override=1) def Parse(self, arg): if arg: doc = sys.modules["__main__"].__doc__ flags = FLAGS.MainModuleHelp() print doc or ("\nUSAGE: %s [flags]\n" % sys.argv[0]) if flags: print "flags:" print flags sys.exit(1) # # Numeric parser - base class for Integer and Float parsers # class NumericParser(ArgumentParser): """Parser of numeric values. Parsed value may be bounded to a given upper and lower bound. """ def IsOutsideBounds(self, val): return ((self.lower_bound is not None and val < self.lower_bound) or (self.upper_bound is not None and val > self.upper_bound)) def Parse(self, argument): val = self.Convert(argument) if self.IsOutsideBounds(val): raise ValueError("%s is not %s" % (val, self.syntactic_help)) return val def WriteCustomInfoInXMLFormat(self, outfile, indent): if self.lower_bound is not None: _WriteSimpleXMLElement(outfile, 'lower_bound', self.lower_bound, indent) if self.upper_bound is not None: _WriteSimpleXMLElement(outfile, 'upper_bound', self.upper_bound, indent) def Convert(self, argument): """Default implementation: always returns its argument unmodified.""" return argument # End of Numeric Parser # # FLOAT FLAGS # class FloatParser(NumericParser): """Parser of floating point values. Parsed value may be bounded to a given upper and lower bound. """ number_article = "a" number_name = "number" syntactic_help = " ".join((number_article, number_name)) def __init__(self, lower_bound=None, upper_bound=None): super(FloatParser, self).__init__() self.lower_bound = lower_bound self.upper_bound = upper_bound sh = self.syntactic_help if lower_bound is not None and upper_bound is not None: sh = ("%s in the range [%s, %s]" % (sh, lower_bound, upper_bound)) elif lower_bound == 0: sh = "a non-negative %s" % self.number_name elif upper_bound == 0: sh = "a non-positive %s" % self.number_name elif upper_bound is not None: sh = "%s <= %s" % (self.number_name, upper_bound) elif lower_bound is not None: sh = "%s >= %s" % (self.number_name, lower_bound) self.syntactic_help = sh def Convert(self, argument): """Converts argument to a float; raises ValueError on errors.""" return float(argument) def Type(self): return 'float' # End of FloatParser def DEFINE_float(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value must be a float. If lower_bound or upper_bound are set, then this flag must be within the given range. """ parser = FloatParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) _RegisterBoundsValidatorIfNeeded(parser, name, flag_values=flag_values) # # INTEGER FLAGS # class IntegerParser(NumericParser): """Parser of an integer value. Parsed value may be bounded to a given upper and lower bound. """ number_article = "an" number_name = "integer" syntactic_help = " ".join((number_article, number_name)) def __init__(self, lower_bound=None, upper_bound=None): super(IntegerParser, self).__init__() self.lower_bound = lower_bound self.upper_bound = upper_bound sh = self.syntactic_help if lower_bound is not None and upper_bound is not None: sh = ("%s in the range [%s, %s]" % (sh, lower_bound, upper_bound)) elif lower_bound == 1: sh = "a positive %s" % self.number_name elif upper_bound == -1: sh = "a negative %s" % self.number_name elif lower_bound == 0: sh = "a non-negative %s" % self.number_name elif upper_bound == 0: sh = "a non-positive %s" % self.number_name elif upper_bound is not None: sh = "%s <= %s" % (self.number_name, upper_bound) elif lower_bound is not None: sh = "%s >= %s" % (self.number_name, lower_bound) self.syntactic_help = sh def Convert(self, argument): __pychecker__ = 'no-returnvalues' if type(argument) == str: base = 10 if len(argument) > 2 and argument[0] == "0" and argument[1] == "x": base = 16 try: return int(argument, base) # ValueError is thrown when argument is a string, and overflows an int. except ValueError: return long(argument, base) else: try: return int(argument) # OverflowError is thrown when argument is numeric, and overflows an int. except OverflowError: return long(argument) def Type(self): return 'int' def DEFINE_integer(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value must be an integer. If lower_bound, or upper_bound are set, then this flag must be within the given range. """ parser = IntegerParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) _RegisterBoundsValidatorIfNeeded(parser, name, flag_values=flag_values) # # ENUM FLAGS # class EnumParser(ArgumentParser): """Parser of a string enum value (a string value from a given set). If enum_values (see below) is not specified, any string is allowed. """ def __init__(self, enum_values=None): super(EnumParser, self).__init__() self.enum_values = enum_values def Parse(self, argument): if self.enum_values and argument not in self.enum_values: raise ValueError("value should be one of <%s>" % "|".join(self.enum_values)) return argument def Type(self): return 'string enum' class EnumFlag(Flag): """Basic enum flag; its value can be any string from list of enum_values.""" def __init__(self, name, default, help, enum_values=None, short_name=None, **args): enum_values = enum_values or [] p = EnumParser(enum_values) g = ArgumentSerializer() Flag.__init__(self, p, g, name, default, help, short_name, **args) if not self.help: self.help = "an enum string" self.help = "<%s>: %s" % ("|".join(enum_values), self.help) def _WriteCustomInfoInXMLFormat(self, outfile, indent): for enum_value in self.parser.enum_values: _WriteSimpleXMLElement(outfile, 'enum_value', enum_value, indent) def DEFINE_enum(name, default, enum_values, help, flag_values=FLAGS, **args): """Registers a flag whose value can be any string from enum_values.""" DEFINE_flag(EnumFlag(name, default, help, enum_values, ** args), flag_values) # # LIST FLAGS # class BaseListParser(ArgumentParser): """Base class for a parser of lists of strings. To extend, inherit from this class; from the subclass __init__, call BaseListParser.__init__(self, token, name) where token is a character used to tokenize, and name is a description of the separator. """ def __init__(self, token=None, name=None): assert name super(BaseListParser, self).__init__() self._token = token self._name = name self.syntactic_help = "a %s separated list" % self._name def Parse(self, argument): if isinstance(argument, list): return argument elif argument == '': return [] else: return [s.strip() for s in argument.split(self._token)] def Type(self): return '%s separated list of strings' % self._name class ListParser(BaseListParser): """Parser for a comma-separated list of strings.""" def __init__(self): BaseListParser.__init__(self, ',', 'comma') def WriteCustomInfoInXMLFormat(self, outfile, indent): BaseListParser.WriteCustomInfoInXMLFormat(self, outfile, indent) _WriteSimpleXMLElement(outfile, 'list_separator', repr(','), indent) class WhitespaceSeparatedListParser(BaseListParser): """Parser for a whitespace-separated list of strings.""" def __init__(self): BaseListParser.__init__(self, None, 'whitespace') def WriteCustomInfoInXMLFormat(self, outfile, indent): BaseListParser.WriteCustomInfoInXMLFormat(self, outfile, indent) separators = list(string.whitespace) separators.sort() for ws_char in string.whitespace: _WriteSimpleXMLElement(outfile, 'list_separator', repr(ws_char), indent) def DEFINE_list(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value is a comma-separated list of strings.""" parser = ListParser() serializer = ListSerializer(',') DEFINE(parser, name, default, help, flag_values, serializer, **args) def DEFINE_spaceseplist(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value is a whitespace-separated list of strings. Any whitespace can be used as a separator. """ parser = WhitespaceSeparatedListParser() serializer = ListSerializer(' ') DEFINE(parser, name, default, help, flag_values, serializer, **args) # # MULTI FLAGS # class MultiFlag(Flag): """A flag that can appear multiple time on the command-line. The value of such a flag is a list that contains the individual values from all the appearances of that flag on the command-line. See the __doc__ for Flag for most behavior of this class. Only differences in behavior are described here: * The default value may be either a single value or a list of values. A single value is interpreted as the [value] singleton list. * The value of the flag is always a list, even if the option was only supplied once, and even if the default value is a single value """ def __init__(self, *args, **kwargs): Flag.__init__(self, *args, **kwargs) self.help += ';\n repeat this option to specify a list of values' def Parse(self, arguments): """Parses one or more arguments with the installed parser. Args: arguments: a single argument or a list of arguments (typically a list of default values); a single argument is converted internally into a list containing one item. """ if not isinstance(arguments, list): # Default value may be a list of values. Most other arguments # will not be, so convert them into a single-item list to make # processing simpler below. arguments = [arguments] if self.present: # keep a backup reference to list of previously supplied option values values = self.value else: # "erase" the defaults with an empty list values = [] for item in arguments: # have Flag superclass parse argument, overwriting self.value reference Flag.Parse(self, item) # also increments self.present values.append(self.value) # put list of option values back in the 'value' attribute self.value = values def Serialize(self): if not self.serializer: raise FlagsError("Serializer not present for flag %s" % self.name) if self.value is None: return '' s = '' multi_value = self.value for self.value in multi_value: if s: s += ' ' s += Flag.Serialize(self) self.value = multi_value return s def Type(self): return 'multi ' + self.parser.Type() def DEFINE_multi(parser, serializer, name, default, help, flag_values=FLAGS, **args): """Registers a generic MultiFlag that parses its args with a given parser. Auxiliary function. Normal users should NOT use it directly. Developers who need to create their own 'Parser' classes for options which can appear multiple times can call this module function to register their flags. """ DEFINE_flag(MultiFlag(parser, serializer, name, default, help, **args), flag_values) def DEFINE_multistring(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value can be a list of any strings. Use the flag on the command line multiple times to place multiple string values into the list. The 'default' may be a single string (which will be converted into a single-element list) or a list of strings. """ parser = ArgumentParser() serializer = ArgumentSerializer() DEFINE_multi(parser, serializer, name, default, help, flag_values, **args) def DEFINE_multi_int(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value can be a list of arbitrary integers. Use the flag on the command line multiple times to place multiple integer values into the list. The 'default' may be a single integer (which will be converted into a single-element list) or a list of integers. """ parser = IntegerParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE_multi(parser, serializer, name, default, help, flag_values, **args) # Now register the flags that we want to exist in all applications. # These are all defined with allow_override=1, so user-apps can use # these flagnames for their own purposes, if they want. DEFINE_flag(HelpFlag()) DEFINE_flag(HelpshortFlag()) DEFINE_flag(HelpXMLFlag()) # Define special flags here so that help may be generated for them. # NOTE: Please do NOT use _SPECIAL_FLAGS from outside this module. _SPECIAL_FLAGS = FlagValues() DEFINE_string( 'flagfile', "", "Insert flag definitions from the given file into the command line.", _SPECIAL_FLAGS) DEFINE_string( 'undefok', "", "comma-separated list of flag names that it is okay to specify " "on the command line even if the program does not define a flag " "with that name. IMPORTANT: flags in this list that have " "arguments MUST use the --flag=value format.", _SPECIAL_FLAGS)
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Query with ranked results against the shopping search API""" from apiclient.discovery import build SHOPPING_API_VERSION = 'v1' DEVELOPER_KEY = 'AIzaSyACZJW4JwcWwz5taR2gjIMNQrtgDLfILPc' def main(): """Get and print a histogram of the top 15 brand distribution for a search query. Histograms are created by using the "Facets" functionality of the API. A Facet is a view of a certain property of products, containing a number of buckets, one for each value of that property. Or concretely, for a parameter such as "brand" of a product, the facets would include a facet for brand, which would contain a number of buckets, one for each brand returned in the result. A bucket contains either a value and a count, or a value and a range. In the simple case of a value and a count for our example of the "brand" property, the value would be the brand name, eg "sony" and the count would be the number of results in the search. """ client = build('shopping', SHOPPING_API_VERSION, developerKey=DEVELOPER_KEY) resource = client.products() request = resource.list(source='public', country='US', q=u'digital camera', facets_include='brand:15', facets_enabled=True) response = request.execute() # Pick the first and only facet for this query facet = response['facets'][0] print '\n\tHistogram for "%s":\n' % facet['property'] labels = [] values = [] for bucket in facet['buckets']: labels.append(bucket['value'].rjust(20)) values.append(bucket['count']) weighting = 50.0 / max(values) for label, value in zip(labels, values): print label, '#' * int(weighting * value), '(%s)' % value print if __name__ == '__main__': main()
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. '''Simple command-line example for The Google Search API for Shopping. Command-line application that does a search for products. ''' __author__ = 'aherrman@google.com (Andy Herrman)' from apiclient.discovery import build # Uncomment the next line to get very detailed logging # httplib2.debuglevel = 4 def main(): p = build('shopping', 'v1', developerKey='AIzaSyDRRpR3GS1F1_jKNNM9HCNd2wJQyPG3oN0') # Search over all public offers: print 'Searching all public offers.' res = p.products().list( country='US', source='public', q='android t-shirt' ).execute() print_items(res['items']) # Search over a specific merchant's offers: print print 'Searching Google Store.' res = p.products().list( country='US', source='public', q='android t-shirt', restrictBy='accountId:5968952', ).execute() print_items(res['items']) # Remember the Google Id of the last product googleId = res['items'][0]['product']['googleId'] # Get data for the single public offer: print print 'Getting data for offer %s' % googleId res = p.products().get( source='public', accountId='5968952', productIdType='gid', productId=googleId ).execute() print_item(res) def print_item(item): """Displays a single item: title, merchant, link.""" product = item['product'] print '- %s [%s] (%s)' % (product['title'], product['author']['name'], product['link']) def print_items(items): """Displays a number of items.""" for item in items: print_item(item) if __name__ == '__main__': main()
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Full text search query against the shopping search API""" import pprint from apiclient.discovery import build SHOPPING_API_VERSION = 'v1' DEVELOPER_KEY = 'AIzaSyACZJW4JwcWwz5taR2gjIMNQrtgDLfILPc' def main(): """Get and print a feed of all public products matching the search query "digital camera". This is achieved by using the q query parameter to the list method. The "|" operator can be used to search for alternative search terms, for example: q = 'banana|apple' will search for bananas or apples. Search phrases such as those containing spaces can be specified by surrounding them with double quotes, for example q='"mp3 player"'. This can be useful when combining with the "|" operator such as q = '"mp3 player"|ipod'. """ client = build('shopping', SHOPPING_API_VERSION, developerKey=DEVELOPER_KEY) resource = client.products() # Note the 'q' parameter, which will contain the value of the search query request = resource.list(source='public', country='US', q=u'digital camera') response = request.execute() pprint.pprint(response) if __name__ == '__main__': main()
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Basic query against the public shopping search API""" import pprint from apiclient.discovery import build SHOPPING_API_VERSION = 'v1' DEVELOPER_KEY = 'AIzaSyACZJW4JwcWwz5taR2gjIMNQrtgDLfILPc' def main(): """Get and print a feed of all public products available in the United States. Note: The source and country arguments are required to pass to the list method. """ client = build('shopping', SHOPPING_API_VERSION, developerKey=DEVELOPER_KEY) resource = client.products() request = resource.list(source='public', country='US') response = request.execute() pprint.pprint(response) if __name__ == '__main__': main()
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Query that is restricted by a parameter against the public shopping search API""" import pprint from apiclient.discovery import build SHOPPING_API_VERSION = 'v1' DEVELOPER_KEY = 'AIzaSyACZJW4JwcWwz5taR2gjIMNQrtgDLfILPc' def main(): """Get and print a feed of all public products matching the search query "digital camera", that are created by "Canon" available in the United States. The "restrictBy" parameter controls which types of results are returned. Multiple values for a single restrictBy can be separated by the "|" operator, so to look for all products created by Canon, Sony, or Apple: restrictBy = 'brand:canon|sony|apple' Multiple restricting parameters should be separated by a comma, so for products created by Sony with the word "32GB" in the title: restrictBy = 'brand:sony,title:32GB' """ client = build('shopping', SHOPPING_API_VERSION, developerKey=DEVELOPER_KEY) resource = client.products() request = resource.list(source='public', country='US', restrictBy='brand:canon', q='Digital Camera') response = request.execute() pprint.pprint(response) if __name__ == '__main__': main()
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Query with ranked results against the shopping search API""" from apiclient.discovery import build SHOPPING_API_VERSION = 'v1' DEVELOPER_KEY = 'AIzaSyACZJW4JwcWwz5taR2gjIMNQrtgDLfILPc' def main(): """Get and print a histogram of the top 15 brand distribution for a search query. Histograms are created by using the "Facets" functionality of the API. A Facet is a view of a certain property of products, containing a number of buckets, one for each value of that property. Or concretely, for a parameter such as "brand" of a product, the facets would include a facet for brand, which would contain a number of buckets, one for each brand returned in the result. A bucket contains either a value and a count, or a value and a range. In the simple case of a value and a count for our example of the "brand" property, the value would be the brand name, eg "sony" and the count would be the number of results in the search. """ client = build('shopping', SHOPPING_API_VERSION, developerKey=DEVELOPER_KEY) resource = client.products() request = resource.list(source='public', country='US', q=u'digital camera', facets_include='brand:15', facets_enabled=True) response = request.execute() # Pick the first and only facet for this query facet = response['facets'][0] print '\n\tHistogram for "%s":\n' % facet['property'] labels = [] values = [] for bucket in facet['buckets']: labels.append(bucket['value'].rjust(20)) values.append(bucket['count']) weighting = 50.0 / max(values) for label, value in zip(labels, values): print label, '#' * int(weighting * value), '(%s)' % value print if __name__ == '__main__': main()
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Query with grouping against the shopping search API""" import pprint from apiclient.discovery import build SHOPPING_API_VERSION = 'v1' DEVELOPER_KEY = 'AIzaSyACZJW4JwcWwz5taR2gjIMNQrtgDLfILPc' def main(): """Get and print a feed of public products in the United States mathing a text search query for 'digital camera' and grouped by the 8 top brands. The list method of the resource should be called with the "crowdBy" parameter. Each parameter should be designed as <attribute>:<occurence>, where <occurrence> is the number of that <attribute> that will be used. For example, to crowd by the 5 top brands, the parameter would be "brand:5". The possible rules for crowding are currently: account_id:<occurrence> (eg account_id:5) brand:<occurrence> (eg brand:5) condition:<occurrence> (eg condition:3) gtin:<occurrence> (eg gtin:10) price:<occurrence> (eg price:10) Multiple crowding rules should be specified by separating them with a comma, for example to crowd by the top 5 brands and then condition of those items, the parameter should be crowdBy="brand:5,condition:3" """ client = build('shopping', SHOPPING_API_VERSION, developerKey=DEVELOPER_KEY) resource = client.products() # The crowdBy parameter to the list method causes the results to be grouped, # in this case by the top 8 brands. request = resource.list(source='public', country='US', q=u'digital camera', crowdBy='brand:8') response = request.execute() pprint.pprint(response) if __name__ == '__main__': main()
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Queries with paginated results against the shopping search API""" import pprint from apiclient.discovery import build SHOPPING_API_VERSION = 'v1' DEVELOPER_KEY = 'AIzaSyACZJW4JwcWwz5taR2gjIMNQrtgDLfILPc' def main(): """Get and print a the entire paginated feed of public products in the United States. Pagination is controlled with the "startIndex" parameter passed to the list method of the resource. """ client = build('shopping', SHOPPING_API_VERSION, developerKey=DEVELOPER_KEY) resource = client.products() # The first request contains the information we need for the total items, and # page size, as well as returning the first page of results. request = resource.list(source='public', country='US', q=u'digital camera') response = request.execute() itemsPerPage = response['itemsPerPage'] totalItems = response['totalItems'] for i in range(1, totalItems, itemsPerPage): answer = raw_input('About to display results from %s to %s, y/(n)? ' % (i, i + itemsPerPage)) if answer.strip().lower().startswith('n'): # Stop if the user has had enough break else: # Fetch this series of results request = resource.list(source='public', country='US', q=u'digital camera', startIndex=i) response = request.execute() pprint.pprint(response) if __name__ == '__main__': main()
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Full text search query against the shopping search API""" import pprint from apiclient.discovery import build SHOPPING_API_VERSION = 'v1' DEVELOPER_KEY = 'AIzaSyACZJW4JwcWwz5taR2gjIMNQrtgDLfILPc' def main(): """Get and print a feed of all public products matching the search query "digital camera". This is achieved by using the q query parameter to the list method. The "|" operator can be used to search for alternative search terms, for example: q = 'banana|apple' will search for bananas or apples. Search phrases such as those containing spaces can be specified by surrounding them with double quotes, for example q='"mp3 player"'. This can be useful when combining with the "|" operator such as q = '"mp3 player"|ipod'. """ client = build('shopping', SHOPPING_API_VERSION, developerKey=DEVELOPER_KEY) resource = client.products() # Note the 'q' parameter, which will contain the value of the search query request = resource.list(source='public', country='US', q=u'digital camera') response = request.execute() pprint.pprint(response) if __name__ == '__main__': main()
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. '''Simple command-line example for The Google Search API for Shopping. Command-line application that does a search for products. ''' __author__ = 'aherrman@google.com (Andy Herrman)' from apiclient.discovery import build # Uncomment the next line to get very detailed logging # httplib2.debuglevel = 4 def main(): p = build('shopping', 'v1', developerKey='AIzaSyDRRpR3GS1F1_jKNNM9HCNd2wJQyPG3oN0') # Search over all public offers: print 'Searching all public offers.' res = p.products().list( country='US', source='public', q='android t-shirt' ).execute() print_items(res['items']) # Search over a specific merchant's offers: print print 'Searching Google Store.' res = p.products().list( country='US', source='public', q='android t-shirt', restrictBy='accountId:5968952', ).execute() print_items(res['items']) # Remember the Google Id of the last product googleId = res['items'][0]['product']['googleId'] # Get data for the single public offer: print print 'Getting data for offer %s' % googleId res = p.products().get( source='public', accountId='5968952', productIdType='gid', productId=googleId ).execute() print_item(res) def print_item(item): """Displays a single item: title, merchant, link.""" product = item['product'] print '- %s [%s] (%s)' % (product['title'], product['author']['name'], product['link']) def print_items(items): """Displays a number of items.""" for item in items: print_item(item) if __name__ == '__main__': main()
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Query with ranked results against the shopping search API""" import pprint from apiclient.discovery import build SHOPPING_API_VERSION = 'v1' DEVELOPER_KEY = 'AIzaSyACZJW4JwcWwz5taR2gjIMNQrtgDLfILPc' def main(): """Get and print a feed of public products in the United States mathing a text search query for 'digital camera' ranked by ascending price. The list method for the resource should be called with the "rankBy" parameter. 5 parameters to rankBy are currently supported by the API. They are: "relevancy" "modificationTime:ascending" "modificationTime:descending" "price:ascending" "price:descending" These parameters can be combined The default ranking is "relevancy" if the rankBy parameter is omitted. """ client = build('shopping', SHOPPING_API_VERSION, developerKey=DEVELOPER_KEY) resource = client.products() # The rankBy parameter to the list method causes results to be ranked, in # this case by ascending price. request = resource.list(source='public', country='US', q=u'digital camera', rankBy='price:ascending') response = request.execute() pprint.pprint(response) if __name__ == '__main__': main()
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Basic query against the public shopping search API""" import pprint from apiclient.discovery import build SHOPPING_API_VERSION = 'v1' DEVELOPER_KEY = 'AIzaSyACZJW4JwcWwz5taR2gjIMNQrtgDLfILPc' def main(): """Get and print a feed of all public products available in the United States. Note: The source and country arguments are required to pass to the list method. """ client = build('shopping', SHOPPING_API_VERSION, developerKey=DEVELOPER_KEY) resource = client.products() request = resource.list(source='public', country='US') response = request.execute() pprint.pprint(response) if __name__ == '__main__': main()
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Query that is restricted by a parameter against the public shopping search API""" import pprint from apiclient.discovery import build SHOPPING_API_VERSION = 'v1' DEVELOPER_KEY = 'AIzaSyACZJW4JwcWwz5taR2gjIMNQrtgDLfILPc' def main(): """Get and print a feed of all public products matching the search query "digital camera", that are created by "Canon" available in the United States. The "restrictBy" parameter controls which types of results are returned. Multiple values for a single restrictBy can be separated by the "|" operator, so to look for all products created by Canon, Sony, or Apple: restrictBy = 'brand:canon|sony|apple' Multiple restricting parameters should be separated by a comma, so for products created by Sony with the word "32GB" in the title: restrictBy = 'brand:sony,title:32GB' """ client = build('shopping', SHOPPING_API_VERSION, developerKey=DEVELOPER_KEY) resource = client.products() request = resource.list(source='public', country='US', restrictBy='brand:canon', q='Digital Camera') response = request.execute() pprint.pprint(response) if __name__ == '__main__': main()
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Queries with paginated results against the shopping search API""" import pprint from apiclient.discovery import build SHOPPING_API_VERSION = 'v1' DEVELOPER_KEY = 'AIzaSyACZJW4JwcWwz5taR2gjIMNQrtgDLfILPc' def main(): """Get and print a the entire paginated feed of public products in the United States. Pagination is controlled with the "startIndex" parameter passed to the list method of the resource. """ client = build('shopping', SHOPPING_API_VERSION, developerKey=DEVELOPER_KEY) resource = client.products() # The first request contains the information we need for the total items, and # page size, as well as returning the first page of results. request = resource.list(source='public', country='US', q=u'digital camera') response = request.execute() itemsPerPage = response['itemsPerPage'] totalItems = response['totalItems'] for i in range(1, totalItems, itemsPerPage): answer = raw_input('About to display results from %s to %s, y/(n)? ' % (i, i + itemsPerPage)) if answer.strip().lower().startswith('n'): # Stop if the user has had enough break else: # Fetch this series of results request = resource.list(source='public', country='US', q=u'digital camera', startIndex=i) response = request.execute() pprint.pprint(response) if __name__ == '__main__': main()
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Query with grouping against the shopping search API""" import pprint from apiclient.discovery import build SHOPPING_API_VERSION = 'v1' DEVELOPER_KEY = 'AIzaSyACZJW4JwcWwz5taR2gjIMNQrtgDLfILPc' def main(): """Get and print a feed of public products in the United States mathing a text search query for 'digital camera' and grouped by the 8 top brands. The list method of the resource should be called with the "crowdBy" parameter. Each parameter should be designed as <attribute>:<occurence>, where <occurrence> is the number of that <attribute> that will be used. For example, to crowd by the 5 top brands, the parameter would be "brand:5". The possible rules for crowding are currently: account_id:<occurrence> (eg account_id:5) brand:<occurrence> (eg brand:5) condition:<occurrence> (eg condition:3) gtin:<occurrence> (eg gtin:10) price:<occurrence> (eg price:10) Multiple crowding rules should be specified by separating them with a comma, for example to crowd by the top 5 brands and then condition of those items, the parameter should be crowdBy="brand:5,condition:3" """ client = build('shopping', SHOPPING_API_VERSION, developerKey=DEVELOPER_KEY) resource = client.products() # The crowdBy parameter to the list method causes the results to be grouped, # in this case by the top 8 brands. request = resource.list(source='public', country='US', q=u'digital camera', crowdBy='brand:8') response = request.execute() pprint.pprint(response) if __name__ == '__main__': main()
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Query with ranked results against the shopping search API""" import pprint from apiclient.discovery import build SHOPPING_API_VERSION = 'v1' DEVELOPER_KEY = 'AIzaSyACZJW4JwcWwz5taR2gjIMNQrtgDLfILPc' def main(): """Get and print a feed of public products in the United States mathing a text search query for 'digital camera' ranked by ascending price. The list method for the resource should be called with the "rankBy" parameter. 5 parameters to rankBy are currently supported by the API. They are: "relevancy" "modificationTime:ascending" "modificationTime:descending" "price:ascending" "price:descending" These parameters can be combined The default ranking is "relevancy" if the rankBy parameter is omitted. """ client = build('shopping', SHOPPING_API_VERSION, developerKey=DEVELOPER_KEY) resource = client.products() # The rankBy parameter to the list method causes results to be ranked, in # this case by ascending price. request = resource.list(source='public', country='US', q=u'digital camera', rankBy='price:ascending') response = request.execute() pprint.pprint(response) if __name__ == '__main__': main()
Python
#!/usr/bin/env python # # Copyright 2007 Google Inc. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. # __author__ = 'jcgregorio@google.com (Joe Gregorio)' import httplib2 import inspect import os import pydoc import re from apiclient.discovery import build from apiclient.anyjson import simplejson from google.appengine.api import memcache from google.appengine.ext import webapp from google.appengine.ext.webapp import template from google.appengine.ext.webapp import util class MainHandler(webapp.RequestHandler): def get(self): http = httplib2.Http(memcache) resp, content = http.request('https://www.googleapis.com/discovery/v0.3/directory?preferred=true') directory = simplejson.loads(content)['items'] path = os.path.join(os.path.dirname(__file__), 'index.html') self.response.out.write( template.render( path, {'directory': directory, })) def render(resource): obj, name = pydoc.resolve(type(resource)) return pydoc.html.page( pydoc.describe(obj), pydoc.html.document(obj, name)) class ResourceHandler(webapp.RequestHandler): def get(self, service_name, version, collection): resource = build(service_name, version) # descend the object path if collection: path = collection.split('/') if path: for method in path: resource = getattr(resource, method)() page = render(resource) collections = [] for name in dir(resource): if not "_" in name and callable(getattr(resource, name)) and hasattr( getattr(resource, name), '__is_resource__'): collections.append(name) if collection is None: collection_path = '' else: collection_path = collection + '/' for name in collections: page = re.sub('strong>(%s)<' % name, r'strong><a href="/%s/%s/%s">\1</a><' % ( service_name, version, collection_path + name), page) # TODO(jcgregorio) breadcrumbs # TODO(jcgregorio) sample code? page = re.sub('<p>', r'<a href="/">Home</a><p>', page, 1) self.response.out.write(page) def main(): application = webapp.WSGIApplication( [ (r'/', MainHandler), (r'/([^\/]*)/([^\/]*)(?:/(.*))?', ResourceHandler), ], debug=True) util.run_wsgi_app(application) if __name__ == '__main__': main()
Python
#!/usr/bin/env python # Copyright (c) 2010, Google Inc. # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. """Module to enforce different constraints on flags. A validator represents an invariant, enforced over a one or more flags. See 'FLAGS VALIDATORS' in flags.py's docstring for a usage manual. """ __author__ = 'olexiy@google.com (Olexiy Oryeshko)' class Error(Exception): """Thrown If validator constraint is not satisfied.""" class Validator(object): """Base class for flags validators. Users should NOT overload these classes, and use flags.Register... methods instead. """ # Used to assign each validator an unique insertion_index validators_count = 0 def __init__(self, checker, message): """Constructor to create all validators. Args: checker: function to verify the constraint. Input of this method varies, see SimpleValidator and DictionaryValidator for a detailed description. message: string, error message to be shown to the user """ self.checker = checker self.message = message Validator.validators_count += 1 # Used to assert validators in the order they were registered (CL/18694236) self.insertion_index = Validator.validators_count def Verify(self, flag_values): """Verify that constraint is satisfied. flags library calls this method to verify Validator's constraint. Args: flag_values: flags.FlagValues, containing all flags Raises: Error: if constraint is not satisfied. """ param = self._GetInputToCheckerFunction(flag_values) if not self.checker(param): raise Error(self.message) def GetFlagsNames(self): """Return the names of the flags checked by this validator. Returns: [string], names of the flags """ raise NotImplementedError('This method should be overloaded') def PrintFlagsWithValues(self, flag_values): raise NotImplementedError('This method should be overloaded') def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues, containing all flags. Returns: Return type depends on the specific validator. """ raise NotImplementedError('This method should be overloaded') class SimpleValidator(Validator): """Validator behind RegisterValidator() method. Validates that a single flag passes its checker function. The checker function takes the flag value and returns True (if value looks fine) or, if flag value is not valid, either returns False or raises an Exception.""" def __init__(self, flag_name, checker, message): """Constructor. Args: flag_name: string, name of the flag. checker: function to verify the validator. input - value of the corresponding flag (string, boolean, etc). output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise Error. message: string, error message to be shown to the user if validator's condition is not satisfied """ super(SimpleValidator, self).__init__(checker, message) self.flag_name = flag_name def GetFlagsNames(self): return [self.flag_name] def PrintFlagsWithValues(self, flag_values): return 'flag --%s=%s' % (self.flag_name, flag_values[self.flag_name].value) def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues Returns: value of the corresponding flag. """ return flag_values[self.flag_name].value class DictionaryValidator(Validator): """Validator behind RegisterDictionaryValidator method. Validates that flag values pass their common checker function. The checker function takes flag values and returns True (if values look fine) or, if values are not valid, either returns False or raises an Exception. """ def __init__(self, flag_names, checker, message): """Constructor. Args: flag_names: [string], containing names of the flags used by checker. checker: function to verify the validator. input - dictionary, with keys() being flag_names, and value for each key being the value of the corresponding flag (string, boolean, etc). output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise Error. message: string, error message to be shown to the user if validator's condition is not satisfied """ super(DictionaryValidator, self).__init__(checker, message) self.flag_names = flag_names def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues Returns: dictionary, with keys() being self.lag_names, and value for each key being the value of the corresponding flag (string, boolean, etc). """ return dict([key, flag_values[key].value] for key in self.flag_names) def PrintFlagsWithValues(self, flag_values): prefix = 'flags ' flags_with_values = [] for key in self.flag_names: flags_with_values.append('%s=%s' % (key, flag_values[key].value)) return prefix + ', '.join(flags_with_values) def GetFlagsNames(self): return self.flag_names
Python
#!/usr/bin/env python # # Copyright 2007 Google Inc. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. # __author__ = 'jcgregorio@google.com (Joe Gregorio)' import httplib2 import inspect import os import pydoc import re from apiclient.discovery import build from apiclient.anyjson import simplejson from google.appengine.api import memcache from google.appengine.ext import webapp from google.appengine.ext.webapp import template from google.appengine.ext.webapp import util class MainHandler(webapp.RequestHandler): def get(self): http = httplib2.Http(memcache) resp, content = http.request('https://www.googleapis.com/discovery/v0.3/directory?preferred=true') directory = simplejson.loads(content)['items'] path = os.path.join(os.path.dirname(__file__), 'index.html') self.response.out.write( template.render( path, {'directory': directory, })) def render(resource): obj, name = pydoc.resolve(type(resource)) return pydoc.html.page( pydoc.describe(obj), pydoc.html.document(obj, name)) class ResourceHandler(webapp.RequestHandler): def get(self, service_name, version, collection): resource = build(service_name, version) # descend the object path if collection: path = collection.split('/') if path: for method in path: resource = getattr(resource, method)() page = render(resource) collections = [] for name in dir(resource): if not "_" in name and callable(getattr(resource, name)) and hasattr( getattr(resource, name), '__is_resource__'): collections.append(name) if collection is None: collection_path = '' else: collection_path = collection + '/' for name in collections: page = re.sub('strong>(%s)<' % name, r'strong><a href="/%s/%s/%s">\1</a><' % ( service_name, version, collection_path + name), page) # TODO(jcgregorio) breadcrumbs # TODO(jcgregorio) sample code? page = re.sub('<p>', r'<a href="/">Home</a><p>', page, 1) self.response.out.write(page) def main(): application = webapp.WSGIApplication( [ (r'/', MainHandler), (r'/([^\/]*)/([^\/]*)(?:/(.*))?', ResourceHandler), ], debug=True) util.run_wsgi_app(application) if __name__ == '__main__': main()
Python
#!/usr/bin/env python # Copyright (c) 2007, Google Inc. # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. # # --- # Author: Chad Lester # Design and style contributions by: # Amit Patel, Bogdan Cocosel, Daniel Dulitz, Eric Tiedemann, # Eric Veach, Laurence Gonsalves, Matthew Springer # Code reorganized a bit by Craig Silverstein """This module is used to define and parse command line flags. This module defines a *distributed* flag-definition policy: rather than an application having to define all flags in or near main(), each python module defines flags that are useful to it. When one python module imports another, it gains access to the other's flags. (This is implemented by having all modules share a common, global registry object containing all the flag information.) Flags are defined through the use of one of the DEFINE_xxx functions. The specific function used determines how the flag is parsed, checked, and optionally type-converted, when it's seen on the command line. IMPLEMENTATION: DEFINE_* creates a 'Flag' object and registers it with a 'FlagValues' object (typically the global FlagValues FLAGS, defined here). The 'FlagValues' object can scan the command line arguments and pass flag arguments to the corresponding 'Flag' objects for value-checking and type conversion. The converted flag values are available as attributes of the 'FlagValues' object. Code can access the flag through a FlagValues object, for instance gflags.FLAGS.myflag. Typically, the __main__ module passes the command line arguments to gflags.FLAGS for parsing. At bottom, this module calls getopt(), so getopt functionality is supported, including short- and long-style flags, and the use of -- to terminate flags. Methods defined by the flag module will throw 'FlagsError' exceptions. The exception argument will be a human-readable string. FLAG TYPES: This is a list of the DEFINE_*'s that you can do. All flags take a name, default value, help-string, and optional 'short' name (one-letter name). Some flags have other arguments, which are described with the flag. DEFINE_string: takes any input, and interprets it as a string. DEFINE_bool or DEFINE_boolean: typically does not take an argument: say --myflag to set FLAGS.myflag to true, or --nomyflag to set FLAGS.myflag to false. Alternately, you can say --myflag=true or --myflag=t or --myflag=1 or --myflag=false or --myflag=f or --myflag=0 DEFINE_float: takes an input and interprets it as a floating point number. Takes optional args lower_bound and upper_bound; if the number specified on the command line is out of range, it will raise a FlagError. DEFINE_integer: takes an input and interprets it as an integer. Takes optional args lower_bound and upper_bound as for floats. DEFINE_enum: takes a list of strings which represents legal values. If the command-line value is not in this list, raise a flag error. Otherwise, assign to FLAGS.flag as a string. DEFINE_list: Takes a comma-separated list of strings on the commandline. Stores them in a python list object. DEFINE_spaceseplist: Takes a space-separated list of strings on the commandline. Stores them in a python list object. Example: --myspacesepflag "foo bar baz" DEFINE_multistring: The same as DEFINE_string, except the flag can be specified more than once on the commandline. The result is a python list object (list of strings), even if the flag is only on the command line once. DEFINE_multi_int: The same as DEFINE_integer, except the flag can be specified more than once on the commandline. The result is a python list object (list of ints), even if the flag is only on the command line once. SPECIAL FLAGS: There are a few flags that have special meaning: --help prints a list of all the flags in a human-readable fashion --helpshort prints a list of all key flags (see below). --helpxml prints a list of all flags, in XML format. DO NOT parse the output of --help and --helpshort. Instead, parse the output of --helpxml. For more info, see "OUTPUT FOR --helpxml" below. --flagfile=foo read flags from file foo. --undefok=f1,f2 ignore unrecognized option errors for f1,f2. For boolean flags, you should use --undefok=boolflag, and --boolflag and --noboolflag will be accepted. Do not use --undefok=noboolflag. -- as in getopt(), terminates flag-processing FLAGS VALIDATORS: If your program: - requires flag X to be specified - needs flag Y to match a regular expression - or requires any more general constraint to be satisfied then validators are for you! Each validator represents a constraint over one flag, which is enforced starting from the initial parsing of the flags and until the program terminates. Also, lower_bound and upper_bound for numerical flags are enforced using flag validators. Howto: If you want to enforce a constraint over one flag, use flags.RegisterValidator(flag_name, checker, message='Flag validation failed', flag_values=FLAGS) After flag values are initially parsed, and after any change to the specified flag, method checker(flag_value) will be executed. If constraint is not satisfied, an IllegalFlagValue exception will be raised. See RegisterValidator's docstring for a detailed explanation on how to construct your own checker. EXAMPLE USAGE: FLAGS = flags.FLAGS flags.DEFINE_integer('my_version', 0, 'Version number.') flags.DEFINE_string('filename', None, 'Input file name', short_name='f') flags.RegisterValidator('my_version', lambda value: value % 2 == 0, message='--my_version must be divisible by 2') flags.MarkFlagAsRequired('filename') NOTE ON --flagfile: Flags may be loaded from text files in addition to being specified on the commandline. Any flags you don't feel like typing, throw them in a file, one flag per line, for instance: --myflag=myvalue --nomyboolean_flag You then specify your file with the special flag '--flagfile=somefile'. You CAN recursively nest flagfile= tokens OR use multiple files on the command line. Lines beginning with a single hash '#' or a double slash '//' are comments in your flagfile. Any flagfile=<file> will be interpreted as having a relative path from the current working directory rather than from the place the file was included from: myPythonScript.py --flagfile=config/somefile.cfg If somefile.cfg includes further --flagfile= directives, these will be referenced relative to the original CWD, not from the directory the including flagfile was found in! The caveat applies to people who are including a series of nested files in a different dir than they are executing out of. Relative path names are always from CWD, not from the directory of the parent include flagfile. We do now support '~' expanded directory names. Absolute path names ALWAYS work! EXAMPLE USAGE: import gflags FLAGS = gflags.FLAGS # Flag names are globally defined! So in general, we need to be # careful to pick names that are unlikely to be used by other libraries. # If there is a conflict, we'll get an error at import time. gflags.DEFINE_string('name', 'Mr. President', 'your name') gflags.DEFINE_integer('age', None, 'your age in years', lower_bound=0) gflags.DEFINE_boolean('debug', False, 'produces debugging output') gflags.DEFINE_enum('gender', 'male', ['male', 'female'], 'your gender') def main(argv): try: argv = FLAGS(argv) # parse flags except gflags.FlagsError, e: print '%s\\nUsage: %s ARGS\\n%s' % (e, sys.argv[0], FLAGS) sys.exit(1) if FLAGS.debug: print 'non-flag arguments:', argv print 'Happy Birthday', FLAGS.name if FLAGS.age is not None: print 'You are a %s, who is %d years old' % (FLAGS.gender, FLAGS.age) if __name__ == '__main__': main(sys.argv) KEY FLAGS: As we already explained, each module gains access to all flags defined by all the other modules it transitively imports. In the case of non-trivial scripts, this means a lot of flags ... For documentation purposes, it is good to identify the flags that are key (i.e., really important) to a module. Clearly, the concept of "key flag" is a subjective one. When trying to determine whether a flag is key to a module or not, assume that you are trying to explain your module to a potential user: which flags would you really like to mention first? We'll describe shortly how to declare which flags are key to a module. For the moment, assume we know the set of key flags for each module. Then, if you use the app.py module, you can use the --helpshort flag to print only the help for the flags that are key to the main module, in a human-readable format. NOTE: If you need to parse the flag help, do NOT use the output of --help / --helpshort. That output is meant for human consumption, and may be changed in the future. Instead, use --helpxml; flags that are key for the main module are marked there with a <key>yes</key> element. The set of key flags for a module M is composed of: 1. Flags defined by module M by calling a DEFINE_* function. 2. Flags that module M explictly declares as key by using the function DECLARE_key_flag(<flag_name>) 3. Key flags of other modules that M specifies by using the function ADOPT_module_key_flags(<other_module>) This is a "bulk" declaration of key flags: each flag that is key for <other_module> becomes key for the current module too. Notice that if you do not use the functions described at points 2 and 3 above, then --helpshort prints information only about the flags defined by the main module of our script. In many cases, this behavior is good enough. But if you move part of the main module code (together with the related flags) into a different module, then it is nice to use DECLARE_key_flag / ADOPT_module_key_flags and make sure --helpshort lists all relevant flags (otherwise, your code refactoring may confuse your users). Note: each of DECLARE_key_flag / ADOPT_module_key_flags has its own pluses and minuses: DECLARE_key_flag is more targeted and may lead a more focused --helpshort documentation. ADOPT_module_key_flags is good for cases when an entire module is considered key to the current script. Also, it does not require updates to client scripts when a new flag is added to the module. EXAMPLE USAGE 2 (WITH KEY FLAGS): Consider an application that contains the following three files (two auxiliary modules and a main module): File libfoo.py: import gflags gflags.DEFINE_integer('num_replicas', 3, 'Number of replicas to start') gflags.DEFINE_boolean('rpc2', True, 'Turn on the usage of RPC2.') ... some code ... File libbar.py: import gflags gflags.DEFINE_string('bar_gfs_path', '/gfs/path', 'Path to the GFS files for libbar.') gflags.DEFINE_string('email_for_bar_errors', 'bar-team@google.com', 'Email address for bug reports about module libbar.') gflags.DEFINE_boolean('bar_risky_hack', False, 'Turn on an experimental and buggy optimization.') ... some code ... File myscript.py: import gflags import libfoo import libbar gflags.DEFINE_integer('num_iterations', 0, 'Number of iterations.') # Declare that all flags that are key for libfoo are # key for this module too. gflags.ADOPT_module_key_flags(libfoo) # Declare that the flag --bar_gfs_path (defined in libbar) is key # for this module. gflags.DECLARE_key_flag('bar_gfs_path') ... some code ... When myscript is invoked with the flag --helpshort, the resulted help message lists information about all the key flags for myscript: --num_iterations, --num_replicas, --rpc2, and --bar_gfs_path (in addition to the special flags --help and --helpshort). Of course, myscript uses all the flags declared by it (in this case, just --num_replicas) or by any of the modules it transitively imports (e.g., the modules libfoo, libbar). E.g., it can access the value of FLAGS.bar_risky_hack, even if --bar_risky_hack is not declared as a key flag for myscript. OUTPUT FOR --helpxml: The --helpxml flag generates output with the following structure: <?xml version="1.0"?> <AllFlags> <program>PROGRAM_BASENAME</program> <usage>MAIN_MODULE_DOCSTRING</usage> (<flag> [<key>yes</key>] <file>DECLARING_MODULE</file> <name>FLAG_NAME</name> <meaning>FLAG_HELP_MESSAGE</meaning> <default>DEFAULT_FLAG_VALUE</default> <current>CURRENT_FLAG_VALUE</current> <type>FLAG_TYPE</type> [OPTIONAL_ELEMENTS] </flag>)* </AllFlags> Notes: 1. The output is intentionally similar to the output generated by the C++ command-line flag library. The few differences are due to the Python flags that do not have a C++ equivalent (at least not yet), e.g., DEFINE_list. 2. New XML elements may be added in the future. 3. DEFAULT_FLAG_VALUE is in serialized form, i.e., the string you can pass for this flag on the command-line. E.g., for a flag defined using DEFINE_list, this field may be foo,bar, not ['foo', 'bar']. 4. CURRENT_FLAG_VALUE is produced using str(). This means that the string 'false' will be represented in the same way as the boolean False. Using repr() would have removed this ambiguity and simplified parsing, but would have broken the compatibility with the C++ command-line flags. 5. OPTIONAL_ELEMENTS describe elements relevant for certain kinds of flags: lower_bound, upper_bound (for flags that specify bounds), enum_value (for enum flags), list_separator (for flags that consist of a list of values, separated by a special token). 6. We do not provide any example here: please use --helpxml instead. """ import cgi import getopt import os import re import string import sys import gflags_validators # Are we running at least python 2.2? try: if tuple(sys.version_info[:3]) < (2,2,0): raise NotImplementedError("requires python 2.2.0 or later") except AttributeError: # a very old python, that lacks sys.version_info raise NotImplementedError("requires python 2.2.0 or later") # If we're not running at least python 2.2.1, define True, False, and bool. # Thanks, Guido, for the code. try: True, False, bool except NameError: False = 0 True = 1 def bool(x): if x: return True else: return False # Are we running under pychecker? _RUNNING_PYCHECKER = 'pychecker.python' in sys.modules def _GetCallingModule(): """Returns the name of the module that's calling into this module. We generally use this function to get the name of the module calling a DEFINE_foo... function. """ # Walk down the stack to find the first globals dict that's not ours. for depth in range(1, sys.getrecursionlimit()): if not sys._getframe(depth).f_globals is globals(): globals_for_frame = sys._getframe(depth).f_globals module_name = _GetModuleObjectAndName(globals_for_frame)[1] if module_name is not None: return module_name raise AssertionError("No module was found") def _GetThisModuleObjectAndName(): """Returns: (module object, module name) for this module.""" return _GetModuleObjectAndName(globals()) # module exceptions: class FlagsError(Exception): """The base class for all flags errors.""" pass class DuplicateFlag(FlagsError): """Raised if there is a flag naming conflict.""" pass class DuplicateFlagCannotPropagateNoneToSwig(DuplicateFlag): """Special case of DuplicateFlag -- SWIG flag value can't be set to None. This can be raised when a duplicate flag is created. Even if allow_override is True, we still abort if the new value is None, because it's currently impossible to pass None default value back to SWIG. See FlagValues.SetDefault for details. """ pass # A DuplicateFlagError conveys more information than a # DuplicateFlag. Since there are external modules that create # DuplicateFlags, the interface to DuplicateFlag shouldn't change. class DuplicateFlagError(DuplicateFlag): def __init__(self, flagname, flag_values): self.flagname = flagname message = "The flag '%s' is defined twice." % self.flagname flags_by_module = flag_values.FlagsByModuleDict() for module in flags_by_module: for flag in flags_by_module[module]: if flag.name == flagname or flag.short_name == flagname: message = message + " First from " + module + "," break message = message + " Second from " + _GetCallingModule() DuplicateFlag.__init__(self, message) class IllegalFlagValue(FlagsError): """The flag command line argument is illegal.""" pass class UnrecognizedFlag(FlagsError): """Raised if a flag is unrecognized.""" pass # An UnrecognizedFlagError conveys more information than an UnrecognizedFlag. # Since there are external modules that create DuplicateFlags, the interface to # DuplicateFlag shouldn't change. The flagvalue will be assigned the full value # of the flag and its argument, if any, allowing handling of unrecognzed flags # in an exception handler. # If flagvalue is the empty string, then this exception is an due to a # reference to a flag that was not already defined. class UnrecognizedFlagError(UnrecognizedFlag): def __init__(self, flagname, flagvalue=''): self.flagname = flagname self.flagvalue = flagvalue UnrecognizedFlag.__init__( self, "Unknown command line flag '%s'" % flagname) # Global variable used by expvar _exported_flags = {} _help_width = 80 # width of help output def GetHelpWidth(): """Returns: an integer, the width of help lines that is used in TextWrap.""" return _help_width def CutCommonSpacePrefix(text): """Removes a common space prefix from the lines of a multiline text. If the first line does not start with a space, it is left as it is and only in the remaining lines a common space prefix is being searched for. That means the first line will stay untouched. This is especially useful to turn doc strings into help texts. This is because some people prefer to have the doc comment start already after the apostrophy and then align the following lines while others have the apostrophies on a seperately line. The function also drops trailing empty lines and ignores empty lines following the initial content line while calculating the initial common whitespace. Args: text: text to work on Returns: the resulting text """ text_lines = text.splitlines() # Drop trailing empty lines while text_lines and not text_lines[-1]: text_lines = text_lines[:-1] if text_lines: # We got some content, is the first line starting with a space? if text_lines[0] and text_lines[0][0].isspace(): text_first_line = [] else: text_first_line = [text_lines.pop(0)] # Calculate length of common leading whitesppace (only over content lines) common_prefix = os.path.commonprefix([line for line in text_lines if line]) space_prefix_len = len(common_prefix) - len(common_prefix.lstrip()) # If we have a common space prefix, drop it from all lines if space_prefix_len: for index in xrange(len(text_lines)): if text_lines[index]: text_lines[index] = text_lines[index][space_prefix_len:] return '\n'.join(text_first_line + text_lines) return '' def TextWrap(text, length=None, indent='', firstline_indent=None, tabs=' '): """Wraps a given text to a maximum line length and returns it. We turn lines that only contain whitespaces into empty lines. We keep new lines and tabs (e.g., we do not treat tabs as spaces). Args: text: text to wrap length: maximum length of a line, includes indentation if this is None then use GetHelpWidth() indent: indent for all but first line firstline_indent: indent for first line; if None, fall back to indent tabs: replacement for tabs Returns: wrapped text Raises: FlagsError: if indent not shorter than length FlagsError: if firstline_indent not shorter than length """ # Get defaults where callee used None if length is None: length = GetHelpWidth() if indent is None: indent = '' if len(indent) >= length: raise FlagsError('Indent must be shorter than length') # In line we will be holding the current line which is to be started # with indent (or firstline_indent if available) and then appended # with words. if firstline_indent is None: firstline_indent = '' line = indent else: line = firstline_indent if len(firstline_indent) >= length: raise FlagsError('First iline indent must be shorter than length') # If the callee does not care about tabs we simply convert them to # spaces If callee wanted tabs to be single space then we do that # already here. if not tabs or tabs == ' ': text = text.replace('\t', ' ') else: tabs_are_whitespace = not tabs.strip() line_regex = re.compile('([ ]*)(\t*)([^ \t]+)', re.MULTILINE) # Split the text into lines and the lines with the regex above. The # resulting lines are collected in result[]. For each split we get the # spaces, the tabs and the next non white space (e.g. next word). result = [] for text_line in text.splitlines(): # Store result length so we can find out whether processing the next # line gave any new content old_result_len = len(result) # Process next line with line_regex. For optimization we do an rstrip(). # - process tabs (changes either line or word, see below) # - process word (first try to squeeze on line, then wrap or force wrap) # Spaces found on the line are ignored, they get added while wrapping as # needed. for spaces, current_tabs, word in line_regex.findall(text_line.rstrip()): # If tabs weren't converted to spaces, handle them now if current_tabs: # If the last thing we added was a space anyway then drop # it. But let's not get rid of the indentation. if (((result and line != indent) or (not result and line != firstline_indent)) and line[-1] == ' '): line = line[:-1] # Add the tabs, if that means adding whitespace, just add it at # the line, the rstrip() code while shorten the line down if # necessary if tabs_are_whitespace: line += tabs * len(current_tabs) else: # if not all tab replacement is whitespace we prepend it to the word word = tabs * len(current_tabs) + word # Handle the case where word cannot be squeezed onto current last line if len(line) + len(word) > length and len(indent) + len(word) <= length: result.append(line.rstrip()) line = indent + word word = '' # No space left on line or can we append a space? if len(line) + 1 >= length: result.append(line.rstrip()) line = indent else: line += ' ' # Add word and shorten it up to allowed line length. Restart next # line with indent and repeat, or add a space if we're done (word # finished) This deals with words that caanot fit on one line # (e.g. indent + word longer than allowed line length). while len(line) + len(word) >= length: line += word result.append(line[:length]) word = line[length:] line = indent # Default case, simply append the word and a space if word: line += word + ' ' # End of input line. If we have content we finish the line. If the # current line is just the indent but we had content in during this # original line then we need to add an emoty line. if (result and line != indent) or (not result and line != firstline_indent): result.append(line.rstrip()) elif len(result) == old_result_len: result.append('') line = indent return '\n'.join(result) def DocToHelp(doc): """Takes a __doc__ string and reformats it as help.""" # Get rid of starting and ending white space. Using lstrip() or even # strip() could drop more than maximum of first line and right space # of last line. doc = doc.strip() # Get rid of all empty lines whitespace_only_line = re.compile('^[ \t]+$', re.M) doc = whitespace_only_line.sub('', doc) # Cut out common space at line beginnings doc = CutCommonSpacePrefix(doc) # Just like this module's comment, comments tend to be aligned somehow. # In other words they all start with the same amount of white space # 1) keep double new lines # 2) keep ws after new lines if not empty line # 3) all other new lines shall be changed to a space # Solution: Match new lines between non white space and replace with space. doc = re.sub('(?<=\S)\n(?=\S)', ' ', doc, re.M) return doc def _GetModuleObjectAndName(globals_dict): """Returns the module that defines a global environment, and its name. Args: globals_dict: A dictionary that should correspond to an environment providing the values of the globals. Returns: A pair consisting of (1) module object and (2) module name (a string). Returns (None, None) if the module could not be identified. """ # The use of .items() (instead of .iteritems()) is NOT a mistake: if # a parallel thread imports a module while we iterate over # .iteritems() (not nice, but possible), we get a RuntimeError ... # Hence, we use the slightly slower but safer .items(). for name, module in sys.modules.items(): if getattr(module, '__dict__', None) is globals_dict: if name == '__main__': # Pick a more informative name for the main module. name = sys.argv[0] return (module, name) return (None, None) def _GetMainModule(): """Returns the name of the module from which execution started.""" for depth in range(1, sys.getrecursionlimit()): try: globals_of_main = sys._getframe(depth).f_globals except ValueError: return _GetModuleObjectAndName(globals_of_main)[1] raise AssertionError("No module was found") class FlagValues: """Registry of 'Flag' objects. A 'FlagValues' can then scan command line arguments, passing flag arguments through to the 'Flag' objects that it owns. It also provides easy access to the flag values. Typically only one 'FlagValues' object is needed by an application: gflags.FLAGS This class is heavily overloaded: 'Flag' objects are registered via __setitem__: FLAGS['longname'] = x # register a new flag The .value attribute of the registered 'Flag' objects can be accessed as attributes of this 'FlagValues' object, through __getattr__. Both the long and short name of the original 'Flag' objects can be used to access its value: FLAGS.longname # parsed flag value FLAGS.x # parsed flag value (short name) Command line arguments are scanned and passed to the registered 'Flag' objects through the __call__ method. Unparsed arguments, including argv[0] (e.g. the program name) are returned. argv = FLAGS(sys.argv) # scan command line arguments The original registered Flag objects can be retrieved through the use of the dictionary-like operator, __getitem__: x = FLAGS['longname'] # access the registered Flag object The str() operator of a 'FlagValues' object provides help for all of the registered 'Flag' objects. """ def __init__(self): # Since everything in this class is so heavily overloaded, the only # way of defining and using fields is to access __dict__ directly. # Dictionary: flag name (string) -> Flag object. self.__dict__['__flags'] = {} # Dictionary: module name (string) -> list of Flag objects that are defined # by that module. self.__dict__['__flags_by_module'] = {} # Dictionary: module name (string) -> list of Flag objects that are # key for that module. self.__dict__['__key_flags_by_module'] = {} # Set if we should use new style gnu_getopt rather than getopt when parsing # the args. Only possible with Python 2.3+ self.UseGnuGetOpt(False) def UseGnuGetOpt(self, use_gnu_getopt=True): self.__dict__['__use_gnu_getopt'] = use_gnu_getopt def IsGnuGetOpt(self): return self.__dict__['__use_gnu_getopt'] def FlagDict(self): return self.__dict__['__flags'] def FlagsByModuleDict(self): """Returns the dictionary of module_name -> list of defined flags. Returns: A dictionary. Its keys are module names (strings). Its values are lists of Flag objects. """ return self.__dict__['__flags_by_module'] def KeyFlagsByModuleDict(self): """Returns the dictionary of module_name -> list of key flags. Returns: A dictionary. Its keys are module names (strings). Its values are lists of Flag objects. """ return self.__dict__['__key_flags_by_module'] def _RegisterFlagByModule(self, module_name, flag): """Records the module that defines a specific flag. We keep track of which flag is defined by which module so that we can later sort the flags by module. Args: module_name: A string, the name of a Python module. flag: A Flag object, a flag that is key to the module. """ flags_by_module = self.FlagsByModuleDict() flags_by_module.setdefault(module_name, []).append(flag) def _RegisterKeyFlagForModule(self, module_name, flag): """Specifies that a flag is a key flag for a module. Args: module_name: A string, the name of a Python module. flag: A Flag object, a flag that is key to the module. """ key_flags_by_module = self.KeyFlagsByModuleDict() # The list of key flags for the module named module_name. key_flags = key_flags_by_module.setdefault(module_name, []) # Add flag, but avoid duplicates. if flag not in key_flags: key_flags.append(flag) def _GetFlagsDefinedByModule(self, module): """Returns the list of flags defined by a module. Args: module: A module object or a module name (a string). Returns: A new list of Flag objects. Caller may update this list as he wishes: none of those changes will affect the internals of this FlagValue object. """ if not isinstance(module, str): module = module.__name__ return list(self.FlagsByModuleDict().get(module, [])) def _GetKeyFlagsForModule(self, module): """Returns the list of key flags for a module. Args: module: A module object or a module name (a string) Returns: A new list of Flag objects. Caller may update this list as he wishes: none of those changes will affect the internals of this FlagValue object. """ if not isinstance(module, str): module = module.__name__ # Any flag is a key flag for the module that defined it. NOTE: # key_flags is a fresh list: we can update it without affecting the # internals of this FlagValues object. key_flags = self._GetFlagsDefinedByModule(module) # Take into account flags explicitly declared as key for a module. for flag in self.KeyFlagsByModuleDict().get(module, []): if flag not in key_flags: key_flags.append(flag) return key_flags def AppendFlagValues(self, flag_values): """Appends flags registered in another FlagValues instance. Args: flag_values: registry to copy from """ for flag_name, flag in flag_values.FlagDict().iteritems(): # Each flags with shortname appears here twice (once under its # normal name, and again with its short name). To prevent # problems (DuplicateFlagError) with double flag registration, we # perform a check to make sure that the entry we're looking at is # for its normal name. if flag_name == flag.name: self[flag_name] = flag def RemoveFlagValues(self, flag_values): """Remove flags that were previously appended from another FlagValues. Args: flag_values: registry containing flags to remove. """ for flag_name in flag_values.FlagDict(): self.__delattr__(flag_name) def __setitem__(self, name, flag): """Registers a new flag variable.""" fl = self.FlagDict() if not isinstance(flag, Flag): raise IllegalFlagValue(flag) if not isinstance(name, type("")): raise FlagsError("Flag name must be a string") if len(name) == 0: raise FlagsError("Flag name cannot be empty") # If running under pychecker, duplicate keys are likely to be # defined. Disable check for duplicate keys when pycheck'ing. if (fl.has_key(name) and not flag.allow_override and not fl[name].allow_override and not _RUNNING_PYCHECKER): raise DuplicateFlagError(name, self) short_name = flag.short_name if short_name is not None: if (fl.has_key(short_name) and not flag.allow_override and not fl[short_name].allow_override and not _RUNNING_PYCHECKER): raise DuplicateFlagError(short_name, self) fl[short_name] = flag fl[name] = flag global _exported_flags _exported_flags[name] = flag def __getitem__(self, name): """Retrieves the Flag object for the flag --name.""" return self.FlagDict()[name] def __getattr__(self, name): """Retrieves the 'value' attribute of the flag --name.""" fl = self.FlagDict() if not fl.has_key(name): raise AttributeError(name) return fl[name].value def __setattr__(self, name, value): """Sets the 'value' attribute of the flag --name.""" fl = self.FlagDict() fl[name].value = value self._AssertValidators(fl[name].validators) return value def _AssertAllValidators(self): all_validators = set() for flag in self.FlagDict().itervalues(): for validator in flag.validators: all_validators.add(validator) self._AssertValidators(all_validators) def _AssertValidators(self, validators): """Assert if all validators in the list are satisfied. Asserts validators in the order they were created. Args: validators: Iterable(gflags_validators.Validator), validators to be verified Raises: AttributeError: if validators work with a non-existing flag. IllegalFlagValue: if validation fails for at least one validator """ for validator in sorted( validators, key=lambda validator: validator.insertion_index): try: validator.Verify(self) except gflags_validators.Error, e: message = validator.PrintFlagsWithValues(self) raise IllegalFlagValue('%s: %s' % (message, str(e))) def _FlagIsRegistered(self, flag_obj): """Checks whether a Flag object is registered under some name. Note: this is non trivial: in addition to its normal name, a flag may have a short name too. In self.FlagDict(), both the normal and the short name are mapped to the same flag object. E.g., calling only "del FLAGS.short_name" is not unregistering the corresponding Flag object (it is still registered under the longer name). Args: flag_obj: A Flag object. Returns: A boolean: True iff flag_obj is registered under some name. """ flag_dict = self.FlagDict() # Check whether flag_obj is registered under its long name. name = flag_obj.name if flag_dict.get(name, None) == flag_obj: return True # Check whether flag_obj is registered under its short name. short_name = flag_obj.short_name if (short_name is not None and flag_dict.get(short_name, None) == flag_obj): return True # The flag cannot be registered under any other name, so we do not # need to do a full search through the values of self.FlagDict(). return False def __delattr__(self, flag_name): """Deletes a previously-defined flag from a flag object. This method makes sure we can delete a flag by using del flag_values_object.<flag_name> E.g., flags.DEFINE_integer('foo', 1, 'Integer flag.') del flags.FLAGS.foo Args: flag_name: A string, the name of the flag to be deleted. Raises: AttributeError: When there is no registered flag named flag_name. """ fl = self.FlagDict() if flag_name not in fl: raise AttributeError(flag_name) flag_obj = fl[flag_name] del fl[flag_name] if not self._FlagIsRegistered(flag_obj): # If the Flag object indicated by flag_name is no longer # registered (please see the docstring of _FlagIsRegistered), then # we delete the occurences of the flag object in all our internal # dictionaries. self.__RemoveFlagFromDictByModule(self.FlagsByModuleDict(), flag_obj) self.__RemoveFlagFromDictByModule(self.KeyFlagsByModuleDict(), flag_obj) def __RemoveFlagFromDictByModule(self, flags_by_module_dict, flag_obj): """Removes a flag object from a module -> list of flags dictionary. Args: flags_by_module_dict: A dictionary that maps module names to lists of flags. flag_obj: A flag object. """ for unused_module, flags_in_module in flags_by_module_dict.iteritems(): # while (as opposed to if) takes care of multiple occurences of a # flag in the list for the same module. while flag_obj in flags_in_module: flags_in_module.remove(flag_obj) def SetDefault(self, name, value): """Changes the default value of the named flag object.""" fl = self.FlagDict() if not fl.has_key(name): raise AttributeError(name) fl[name].SetDefault(value) self._AssertValidators(fl[name].validators) def __contains__(self, name): """Returns True if name is a value (flag) in the dict.""" return name in self.FlagDict() has_key = __contains__ # a synonym for __contains__() def __iter__(self): return self.FlagDict().iterkeys() def __call__(self, argv): """Parses flags from argv; stores parsed flags into this FlagValues object. All unparsed arguments are returned. Flags are parsed using the GNU Program Argument Syntax Conventions, using getopt: http://www.gnu.org/software/libc/manual/html_mono/libc.html#Getopt Args: argv: argument list. Can be of any type that may be converted to a list. Returns: The list of arguments not parsed as options, including argv[0] Raises: FlagsError: on any parsing error """ # Support any sequence type that can be converted to a list argv = list(argv) shortopts = "" longopts = [] fl = self.FlagDict() # This pre parses the argv list for --flagfile=<> options. argv = argv[:1] + self.ReadFlagsFromFiles(argv[1:], force_gnu=False) # Correct the argv to support the google style of passing boolean # parameters. Boolean parameters may be passed by using --mybool, # --nomybool, --mybool=(true|false|1|0). getopt does not support # having options that may or may not have a parameter. We replace # instances of the short form --mybool and --nomybool with their # full forms: --mybool=(true|false). original_argv = list(argv) # list() makes a copy shortest_matches = None for name, flag in fl.items(): if not flag.boolean: continue if shortest_matches is None: # Determine the smallest allowable prefix for all flag names shortest_matches = self.ShortestUniquePrefixes(fl) no_name = 'no' + name prefix = shortest_matches[name] no_prefix = shortest_matches[no_name] # Replace all occurences of this boolean with extended forms for arg_idx in range(1, len(argv)): arg = argv[arg_idx] if arg.find('=') >= 0: continue if arg.startswith('--'+prefix) and ('--'+name).startswith(arg): argv[arg_idx] = ('--%s=true' % name) elif arg.startswith('--'+no_prefix) and ('--'+no_name).startswith(arg): argv[arg_idx] = ('--%s=false' % name) # Loop over all of the flags, building up the lists of short options # and long options that will be passed to getopt. Short options are # specified as a string of letters, each letter followed by a colon # if it takes an argument. Long options are stored in an array of # strings. Each string ends with an '=' if it takes an argument. for name, flag in fl.items(): longopts.append(name + "=") if len(name) == 1: # one-letter option: allow short flag type also shortopts += name if not flag.boolean: shortopts += ":" longopts.append('undefok=') undefok_flags = [] # In case --undefok is specified, loop to pick up unrecognized # options one by one. unrecognized_opts = [] args = argv[1:] while True: try: if self.__dict__['__use_gnu_getopt']: optlist, unparsed_args = getopt.gnu_getopt(args, shortopts, longopts) else: optlist, unparsed_args = getopt.getopt(args, shortopts, longopts) break except getopt.GetoptError, e: if not e.opt or e.opt in fl: # Not an unrecognized option, reraise the exception as a FlagsError raise FlagsError(e) # Remove offender from args and try again for arg_index in range(len(args)): if ((args[arg_index] == '--' + e.opt) or (args[arg_index] == '-' + e.opt) or (args[arg_index].startswith('--' + e.opt + '='))): unrecognized_opts.append((e.opt, args[arg_index])) args = args[0:arg_index] + args[arg_index+1:] break else: # We should have found the option, so we don't expect to get # here. We could assert, but raising the original exception # might work better. raise FlagsError(e) for name, arg in optlist: if name == '--undefok': flag_names = arg.split(',') undefok_flags.extend(flag_names) # For boolean flags, if --undefok=boolflag is specified, then we should # also accept --noboolflag, in addition to --boolflag. # Since we don't know the type of the undefok'd flag, this will affect # non-boolean flags as well. # NOTE: You shouldn't use --undefok=noboolflag, because then we will # accept --nonoboolflag here. We are choosing not to do the conversion # from noboolflag -> boolflag because of the ambiguity that flag names # can start with 'no'. undefok_flags.extend('no' + name for name in flag_names) continue if name.startswith('--'): # long option name = name[2:] short_option = 0 else: # short option name = name[1:] short_option = 1 if fl.has_key(name): flag = fl[name] if flag.boolean and short_option: arg = 1 flag.Parse(arg) # If there were unrecognized options, raise an exception unless # the options were named via --undefok. for opt, value in unrecognized_opts: if opt not in undefok_flags: raise UnrecognizedFlagError(opt, value) if unparsed_args: if self.__dict__['__use_gnu_getopt']: # if using gnu_getopt just return the program name + remainder of argv. ret_val = argv[:1] + unparsed_args else: # unparsed_args becomes the first non-flag detected by getopt to # the end of argv. Because argv may have been modified above, # return original_argv for this region. ret_val = argv[:1] + original_argv[-len(unparsed_args):] else: ret_val = argv[:1] self._AssertAllValidators() return ret_val def Reset(self): """Resets the values to the point before FLAGS(argv) was called.""" for f in self.FlagDict().values(): f.Unparse() def RegisteredFlags(self): """Returns: a list of the names and short names of all registered flags.""" return self.FlagDict().keys() def FlagValuesDict(self): """Returns: a dictionary that maps flag names to flag values.""" flag_values = {} for flag_name in self.RegisteredFlags(): flag = self.FlagDict()[flag_name] flag_values[flag_name] = flag.value return flag_values def __str__(self): """Generates a help string for all known flags.""" return self.GetHelp() def GetHelp(self, prefix=''): """Generates a help string for all known flags.""" helplist = [] flags_by_module = self.FlagsByModuleDict() if flags_by_module: modules = flags_by_module.keys() modules.sort() # Print the help for the main module first, if possible. main_module = _GetMainModule() if main_module in modules: modules.remove(main_module) modules = [main_module] + modules for module in modules: self.__RenderOurModuleFlags(module, helplist) self.__RenderModuleFlags('gflags', _SPECIAL_FLAGS.FlagDict().values(), helplist) else: # Just print one long list of flags. self.__RenderFlagList( self.FlagDict().values() + _SPECIAL_FLAGS.FlagDict().values(), helplist, prefix) return '\n'.join(helplist) def __RenderModuleFlags(self, module, flags, output_lines, prefix=""): """Generates a help string for a given module.""" if not isinstance(module, str): module = module.__name__ output_lines.append('\n%s%s:' % (prefix, module)) self.__RenderFlagList(flags, output_lines, prefix + " ") def __RenderOurModuleFlags(self, module, output_lines, prefix=""): """Generates a help string for a given module.""" flags = self._GetFlagsDefinedByModule(module) if flags: self.__RenderModuleFlags(module, flags, output_lines, prefix) def __RenderOurModuleKeyFlags(self, module, output_lines, prefix=""): """Generates a help string for the key flags of a given module. Args: module: A module object or a module name (a string). output_lines: A list of strings. The generated help message lines will be appended to this list. prefix: A string that is prepended to each generated help line. """ key_flags = self._GetKeyFlagsForModule(module) if key_flags: self.__RenderModuleFlags(module, key_flags, output_lines, prefix) def ModuleHelp(self, module): """Describe the key flags of a module. Args: module: A module object or a module name (a string). Returns: string describing the key flags of a module. """ helplist = [] self.__RenderOurModuleKeyFlags(module, helplist) return '\n'.join(helplist) def MainModuleHelp(self): """Describe the key flags of the main module. Returns: string describing the key flags of a module. """ return self.ModuleHelp(_GetMainModule()) def __RenderFlagList(self, flaglist, output_lines, prefix=" "): fl = self.FlagDict() special_fl = _SPECIAL_FLAGS.FlagDict() flaglist = [(flag.name, flag) for flag in flaglist] flaglist.sort() flagset = {} for (name, flag) in flaglist: # It's possible this flag got deleted or overridden since being # registered in the per-module flaglist. Check now against the # canonical source of current flag information, the FlagDict. if fl.get(name, None) != flag and special_fl.get(name, None) != flag: # a different flag is using this name now continue # only print help once if flagset.has_key(flag): continue flagset[flag] = 1 flaghelp = "" if flag.short_name: flaghelp += "-%s," % flag.short_name if flag.boolean: flaghelp += "--[no]%s" % flag.name + ":" else: flaghelp += "--%s" % flag.name + ":" flaghelp += " " if flag.help: flaghelp += flag.help flaghelp = TextWrap(flaghelp, indent=prefix+" ", firstline_indent=prefix) if flag.default_as_str: flaghelp += "\n" flaghelp += TextWrap("(default: %s)" % flag.default_as_str, indent=prefix+" ") if flag.parser.syntactic_help: flaghelp += "\n" flaghelp += TextWrap("(%s)" % flag.parser.syntactic_help, indent=prefix+" ") output_lines.append(flaghelp) def get(self, name, default): """Returns the value of a flag (if not None) or a default value. Args: name: A string, the name of a flag. default: Default value to use if the flag value is None. """ value = self.__getattr__(name) if value is not None: # Can't do if not value, b/c value might be '0' or "" return value else: return default def ShortestUniquePrefixes(self, fl): """Returns: dictionary; maps flag names to their shortest unique prefix.""" # Sort the list of flag names sorted_flags = [] for name, flag in fl.items(): sorted_flags.append(name) if flag.boolean: sorted_flags.append('no%s' % name) sorted_flags.sort() # For each name in the sorted list, determine the shortest unique # prefix by comparing itself to the next name and to the previous # name (the latter check uses cached info from the previous loop). shortest_matches = {} prev_idx = 0 for flag_idx in range(len(sorted_flags)): curr = sorted_flags[flag_idx] if flag_idx == (len(sorted_flags) - 1): next = None else: next = sorted_flags[flag_idx+1] next_len = len(next) for curr_idx in range(len(curr)): if (next is None or curr_idx >= next_len or curr[curr_idx] != next[curr_idx]): # curr longer than next or no more chars in common shortest_matches[curr] = curr[:max(prev_idx, curr_idx) + 1] prev_idx = curr_idx break else: # curr shorter than (or equal to) next shortest_matches[curr] = curr prev_idx = curr_idx + 1 # next will need at least one more char return shortest_matches def __IsFlagFileDirective(self, flag_string): """Checks whether flag_string contain a --flagfile=<foo> directive.""" if isinstance(flag_string, type("")): if flag_string.startswith('--flagfile='): return 1 elif flag_string == '--flagfile': return 1 elif flag_string.startswith('-flagfile='): return 1 elif flag_string == '-flagfile': return 1 else: return 0 return 0 def ExtractFilename(self, flagfile_str): """Returns filename from a flagfile_str of form -[-]flagfile=filename. The cases of --flagfile foo and -flagfile foo shouldn't be hitting this function, as they are dealt with in the level above this function. """ if flagfile_str.startswith('--flagfile='): return os.path.expanduser((flagfile_str[(len('--flagfile=')):]).strip()) elif flagfile_str.startswith('-flagfile='): return os.path.expanduser((flagfile_str[(len('-flagfile=')):]).strip()) else: raise FlagsError('Hit illegal --flagfile type: %s' % flagfile_str) def __GetFlagFileLines(self, filename, parsed_file_list): """Returns the useful (!=comments, etc) lines from a file with flags. Args: filename: A string, the name of the flag file. parsed_file_list: A list of the names of the files we have already read. MUTATED BY THIS FUNCTION. Returns: List of strings. See the note below. NOTE(springer): This function checks for a nested --flagfile=<foo> tag and handles the lower file recursively. It returns a list of all the lines that _could_ contain command flags. This is EVERYTHING except whitespace lines and comments (lines starting with '#' or '//'). """ line_list = [] # All line from flagfile. flag_line_list = [] # Subset of lines w/o comments, blanks, flagfile= tags. try: file_obj = open(filename, 'r') except IOError, e_msg: print e_msg print 'ERROR:: Unable to open flagfile: %s' % (filename) return flag_line_list line_list = file_obj.readlines() file_obj.close() parsed_file_list.append(filename) # This is where we check each line in the file we just read. for line in line_list: if line.isspace(): pass # Checks for comment (a line that starts with '#'). elif line.startswith('#') or line.startswith('//'): pass # Checks for a nested "--flagfile=<bar>" flag in the current file. # If we find one, recursively parse down into that file. elif self.__IsFlagFileDirective(line): sub_filename = self.ExtractFilename(line) # We do a little safety check for reparsing a file we've already done. if not sub_filename in parsed_file_list: included_flags = self.__GetFlagFileLines(sub_filename, parsed_file_list) flag_line_list.extend(included_flags) else: # Case of hitting a circularly included file. print >>sys.stderr, ('Warning: Hit circular flagfile dependency: %s' % sub_filename) else: # Any line that's not a comment or a nested flagfile should get # copied into 2nd position. This leaves earlier arguements # further back in the list, thus giving them higher priority. flag_line_list.append(line.strip()) return flag_line_list def ReadFlagsFromFiles(self, argv, force_gnu=True): """Processes command line args, but also allow args to be read from file. Args: argv: A list of strings, usually sys.argv[1:], which may contain one or more flagfile directives of the form --flagfile="./filename". Note that the name of the program (sys.argv[0]) should be omitted. force_gnu: If False, --flagfile parsing obeys normal flag semantics. If True, --flagfile parsing instead follows gnu_getopt semantics. *** WARNING *** force_gnu=False may become the future default! Returns: A new list which has the original list combined with what we read from any flagfile(s). References: Global gflags.FLAG class instance. This function should be called before the normal FLAGS(argv) call. This function scans the input list for a flag that looks like: --flagfile=<somefile>. Then it opens <somefile>, reads all valid key and value pairs and inserts them into the input list between the first item of the list and any subsequent items in the list. Note that your application's flags are still defined the usual way using gflags DEFINE_flag() type functions. Notes (assuming we're getting a commandline of some sort as our input): --> Flags from the command line argv _should_ always take precedence! --> A further "--flagfile=<otherfile.cfg>" CAN be nested in a flagfile. It will be processed after the parent flag file is done. --> For duplicate flags, first one we hit should "win". --> In a flagfile, a line beginning with # or // is a comment. --> Entirely blank lines _should_ be ignored. """ parsed_file_list = [] rest_of_args = argv new_argv = [] while rest_of_args: current_arg = rest_of_args[0] rest_of_args = rest_of_args[1:] if self.__IsFlagFileDirective(current_arg): # This handles the case of -(-)flagfile foo. In this case the # next arg really is part of this one. if current_arg == '--flagfile' or current_arg == '-flagfile': if not rest_of_args: raise IllegalFlagValue('--flagfile with no argument') flag_filename = os.path.expanduser(rest_of_args[0]) rest_of_args = rest_of_args[1:] else: # This handles the case of (-)-flagfile=foo. flag_filename = self.ExtractFilename(current_arg) new_argv[0:0] = self.__GetFlagFileLines(flag_filename, parsed_file_list) else: new_argv.append(current_arg) # Stop parsing after '--', like getopt and gnu_getopt. if current_arg == '--': break # Stop parsing after a non-flag, like getopt. if not current_arg.startswith('-'): if not force_gnu and not self.__dict__['__use_gnu_getopt']: break if rest_of_args: new_argv.extend(rest_of_args) return new_argv def FlagsIntoString(self): """Returns a string with the flags assignments from this FlagValues object. This function ignores flags whose value is None. Each flag assignment is separated by a newline. NOTE: MUST mirror the behavior of the C++ function CommandlineFlagsIntoString from google3/base/commandlineflags.cc. """ s = '' for flag in self.FlagDict().values(): if flag.value is not None: s += flag.Serialize() + '\n' return s def AppendFlagsIntoFile(self, filename): """Appends all flags assignments from this FlagInfo object to a file. Output will be in the format of a flagfile. NOTE: MUST mirror the behavior of the C++ version of AppendFlagsIntoFile from google3/base/commandlineflags.cc. """ out_file = open(filename, 'a') out_file.write(self.FlagsIntoString()) out_file.close() def WriteHelpInXMLFormat(self, outfile=None): """Outputs flag documentation in XML format. NOTE: We use element names that are consistent with those used by the C++ command-line flag library, from google3/base/commandlineflags_reporting.cc. We also use a few new elements (e.g., <key>), but we do not interfere / overlap with existing XML elements used by the C++ library. Please maintain this consistency. Args: outfile: File object we write to. Default None means sys.stdout. """ outfile = outfile or sys.stdout outfile.write('<?xml version=\"1.0\"?>\n') outfile.write('<AllFlags>\n') indent = ' ' _WriteSimpleXMLElement(outfile, 'program', os.path.basename(sys.argv[0]), indent) usage_doc = sys.modules['__main__'].__doc__ if not usage_doc: usage_doc = '\nUSAGE: %s [flags]\n' % sys.argv[0] else: usage_doc = usage_doc.replace('%s', sys.argv[0]) _WriteSimpleXMLElement(outfile, 'usage', usage_doc, indent) # Get list of key flags for the main module. key_flags = self._GetKeyFlagsForModule(_GetMainModule()) # Sort flags by declaring module name and next by flag name. flags_by_module = self.FlagsByModuleDict() all_module_names = list(flags_by_module.keys()) all_module_names.sort() for module_name in all_module_names: flag_list = [(f.name, f) for f in flags_by_module[module_name]] flag_list.sort() for unused_flag_name, flag in flag_list: is_key = flag in key_flags flag.WriteInfoInXMLFormat(outfile, module_name, is_key=is_key, indent=indent) outfile.write('</AllFlags>\n') outfile.flush() def AddValidator(self, validator): """Register new flags validator to be checked. Args: validator: gflags_validators.Validator Raises: AttributeError: if validators work with a non-existing flag. """ for flag_name in validator.GetFlagsNames(): flag = self.FlagDict()[flag_name] flag.validators.append(validator) # end of FlagValues definition # The global FlagValues instance FLAGS = FlagValues() def _MakeXMLSafe(s): """Escapes <, >, and & from s, and removes XML 1.0-illegal chars.""" s = cgi.escape(s) # Escape <, >, and & # Remove characters that cannot appear in an XML 1.0 document # (http://www.w3.org/TR/REC-xml/#charsets). # # NOTE: if there are problems with current solution, one may move to # XML 1.1, which allows such chars, if they're entity-escaped (&#xHH;). s = re.sub(r'[\x00-\x08\x0b\x0c\x0e-\x1f]', '', s) return s def _WriteSimpleXMLElement(outfile, name, value, indent): """Writes a simple XML element. Args: outfile: File object we write the XML element to. name: A string, the name of XML element. value: A Python object, whose string representation will be used as the value of the XML element. indent: A string, prepended to each line of generated output. """ value_str = str(value) if isinstance(value, bool): # Display boolean values as the C++ flag library does: no caps. value_str = value_str.lower() outfile.write('%s<%s>%s</%s>\n' % (indent, name, _MakeXMLSafe(value_str), name)) class Flag: """Information about a command-line flag. 'Flag' objects define the following fields: .name - the name for this flag .default - the default value for this flag .default_as_str - default value as repr'd string, e.g., "'true'" (or None) .value - the most recent parsed value of this flag; set by Parse() .help - a help string or None if no help is available .short_name - the single letter alias for this flag (or None) .boolean - if 'true', this flag does not accept arguments .present - true if this flag was parsed from command line flags. .parser - an ArgumentParser object .serializer - an ArgumentSerializer object .allow_override - the flag may be redefined without raising an error The only public method of a 'Flag' object is Parse(), but it is typically only called by a 'FlagValues' object. The Parse() method is a thin wrapper around the 'ArgumentParser' Parse() method. The parsed value is saved in .value, and the .present attribute is updated. If this flag was already present, a FlagsError is raised. Parse() is also called during __init__ to parse the default value and initialize the .value attribute. This enables other python modules to safely use flags even if the __main__ module neglects to parse the command line arguments. The .present attribute is cleared after __init__ parsing. If the default value is set to None, then the __init__ parsing step is skipped and the .value attribute is initialized to None. Note: The default value is also presented to the user in the help string, so it is important that it be a legal value for this flag. """ def __init__(self, parser, serializer, name, default, help_string, short_name=None, boolean=0, allow_override=0): self.name = name if not help_string: help_string = '(no help available)' self.help = help_string self.short_name = short_name self.boolean = boolean self.present = 0 self.parser = parser self.serializer = serializer self.allow_override = allow_override self.value = None self.validators = [] self.SetDefault(default) def __GetParsedValueAsString(self, value): if value is None: return None if self.serializer: return repr(self.serializer.Serialize(value)) if self.boolean: if value: return repr('true') else: return repr('false') return repr(str(value)) def Parse(self, argument): try: self.value = self.parser.Parse(argument) except ValueError, e: # recast ValueError as IllegalFlagValue raise IllegalFlagValue("flag --%s=%s: %s" % (self.name, argument, e)) self.present += 1 def Unparse(self): if self.default is None: self.value = None else: self.Parse(self.default) self.present = 0 def Serialize(self): if self.value is None: return '' if self.boolean: if self.value: return "--%s" % self.name else: return "--no%s" % self.name else: if not self.serializer: raise FlagsError("Serializer not present for flag %s" % self.name) return "--%s=%s" % (self.name, self.serializer.Serialize(self.value)) def SetDefault(self, value): """Changes the default value (and current value too) for this Flag.""" # We can't allow a None override because it may end up not being # passed to C++ code when we're overriding C++ flags. So we # cowardly bail out until someone fixes the semantics of trying to # pass None to a C++ flag. See swig_flags.Init() for details on # this behavior. # TODO(olexiy): Users can directly call this method, bypassing all flags # validators (we don't have FlagValues here, so we can not check # validators). # The simplest solution I see is to make this method private. # Another approach would be to store reference to the corresponding # FlagValues with each flag, but this seems to be an overkill. if value is None and self.allow_override: raise DuplicateFlagCannotPropagateNoneToSwig(self.name) self.default = value self.Unparse() self.default_as_str = self.__GetParsedValueAsString(self.value) def Type(self): """Returns: a string that describes the type of this Flag.""" # NOTE: we use strings, and not the types.*Type constants because # our flags can have more exotic types, e.g., 'comma separated list # of strings', 'whitespace separated list of strings', etc. return self.parser.Type() def WriteInfoInXMLFormat(self, outfile, module_name, is_key=False, indent=''): """Writes common info about this flag, in XML format. This is information that is relevant to all flags (e.g., name, meaning, etc.). If you defined a flag that has some other pieces of info, then please override _WriteCustomInfoInXMLFormat. Please do NOT override this method. Args: outfile: File object we write to. module_name: A string, the name of the module that defines this flag. is_key: A boolean, True iff this flag is key for main module. indent: A string that is prepended to each generated line. """ outfile.write(indent + '<flag>\n') inner_indent = indent + ' ' if is_key: _WriteSimpleXMLElement(outfile, 'key', 'yes', inner_indent) _WriteSimpleXMLElement(outfile, 'file', module_name, inner_indent) # Print flag features that are relevant for all flags. _WriteSimpleXMLElement(outfile, 'name', self.name, inner_indent) if self.short_name: _WriteSimpleXMLElement(outfile, 'short_name', self.short_name, inner_indent) if self.help: _WriteSimpleXMLElement(outfile, 'meaning', self.help, inner_indent) # The default flag value can either be represented as a string like on the # command line, or as a Python object. We serialize this value in the # latter case in order to remain consistent. if self.serializer and not isinstance(self.default, str): default_serialized = self.serializer.Serialize(self.default) else: default_serialized = self.default _WriteSimpleXMLElement(outfile, 'default', default_serialized, inner_indent) _WriteSimpleXMLElement(outfile, 'current', self.value, inner_indent) _WriteSimpleXMLElement(outfile, 'type', self.Type(), inner_indent) # Print extra flag features this flag may have. self._WriteCustomInfoInXMLFormat(outfile, inner_indent) outfile.write(indent + '</flag>\n') def _WriteCustomInfoInXMLFormat(self, outfile, indent): """Writes extra info about this flag, in XML format. "Extra" means "not already printed by WriteInfoInXMLFormat above." Args: outfile: File object we write to. indent: A string that is prepended to each generated line. """ # Usually, the parser knows the extra details about the flag, so # we just forward the call to it. self.parser.WriteCustomInfoInXMLFormat(outfile, indent) # End of Flag definition class _ArgumentParserCache(type): """Metaclass used to cache and share argument parsers among flags.""" _instances = {} def __call__(mcs, *args, **kwargs): """Returns an instance of the argument parser cls. This method overrides behavior of the __new__ methods in all subclasses of ArgumentParser (inclusive). If an instance for mcs with the same set of arguments exists, this instance is returned, otherwise a new instance is created. If any keyword arguments are defined, or the values in args are not hashable, this method always returns a new instance of cls. Args: args: Positional initializer arguments. kwargs: Initializer keyword arguments. Returns: An instance of cls, shared or new. """ if kwargs: return type.__call__(mcs, *args, **kwargs) else: instances = mcs._instances key = (mcs,) + tuple(args) try: return instances[key] except KeyError: # No cache entry for key exists, create a new one. return instances.setdefault(key, type.__call__(mcs, *args)) except TypeError: # An object in args cannot be hashed, always return # a new instance. return type.__call__(mcs, *args) class ArgumentParser(object): """Base class used to parse and convert arguments. The Parse() method checks to make sure that the string argument is a legal value and convert it to a native type. If the value cannot be converted, it should throw a 'ValueError' exception with a human readable explanation of why the value is illegal. Subclasses should also define a syntactic_help string which may be presented to the user to describe the form of the legal values. Argument parser classes must be stateless, since instances are cached and shared between flags. Initializer arguments are allowed, but all member variables must be derived from initializer arguments only. """ __metaclass__ = _ArgumentParserCache syntactic_help = "" def Parse(self, argument): """Default implementation: always returns its argument unmodified.""" return argument def Type(self): return 'string' def WriteCustomInfoInXMLFormat(self, outfile, indent): pass class ArgumentSerializer: """Base class for generating string representations of a flag value.""" def Serialize(self, value): return str(value) class ListSerializer(ArgumentSerializer): def __init__(self, list_sep): self.list_sep = list_sep def Serialize(self, value): return self.list_sep.join([str(x) for x in value]) # Flags validators def RegisterValidator(flag_name, checker, message='Flag validation failed', flag_values=FLAGS): """Adds a constraint, which will be enforced during program execution. The constraint is validated when flags are initially parsed, and after each change of the corresponding flag's value. Args: flag_name: string, name of the flag to be checked. checker: method to validate the flag. input - value of the corresponding flag (string, boolean, etc. This value will be passed to checker by the library). See file's docstring for examples. output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise gflags_validators.Error(desired_error_message). message: error text to be shown to the user if checker returns False. If checker raises gflags_validators.Error, message from the raised Error will be shown. flag_values: FlagValues Raises: AttributeError: if flag_name is not registered as a valid flag name. """ flag_values.AddValidator(gflags_validators.SimpleValidator(flag_name, checker, message)) def MarkFlagAsRequired(flag_name, flag_values=FLAGS): """Ensure that flag is not None during program execution. Registers a flag validator, which will follow usual validator rules. Args: flag_name: string, name of the flag flag_values: FlagValues Raises: AttributeError: if flag_name is not registered as a valid flag name. """ RegisterValidator(flag_name, lambda value: value is not None, message='Flag --%s must be specified.' % flag_name, flag_values=flag_values) def _RegisterBoundsValidatorIfNeeded(parser, name, flag_values): """Enforce lower and upper bounds for numeric flags. Args: parser: NumericParser (either FloatParser or IntegerParser). Provides lower and upper bounds, and help text to display. name: string, name of the flag flag_values: FlagValues """ if parser.lower_bound is not None or parser.upper_bound is not None: def Checker(value): if value is not None and parser.IsOutsideBounds(value): message = '%s is not %s' % (value, parser.syntactic_help) raise gflags_validators.Error(message) return True RegisterValidator(name, Checker, flag_values=flag_values) # The DEFINE functions are explained in mode details in the module doc string. def DEFINE(parser, name, default, help, flag_values=FLAGS, serializer=None, **args): """Registers a generic Flag object. NOTE: in the docstrings of all DEFINE* functions, "registers" is short for "creates a new flag and registers it". Auxiliary function: clients should use the specialized DEFINE_<type> function instead. Args: parser: ArgumentParser that is used to parse the flag arguments. name: A string, the flag name. default: The default value of the flag. help: A help string. flag_values: FlagValues object the flag will be registered with. serializer: ArgumentSerializer that serializes the flag value. args: Dictionary with extra keyword args that are passes to the Flag __init__. """ DEFINE_flag(Flag(parser, serializer, name, default, help, **args), flag_values) def DEFINE_flag(flag, flag_values=FLAGS): """Registers a 'Flag' object with a 'FlagValues' object. By default, the global FLAGS 'FlagValue' object is used. Typical users will use one of the more specialized DEFINE_xxx functions, such as DEFINE_string or DEFINE_integer. But developers who need to create Flag objects themselves should use this function to register their flags. """ # copying the reference to flag_values prevents pychecker warnings fv = flag_values fv[flag.name] = flag # Tell flag_values who's defining the flag. if isinstance(flag_values, FlagValues): # Regarding the above isinstance test: some users pass funny # values of flag_values (e.g., {}) in order to avoid the flag # registration (in the past, there used to be a flag_values == # FLAGS test here) and redefine flags with the same name (e.g., # debug). To avoid breaking their code, we perform the # registration only if flag_values is a real FlagValues object. flag_values._RegisterFlagByModule(_GetCallingModule(), flag) def _InternalDeclareKeyFlags(flag_names, flag_values=FLAGS, key_flag_values=None): """Declares a flag as key for the calling module. Internal function. User code should call DECLARE_key_flag or ADOPT_module_key_flags instead. Args: flag_names: A list of strings that are names of already-registered Flag objects. flag_values: A FlagValues object that the flags listed in flag_names have registered with (the value of the flag_values argument from the DEFINE_* calls that defined those flags). This should almost never need to be overridden. key_flag_values: A FlagValues object that (among possibly many other things) keeps track of the key flags for each module. Default None means "same as flag_values". This should almost never need to be overridden. Raises: UnrecognizedFlagError: when we refer to a flag that was not defined yet. """ key_flag_values = key_flag_values or flag_values module = _GetCallingModule() for flag_name in flag_names: if flag_name not in flag_values: raise UnrecognizedFlagError(flag_name) flag = flag_values.FlagDict()[flag_name] key_flag_values._RegisterKeyFlagForModule(module, flag) def DECLARE_key_flag(flag_name, flag_values=FLAGS): """Declares one flag as key to the current module. Key flags are flags that are deemed really important for a module. They are important when listing help messages; e.g., if the --helpshort command-line flag is used, then only the key flags of the main module are listed (instead of all flags, as in the case of --help). Sample usage: flags.DECLARED_key_flag('flag_1') Args: flag_name: A string, the name of an already declared flag. (Redeclaring flags as key, including flags implicitly key because they were declared in this module, is a no-op.) flag_values: A FlagValues object. This should almost never need to be overridden. """ if flag_name in _SPECIAL_FLAGS: # Take care of the special flags, e.g., --flagfile, --undefok. # These flags are defined in _SPECIAL_FLAGS, and are treated # specially during flag parsing, taking precedence over the # user-defined flags. _InternalDeclareKeyFlags([flag_name], flag_values=_SPECIAL_FLAGS, key_flag_values=flag_values) return _InternalDeclareKeyFlags([flag_name], flag_values=flag_values) def ADOPT_module_key_flags(module, flag_values=FLAGS): """Declares that all flags key to a module are key to the current module. Args: module: A module object. flag_values: A FlagValues object. This should almost never need to be overridden. Raises: FlagsError: When given an argument that is a module name (a string), instead of a module object. """ # NOTE(salcianu): an even better test would be if not # isinstance(module, types.ModuleType) but I didn't want to import # types for such a tiny use. if isinstance(module, str): raise FlagsError('Received module name %s; expected a module object.' % module) _InternalDeclareKeyFlags( [f.name for f in flag_values._GetKeyFlagsForModule(module.__name__)], flag_values=flag_values) # If module is this flag module, take _SPECIAL_FLAGS into account. if module == _GetThisModuleObjectAndName()[0]: _InternalDeclareKeyFlags( # As we associate flags with _GetCallingModule(), the special # flags defined in this module are incorrectly registered with # a different module. So, we can't use _GetKeyFlagsForModule. # Instead, we take all flags from _SPECIAL_FLAGS (a private # FlagValues, where no other module should register flags). [f.name for f in _SPECIAL_FLAGS.FlagDict().values()], flag_values=_SPECIAL_FLAGS, key_flag_values=flag_values) # # STRING FLAGS # def DEFINE_string(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value can be any string.""" parser = ArgumentParser() serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) # # BOOLEAN FLAGS # # and the special HELP flags. class BooleanParser(ArgumentParser): """Parser of boolean values.""" def Convert(self, argument): """Converts the argument to a boolean; raise ValueError on errors.""" if type(argument) == str: if argument.lower() in ['true', 't', '1']: return True elif argument.lower() in ['false', 'f', '0']: return False bool_argument = bool(argument) if argument == bool_argument: # The argument is a valid boolean (True, False, 0, or 1), and not just # something that always converts to bool (list, string, int, etc.). return bool_argument raise ValueError('Non-boolean argument to boolean flag', argument) def Parse(self, argument): val = self.Convert(argument) return val def Type(self): return 'bool' class BooleanFlag(Flag): """Basic boolean flag. Boolean flags do not take any arguments, and their value is either True (1) or False (0). The false value is specified on the command line by prepending the word 'no' to either the long or the short flag name. For example, if a Boolean flag was created whose long name was 'update' and whose short name was 'x', then this flag could be explicitly unset through either --noupdate or --nox. """ def __init__(self, name, default, help, short_name=None, **args): p = BooleanParser() Flag.__init__(self, p, None, name, default, help, short_name, 1, **args) if not self.help: self.help = "a boolean value" def DEFINE_boolean(name, default, help, flag_values=FLAGS, **args): """Registers a boolean flag. Such a boolean flag does not take an argument. If a user wants to specify a false value explicitly, the long option beginning with 'no' must be used: i.e. --noflag This flag will have a value of None, True or False. None is possible if default=None and the user does not specify the flag on the command line. """ DEFINE_flag(BooleanFlag(name, default, help, **args), flag_values) # Match C++ API to unconfuse C++ people. DEFINE_bool = DEFINE_boolean class HelpFlag(BooleanFlag): """ HelpFlag is a special boolean flag that prints usage information and raises a SystemExit exception if it is ever found in the command line arguments. Note this is called with allow_override=1, so other apps can define their own --help flag, replacing this one, if they want. """ def __init__(self): BooleanFlag.__init__(self, "help", 0, "show this help", short_name="?", allow_override=1) def Parse(self, arg): if arg: doc = sys.modules["__main__"].__doc__ flags = str(FLAGS) print doc or ("\nUSAGE: %s [flags]\n" % sys.argv[0]) if flags: print "flags:" print flags sys.exit(1) class HelpXMLFlag(BooleanFlag): """Similar to HelpFlag, but generates output in XML format.""" def __init__(self): BooleanFlag.__init__(self, 'helpxml', False, 'like --help, but generates XML output', allow_override=1) def Parse(self, arg): if arg: FLAGS.WriteHelpInXMLFormat(sys.stdout) sys.exit(1) class HelpshortFlag(BooleanFlag): """ HelpshortFlag is a special boolean flag that prints usage information for the "main" module, and rasies a SystemExit exception if it is ever found in the command line arguments. Note this is called with allow_override=1, so other apps can define their own --helpshort flag, replacing this one, if they want. """ def __init__(self): BooleanFlag.__init__(self, "helpshort", 0, "show usage only for this module", allow_override=1) def Parse(self, arg): if arg: doc = sys.modules["__main__"].__doc__ flags = FLAGS.MainModuleHelp() print doc or ("\nUSAGE: %s [flags]\n" % sys.argv[0]) if flags: print "flags:" print flags sys.exit(1) # # Numeric parser - base class for Integer and Float parsers # class NumericParser(ArgumentParser): """Parser of numeric values. Parsed value may be bounded to a given upper and lower bound. """ def IsOutsideBounds(self, val): return ((self.lower_bound is not None and val < self.lower_bound) or (self.upper_bound is not None and val > self.upper_bound)) def Parse(self, argument): val = self.Convert(argument) if self.IsOutsideBounds(val): raise ValueError("%s is not %s" % (val, self.syntactic_help)) return val def WriteCustomInfoInXMLFormat(self, outfile, indent): if self.lower_bound is not None: _WriteSimpleXMLElement(outfile, 'lower_bound', self.lower_bound, indent) if self.upper_bound is not None: _WriteSimpleXMLElement(outfile, 'upper_bound', self.upper_bound, indent) def Convert(self, argument): """Default implementation: always returns its argument unmodified.""" return argument # End of Numeric Parser # # FLOAT FLAGS # class FloatParser(NumericParser): """Parser of floating point values. Parsed value may be bounded to a given upper and lower bound. """ number_article = "a" number_name = "number" syntactic_help = " ".join((number_article, number_name)) def __init__(self, lower_bound=None, upper_bound=None): super(FloatParser, self).__init__() self.lower_bound = lower_bound self.upper_bound = upper_bound sh = self.syntactic_help if lower_bound is not None and upper_bound is not None: sh = ("%s in the range [%s, %s]" % (sh, lower_bound, upper_bound)) elif lower_bound == 0: sh = "a non-negative %s" % self.number_name elif upper_bound == 0: sh = "a non-positive %s" % self.number_name elif upper_bound is not None: sh = "%s <= %s" % (self.number_name, upper_bound) elif lower_bound is not None: sh = "%s >= %s" % (self.number_name, lower_bound) self.syntactic_help = sh def Convert(self, argument): """Converts argument to a float; raises ValueError on errors.""" return float(argument) def Type(self): return 'float' # End of FloatParser def DEFINE_float(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value must be a float. If lower_bound or upper_bound are set, then this flag must be within the given range. """ parser = FloatParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) _RegisterBoundsValidatorIfNeeded(parser, name, flag_values=flag_values) # # INTEGER FLAGS # class IntegerParser(NumericParser): """Parser of an integer value. Parsed value may be bounded to a given upper and lower bound. """ number_article = "an" number_name = "integer" syntactic_help = " ".join((number_article, number_name)) def __init__(self, lower_bound=None, upper_bound=None): super(IntegerParser, self).__init__() self.lower_bound = lower_bound self.upper_bound = upper_bound sh = self.syntactic_help if lower_bound is not None and upper_bound is not None: sh = ("%s in the range [%s, %s]" % (sh, lower_bound, upper_bound)) elif lower_bound == 1: sh = "a positive %s" % self.number_name elif upper_bound == -1: sh = "a negative %s" % self.number_name elif lower_bound == 0: sh = "a non-negative %s" % self.number_name elif upper_bound == 0: sh = "a non-positive %s" % self.number_name elif upper_bound is not None: sh = "%s <= %s" % (self.number_name, upper_bound) elif lower_bound is not None: sh = "%s >= %s" % (self.number_name, lower_bound) self.syntactic_help = sh def Convert(self, argument): __pychecker__ = 'no-returnvalues' if type(argument) == str: base = 10 if len(argument) > 2 and argument[0] == "0" and argument[1] == "x": base = 16 try: return int(argument, base) # ValueError is thrown when argument is a string, and overflows an int. except ValueError: return long(argument, base) else: try: return int(argument) # OverflowError is thrown when argument is numeric, and overflows an int. except OverflowError: return long(argument) def Type(self): return 'int' def DEFINE_integer(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value must be an integer. If lower_bound, or upper_bound are set, then this flag must be within the given range. """ parser = IntegerParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) _RegisterBoundsValidatorIfNeeded(parser, name, flag_values=flag_values) # # ENUM FLAGS # class EnumParser(ArgumentParser): """Parser of a string enum value (a string value from a given set). If enum_values (see below) is not specified, any string is allowed. """ def __init__(self, enum_values=None): super(EnumParser, self).__init__() self.enum_values = enum_values def Parse(self, argument): if self.enum_values and argument not in self.enum_values: raise ValueError("value should be one of <%s>" % "|".join(self.enum_values)) return argument def Type(self): return 'string enum' class EnumFlag(Flag): """Basic enum flag; its value can be any string from list of enum_values.""" def __init__(self, name, default, help, enum_values=None, short_name=None, **args): enum_values = enum_values or [] p = EnumParser(enum_values) g = ArgumentSerializer() Flag.__init__(self, p, g, name, default, help, short_name, **args) if not self.help: self.help = "an enum string" self.help = "<%s>: %s" % ("|".join(enum_values), self.help) def _WriteCustomInfoInXMLFormat(self, outfile, indent): for enum_value in self.parser.enum_values: _WriteSimpleXMLElement(outfile, 'enum_value', enum_value, indent) def DEFINE_enum(name, default, enum_values, help, flag_values=FLAGS, **args): """Registers a flag whose value can be any string from enum_values.""" DEFINE_flag(EnumFlag(name, default, help, enum_values, ** args), flag_values) # # LIST FLAGS # class BaseListParser(ArgumentParser): """Base class for a parser of lists of strings. To extend, inherit from this class; from the subclass __init__, call BaseListParser.__init__(self, token, name) where token is a character used to tokenize, and name is a description of the separator. """ def __init__(self, token=None, name=None): assert name super(BaseListParser, self).__init__() self._token = token self._name = name self.syntactic_help = "a %s separated list" % self._name def Parse(self, argument): if isinstance(argument, list): return argument elif argument == '': return [] else: return [s.strip() for s in argument.split(self._token)] def Type(self): return '%s separated list of strings' % self._name class ListParser(BaseListParser): """Parser for a comma-separated list of strings.""" def __init__(self): BaseListParser.__init__(self, ',', 'comma') def WriteCustomInfoInXMLFormat(self, outfile, indent): BaseListParser.WriteCustomInfoInXMLFormat(self, outfile, indent) _WriteSimpleXMLElement(outfile, 'list_separator', repr(','), indent) class WhitespaceSeparatedListParser(BaseListParser): """Parser for a whitespace-separated list of strings.""" def __init__(self): BaseListParser.__init__(self, None, 'whitespace') def WriteCustomInfoInXMLFormat(self, outfile, indent): BaseListParser.WriteCustomInfoInXMLFormat(self, outfile, indent) separators = list(string.whitespace) separators.sort() for ws_char in string.whitespace: _WriteSimpleXMLElement(outfile, 'list_separator', repr(ws_char), indent) def DEFINE_list(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value is a comma-separated list of strings.""" parser = ListParser() serializer = ListSerializer(',') DEFINE(parser, name, default, help, flag_values, serializer, **args) def DEFINE_spaceseplist(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value is a whitespace-separated list of strings. Any whitespace can be used as a separator. """ parser = WhitespaceSeparatedListParser() serializer = ListSerializer(' ') DEFINE(parser, name, default, help, flag_values, serializer, **args) # # MULTI FLAGS # class MultiFlag(Flag): """A flag that can appear multiple time on the command-line. The value of such a flag is a list that contains the individual values from all the appearances of that flag on the command-line. See the __doc__ for Flag for most behavior of this class. Only differences in behavior are described here: * The default value may be either a single value or a list of values. A single value is interpreted as the [value] singleton list. * The value of the flag is always a list, even if the option was only supplied once, and even if the default value is a single value """ def __init__(self, *args, **kwargs): Flag.__init__(self, *args, **kwargs) self.help += ';\n repeat this option to specify a list of values' def Parse(self, arguments): """Parses one or more arguments with the installed parser. Args: arguments: a single argument or a list of arguments (typically a list of default values); a single argument is converted internally into a list containing one item. """ if not isinstance(arguments, list): # Default value may be a list of values. Most other arguments # will not be, so convert them into a single-item list to make # processing simpler below. arguments = [arguments] if self.present: # keep a backup reference to list of previously supplied option values values = self.value else: # "erase" the defaults with an empty list values = [] for item in arguments: # have Flag superclass parse argument, overwriting self.value reference Flag.Parse(self, item) # also increments self.present values.append(self.value) # put list of option values back in the 'value' attribute self.value = values def Serialize(self): if not self.serializer: raise FlagsError("Serializer not present for flag %s" % self.name) if self.value is None: return '' s = '' multi_value = self.value for self.value in multi_value: if s: s += ' ' s += Flag.Serialize(self) self.value = multi_value return s def Type(self): return 'multi ' + self.parser.Type() def DEFINE_multi(parser, serializer, name, default, help, flag_values=FLAGS, **args): """Registers a generic MultiFlag that parses its args with a given parser. Auxiliary function. Normal users should NOT use it directly. Developers who need to create their own 'Parser' classes for options which can appear multiple times can call this module function to register their flags. """ DEFINE_flag(MultiFlag(parser, serializer, name, default, help, **args), flag_values) def DEFINE_multistring(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value can be a list of any strings. Use the flag on the command line multiple times to place multiple string values into the list. The 'default' may be a single string (which will be converted into a single-element list) or a list of strings. """ parser = ArgumentParser() serializer = ArgumentSerializer() DEFINE_multi(parser, serializer, name, default, help, flag_values, **args) def DEFINE_multi_int(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value can be a list of arbitrary integers. Use the flag on the command line multiple times to place multiple integer values into the list. The 'default' may be a single integer (which will be converted into a single-element list) or a list of integers. """ parser = IntegerParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE_multi(parser, serializer, name, default, help, flag_values, **args) # Now register the flags that we want to exist in all applications. # These are all defined with allow_override=1, so user-apps can use # these flagnames for their own purposes, if they want. DEFINE_flag(HelpFlag()) DEFINE_flag(HelpshortFlag()) DEFINE_flag(HelpXMLFlag()) # Define special flags here so that help may be generated for them. # NOTE: Please do NOT use _SPECIAL_FLAGS from outside this module. _SPECIAL_FLAGS = FlagValues() DEFINE_string( 'flagfile', "", "Insert flag definitions from the given file into the command line.", _SPECIAL_FLAGS) DEFINE_string( 'undefok', "", "comma-separated list of flag names that it is okay to specify " "on the command line even if the program does not define a flag " "with that name. IMPORTANT: flags in this list that have " "arguments MUST use the --flag=value format.", _SPECIAL_FLAGS)
Python
#!/usr/bin/env python # Copyright (c) 2010, Google Inc. # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. """Module to enforce different constraints on flags. A validator represents an invariant, enforced over a one or more flags. See 'FLAGS VALIDATORS' in flags.py's docstring for a usage manual. """ __author__ = 'olexiy@google.com (Olexiy Oryeshko)' class Error(Exception): """Thrown If validator constraint is not satisfied.""" class Validator(object): """Base class for flags validators. Users should NOT overload these classes, and use flags.Register... methods instead. """ # Used to assign each validator an unique insertion_index validators_count = 0 def __init__(self, checker, message): """Constructor to create all validators. Args: checker: function to verify the constraint. Input of this method varies, see SimpleValidator and DictionaryValidator for a detailed description. message: string, error message to be shown to the user """ self.checker = checker self.message = message Validator.validators_count += 1 # Used to assert validators in the order they were registered (CL/18694236) self.insertion_index = Validator.validators_count def Verify(self, flag_values): """Verify that constraint is satisfied. flags library calls this method to verify Validator's constraint. Args: flag_values: flags.FlagValues, containing all flags Raises: Error: if constraint is not satisfied. """ param = self._GetInputToCheckerFunction(flag_values) if not self.checker(param): raise Error(self.message) def GetFlagsNames(self): """Return the names of the flags checked by this validator. Returns: [string], names of the flags """ raise NotImplementedError('This method should be overloaded') def PrintFlagsWithValues(self, flag_values): raise NotImplementedError('This method should be overloaded') def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues, containing all flags. Returns: Return type depends on the specific validator. """ raise NotImplementedError('This method should be overloaded') class SimpleValidator(Validator): """Validator behind RegisterValidator() method. Validates that a single flag passes its checker function. The checker function takes the flag value and returns True (if value looks fine) or, if flag value is not valid, either returns False or raises an Exception.""" def __init__(self, flag_name, checker, message): """Constructor. Args: flag_name: string, name of the flag. checker: function to verify the validator. input - value of the corresponding flag (string, boolean, etc). output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise Error. message: string, error message to be shown to the user if validator's condition is not satisfied """ super(SimpleValidator, self).__init__(checker, message) self.flag_name = flag_name def GetFlagsNames(self): return [self.flag_name] def PrintFlagsWithValues(self, flag_values): return 'flag --%s=%s' % (self.flag_name, flag_values[self.flag_name].value) def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues Returns: value of the corresponding flag. """ return flag_values[self.flag_name].value class DictionaryValidator(Validator): """Validator behind RegisterDictionaryValidator method. Validates that flag values pass their common checker function. The checker function takes flag values and returns True (if values look fine) or, if values are not valid, either returns False or raises an Exception. """ def __init__(self, flag_names, checker, message): """Constructor. Args: flag_names: [string], containing names of the flags used by checker. checker: function to verify the validator. input - dictionary, with keys() being flag_names, and value for each key being the value of the corresponding flag (string, boolean, etc). output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise Error. message: string, error message to be shown to the user if validator's condition is not satisfied """ super(DictionaryValidator, self).__init__(checker, message) self.flag_names = flag_names def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues Returns: dictionary, with keys() being self.lag_names, and value for each key being the value of the corresponding flag (string, boolean, etc). """ return dict([key, flag_values[key].value] for key in self.flag_names) def PrintFlagsWithValues(self, flag_values): prefix = 'flags ' flags_with_values = [] for key in self.flag_names: flags_with_values.append('%s=%s' % (key, flag_values[key].value)) return prefix + ', '.join(flags_with_values) def GetFlagsNames(self): return self.flag_names
Python
#!/usr/bin/env python # Copyright (c) 2007, Google Inc. # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. # # --- # Author: Chad Lester # Design and style contributions by: # Amit Patel, Bogdan Cocosel, Daniel Dulitz, Eric Tiedemann, # Eric Veach, Laurence Gonsalves, Matthew Springer # Code reorganized a bit by Craig Silverstein """This module is used to define and parse command line flags. This module defines a *distributed* flag-definition policy: rather than an application having to define all flags in or near main(), each python module defines flags that are useful to it. When one python module imports another, it gains access to the other's flags. (This is implemented by having all modules share a common, global registry object containing all the flag information.) Flags are defined through the use of one of the DEFINE_xxx functions. The specific function used determines how the flag is parsed, checked, and optionally type-converted, when it's seen on the command line. IMPLEMENTATION: DEFINE_* creates a 'Flag' object and registers it with a 'FlagValues' object (typically the global FlagValues FLAGS, defined here). The 'FlagValues' object can scan the command line arguments and pass flag arguments to the corresponding 'Flag' objects for value-checking and type conversion. The converted flag values are available as attributes of the 'FlagValues' object. Code can access the flag through a FlagValues object, for instance gflags.FLAGS.myflag. Typically, the __main__ module passes the command line arguments to gflags.FLAGS for parsing. At bottom, this module calls getopt(), so getopt functionality is supported, including short- and long-style flags, and the use of -- to terminate flags. Methods defined by the flag module will throw 'FlagsError' exceptions. The exception argument will be a human-readable string. FLAG TYPES: This is a list of the DEFINE_*'s that you can do. All flags take a name, default value, help-string, and optional 'short' name (one-letter name). Some flags have other arguments, which are described with the flag. DEFINE_string: takes any input, and interprets it as a string. DEFINE_bool or DEFINE_boolean: typically does not take an argument: say --myflag to set FLAGS.myflag to true, or --nomyflag to set FLAGS.myflag to false. Alternately, you can say --myflag=true or --myflag=t or --myflag=1 or --myflag=false or --myflag=f or --myflag=0 DEFINE_float: takes an input and interprets it as a floating point number. Takes optional args lower_bound and upper_bound; if the number specified on the command line is out of range, it will raise a FlagError. DEFINE_integer: takes an input and interprets it as an integer. Takes optional args lower_bound and upper_bound as for floats. DEFINE_enum: takes a list of strings which represents legal values. If the command-line value is not in this list, raise a flag error. Otherwise, assign to FLAGS.flag as a string. DEFINE_list: Takes a comma-separated list of strings on the commandline. Stores them in a python list object. DEFINE_spaceseplist: Takes a space-separated list of strings on the commandline. Stores them in a python list object. Example: --myspacesepflag "foo bar baz" DEFINE_multistring: The same as DEFINE_string, except the flag can be specified more than once on the commandline. The result is a python list object (list of strings), even if the flag is only on the command line once. DEFINE_multi_int: The same as DEFINE_integer, except the flag can be specified more than once on the commandline. The result is a python list object (list of ints), even if the flag is only on the command line once. SPECIAL FLAGS: There are a few flags that have special meaning: --help prints a list of all the flags in a human-readable fashion --helpshort prints a list of all key flags (see below). --helpxml prints a list of all flags, in XML format. DO NOT parse the output of --help and --helpshort. Instead, parse the output of --helpxml. For more info, see "OUTPUT FOR --helpxml" below. --flagfile=foo read flags from file foo. --undefok=f1,f2 ignore unrecognized option errors for f1,f2. For boolean flags, you should use --undefok=boolflag, and --boolflag and --noboolflag will be accepted. Do not use --undefok=noboolflag. -- as in getopt(), terminates flag-processing FLAGS VALIDATORS: If your program: - requires flag X to be specified - needs flag Y to match a regular expression - or requires any more general constraint to be satisfied then validators are for you! Each validator represents a constraint over one flag, which is enforced starting from the initial parsing of the flags and until the program terminates. Also, lower_bound and upper_bound for numerical flags are enforced using flag validators. Howto: If you want to enforce a constraint over one flag, use flags.RegisterValidator(flag_name, checker, message='Flag validation failed', flag_values=FLAGS) After flag values are initially parsed, and after any change to the specified flag, method checker(flag_value) will be executed. If constraint is not satisfied, an IllegalFlagValue exception will be raised. See RegisterValidator's docstring for a detailed explanation on how to construct your own checker. EXAMPLE USAGE: FLAGS = flags.FLAGS flags.DEFINE_integer('my_version', 0, 'Version number.') flags.DEFINE_string('filename', None, 'Input file name', short_name='f') flags.RegisterValidator('my_version', lambda value: value % 2 == 0, message='--my_version must be divisible by 2') flags.MarkFlagAsRequired('filename') NOTE ON --flagfile: Flags may be loaded from text files in addition to being specified on the commandline. Any flags you don't feel like typing, throw them in a file, one flag per line, for instance: --myflag=myvalue --nomyboolean_flag You then specify your file with the special flag '--flagfile=somefile'. You CAN recursively nest flagfile= tokens OR use multiple files on the command line. Lines beginning with a single hash '#' or a double slash '//' are comments in your flagfile. Any flagfile=<file> will be interpreted as having a relative path from the current working directory rather than from the place the file was included from: myPythonScript.py --flagfile=config/somefile.cfg If somefile.cfg includes further --flagfile= directives, these will be referenced relative to the original CWD, not from the directory the including flagfile was found in! The caveat applies to people who are including a series of nested files in a different dir than they are executing out of. Relative path names are always from CWD, not from the directory of the parent include flagfile. We do now support '~' expanded directory names. Absolute path names ALWAYS work! EXAMPLE USAGE: import gflags FLAGS = gflags.FLAGS # Flag names are globally defined! So in general, we need to be # careful to pick names that are unlikely to be used by other libraries. # If there is a conflict, we'll get an error at import time. gflags.DEFINE_string('name', 'Mr. President', 'your name') gflags.DEFINE_integer('age', None, 'your age in years', lower_bound=0) gflags.DEFINE_boolean('debug', False, 'produces debugging output') gflags.DEFINE_enum('gender', 'male', ['male', 'female'], 'your gender') def main(argv): try: argv = FLAGS(argv) # parse flags except gflags.FlagsError, e: print '%s\\nUsage: %s ARGS\\n%s' % (e, sys.argv[0], FLAGS) sys.exit(1) if FLAGS.debug: print 'non-flag arguments:', argv print 'Happy Birthday', FLAGS.name if FLAGS.age is not None: print 'You are a %s, who is %d years old' % (FLAGS.gender, FLAGS.age) if __name__ == '__main__': main(sys.argv) KEY FLAGS: As we already explained, each module gains access to all flags defined by all the other modules it transitively imports. In the case of non-trivial scripts, this means a lot of flags ... For documentation purposes, it is good to identify the flags that are key (i.e., really important) to a module. Clearly, the concept of "key flag" is a subjective one. When trying to determine whether a flag is key to a module or not, assume that you are trying to explain your module to a potential user: which flags would you really like to mention first? We'll describe shortly how to declare which flags are key to a module. For the moment, assume we know the set of key flags for each module. Then, if you use the app.py module, you can use the --helpshort flag to print only the help for the flags that are key to the main module, in a human-readable format. NOTE: If you need to parse the flag help, do NOT use the output of --help / --helpshort. That output is meant for human consumption, and may be changed in the future. Instead, use --helpxml; flags that are key for the main module are marked there with a <key>yes</key> element. The set of key flags for a module M is composed of: 1. Flags defined by module M by calling a DEFINE_* function. 2. Flags that module M explictly declares as key by using the function DECLARE_key_flag(<flag_name>) 3. Key flags of other modules that M specifies by using the function ADOPT_module_key_flags(<other_module>) This is a "bulk" declaration of key flags: each flag that is key for <other_module> becomes key for the current module too. Notice that if you do not use the functions described at points 2 and 3 above, then --helpshort prints information only about the flags defined by the main module of our script. In many cases, this behavior is good enough. But if you move part of the main module code (together with the related flags) into a different module, then it is nice to use DECLARE_key_flag / ADOPT_module_key_flags and make sure --helpshort lists all relevant flags (otherwise, your code refactoring may confuse your users). Note: each of DECLARE_key_flag / ADOPT_module_key_flags has its own pluses and minuses: DECLARE_key_flag is more targeted and may lead a more focused --helpshort documentation. ADOPT_module_key_flags is good for cases when an entire module is considered key to the current script. Also, it does not require updates to client scripts when a new flag is added to the module. EXAMPLE USAGE 2 (WITH KEY FLAGS): Consider an application that contains the following three files (two auxiliary modules and a main module): File libfoo.py: import gflags gflags.DEFINE_integer('num_replicas', 3, 'Number of replicas to start') gflags.DEFINE_boolean('rpc2', True, 'Turn on the usage of RPC2.') ... some code ... File libbar.py: import gflags gflags.DEFINE_string('bar_gfs_path', '/gfs/path', 'Path to the GFS files for libbar.') gflags.DEFINE_string('email_for_bar_errors', 'bar-team@google.com', 'Email address for bug reports about module libbar.') gflags.DEFINE_boolean('bar_risky_hack', False, 'Turn on an experimental and buggy optimization.') ... some code ... File myscript.py: import gflags import libfoo import libbar gflags.DEFINE_integer('num_iterations', 0, 'Number of iterations.') # Declare that all flags that are key for libfoo are # key for this module too. gflags.ADOPT_module_key_flags(libfoo) # Declare that the flag --bar_gfs_path (defined in libbar) is key # for this module. gflags.DECLARE_key_flag('bar_gfs_path') ... some code ... When myscript is invoked with the flag --helpshort, the resulted help message lists information about all the key flags for myscript: --num_iterations, --num_replicas, --rpc2, and --bar_gfs_path (in addition to the special flags --help and --helpshort). Of course, myscript uses all the flags declared by it (in this case, just --num_replicas) or by any of the modules it transitively imports (e.g., the modules libfoo, libbar). E.g., it can access the value of FLAGS.bar_risky_hack, even if --bar_risky_hack is not declared as a key flag for myscript. OUTPUT FOR --helpxml: The --helpxml flag generates output with the following structure: <?xml version="1.0"?> <AllFlags> <program>PROGRAM_BASENAME</program> <usage>MAIN_MODULE_DOCSTRING</usage> (<flag> [<key>yes</key>] <file>DECLARING_MODULE</file> <name>FLAG_NAME</name> <meaning>FLAG_HELP_MESSAGE</meaning> <default>DEFAULT_FLAG_VALUE</default> <current>CURRENT_FLAG_VALUE</current> <type>FLAG_TYPE</type> [OPTIONAL_ELEMENTS] </flag>)* </AllFlags> Notes: 1. The output is intentionally similar to the output generated by the C++ command-line flag library. The few differences are due to the Python flags that do not have a C++ equivalent (at least not yet), e.g., DEFINE_list. 2. New XML elements may be added in the future. 3. DEFAULT_FLAG_VALUE is in serialized form, i.e., the string you can pass for this flag on the command-line. E.g., for a flag defined using DEFINE_list, this field may be foo,bar, not ['foo', 'bar']. 4. CURRENT_FLAG_VALUE is produced using str(). This means that the string 'false' will be represented in the same way as the boolean False. Using repr() would have removed this ambiguity and simplified parsing, but would have broken the compatibility with the C++ command-line flags. 5. OPTIONAL_ELEMENTS describe elements relevant for certain kinds of flags: lower_bound, upper_bound (for flags that specify bounds), enum_value (for enum flags), list_separator (for flags that consist of a list of values, separated by a special token). 6. We do not provide any example here: please use --helpxml instead. """ import cgi import getopt import os import re import string import sys import gflags_validators # Are we running at least python 2.2? try: if tuple(sys.version_info[:3]) < (2,2,0): raise NotImplementedError("requires python 2.2.0 or later") except AttributeError: # a very old python, that lacks sys.version_info raise NotImplementedError("requires python 2.2.0 or later") # If we're not running at least python 2.2.1, define True, False, and bool. # Thanks, Guido, for the code. try: True, False, bool except NameError: False = 0 True = 1 def bool(x): if x: return True else: return False # Are we running under pychecker? _RUNNING_PYCHECKER = 'pychecker.python' in sys.modules def _GetCallingModule(): """Returns the name of the module that's calling into this module. We generally use this function to get the name of the module calling a DEFINE_foo... function. """ # Walk down the stack to find the first globals dict that's not ours. for depth in range(1, sys.getrecursionlimit()): if not sys._getframe(depth).f_globals is globals(): globals_for_frame = sys._getframe(depth).f_globals module_name = _GetModuleObjectAndName(globals_for_frame)[1] if module_name is not None: return module_name raise AssertionError("No module was found") def _GetThisModuleObjectAndName(): """Returns: (module object, module name) for this module.""" return _GetModuleObjectAndName(globals()) # module exceptions: class FlagsError(Exception): """The base class for all flags errors.""" pass class DuplicateFlag(FlagsError): """Raised if there is a flag naming conflict.""" pass class DuplicateFlagCannotPropagateNoneToSwig(DuplicateFlag): """Special case of DuplicateFlag -- SWIG flag value can't be set to None. This can be raised when a duplicate flag is created. Even if allow_override is True, we still abort if the new value is None, because it's currently impossible to pass None default value back to SWIG. See FlagValues.SetDefault for details. """ pass # A DuplicateFlagError conveys more information than a # DuplicateFlag. Since there are external modules that create # DuplicateFlags, the interface to DuplicateFlag shouldn't change. class DuplicateFlagError(DuplicateFlag): def __init__(self, flagname, flag_values): self.flagname = flagname message = "The flag '%s' is defined twice." % self.flagname flags_by_module = flag_values.FlagsByModuleDict() for module in flags_by_module: for flag in flags_by_module[module]: if flag.name == flagname or flag.short_name == flagname: message = message + " First from " + module + "," break message = message + " Second from " + _GetCallingModule() DuplicateFlag.__init__(self, message) class IllegalFlagValue(FlagsError): """The flag command line argument is illegal.""" pass class UnrecognizedFlag(FlagsError): """Raised if a flag is unrecognized.""" pass # An UnrecognizedFlagError conveys more information than an UnrecognizedFlag. # Since there are external modules that create DuplicateFlags, the interface to # DuplicateFlag shouldn't change. The flagvalue will be assigned the full value # of the flag and its argument, if any, allowing handling of unrecognzed flags # in an exception handler. # If flagvalue is the empty string, then this exception is an due to a # reference to a flag that was not already defined. class UnrecognizedFlagError(UnrecognizedFlag): def __init__(self, flagname, flagvalue=''): self.flagname = flagname self.flagvalue = flagvalue UnrecognizedFlag.__init__( self, "Unknown command line flag '%s'" % flagname) # Global variable used by expvar _exported_flags = {} _help_width = 80 # width of help output def GetHelpWidth(): """Returns: an integer, the width of help lines that is used in TextWrap.""" return _help_width def CutCommonSpacePrefix(text): """Removes a common space prefix from the lines of a multiline text. If the first line does not start with a space, it is left as it is and only in the remaining lines a common space prefix is being searched for. That means the first line will stay untouched. This is especially useful to turn doc strings into help texts. This is because some people prefer to have the doc comment start already after the apostrophy and then align the following lines while others have the apostrophies on a seperately line. The function also drops trailing empty lines and ignores empty lines following the initial content line while calculating the initial common whitespace. Args: text: text to work on Returns: the resulting text """ text_lines = text.splitlines() # Drop trailing empty lines while text_lines and not text_lines[-1]: text_lines = text_lines[:-1] if text_lines: # We got some content, is the first line starting with a space? if text_lines[0] and text_lines[0][0].isspace(): text_first_line = [] else: text_first_line = [text_lines.pop(0)] # Calculate length of common leading whitesppace (only over content lines) common_prefix = os.path.commonprefix([line for line in text_lines if line]) space_prefix_len = len(common_prefix) - len(common_prefix.lstrip()) # If we have a common space prefix, drop it from all lines if space_prefix_len: for index in xrange(len(text_lines)): if text_lines[index]: text_lines[index] = text_lines[index][space_prefix_len:] return '\n'.join(text_first_line + text_lines) return '' def TextWrap(text, length=None, indent='', firstline_indent=None, tabs=' '): """Wraps a given text to a maximum line length and returns it. We turn lines that only contain whitespaces into empty lines. We keep new lines and tabs (e.g., we do not treat tabs as spaces). Args: text: text to wrap length: maximum length of a line, includes indentation if this is None then use GetHelpWidth() indent: indent for all but first line firstline_indent: indent for first line; if None, fall back to indent tabs: replacement for tabs Returns: wrapped text Raises: FlagsError: if indent not shorter than length FlagsError: if firstline_indent not shorter than length """ # Get defaults where callee used None if length is None: length = GetHelpWidth() if indent is None: indent = '' if len(indent) >= length: raise FlagsError('Indent must be shorter than length') # In line we will be holding the current line which is to be started # with indent (or firstline_indent if available) and then appended # with words. if firstline_indent is None: firstline_indent = '' line = indent else: line = firstline_indent if len(firstline_indent) >= length: raise FlagsError('First iline indent must be shorter than length') # If the callee does not care about tabs we simply convert them to # spaces If callee wanted tabs to be single space then we do that # already here. if not tabs or tabs == ' ': text = text.replace('\t', ' ') else: tabs_are_whitespace = not tabs.strip() line_regex = re.compile('([ ]*)(\t*)([^ \t]+)', re.MULTILINE) # Split the text into lines and the lines with the regex above. The # resulting lines are collected in result[]. For each split we get the # spaces, the tabs and the next non white space (e.g. next word). result = [] for text_line in text.splitlines(): # Store result length so we can find out whether processing the next # line gave any new content old_result_len = len(result) # Process next line with line_regex. For optimization we do an rstrip(). # - process tabs (changes either line or word, see below) # - process word (first try to squeeze on line, then wrap or force wrap) # Spaces found on the line are ignored, they get added while wrapping as # needed. for spaces, current_tabs, word in line_regex.findall(text_line.rstrip()): # If tabs weren't converted to spaces, handle them now if current_tabs: # If the last thing we added was a space anyway then drop # it. But let's not get rid of the indentation. if (((result and line != indent) or (not result and line != firstline_indent)) and line[-1] == ' '): line = line[:-1] # Add the tabs, if that means adding whitespace, just add it at # the line, the rstrip() code while shorten the line down if # necessary if tabs_are_whitespace: line += tabs * len(current_tabs) else: # if not all tab replacement is whitespace we prepend it to the word word = tabs * len(current_tabs) + word # Handle the case where word cannot be squeezed onto current last line if len(line) + len(word) > length and len(indent) + len(word) <= length: result.append(line.rstrip()) line = indent + word word = '' # No space left on line or can we append a space? if len(line) + 1 >= length: result.append(line.rstrip()) line = indent else: line += ' ' # Add word and shorten it up to allowed line length. Restart next # line with indent and repeat, or add a space if we're done (word # finished) This deals with words that caanot fit on one line # (e.g. indent + word longer than allowed line length). while len(line) + len(word) >= length: line += word result.append(line[:length]) word = line[length:] line = indent # Default case, simply append the word and a space if word: line += word + ' ' # End of input line. If we have content we finish the line. If the # current line is just the indent but we had content in during this # original line then we need to add an emoty line. if (result and line != indent) or (not result and line != firstline_indent): result.append(line.rstrip()) elif len(result) == old_result_len: result.append('') line = indent return '\n'.join(result) def DocToHelp(doc): """Takes a __doc__ string and reformats it as help.""" # Get rid of starting and ending white space. Using lstrip() or even # strip() could drop more than maximum of first line and right space # of last line. doc = doc.strip() # Get rid of all empty lines whitespace_only_line = re.compile('^[ \t]+$', re.M) doc = whitespace_only_line.sub('', doc) # Cut out common space at line beginnings doc = CutCommonSpacePrefix(doc) # Just like this module's comment, comments tend to be aligned somehow. # In other words they all start with the same amount of white space # 1) keep double new lines # 2) keep ws after new lines if not empty line # 3) all other new lines shall be changed to a space # Solution: Match new lines between non white space and replace with space. doc = re.sub('(?<=\S)\n(?=\S)', ' ', doc, re.M) return doc def _GetModuleObjectAndName(globals_dict): """Returns the module that defines a global environment, and its name. Args: globals_dict: A dictionary that should correspond to an environment providing the values of the globals. Returns: A pair consisting of (1) module object and (2) module name (a string). Returns (None, None) if the module could not be identified. """ # The use of .items() (instead of .iteritems()) is NOT a mistake: if # a parallel thread imports a module while we iterate over # .iteritems() (not nice, but possible), we get a RuntimeError ... # Hence, we use the slightly slower but safer .items(). for name, module in sys.modules.items(): if getattr(module, '__dict__', None) is globals_dict: if name == '__main__': # Pick a more informative name for the main module. name = sys.argv[0] return (module, name) return (None, None) def _GetMainModule(): """Returns the name of the module from which execution started.""" for depth in range(1, sys.getrecursionlimit()): try: globals_of_main = sys._getframe(depth).f_globals except ValueError: return _GetModuleObjectAndName(globals_of_main)[1] raise AssertionError("No module was found") class FlagValues: """Registry of 'Flag' objects. A 'FlagValues' can then scan command line arguments, passing flag arguments through to the 'Flag' objects that it owns. It also provides easy access to the flag values. Typically only one 'FlagValues' object is needed by an application: gflags.FLAGS This class is heavily overloaded: 'Flag' objects are registered via __setitem__: FLAGS['longname'] = x # register a new flag The .value attribute of the registered 'Flag' objects can be accessed as attributes of this 'FlagValues' object, through __getattr__. Both the long and short name of the original 'Flag' objects can be used to access its value: FLAGS.longname # parsed flag value FLAGS.x # parsed flag value (short name) Command line arguments are scanned and passed to the registered 'Flag' objects through the __call__ method. Unparsed arguments, including argv[0] (e.g. the program name) are returned. argv = FLAGS(sys.argv) # scan command line arguments The original registered Flag objects can be retrieved through the use of the dictionary-like operator, __getitem__: x = FLAGS['longname'] # access the registered Flag object The str() operator of a 'FlagValues' object provides help for all of the registered 'Flag' objects. """ def __init__(self): # Since everything in this class is so heavily overloaded, the only # way of defining and using fields is to access __dict__ directly. # Dictionary: flag name (string) -> Flag object. self.__dict__['__flags'] = {} # Dictionary: module name (string) -> list of Flag objects that are defined # by that module. self.__dict__['__flags_by_module'] = {} # Dictionary: module name (string) -> list of Flag objects that are # key for that module. self.__dict__['__key_flags_by_module'] = {} # Set if we should use new style gnu_getopt rather than getopt when parsing # the args. Only possible with Python 2.3+ self.UseGnuGetOpt(False) def UseGnuGetOpt(self, use_gnu_getopt=True): self.__dict__['__use_gnu_getopt'] = use_gnu_getopt def IsGnuGetOpt(self): return self.__dict__['__use_gnu_getopt'] def FlagDict(self): return self.__dict__['__flags'] def FlagsByModuleDict(self): """Returns the dictionary of module_name -> list of defined flags. Returns: A dictionary. Its keys are module names (strings). Its values are lists of Flag objects. """ return self.__dict__['__flags_by_module'] def KeyFlagsByModuleDict(self): """Returns the dictionary of module_name -> list of key flags. Returns: A dictionary. Its keys are module names (strings). Its values are lists of Flag objects. """ return self.__dict__['__key_flags_by_module'] def _RegisterFlagByModule(self, module_name, flag): """Records the module that defines a specific flag. We keep track of which flag is defined by which module so that we can later sort the flags by module. Args: module_name: A string, the name of a Python module. flag: A Flag object, a flag that is key to the module. """ flags_by_module = self.FlagsByModuleDict() flags_by_module.setdefault(module_name, []).append(flag) def _RegisterKeyFlagForModule(self, module_name, flag): """Specifies that a flag is a key flag for a module. Args: module_name: A string, the name of a Python module. flag: A Flag object, a flag that is key to the module. """ key_flags_by_module = self.KeyFlagsByModuleDict() # The list of key flags for the module named module_name. key_flags = key_flags_by_module.setdefault(module_name, []) # Add flag, but avoid duplicates. if flag not in key_flags: key_flags.append(flag) def _GetFlagsDefinedByModule(self, module): """Returns the list of flags defined by a module. Args: module: A module object or a module name (a string). Returns: A new list of Flag objects. Caller may update this list as he wishes: none of those changes will affect the internals of this FlagValue object. """ if not isinstance(module, str): module = module.__name__ return list(self.FlagsByModuleDict().get(module, [])) def _GetKeyFlagsForModule(self, module): """Returns the list of key flags for a module. Args: module: A module object or a module name (a string) Returns: A new list of Flag objects. Caller may update this list as he wishes: none of those changes will affect the internals of this FlagValue object. """ if not isinstance(module, str): module = module.__name__ # Any flag is a key flag for the module that defined it. NOTE: # key_flags is a fresh list: we can update it without affecting the # internals of this FlagValues object. key_flags = self._GetFlagsDefinedByModule(module) # Take into account flags explicitly declared as key for a module. for flag in self.KeyFlagsByModuleDict().get(module, []): if flag not in key_flags: key_flags.append(flag) return key_flags def AppendFlagValues(self, flag_values): """Appends flags registered in another FlagValues instance. Args: flag_values: registry to copy from """ for flag_name, flag in flag_values.FlagDict().iteritems(): # Each flags with shortname appears here twice (once under its # normal name, and again with its short name). To prevent # problems (DuplicateFlagError) with double flag registration, we # perform a check to make sure that the entry we're looking at is # for its normal name. if flag_name == flag.name: self[flag_name] = flag def RemoveFlagValues(self, flag_values): """Remove flags that were previously appended from another FlagValues. Args: flag_values: registry containing flags to remove. """ for flag_name in flag_values.FlagDict(): self.__delattr__(flag_name) def __setitem__(self, name, flag): """Registers a new flag variable.""" fl = self.FlagDict() if not isinstance(flag, Flag): raise IllegalFlagValue(flag) if not isinstance(name, type("")): raise FlagsError("Flag name must be a string") if len(name) == 0: raise FlagsError("Flag name cannot be empty") # If running under pychecker, duplicate keys are likely to be # defined. Disable check for duplicate keys when pycheck'ing. if (fl.has_key(name) and not flag.allow_override and not fl[name].allow_override and not _RUNNING_PYCHECKER): raise DuplicateFlagError(name, self) short_name = flag.short_name if short_name is not None: if (fl.has_key(short_name) and not flag.allow_override and not fl[short_name].allow_override and not _RUNNING_PYCHECKER): raise DuplicateFlagError(short_name, self) fl[short_name] = flag fl[name] = flag global _exported_flags _exported_flags[name] = flag def __getitem__(self, name): """Retrieves the Flag object for the flag --name.""" return self.FlagDict()[name] def __getattr__(self, name): """Retrieves the 'value' attribute of the flag --name.""" fl = self.FlagDict() if not fl.has_key(name): raise AttributeError(name) return fl[name].value def __setattr__(self, name, value): """Sets the 'value' attribute of the flag --name.""" fl = self.FlagDict() fl[name].value = value self._AssertValidators(fl[name].validators) return value def _AssertAllValidators(self): all_validators = set() for flag in self.FlagDict().itervalues(): for validator in flag.validators: all_validators.add(validator) self._AssertValidators(all_validators) def _AssertValidators(self, validators): """Assert if all validators in the list are satisfied. Asserts validators in the order they were created. Args: validators: Iterable(gflags_validators.Validator), validators to be verified Raises: AttributeError: if validators work with a non-existing flag. IllegalFlagValue: if validation fails for at least one validator """ for validator in sorted( validators, key=lambda validator: validator.insertion_index): try: validator.Verify(self) except gflags_validators.Error, e: message = validator.PrintFlagsWithValues(self) raise IllegalFlagValue('%s: %s' % (message, str(e))) def _FlagIsRegistered(self, flag_obj): """Checks whether a Flag object is registered under some name. Note: this is non trivial: in addition to its normal name, a flag may have a short name too. In self.FlagDict(), both the normal and the short name are mapped to the same flag object. E.g., calling only "del FLAGS.short_name" is not unregistering the corresponding Flag object (it is still registered under the longer name). Args: flag_obj: A Flag object. Returns: A boolean: True iff flag_obj is registered under some name. """ flag_dict = self.FlagDict() # Check whether flag_obj is registered under its long name. name = flag_obj.name if flag_dict.get(name, None) == flag_obj: return True # Check whether flag_obj is registered under its short name. short_name = flag_obj.short_name if (short_name is not None and flag_dict.get(short_name, None) == flag_obj): return True # The flag cannot be registered under any other name, so we do not # need to do a full search through the values of self.FlagDict(). return False def __delattr__(self, flag_name): """Deletes a previously-defined flag from a flag object. This method makes sure we can delete a flag by using del flag_values_object.<flag_name> E.g., flags.DEFINE_integer('foo', 1, 'Integer flag.') del flags.FLAGS.foo Args: flag_name: A string, the name of the flag to be deleted. Raises: AttributeError: When there is no registered flag named flag_name. """ fl = self.FlagDict() if flag_name not in fl: raise AttributeError(flag_name) flag_obj = fl[flag_name] del fl[flag_name] if not self._FlagIsRegistered(flag_obj): # If the Flag object indicated by flag_name is no longer # registered (please see the docstring of _FlagIsRegistered), then # we delete the occurences of the flag object in all our internal # dictionaries. self.__RemoveFlagFromDictByModule(self.FlagsByModuleDict(), flag_obj) self.__RemoveFlagFromDictByModule(self.KeyFlagsByModuleDict(), flag_obj) def __RemoveFlagFromDictByModule(self, flags_by_module_dict, flag_obj): """Removes a flag object from a module -> list of flags dictionary. Args: flags_by_module_dict: A dictionary that maps module names to lists of flags. flag_obj: A flag object. """ for unused_module, flags_in_module in flags_by_module_dict.iteritems(): # while (as opposed to if) takes care of multiple occurences of a # flag in the list for the same module. while flag_obj in flags_in_module: flags_in_module.remove(flag_obj) def SetDefault(self, name, value): """Changes the default value of the named flag object.""" fl = self.FlagDict() if not fl.has_key(name): raise AttributeError(name) fl[name].SetDefault(value) self._AssertValidators(fl[name].validators) def __contains__(self, name): """Returns True if name is a value (flag) in the dict.""" return name in self.FlagDict() has_key = __contains__ # a synonym for __contains__() def __iter__(self): return self.FlagDict().iterkeys() def __call__(self, argv): """Parses flags from argv; stores parsed flags into this FlagValues object. All unparsed arguments are returned. Flags are parsed using the GNU Program Argument Syntax Conventions, using getopt: http://www.gnu.org/software/libc/manual/html_mono/libc.html#Getopt Args: argv: argument list. Can be of any type that may be converted to a list. Returns: The list of arguments not parsed as options, including argv[0] Raises: FlagsError: on any parsing error """ # Support any sequence type that can be converted to a list argv = list(argv) shortopts = "" longopts = [] fl = self.FlagDict() # This pre parses the argv list for --flagfile=<> options. argv = argv[:1] + self.ReadFlagsFromFiles(argv[1:], force_gnu=False) # Correct the argv to support the google style of passing boolean # parameters. Boolean parameters may be passed by using --mybool, # --nomybool, --mybool=(true|false|1|0). getopt does not support # having options that may or may not have a parameter. We replace # instances of the short form --mybool and --nomybool with their # full forms: --mybool=(true|false). original_argv = list(argv) # list() makes a copy shortest_matches = None for name, flag in fl.items(): if not flag.boolean: continue if shortest_matches is None: # Determine the smallest allowable prefix for all flag names shortest_matches = self.ShortestUniquePrefixes(fl) no_name = 'no' + name prefix = shortest_matches[name] no_prefix = shortest_matches[no_name] # Replace all occurences of this boolean with extended forms for arg_idx in range(1, len(argv)): arg = argv[arg_idx] if arg.find('=') >= 0: continue if arg.startswith('--'+prefix) and ('--'+name).startswith(arg): argv[arg_idx] = ('--%s=true' % name) elif arg.startswith('--'+no_prefix) and ('--'+no_name).startswith(arg): argv[arg_idx] = ('--%s=false' % name) # Loop over all of the flags, building up the lists of short options # and long options that will be passed to getopt. Short options are # specified as a string of letters, each letter followed by a colon # if it takes an argument. Long options are stored in an array of # strings. Each string ends with an '=' if it takes an argument. for name, flag in fl.items(): longopts.append(name + "=") if len(name) == 1: # one-letter option: allow short flag type also shortopts += name if not flag.boolean: shortopts += ":" longopts.append('undefok=') undefok_flags = [] # In case --undefok is specified, loop to pick up unrecognized # options one by one. unrecognized_opts = [] args = argv[1:] while True: try: if self.__dict__['__use_gnu_getopt']: optlist, unparsed_args = getopt.gnu_getopt(args, shortopts, longopts) else: optlist, unparsed_args = getopt.getopt(args, shortopts, longopts) break except getopt.GetoptError, e: if not e.opt or e.opt in fl: # Not an unrecognized option, reraise the exception as a FlagsError raise FlagsError(e) # Remove offender from args and try again for arg_index in range(len(args)): if ((args[arg_index] == '--' + e.opt) or (args[arg_index] == '-' + e.opt) or (args[arg_index].startswith('--' + e.opt + '='))): unrecognized_opts.append((e.opt, args[arg_index])) args = args[0:arg_index] + args[arg_index+1:] break else: # We should have found the option, so we don't expect to get # here. We could assert, but raising the original exception # might work better. raise FlagsError(e) for name, arg in optlist: if name == '--undefok': flag_names = arg.split(',') undefok_flags.extend(flag_names) # For boolean flags, if --undefok=boolflag is specified, then we should # also accept --noboolflag, in addition to --boolflag. # Since we don't know the type of the undefok'd flag, this will affect # non-boolean flags as well. # NOTE: You shouldn't use --undefok=noboolflag, because then we will # accept --nonoboolflag here. We are choosing not to do the conversion # from noboolflag -> boolflag because of the ambiguity that flag names # can start with 'no'. undefok_flags.extend('no' + name for name in flag_names) continue if name.startswith('--'): # long option name = name[2:] short_option = 0 else: # short option name = name[1:] short_option = 1 if fl.has_key(name): flag = fl[name] if flag.boolean and short_option: arg = 1 flag.Parse(arg) # If there were unrecognized options, raise an exception unless # the options were named via --undefok. for opt, value in unrecognized_opts: if opt not in undefok_flags: raise UnrecognizedFlagError(opt, value) if unparsed_args: if self.__dict__['__use_gnu_getopt']: # if using gnu_getopt just return the program name + remainder of argv. ret_val = argv[:1] + unparsed_args else: # unparsed_args becomes the first non-flag detected by getopt to # the end of argv. Because argv may have been modified above, # return original_argv for this region. ret_val = argv[:1] + original_argv[-len(unparsed_args):] else: ret_val = argv[:1] self._AssertAllValidators() return ret_val def Reset(self): """Resets the values to the point before FLAGS(argv) was called.""" for f in self.FlagDict().values(): f.Unparse() def RegisteredFlags(self): """Returns: a list of the names and short names of all registered flags.""" return self.FlagDict().keys() def FlagValuesDict(self): """Returns: a dictionary that maps flag names to flag values.""" flag_values = {} for flag_name in self.RegisteredFlags(): flag = self.FlagDict()[flag_name] flag_values[flag_name] = flag.value return flag_values def __str__(self): """Generates a help string for all known flags.""" return self.GetHelp() def GetHelp(self, prefix=''): """Generates a help string for all known flags.""" helplist = [] flags_by_module = self.FlagsByModuleDict() if flags_by_module: modules = flags_by_module.keys() modules.sort() # Print the help for the main module first, if possible. main_module = _GetMainModule() if main_module in modules: modules.remove(main_module) modules = [main_module] + modules for module in modules: self.__RenderOurModuleFlags(module, helplist) self.__RenderModuleFlags('gflags', _SPECIAL_FLAGS.FlagDict().values(), helplist) else: # Just print one long list of flags. self.__RenderFlagList( self.FlagDict().values() + _SPECIAL_FLAGS.FlagDict().values(), helplist, prefix) return '\n'.join(helplist) def __RenderModuleFlags(self, module, flags, output_lines, prefix=""): """Generates a help string for a given module.""" if not isinstance(module, str): module = module.__name__ output_lines.append('\n%s%s:' % (prefix, module)) self.__RenderFlagList(flags, output_lines, prefix + " ") def __RenderOurModuleFlags(self, module, output_lines, prefix=""): """Generates a help string for a given module.""" flags = self._GetFlagsDefinedByModule(module) if flags: self.__RenderModuleFlags(module, flags, output_lines, prefix) def __RenderOurModuleKeyFlags(self, module, output_lines, prefix=""): """Generates a help string for the key flags of a given module. Args: module: A module object or a module name (a string). output_lines: A list of strings. The generated help message lines will be appended to this list. prefix: A string that is prepended to each generated help line. """ key_flags = self._GetKeyFlagsForModule(module) if key_flags: self.__RenderModuleFlags(module, key_flags, output_lines, prefix) def ModuleHelp(self, module): """Describe the key flags of a module. Args: module: A module object or a module name (a string). Returns: string describing the key flags of a module. """ helplist = [] self.__RenderOurModuleKeyFlags(module, helplist) return '\n'.join(helplist) def MainModuleHelp(self): """Describe the key flags of the main module. Returns: string describing the key flags of a module. """ return self.ModuleHelp(_GetMainModule()) def __RenderFlagList(self, flaglist, output_lines, prefix=" "): fl = self.FlagDict() special_fl = _SPECIAL_FLAGS.FlagDict() flaglist = [(flag.name, flag) for flag in flaglist] flaglist.sort() flagset = {} for (name, flag) in flaglist: # It's possible this flag got deleted or overridden since being # registered in the per-module flaglist. Check now against the # canonical source of current flag information, the FlagDict. if fl.get(name, None) != flag and special_fl.get(name, None) != flag: # a different flag is using this name now continue # only print help once if flagset.has_key(flag): continue flagset[flag] = 1 flaghelp = "" if flag.short_name: flaghelp += "-%s," % flag.short_name if flag.boolean: flaghelp += "--[no]%s" % flag.name + ":" else: flaghelp += "--%s" % flag.name + ":" flaghelp += " " if flag.help: flaghelp += flag.help flaghelp = TextWrap(flaghelp, indent=prefix+" ", firstline_indent=prefix) if flag.default_as_str: flaghelp += "\n" flaghelp += TextWrap("(default: %s)" % flag.default_as_str, indent=prefix+" ") if flag.parser.syntactic_help: flaghelp += "\n" flaghelp += TextWrap("(%s)" % flag.parser.syntactic_help, indent=prefix+" ") output_lines.append(flaghelp) def get(self, name, default): """Returns the value of a flag (if not None) or a default value. Args: name: A string, the name of a flag. default: Default value to use if the flag value is None. """ value = self.__getattr__(name) if value is not None: # Can't do if not value, b/c value might be '0' or "" return value else: return default def ShortestUniquePrefixes(self, fl): """Returns: dictionary; maps flag names to their shortest unique prefix.""" # Sort the list of flag names sorted_flags = [] for name, flag in fl.items(): sorted_flags.append(name) if flag.boolean: sorted_flags.append('no%s' % name) sorted_flags.sort() # For each name in the sorted list, determine the shortest unique # prefix by comparing itself to the next name and to the previous # name (the latter check uses cached info from the previous loop). shortest_matches = {} prev_idx = 0 for flag_idx in range(len(sorted_flags)): curr = sorted_flags[flag_idx] if flag_idx == (len(sorted_flags) - 1): next = None else: next = sorted_flags[flag_idx+1] next_len = len(next) for curr_idx in range(len(curr)): if (next is None or curr_idx >= next_len or curr[curr_idx] != next[curr_idx]): # curr longer than next or no more chars in common shortest_matches[curr] = curr[:max(prev_idx, curr_idx) + 1] prev_idx = curr_idx break else: # curr shorter than (or equal to) next shortest_matches[curr] = curr prev_idx = curr_idx + 1 # next will need at least one more char return shortest_matches def __IsFlagFileDirective(self, flag_string): """Checks whether flag_string contain a --flagfile=<foo> directive.""" if isinstance(flag_string, type("")): if flag_string.startswith('--flagfile='): return 1 elif flag_string == '--flagfile': return 1 elif flag_string.startswith('-flagfile='): return 1 elif flag_string == '-flagfile': return 1 else: return 0 return 0 def ExtractFilename(self, flagfile_str): """Returns filename from a flagfile_str of form -[-]flagfile=filename. The cases of --flagfile foo and -flagfile foo shouldn't be hitting this function, as they are dealt with in the level above this function. """ if flagfile_str.startswith('--flagfile='): return os.path.expanduser((flagfile_str[(len('--flagfile=')):]).strip()) elif flagfile_str.startswith('-flagfile='): return os.path.expanduser((flagfile_str[(len('-flagfile=')):]).strip()) else: raise FlagsError('Hit illegal --flagfile type: %s' % flagfile_str) def __GetFlagFileLines(self, filename, parsed_file_list): """Returns the useful (!=comments, etc) lines from a file with flags. Args: filename: A string, the name of the flag file. parsed_file_list: A list of the names of the files we have already read. MUTATED BY THIS FUNCTION. Returns: List of strings. See the note below. NOTE(springer): This function checks for a nested --flagfile=<foo> tag and handles the lower file recursively. It returns a list of all the lines that _could_ contain command flags. This is EVERYTHING except whitespace lines and comments (lines starting with '#' or '//'). """ line_list = [] # All line from flagfile. flag_line_list = [] # Subset of lines w/o comments, blanks, flagfile= tags. try: file_obj = open(filename, 'r') except IOError, e_msg: print e_msg print 'ERROR:: Unable to open flagfile: %s' % (filename) return flag_line_list line_list = file_obj.readlines() file_obj.close() parsed_file_list.append(filename) # This is where we check each line in the file we just read. for line in line_list: if line.isspace(): pass # Checks for comment (a line that starts with '#'). elif line.startswith('#') or line.startswith('//'): pass # Checks for a nested "--flagfile=<bar>" flag in the current file. # If we find one, recursively parse down into that file. elif self.__IsFlagFileDirective(line): sub_filename = self.ExtractFilename(line) # We do a little safety check for reparsing a file we've already done. if not sub_filename in parsed_file_list: included_flags = self.__GetFlagFileLines(sub_filename, parsed_file_list) flag_line_list.extend(included_flags) else: # Case of hitting a circularly included file. print >>sys.stderr, ('Warning: Hit circular flagfile dependency: %s' % sub_filename) else: # Any line that's not a comment or a nested flagfile should get # copied into 2nd position. This leaves earlier arguements # further back in the list, thus giving them higher priority. flag_line_list.append(line.strip()) return flag_line_list def ReadFlagsFromFiles(self, argv, force_gnu=True): """Processes command line args, but also allow args to be read from file. Args: argv: A list of strings, usually sys.argv[1:], which may contain one or more flagfile directives of the form --flagfile="./filename". Note that the name of the program (sys.argv[0]) should be omitted. force_gnu: If False, --flagfile parsing obeys normal flag semantics. If True, --flagfile parsing instead follows gnu_getopt semantics. *** WARNING *** force_gnu=False may become the future default! Returns: A new list which has the original list combined with what we read from any flagfile(s). References: Global gflags.FLAG class instance. This function should be called before the normal FLAGS(argv) call. This function scans the input list for a flag that looks like: --flagfile=<somefile>. Then it opens <somefile>, reads all valid key and value pairs and inserts them into the input list between the first item of the list and any subsequent items in the list. Note that your application's flags are still defined the usual way using gflags DEFINE_flag() type functions. Notes (assuming we're getting a commandline of some sort as our input): --> Flags from the command line argv _should_ always take precedence! --> A further "--flagfile=<otherfile.cfg>" CAN be nested in a flagfile. It will be processed after the parent flag file is done. --> For duplicate flags, first one we hit should "win". --> In a flagfile, a line beginning with # or // is a comment. --> Entirely blank lines _should_ be ignored. """ parsed_file_list = [] rest_of_args = argv new_argv = [] while rest_of_args: current_arg = rest_of_args[0] rest_of_args = rest_of_args[1:] if self.__IsFlagFileDirective(current_arg): # This handles the case of -(-)flagfile foo. In this case the # next arg really is part of this one. if current_arg == '--flagfile' or current_arg == '-flagfile': if not rest_of_args: raise IllegalFlagValue('--flagfile with no argument') flag_filename = os.path.expanduser(rest_of_args[0]) rest_of_args = rest_of_args[1:] else: # This handles the case of (-)-flagfile=foo. flag_filename = self.ExtractFilename(current_arg) new_argv[0:0] = self.__GetFlagFileLines(flag_filename, parsed_file_list) else: new_argv.append(current_arg) # Stop parsing after '--', like getopt and gnu_getopt. if current_arg == '--': break # Stop parsing after a non-flag, like getopt. if not current_arg.startswith('-'): if not force_gnu and not self.__dict__['__use_gnu_getopt']: break if rest_of_args: new_argv.extend(rest_of_args) return new_argv def FlagsIntoString(self): """Returns a string with the flags assignments from this FlagValues object. This function ignores flags whose value is None. Each flag assignment is separated by a newline. NOTE: MUST mirror the behavior of the C++ function CommandlineFlagsIntoString from google3/base/commandlineflags.cc. """ s = '' for flag in self.FlagDict().values(): if flag.value is not None: s += flag.Serialize() + '\n' return s def AppendFlagsIntoFile(self, filename): """Appends all flags assignments from this FlagInfo object to a file. Output will be in the format of a flagfile. NOTE: MUST mirror the behavior of the C++ version of AppendFlagsIntoFile from google3/base/commandlineflags.cc. """ out_file = open(filename, 'a') out_file.write(self.FlagsIntoString()) out_file.close() def WriteHelpInXMLFormat(self, outfile=None): """Outputs flag documentation in XML format. NOTE: We use element names that are consistent with those used by the C++ command-line flag library, from google3/base/commandlineflags_reporting.cc. We also use a few new elements (e.g., <key>), but we do not interfere / overlap with existing XML elements used by the C++ library. Please maintain this consistency. Args: outfile: File object we write to. Default None means sys.stdout. """ outfile = outfile or sys.stdout outfile.write('<?xml version=\"1.0\"?>\n') outfile.write('<AllFlags>\n') indent = ' ' _WriteSimpleXMLElement(outfile, 'program', os.path.basename(sys.argv[0]), indent) usage_doc = sys.modules['__main__'].__doc__ if not usage_doc: usage_doc = '\nUSAGE: %s [flags]\n' % sys.argv[0] else: usage_doc = usage_doc.replace('%s', sys.argv[0]) _WriteSimpleXMLElement(outfile, 'usage', usage_doc, indent) # Get list of key flags for the main module. key_flags = self._GetKeyFlagsForModule(_GetMainModule()) # Sort flags by declaring module name and next by flag name. flags_by_module = self.FlagsByModuleDict() all_module_names = list(flags_by_module.keys()) all_module_names.sort() for module_name in all_module_names: flag_list = [(f.name, f) for f in flags_by_module[module_name]] flag_list.sort() for unused_flag_name, flag in flag_list: is_key = flag in key_flags flag.WriteInfoInXMLFormat(outfile, module_name, is_key=is_key, indent=indent) outfile.write('</AllFlags>\n') outfile.flush() def AddValidator(self, validator): """Register new flags validator to be checked. Args: validator: gflags_validators.Validator Raises: AttributeError: if validators work with a non-existing flag. """ for flag_name in validator.GetFlagsNames(): flag = self.FlagDict()[flag_name] flag.validators.append(validator) # end of FlagValues definition # The global FlagValues instance FLAGS = FlagValues() def _MakeXMLSafe(s): """Escapes <, >, and & from s, and removes XML 1.0-illegal chars.""" s = cgi.escape(s) # Escape <, >, and & # Remove characters that cannot appear in an XML 1.0 document # (http://www.w3.org/TR/REC-xml/#charsets). # # NOTE: if there are problems with current solution, one may move to # XML 1.1, which allows such chars, if they're entity-escaped (&#xHH;). s = re.sub(r'[\x00-\x08\x0b\x0c\x0e-\x1f]', '', s) return s def _WriteSimpleXMLElement(outfile, name, value, indent): """Writes a simple XML element. Args: outfile: File object we write the XML element to. name: A string, the name of XML element. value: A Python object, whose string representation will be used as the value of the XML element. indent: A string, prepended to each line of generated output. """ value_str = str(value) if isinstance(value, bool): # Display boolean values as the C++ flag library does: no caps. value_str = value_str.lower() outfile.write('%s<%s>%s</%s>\n' % (indent, name, _MakeXMLSafe(value_str), name)) class Flag: """Information about a command-line flag. 'Flag' objects define the following fields: .name - the name for this flag .default - the default value for this flag .default_as_str - default value as repr'd string, e.g., "'true'" (or None) .value - the most recent parsed value of this flag; set by Parse() .help - a help string or None if no help is available .short_name - the single letter alias for this flag (or None) .boolean - if 'true', this flag does not accept arguments .present - true if this flag was parsed from command line flags. .parser - an ArgumentParser object .serializer - an ArgumentSerializer object .allow_override - the flag may be redefined without raising an error The only public method of a 'Flag' object is Parse(), but it is typically only called by a 'FlagValues' object. The Parse() method is a thin wrapper around the 'ArgumentParser' Parse() method. The parsed value is saved in .value, and the .present attribute is updated. If this flag was already present, a FlagsError is raised. Parse() is also called during __init__ to parse the default value and initialize the .value attribute. This enables other python modules to safely use flags even if the __main__ module neglects to parse the command line arguments. The .present attribute is cleared after __init__ parsing. If the default value is set to None, then the __init__ parsing step is skipped and the .value attribute is initialized to None. Note: The default value is also presented to the user in the help string, so it is important that it be a legal value for this flag. """ def __init__(self, parser, serializer, name, default, help_string, short_name=None, boolean=0, allow_override=0): self.name = name if not help_string: help_string = '(no help available)' self.help = help_string self.short_name = short_name self.boolean = boolean self.present = 0 self.parser = parser self.serializer = serializer self.allow_override = allow_override self.value = None self.validators = [] self.SetDefault(default) def __GetParsedValueAsString(self, value): if value is None: return None if self.serializer: return repr(self.serializer.Serialize(value)) if self.boolean: if value: return repr('true') else: return repr('false') return repr(str(value)) def Parse(self, argument): try: self.value = self.parser.Parse(argument) except ValueError, e: # recast ValueError as IllegalFlagValue raise IllegalFlagValue("flag --%s=%s: %s" % (self.name, argument, e)) self.present += 1 def Unparse(self): if self.default is None: self.value = None else: self.Parse(self.default) self.present = 0 def Serialize(self): if self.value is None: return '' if self.boolean: if self.value: return "--%s" % self.name else: return "--no%s" % self.name else: if not self.serializer: raise FlagsError("Serializer not present for flag %s" % self.name) return "--%s=%s" % (self.name, self.serializer.Serialize(self.value)) def SetDefault(self, value): """Changes the default value (and current value too) for this Flag.""" # We can't allow a None override because it may end up not being # passed to C++ code when we're overriding C++ flags. So we # cowardly bail out until someone fixes the semantics of trying to # pass None to a C++ flag. See swig_flags.Init() for details on # this behavior. # TODO(olexiy): Users can directly call this method, bypassing all flags # validators (we don't have FlagValues here, so we can not check # validators). # The simplest solution I see is to make this method private. # Another approach would be to store reference to the corresponding # FlagValues with each flag, but this seems to be an overkill. if value is None and self.allow_override: raise DuplicateFlagCannotPropagateNoneToSwig(self.name) self.default = value self.Unparse() self.default_as_str = self.__GetParsedValueAsString(self.value) def Type(self): """Returns: a string that describes the type of this Flag.""" # NOTE: we use strings, and not the types.*Type constants because # our flags can have more exotic types, e.g., 'comma separated list # of strings', 'whitespace separated list of strings', etc. return self.parser.Type() def WriteInfoInXMLFormat(self, outfile, module_name, is_key=False, indent=''): """Writes common info about this flag, in XML format. This is information that is relevant to all flags (e.g., name, meaning, etc.). If you defined a flag that has some other pieces of info, then please override _WriteCustomInfoInXMLFormat. Please do NOT override this method. Args: outfile: File object we write to. module_name: A string, the name of the module that defines this flag. is_key: A boolean, True iff this flag is key for main module. indent: A string that is prepended to each generated line. """ outfile.write(indent + '<flag>\n') inner_indent = indent + ' ' if is_key: _WriteSimpleXMLElement(outfile, 'key', 'yes', inner_indent) _WriteSimpleXMLElement(outfile, 'file', module_name, inner_indent) # Print flag features that are relevant for all flags. _WriteSimpleXMLElement(outfile, 'name', self.name, inner_indent) if self.short_name: _WriteSimpleXMLElement(outfile, 'short_name', self.short_name, inner_indent) if self.help: _WriteSimpleXMLElement(outfile, 'meaning', self.help, inner_indent) # The default flag value can either be represented as a string like on the # command line, or as a Python object. We serialize this value in the # latter case in order to remain consistent. if self.serializer and not isinstance(self.default, str): default_serialized = self.serializer.Serialize(self.default) else: default_serialized = self.default _WriteSimpleXMLElement(outfile, 'default', default_serialized, inner_indent) _WriteSimpleXMLElement(outfile, 'current', self.value, inner_indent) _WriteSimpleXMLElement(outfile, 'type', self.Type(), inner_indent) # Print extra flag features this flag may have. self._WriteCustomInfoInXMLFormat(outfile, inner_indent) outfile.write(indent + '</flag>\n') def _WriteCustomInfoInXMLFormat(self, outfile, indent): """Writes extra info about this flag, in XML format. "Extra" means "not already printed by WriteInfoInXMLFormat above." Args: outfile: File object we write to. indent: A string that is prepended to each generated line. """ # Usually, the parser knows the extra details about the flag, so # we just forward the call to it. self.parser.WriteCustomInfoInXMLFormat(outfile, indent) # End of Flag definition class _ArgumentParserCache(type): """Metaclass used to cache and share argument parsers among flags.""" _instances = {} def __call__(mcs, *args, **kwargs): """Returns an instance of the argument parser cls. This method overrides behavior of the __new__ methods in all subclasses of ArgumentParser (inclusive). If an instance for mcs with the same set of arguments exists, this instance is returned, otherwise a new instance is created. If any keyword arguments are defined, or the values in args are not hashable, this method always returns a new instance of cls. Args: args: Positional initializer arguments. kwargs: Initializer keyword arguments. Returns: An instance of cls, shared or new. """ if kwargs: return type.__call__(mcs, *args, **kwargs) else: instances = mcs._instances key = (mcs,) + tuple(args) try: return instances[key] except KeyError: # No cache entry for key exists, create a new one. return instances.setdefault(key, type.__call__(mcs, *args)) except TypeError: # An object in args cannot be hashed, always return # a new instance. return type.__call__(mcs, *args) class ArgumentParser(object): """Base class used to parse and convert arguments. The Parse() method checks to make sure that the string argument is a legal value and convert it to a native type. If the value cannot be converted, it should throw a 'ValueError' exception with a human readable explanation of why the value is illegal. Subclasses should also define a syntactic_help string which may be presented to the user to describe the form of the legal values. Argument parser classes must be stateless, since instances are cached and shared between flags. Initializer arguments are allowed, but all member variables must be derived from initializer arguments only. """ __metaclass__ = _ArgumentParserCache syntactic_help = "" def Parse(self, argument): """Default implementation: always returns its argument unmodified.""" return argument def Type(self): return 'string' def WriteCustomInfoInXMLFormat(self, outfile, indent): pass class ArgumentSerializer: """Base class for generating string representations of a flag value.""" def Serialize(self, value): return str(value) class ListSerializer(ArgumentSerializer): def __init__(self, list_sep): self.list_sep = list_sep def Serialize(self, value): return self.list_sep.join([str(x) for x in value]) # Flags validators def RegisterValidator(flag_name, checker, message='Flag validation failed', flag_values=FLAGS): """Adds a constraint, which will be enforced during program execution. The constraint is validated when flags are initially parsed, and after each change of the corresponding flag's value. Args: flag_name: string, name of the flag to be checked. checker: method to validate the flag. input - value of the corresponding flag (string, boolean, etc. This value will be passed to checker by the library). See file's docstring for examples. output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise gflags_validators.Error(desired_error_message). message: error text to be shown to the user if checker returns False. If checker raises gflags_validators.Error, message from the raised Error will be shown. flag_values: FlagValues Raises: AttributeError: if flag_name is not registered as a valid flag name. """ flag_values.AddValidator(gflags_validators.SimpleValidator(flag_name, checker, message)) def MarkFlagAsRequired(flag_name, flag_values=FLAGS): """Ensure that flag is not None during program execution. Registers a flag validator, which will follow usual validator rules. Args: flag_name: string, name of the flag flag_values: FlagValues Raises: AttributeError: if flag_name is not registered as a valid flag name. """ RegisterValidator(flag_name, lambda value: value is not None, message='Flag --%s must be specified.' % flag_name, flag_values=flag_values) def _RegisterBoundsValidatorIfNeeded(parser, name, flag_values): """Enforce lower and upper bounds for numeric flags. Args: parser: NumericParser (either FloatParser or IntegerParser). Provides lower and upper bounds, and help text to display. name: string, name of the flag flag_values: FlagValues """ if parser.lower_bound is not None or parser.upper_bound is not None: def Checker(value): if value is not None and parser.IsOutsideBounds(value): message = '%s is not %s' % (value, parser.syntactic_help) raise gflags_validators.Error(message) return True RegisterValidator(name, Checker, flag_values=flag_values) # The DEFINE functions are explained in mode details in the module doc string. def DEFINE(parser, name, default, help, flag_values=FLAGS, serializer=None, **args): """Registers a generic Flag object. NOTE: in the docstrings of all DEFINE* functions, "registers" is short for "creates a new flag and registers it". Auxiliary function: clients should use the specialized DEFINE_<type> function instead. Args: parser: ArgumentParser that is used to parse the flag arguments. name: A string, the flag name. default: The default value of the flag. help: A help string. flag_values: FlagValues object the flag will be registered with. serializer: ArgumentSerializer that serializes the flag value. args: Dictionary with extra keyword args that are passes to the Flag __init__. """ DEFINE_flag(Flag(parser, serializer, name, default, help, **args), flag_values) def DEFINE_flag(flag, flag_values=FLAGS): """Registers a 'Flag' object with a 'FlagValues' object. By default, the global FLAGS 'FlagValue' object is used. Typical users will use one of the more specialized DEFINE_xxx functions, such as DEFINE_string or DEFINE_integer. But developers who need to create Flag objects themselves should use this function to register their flags. """ # copying the reference to flag_values prevents pychecker warnings fv = flag_values fv[flag.name] = flag # Tell flag_values who's defining the flag. if isinstance(flag_values, FlagValues): # Regarding the above isinstance test: some users pass funny # values of flag_values (e.g., {}) in order to avoid the flag # registration (in the past, there used to be a flag_values == # FLAGS test here) and redefine flags with the same name (e.g., # debug). To avoid breaking their code, we perform the # registration only if flag_values is a real FlagValues object. flag_values._RegisterFlagByModule(_GetCallingModule(), flag) def _InternalDeclareKeyFlags(flag_names, flag_values=FLAGS, key_flag_values=None): """Declares a flag as key for the calling module. Internal function. User code should call DECLARE_key_flag or ADOPT_module_key_flags instead. Args: flag_names: A list of strings that are names of already-registered Flag objects. flag_values: A FlagValues object that the flags listed in flag_names have registered with (the value of the flag_values argument from the DEFINE_* calls that defined those flags). This should almost never need to be overridden. key_flag_values: A FlagValues object that (among possibly many other things) keeps track of the key flags for each module. Default None means "same as flag_values". This should almost never need to be overridden. Raises: UnrecognizedFlagError: when we refer to a flag that was not defined yet. """ key_flag_values = key_flag_values or flag_values module = _GetCallingModule() for flag_name in flag_names: if flag_name not in flag_values: raise UnrecognizedFlagError(flag_name) flag = flag_values.FlagDict()[flag_name] key_flag_values._RegisterKeyFlagForModule(module, flag) def DECLARE_key_flag(flag_name, flag_values=FLAGS): """Declares one flag as key to the current module. Key flags are flags that are deemed really important for a module. They are important when listing help messages; e.g., if the --helpshort command-line flag is used, then only the key flags of the main module are listed (instead of all flags, as in the case of --help). Sample usage: flags.DECLARED_key_flag('flag_1') Args: flag_name: A string, the name of an already declared flag. (Redeclaring flags as key, including flags implicitly key because they were declared in this module, is a no-op.) flag_values: A FlagValues object. This should almost never need to be overridden. """ if flag_name in _SPECIAL_FLAGS: # Take care of the special flags, e.g., --flagfile, --undefok. # These flags are defined in _SPECIAL_FLAGS, and are treated # specially during flag parsing, taking precedence over the # user-defined flags. _InternalDeclareKeyFlags([flag_name], flag_values=_SPECIAL_FLAGS, key_flag_values=flag_values) return _InternalDeclareKeyFlags([flag_name], flag_values=flag_values) def ADOPT_module_key_flags(module, flag_values=FLAGS): """Declares that all flags key to a module are key to the current module. Args: module: A module object. flag_values: A FlagValues object. This should almost never need to be overridden. Raises: FlagsError: When given an argument that is a module name (a string), instead of a module object. """ # NOTE(salcianu): an even better test would be if not # isinstance(module, types.ModuleType) but I didn't want to import # types for such a tiny use. if isinstance(module, str): raise FlagsError('Received module name %s; expected a module object.' % module) _InternalDeclareKeyFlags( [f.name for f in flag_values._GetKeyFlagsForModule(module.__name__)], flag_values=flag_values) # If module is this flag module, take _SPECIAL_FLAGS into account. if module == _GetThisModuleObjectAndName()[0]: _InternalDeclareKeyFlags( # As we associate flags with _GetCallingModule(), the special # flags defined in this module are incorrectly registered with # a different module. So, we can't use _GetKeyFlagsForModule. # Instead, we take all flags from _SPECIAL_FLAGS (a private # FlagValues, where no other module should register flags). [f.name for f in _SPECIAL_FLAGS.FlagDict().values()], flag_values=_SPECIAL_FLAGS, key_flag_values=flag_values) # # STRING FLAGS # def DEFINE_string(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value can be any string.""" parser = ArgumentParser() serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) # # BOOLEAN FLAGS # # and the special HELP flags. class BooleanParser(ArgumentParser): """Parser of boolean values.""" def Convert(self, argument): """Converts the argument to a boolean; raise ValueError on errors.""" if type(argument) == str: if argument.lower() in ['true', 't', '1']: return True elif argument.lower() in ['false', 'f', '0']: return False bool_argument = bool(argument) if argument == bool_argument: # The argument is a valid boolean (True, False, 0, or 1), and not just # something that always converts to bool (list, string, int, etc.). return bool_argument raise ValueError('Non-boolean argument to boolean flag', argument) def Parse(self, argument): val = self.Convert(argument) return val def Type(self): return 'bool' class BooleanFlag(Flag): """Basic boolean flag. Boolean flags do not take any arguments, and their value is either True (1) or False (0). The false value is specified on the command line by prepending the word 'no' to either the long or the short flag name. For example, if a Boolean flag was created whose long name was 'update' and whose short name was 'x', then this flag could be explicitly unset through either --noupdate or --nox. """ def __init__(self, name, default, help, short_name=None, **args): p = BooleanParser() Flag.__init__(self, p, None, name, default, help, short_name, 1, **args) if not self.help: self.help = "a boolean value" def DEFINE_boolean(name, default, help, flag_values=FLAGS, **args): """Registers a boolean flag. Such a boolean flag does not take an argument. If a user wants to specify a false value explicitly, the long option beginning with 'no' must be used: i.e. --noflag This flag will have a value of None, True or False. None is possible if default=None and the user does not specify the flag on the command line. """ DEFINE_flag(BooleanFlag(name, default, help, **args), flag_values) # Match C++ API to unconfuse C++ people. DEFINE_bool = DEFINE_boolean class HelpFlag(BooleanFlag): """ HelpFlag is a special boolean flag that prints usage information and raises a SystemExit exception if it is ever found in the command line arguments. Note this is called with allow_override=1, so other apps can define their own --help flag, replacing this one, if they want. """ def __init__(self): BooleanFlag.__init__(self, "help", 0, "show this help", short_name="?", allow_override=1) def Parse(self, arg): if arg: doc = sys.modules["__main__"].__doc__ flags = str(FLAGS) print doc or ("\nUSAGE: %s [flags]\n" % sys.argv[0]) if flags: print "flags:" print flags sys.exit(1) class HelpXMLFlag(BooleanFlag): """Similar to HelpFlag, but generates output in XML format.""" def __init__(self): BooleanFlag.__init__(self, 'helpxml', False, 'like --help, but generates XML output', allow_override=1) def Parse(self, arg): if arg: FLAGS.WriteHelpInXMLFormat(sys.stdout) sys.exit(1) class HelpshortFlag(BooleanFlag): """ HelpshortFlag is a special boolean flag that prints usage information for the "main" module, and rasies a SystemExit exception if it is ever found in the command line arguments. Note this is called with allow_override=1, so other apps can define their own --helpshort flag, replacing this one, if they want. """ def __init__(self): BooleanFlag.__init__(self, "helpshort", 0, "show usage only for this module", allow_override=1) def Parse(self, arg): if arg: doc = sys.modules["__main__"].__doc__ flags = FLAGS.MainModuleHelp() print doc or ("\nUSAGE: %s [flags]\n" % sys.argv[0]) if flags: print "flags:" print flags sys.exit(1) # # Numeric parser - base class for Integer and Float parsers # class NumericParser(ArgumentParser): """Parser of numeric values. Parsed value may be bounded to a given upper and lower bound. """ def IsOutsideBounds(self, val): return ((self.lower_bound is not None and val < self.lower_bound) or (self.upper_bound is not None and val > self.upper_bound)) def Parse(self, argument): val = self.Convert(argument) if self.IsOutsideBounds(val): raise ValueError("%s is not %s" % (val, self.syntactic_help)) return val def WriteCustomInfoInXMLFormat(self, outfile, indent): if self.lower_bound is not None: _WriteSimpleXMLElement(outfile, 'lower_bound', self.lower_bound, indent) if self.upper_bound is not None: _WriteSimpleXMLElement(outfile, 'upper_bound', self.upper_bound, indent) def Convert(self, argument): """Default implementation: always returns its argument unmodified.""" return argument # End of Numeric Parser # # FLOAT FLAGS # class FloatParser(NumericParser): """Parser of floating point values. Parsed value may be bounded to a given upper and lower bound. """ number_article = "a" number_name = "number" syntactic_help = " ".join((number_article, number_name)) def __init__(self, lower_bound=None, upper_bound=None): super(FloatParser, self).__init__() self.lower_bound = lower_bound self.upper_bound = upper_bound sh = self.syntactic_help if lower_bound is not None and upper_bound is not None: sh = ("%s in the range [%s, %s]" % (sh, lower_bound, upper_bound)) elif lower_bound == 0: sh = "a non-negative %s" % self.number_name elif upper_bound == 0: sh = "a non-positive %s" % self.number_name elif upper_bound is not None: sh = "%s <= %s" % (self.number_name, upper_bound) elif lower_bound is not None: sh = "%s >= %s" % (self.number_name, lower_bound) self.syntactic_help = sh def Convert(self, argument): """Converts argument to a float; raises ValueError on errors.""" return float(argument) def Type(self): return 'float' # End of FloatParser def DEFINE_float(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value must be a float. If lower_bound or upper_bound are set, then this flag must be within the given range. """ parser = FloatParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) _RegisterBoundsValidatorIfNeeded(parser, name, flag_values=flag_values) # # INTEGER FLAGS # class IntegerParser(NumericParser): """Parser of an integer value. Parsed value may be bounded to a given upper and lower bound. """ number_article = "an" number_name = "integer" syntactic_help = " ".join((number_article, number_name)) def __init__(self, lower_bound=None, upper_bound=None): super(IntegerParser, self).__init__() self.lower_bound = lower_bound self.upper_bound = upper_bound sh = self.syntactic_help if lower_bound is not None and upper_bound is not None: sh = ("%s in the range [%s, %s]" % (sh, lower_bound, upper_bound)) elif lower_bound == 1: sh = "a positive %s" % self.number_name elif upper_bound == -1: sh = "a negative %s" % self.number_name elif lower_bound == 0: sh = "a non-negative %s" % self.number_name elif upper_bound == 0: sh = "a non-positive %s" % self.number_name elif upper_bound is not None: sh = "%s <= %s" % (self.number_name, upper_bound) elif lower_bound is not None: sh = "%s >= %s" % (self.number_name, lower_bound) self.syntactic_help = sh def Convert(self, argument): __pychecker__ = 'no-returnvalues' if type(argument) == str: base = 10 if len(argument) > 2 and argument[0] == "0" and argument[1] == "x": base = 16 try: return int(argument, base) # ValueError is thrown when argument is a string, and overflows an int. except ValueError: return long(argument, base) else: try: return int(argument) # OverflowError is thrown when argument is numeric, and overflows an int. except OverflowError: return long(argument) def Type(self): return 'int' def DEFINE_integer(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value must be an integer. If lower_bound, or upper_bound are set, then this flag must be within the given range. """ parser = IntegerParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) _RegisterBoundsValidatorIfNeeded(parser, name, flag_values=flag_values) # # ENUM FLAGS # class EnumParser(ArgumentParser): """Parser of a string enum value (a string value from a given set). If enum_values (see below) is not specified, any string is allowed. """ def __init__(self, enum_values=None): super(EnumParser, self).__init__() self.enum_values = enum_values def Parse(self, argument): if self.enum_values and argument not in self.enum_values: raise ValueError("value should be one of <%s>" % "|".join(self.enum_values)) return argument def Type(self): return 'string enum' class EnumFlag(Flag): """Basic enum flag; its value can be any string from list of enum_values.""" def __init__(self, name, default, help, enum_values=None, short_name=None, **args): enum_values = enum_values or [] p = EnumParser(enum_values) g = ArgumentSerializer() Flag.__init__(self, p, g, name, default, help, short_name, **args) if not self.help: self.help = "an enum string" self.help = "<%s>: %s" % ("|".join(enum_values), self.help) def _WriteCustomInfoInXMLFormat(self, outfile, indent): for enum_value in self.parser.enum_values: _WriteSimpleXMLElement(outfile, 'enum_value', enum_value, indent) def DEFINE_enum(name, default, enum_values, help, flag_values=FLAGS, **args): """Registers a flag whose value can be any string from enum_values.""" DEFINE_flag(EnumFlag(name, default, help, enum_values, ** args), flag_values) # # LIST FLAGS # class BaseListParser(ArgumentParser): """Base class for a parser of lists of strings. To extend, inherit from this class; from the subclass __init__, call BaseListParser.__init__(self, token, name) where token is a character used to tokenize, and name is a description of the separator. """ def __init__(self, token=None, name=None): assert name super(BaseListParser, self).__init__() self._token = token self._name = name self.syntactic_help = "a %s separated list" % self._name def Parse(self, argument): if isinstance(argument, list): return argument elif argument == '': return [] else: return [s.strip() for s in argument.split(self._token)] def Type(self): return '%s separated list of strings' % self._name class ListParser(BaseListParser): """Parser for a comma-separated list of strings.""" def __init__(self): BaseListParser.__init__(self, ',', 'comma') def WriteCustomInfoInXMLFormat(self, outfile, indent): BaseListParser.WriteCustomInfoInXMLFormat(self, outfile, indent) _WriteSimpleXMLElement(outfile, 'list_separator', repr(','), indent) class WhitespaceSeparatedListParser(BaseListParser): """Parser for a whitespace-separated list of strings.""" def __init__(self): BaseListParser.__init__(self, None, 'whitespace') def WriteCustomInfoInXMLFormat(self, outfile, indent): BaseListParser.WriteCustomInfoInXMLFormat(self, outfile, indent) separators = list(string.whitespace) separators.sort() for ws_char in string.whitespace: _WriteSimpleXMLElement(outfile, 'list_separator', repr(ws_char), indent) def DEFINE_list(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value is a comma-separated list of strings.""" parser = ListParser() serializer = ListSerializer(',') DEFINE(parser, name, default, help, flag_values, serializer, **args) def DEFINE_spaceseplist(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value is a whitespace-separated list of strings. Any whitespace can be used as a separator. """ parser = WhitespaceSeparatedListParser() serializer = ListSerializer(' ') DEFINE(parser, name, default, help, flag_values, serializer, **args) # # MULTI FLAGS # class MultiFlag(Flag): """A flag that can appear multiple time on the command-line. The value of such a flag is a list that contains the individual values from all the appearances of that flag on the command-line. See the __doc__ for Flag for most behavior of this class. Only differences in behavior are described here: * The default value may be either a single value or a list of values. A single value is interpreted as the [value] singleton list. * The value of the flag is always a list, even if the option was only supplied once, and even if the default value is a single value """ def __init__(self, *args, **kwargs): Flag.__init__(self, *args, **kwargs) self.help += ';\n repeat this option to specify a list of values' def Parse(self, arguments): """Parses one or more arguments with the installed parser. Args: arguments: a single argument or a list of arguments (typically a list of default values); a single argument is converted internally into a list containing one item. """ if not isinstance(arguments, list): # Default value may be a list of values. Most other arguments # will not be, so convert them into a single-item list to make # processing simpler below. arguments = [arguments] if self.present: # keep a backup reference to list of previously supplied option values values = self.value else: # "erase" the defaults with an empty list values = [] for item in arguments: # have Flag superclass parse argument, overwriting self.value reference Flag.Parse(self, item) # also increments self.present values.append(self.value) # put list of option values back in the 'value' attribute self.value = values def Serialize(self): if not self.serializer: raise FlagsError("Serializer not present for flag %s" % self.name) if self.value is None: return '' s = '' multi_value = self.value for self.value in multi_value: if s: s += ' ' s += Flag.Serialize(self) self.value = multi_value return s def Type(self): return 'multi ' + self.parser.Type() def DEFINE_multi(parser, serializer, name, default, help, flag_values=FLAGS, **args): """Registers a generic MultiFlag that parses its args with a given parser. Auxiliary function. Normal users should NOT use it directly. Developers who need to create their own 'Parser' classes for options which can appear multiple times can call this module function to register their flags. """ DEFINE_flag(MultiFlag(parser, serializer, name, default, help, **args), flag_values) def DEFINE_multistring(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value can be a list of any strings. Use the flag on the command line multiple times to place multiple string values into the list. The 'default' may be a single string (which will be converted into a single-element list) or a list of strings. """ parser = ArgumentParser() serializer = ArgumentSerializer() DEFINE_multi(parser, serializer, name, default, help, flag_values, **args) def DEFINE_multi_int(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value can be a list of arbitrary integers. Use the flag on the command line multiple times to place multiple integer values into the list. The 'default' may be a single integer (which will be converted into a single-element list) or a list of integers. """ parser = IntegerParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE_multi(parser, serializer, name, default, help, flag_values, **args) # Now register the flags that we want to exist in all applications. # These are all defined with allow_override=1, so user-apps can use # these flagnames for their own purposes, if they want. DEFINE_flag(HelpFlag()) DEFINE_flag(HelpshortFlag()) DEFINE_flag(HelpXMLFlag()) # Define special flags here so that help may be generated for them. # NOTE: Please do NOT use _SPECIAL_FLAGS from outside this module. _SPECIAL_FLAGS = FlagValues() DEFINE_string( 'flagfile', "", "Insert flag definitions from the given file into the command line.", _SPECIAL_FLAGS) DEFINE_string( 'undefok', "", "comma-separated list of flag names that it is okay to specify " "on the command line even if the program does not define a flag " "with that name. IMPORTANT: flags in this list that have " "arguments MUST use the --flag=value format.", _SPECIAL_FLAGS)
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Simple command-line example for Google URL Shortener API. Command-line application that shortens a URL. """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' import gflags import httplib2 import logging import pprint import sys from apiclient.discovery import build from oauth2client.file import Storage from oauth2client.client import OAuth2WebServerFlow from oauth2client.tools import run FLAGS = gflags.FLAGS FLOW = OAuth2WebServerFlow( client_id='433807057907.apps.googleusercontent.com', client_secret='jigtZpMApkRxncxikFpR+SFg', scope='https://www.googleapis.com/auth/urlshortener', user_agent='urlshortener-cmdline-sample/1.0') gflags.DEFINE_enum('logging_level', 'ERROR', ['DEBUG', 'INFO', 'WARNING', 'ERROR', 'CRITICAL'], 'Set the level of logging detail.') def main(argv): try: argv = FLAGS(argv) except gflags.FlagsError, e: print '%s\\nUsage: %s ARGS\\n%s' % (e, argv[0], FLAGS) sys.exit(1) logging.getLogger().setLevel(getattr(logging, FLAGS.logging_level)) storage = Storage('urlshortener.dat') credentials = storage.get() if credentials is None or credentials.invalid == True: credentials = run(FLOW, storage) http = httplib2.Http() http = credentials.authorize(http) # Build the url shortener service service = build("urlshortener", "v1", http=http, developerKey="AIzaSyDRRpR3GS1F1_jKNNM9HCNd2wJQyPG3oN0") url = service.url() # Create a shortened URL by inserting the URL into the url collection. body = {"longUrl": "http://code.google.com/apis/urlshortener/" } resp = url.insert(body=body).execute() pprint.pprint(resp) shortUrl = resp['id'] # Convert the shortened URL back into a long URL resp = url.get(shortUrl=shortUrl).execute() pprint.pprint(resp) if __name__ == '__main__': main(sys.argv)
Python
#!/usr/bin/python2.4 # -*- coding: utf-8 -*- # # Copyright 2010 Google Inc. All Rights Reserved. """Simple command-line example for Google URL Shortener API. Command-line application that shortens a URL. """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' import gflags import httplib2 import logging import pprint import sys from apiclient.discovery import build from oauth2client.file import Storage from oauth2client.client import OAuth2WebServerFlow from oauth2client.tools import run FLAGS = gflags.FLAGS FLOW = OAuth2WebServerFlow( client_id='433807057907.apps.googleusercontent.com', client_secret='jigtZpMApkRxncxikFpR+SFg', scope='https://www.googleapis.com/auth/urlshortener', user_agent='urlshortener-cmdline-sample/1.0') gflags.DEFINE_enum('logging_level', 'ERROR', ['DEBUG', 'INFO', 'WARNING', 'ERROR', 'CRITICAL'], 'Set the level of logging detail.') def main(argv): try: argv = FLAGS(argv) except gflags.FlagsError, e: print '%s\\nUsage: %s ARGS\\n%s' % (e, argv[0], FLAGS) sys.exit(1) logging.getLogger().setLevel(getattr(logging, FLAGS.logging_level)) storage = Storage('urlshortener.dat') credentials = storage.get() if credentials is None or credentials.invalid == True: credentials = run(FLOW, storage) http = httplib2.Http() http = credentials.authorize(http) # Build the url shortener service service = build("urlshortener", "v1", http=http, developerKey="AIzaSyDRRpR3GS1F1_jKNNM9HCNd2wJQyPG3oN0") url = service.url() # Create a shortened URL by inserting the URL into the url collection. body = {"longUrl": "http://code.google.com/apis/urlshortener/" } resp = url.insert(body=body).execute() pprint.pprint(resp) shortUrl = resp['id'] # Convert the shortened URL back into a long URL resp = url.get(shortUrl=shortUrl).execute() pprint.pprint(resp) if __name__ == '__main__': main(sys.argv)
Python
#!/usr/bin/env python # # Copyright 2007 Google Inc. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. # __author__ = 'jcgregorio@google.com (Joe Gregorio)' import httplib2 import logging import os import pickle from apiclient.discovery import build from oauth2client.appengine import CredentialsProperty from oauth2client.appengine import StorageByKeyName from oauth2client.client import OAuth2WebServerFlow from google.appengine.api import memcache from google.appengine.api import users from google.appengine.ext import db from google.appengine.ext import webapp from google.appengine.ext.webapp import template from google.appengine.ext.webapp import util from google.appengine.ext.webapp.util import login_required class Credentials(db.Model): credentials = CredentialsProperty() class MainHandler(webapp.RequestHandler): @login_required def get(self): user = users.get_current_user() credentials = StorageByKeyName( Credentials, user.user_id(), 'credentials').get() if credentials is None or credentials.invalid == True: flow = OAuth2WebServerFlow( # Visit https://code.google.com/apis/console to # generate your client_id, client_secret and to # register your redirect_uri. client_id='<YOUR CLIENT ID HERE>', client_secret='<YOUR CLIENT SECRET HERE>', scope='https://www.googleapis.com/auth/buzz', user_agent='buzz-cmdline-sample/1.0', domain='anonymous', xoauth_displayname='Google App Engine Example App') callback = self.request.relative_url('/auth_return') authorize_url = flow.step1_get_authorize_url(callback) memcache.set(user.user_id(), pickle.dumps(flow)) self.redirect(authorize_url) else: http = httplib2.Http() http = credentials.authorize(http) service = build("buzz", "v1", http=http) activities = service.activities() activitylist = activities.list(scope='@consumption', userId='@me').execute() path = os.path.join(os.path.dirname(__file__), 'welcome.html') logout = users.create_logout_url('/') self.response.out.write( template.render( path, {'activitylist': activitylist, 'logout': logout })) class OAuthHandler(webapp.RequestHandler): @login_required def get(self): user = users.get_current_user() flow = pickle.loads(memcache.get(user.user_id())) if flow: credentials = flow.step2_exchange(self.request.params) StorageByKeyName( Credentials, user.user_id(), 'credentials').put(credentials) self.redirect("/") else: pass def main(): application = webapp.WSGIApplication( [ ('/', MainHandler), ('/auth_return', OAuthHandler) ], debug=True) util.run_wsgi_app(application) if __name__ == '__main__': main()
Python
#!/usr/bin/env python # Copyright (c) 2010, Google Inc. # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. """Module to enforce different constraints on flags. A validator represents an invariant, enforced over a one or more flags. See 'FLAGS VALIDATORS' in flags.py's docstring for a usage manual. """ __author__ = 'olexiy@google.com (Olexiy Oryeshko)' class Error(Exception): """Thrown If validator constraint is not satisfied.""" class Validator(object): """Base class for flags validators. Users should NOT overload these classes, and use flags.Register... methods instead. """ # Used to assign each validator an unique insertion_index validators_count = 0 def __init__(self, checker, message): """Constructor to create all validators. Args: checker: function to verify the constraint. Input of this method varies, see SimpleValidator and DictionaryValidator for a detailed description. message: string, error message to be shown to the user """ self.checker = checker self.message = message Validator.validators_count += 1 # Used to assert validators in the order they were registered (CL/18694236) self.insertion_index = Validator.validators_count def Verify(self, flag_values): """Verify that constraint is satisfied. flags library calls this method to verify Validator's constraint. Args: flag_values: flags.FlagValues, containing all flags Raises: Error: if constraint is not satisfied. """ param = self._GetInputToCheckerFunction(flag_values) if not self.checker(param): raise Error(self.message) def GetFlagsNames(self): """Return the names of the flags checked by this validator. Returns: [string], names of the flags """ raise NotImplementedError('This method should be overloaded') def PrintFlagsWithValues(self, flag_values): raise NotImplementedError('This method should be overloaded') def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues, containing all flags. Returns: Return type depends on the specific validator. """ raise NotImplementedError('This method should be overloaded') class SimpleValidator(Validator): """Validator behind RegisterValidator() method. Validates that a single flag passes its checker function. The checker function takes the flag value and returns True (if value looks fine) or, if flag value is not valid, either returns False or raises an Exception.""" def __init__(self, flag_name, checker, message): """Constructor. Args: flag_name: string, name of the flag. checker: function to verify the validator. input - value of the corresponding flag (string, boolean, etc). output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise Error. message: string, error message to be shown to the user if validator's condition is not satisfied """ super(SimpleValidator, self).__init__(checker, message) self.flag_name = flag_name def GetFlagsNames(self): return [self.flag_name] def PrintFlagsWithValues(self, flag_values): return 'flag --%s=%s' % (self.flag_name, flag_values[self.flag_name].value) def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues Returns: value of the corresponding flag. """ return flag_values[self.flag_name].value class DictionaryValidator(Validator): """Validator behind RegisterDictionaryValidator method. Validates that flag values pass their common checker function. The checker function takes flag values and returns True (if values look fine) or, if values are not valid, either returns False or raises an Exception. """ def __init__(self, flag_names, checker, message): """Constructor. Args: flag_names: [string], containing names of the flags used by checker. checker: function to verify the validator. input - dictionary, with keys() being flag_names, and value for each key being the value of the corresponding flag (string, boolean, etc). output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise Error. message: string, error message to be shown to the user if validator's condition is not satisfied """ super(DictionaryValidator, self).__init__(checker, message) self.flag_names = flag_names def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues Returns: dictionary, with keys() being self.lag_names, and value for each key being the value of the corresponding flag (string, boolean, etc). """ return dict([key, flag_values[key].value] for key in self.flag_names) def PrintFlagsWithValues(self, flag_values): prefix = 'flags ' flags_with_values = [] for key in self.flag_names: flags_with_values.append('%s=%s' % (key, flag_values[key].value)) return prefix + ', '.join(flags_with_values) def GetFlagsNames(self): return self.flag_names
Python
#!/usr/bin/env python # # Copyright 2007 Google Inc. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. # __author__ = 'jcgregorio@google.com (Joe Gregorio)' import httplib2 import logging import os import pickle from apiclient.discovery import build from oauth2client.appengine import CredentialsProperty from oauth2client.appengine import StorageByKeyName from oauth2client.client import OAuth2WebServerFlow from google.appengine.api import memcache from google.appengine.api import users from google.appengine.ext import db from google.appengine.ext import webapp from google.appengine.ext.webapp import template from google.appengine.ext.webapp import util from google.appengine.ext.webapp.util import login_required class Credentials(db.Model): credentials = CredentialsProperty() class MainHandler(webapp.RequestHandler): @login_required def get(self): user = users.get_current_user() credentials = StorageByKeyName( Credentials, user.user_id(), 'credentials').get() if credentials is None or credentials.invalid == True: flow = OAuth2WebServerFlow( # Visit https://code.google.com/apis/console to # generate your client_id, client_secret and to # register your redirect_uri. client_id='<YOUR CLIENT ID HERE>', client_secret='<YOUR CLIENT SECRET HERE>', scope='https://www.googleapis.com/auth/buzz', user_agent='buzz-cmdline-sample/1.0', domain='anonymous', xoauth_displayname='Google App Engine Example App') callback = self.request.relative_url('/auth_return') authorize_url = flow.step1_get_authorize_url(callback) memcache.set(user.user_id(), pickle.dumps(flow)) self.redirect(authorize_url) else: http = httplib2.Http() http = credentials.authorize(http) service = build("buzz", "v1", http=http) activities = service.activities() activitylist = activities.list(scope='@consumption', userId='@me').execute() path = os.path.join(os.path.dirname(__file__), 'welcome.html') logout = users.create_logout_url('/') self.response.out.write( template.render( path, {'activitylist': activitylist, 'logout': logout })) class OAuthHandler(webapp.RequestHandler): @login_required def get(self): user = users.get_current_user() flow = pickle.loads(memcache.get(user.user_id())) if flow: credentials = flow.step2_exchange(self.request.params) StorageByKeyName( Credentials, user.user_id(), 'credentials').put(credentials) self.redirect("/") else: pass def main(): application = webapp.WSGIApplication( [ ('/', MainHandler), ('/auth_return', OAuthHandler) ], debug=True) util.run_wsgi_app(application) if __name__ == '__main__': main()
Python
#!/usr/bin/env python # Copyright (c) 2007, Google Inc. # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. # # --- # Author: Chad Lester # Design and style contributions by: # Amit Patel, Bogdan Cocosel, Daniel Dulitz, Eric Tiedemann, # Eric Veach, Laurence Gonsalves, Matthew Springer # Code reorganized a bit by Craig Silverstein """This module is used to define and parse command line flags. This module defines a *distributed* flag-definition policy: rather than an application having to define all flags in or near main(), each python module defines flags that are useful to it. When one python module imports another, it gains access to the other's flags. (This is implemented by having all modules share a common, global registry object containing all the flag information.) Flags are defined through the use of one of the DEFINE_xxx functions. The specific function used determines how the flag is parsed, checked, and optionally type-converted, when it's seen on the command line. IMPLEMENTATION: DEFINE_* creates a 'Flag' object and registers it with a 'FlagValues' object (typically the global FlagValues FLAGS, defined here). The 'FlagValues' object can scan the command line arguments and pass flag arguments to the corresponding 'Flag' objects for value-checking and type conversion. The converted flag values are available as attributes of the 'FlagValues' object. Code can access the flag through a FlagValues object, for instance gflags.FLAGS.myflag. Typically, the __main__ module passes the command line arguments to gflags.FLAGS for parsing. At bottom, this module calls getopt(), so getopt functionality is supported, including short- and long-style flags, and the use of -- to terminate flags. Methods defined by the flag module will throw 'FlagsError' exceptions. The exception argument will be a human-readable string. FLAG TYPES: This is a list of the DEFINE_*'s that you can do. All flags take a name, default value, help-string, and optional 'short' name (one-letter name). Some flags have other arguments, which are described with the flag. DEFINE_string: takes any input, and interprets it as a string. DEFINE_bool or DEFINE_boolean: typically does not take an argument: say --myflag to set FLAGS.myflag to true, or --nomyflag to set FLAGS.myflag to false. Alternately, you can say --myflag=true or --myflag=t or --myflag=1 or --myflag=false or --myflag=f or --myflag=0 DEFINE_float: takes an input and interprets it as a floating point number. Takes optional args lower_bound and upper_bound; if the number specified on the command line is out of range, it will raise a FlagError. DEFINE_integer: takes an input and interprets it as an integer. Takes optional args lower_bound and upper_bound as for floats. DEFINE_enum: takes a list of strings which represents legal values. If the command-line value is not in this list, raise a flag error. Otherwise, assign to FLAGS.flag as a string. DEFINE_list: Takes a comma-separated list of strings on the commandline. Stores them in a python list object. DEFINE_spaceseplist: Takes a space-separated list of strings on the commandline. Stores them in a python list object. Example: --myspacesepflag "foo bar baz" DEFINE_multistring: The same as DEFINE_string, except the flag can be specified more than once on the commandline. The result is a python list object (list of strings), even if the flag is only on the command line once. DEFINE_multi_int: The same as DEFINE_integer, except the flag can be specified more than once on the commandline. The result is a python list object (list of ints), even if the flag is only on the command line once. SPECIAL FLAGS: There are a few flags that have special meaning: --help prints a list of all the flags in a human-readable fashion --helpshort prints a list of all key flags (see below). --helpxml prints a list of all flags, in XML format. DO NOT parse the output of --help and --helpshort. Instead, parse the output of --helpxml. For more info, see "OUTPUT FOR --helpxml" below. --flagfile=foo read flags from file foo. --undefok=f1,f2 ignore unrecognized option errors for f1,f2. For boolean flags, you should use --undefok=boolflag, and --boolflag and --noboolflag will be accepted. Do not use --undefok=noboolflag. -- as in getopt(), terminates flag-processing FLAGS VALIDATORS: If your program: - requires flag X to be specified - needs flag Y to match a regular expression - or requires any more general constraint to be satisfied then validators are for you! Each validator represents a constraint over one flag, which is enforced starting from the initial parsing of the flags and until the program terminates. Also, lower_bound and upper_bound for numerical flags are enforced using flag validators. Howto: If you want to enforce a constraint over one flag, use flags.RegisterValidator(flag_name, checker, message='Flag validation failed', flag_values=FLAGS) After flag values are initially parsed, and after any change to the specified flag, method checker(flag_value) will be executed. If constraint is not satisfied, an IllegalFlagValue exception will be raised. See RegisterValidator's docstring for a detailed explanation on how to construct your own checker. EXAMPLE USAGE: FLAGS = flags.FLAGS flags.DEFINE_integer('my_version', 0, 'Version number.') flags.DEFINE_string('filename', None, 'Input file name', short_name='f') flags.RegisterValidator('my_version', lambda value: value % 2 == 0, message='--my_version must be divisible by 2') flags.MarkFlagAsRequired('filename') NOTE ON --flagfile: Flags may be loaded from text files in addition to being specified on the commandline. Any flags you don't feel like typing, throw them in a file, one flag per line, for instance: --myflag=myvalue --nomyboolean_flag You then specify your file with the special flag '--flagfile=somefile'. You CAN recursively nest flagfile= tokens OR use multiple files on the command line. Lines beginning with a single hash '#' or a double slash '//' are comments in your flagfile. Any flagfile=<file> will be interpreted as having a relative path from the current working directory rather than from the place the file was included from: myPythonScript.py --flagfile=config/somefile.cfg If somefile.cfg includes further --flagfile= directives, these will be referenced relative to the original CWD, not from the directory the including flagfile was found in! The caveat applies to people who are including a series of nested files in a different dir than they are executing out of. Relative path names are always from CWD, not from the directory of the parent include flagfile. We do now support '~' expanded directory names. Absolute path names ALWAYS work! EXAMPLE USAGE: import gflags FLAGS = gflags.FLAGS # Flag names are globally defined! So in general, we need to be # careful to pick names that are unlikely to be used by other libraries. # If there is a conflict, we'll get an error at import time. gflags.DEFINE_string('name', 'Mr. President', 'your name') gflags.DEFINE_integer('age', None, 'your age in years', lower_bound=0) gflags.DEFINE_boolean('debug', False, 'produces debugging output') gflags.DEFINE_enum('gender', 'male', ['male', 'female'], 'your gender') def main(argv): try: argv = FLAGS(argv) # parse flags except gflags.FlagsError, e: print '%s\\nUsage: %s ARGS\\n%s' % (e, sys.argv[0], FLAGS) sys.exit(1) if FLAGS.debug: print 'non-flag arguments:', argv print 'Happy Birthday', FLAGS.name if FLAGS.age is not None: print 'You are a %s, who is %d years old' % (FLAGS.gender, FLAGS.age) if __name__ == '__main__': main(sys.argv) KEY FLAGS: As we already explained, each module gains access to all flags defined by all the other modules it transitively imports. In the case of non-trivial scripts, this means a lot of flags ... For documentation purposes, it is good to identify the flags that are key (i.e., really important) to a module. Clearly, the concept of "key flag" is a subjective one. When trying to determine whether a flag is key to a module or not, assume that you are trying to explain your module to a potential user: which flags would you really like to mention first? We'll describe shortly how to declare which flags are key to a module. For the moment, assume we know the set of key flags for each module. Then, if you use the app.py module, you can use the --helpshort flag to print only the help for the flags that are key to the main module, in a human-readable format. NOTE: If you need to parse the flag help, do NOT use the output of --help / --helpshort. That output is meant for human consumption, and may be changed in the future. Instead, use --helpxml; flags that are key for the main module are marked there with a <key>yes</key> element. The set of key flags for a module M is composed of: 1. Flags defined by module M by calling a DEFINE_* function. 2. Flags that module M explictly declares as key by using the function DECLARE_key_flag(<flag_name>) 3. Key flags of other modules that M specifies by using the function ADOPT_module_key_flags(<other_module>) This is a "bulk" declaration of key flags: each flag that is key for <other_module> becomes key for the current module too. Notice that if you do not use the functions described at points 2 and 3 above, then --helpshort prints information only about the flags defined by the main module of our script. In many cases, this behavior is good enough. But if you move part of the main module code (together with the related flags) into a different module, then it is nice to use DECLARE_key_flag / ADOPT_module_key_flags and make sure --helpshort lists all relevant flags (otherwise, your code refactoring may confuse your users). Note: each of DECLARE_key_flag / ADOPT_module_key_flags has its own pluses and minuses: DECLARE_key_flag is more targeted and may lead a more focused --helpshort documentation. ADOPT_module_key_flags is good for cases when an entire module is considered key to the current script. Also, it does not require updates to client scripts when a new flag is added to the module. EXAMPLE USAGE 2 (WITH KEY FLAGS): Consider an application that contains the following three files (two auxiliary modules and a main module): File libfoo.py: import gflags gflags.DEFINE_integer('num_replicas', 3, 'Number of replicas to start') gflags.DEFINE_boolean('rpc2', True, 'Turn on the usage of RPC2.') ... some code ... File libbar.py: import gflags gflags.DEFINE_string('bar_gfs_path', '/gfs/path', 'Path to the GFS files for libbar.') gflags.DEFINE_string('email_for_bar_errors', 'bar-team@google.com', 'Email address for bug reports about module libbar.') gflags.DEFINE_boolean('bar_risky_hack', False, 'Turn on an experimental and buggy optimization.') ... some code ... File myscript.py: import gflags import libfoo import libbar gflags.DEFINE_integer('num_iterations', 0, 'Number of iterations.') # Declare that all flags that are key for libfoo are # key for this module too. gflags.ADOPT_module_key_flags(libfoo) # Declare that the flag --bar_gfs_path (defined in libbar) is key # for this module. gflags.DECLARE_key_flag('bar_gfs_path') ... some code ... When myscript is invoked with the flag --helpshort, the resulted help message lists information about all the key flags for myscript: --num_iterations, --num_replicas, --rpc2, and --bar_gfs_path (in addition to the special flags --help and --helpshort). Of course, myscript uses all the flags declared by it (in this case, just --num_replicas) or by any of the modules it transitively imports (e.g., the modules libfoo, libbar). E.g., it can access the value of FLAGS.bar_risky_hack, even if --bar_risky_hack is not declared as a key flag for myscript. OUTPUT FOR --helpxml: The --helpxml flag generates output with the following structure: <?xml version="1.0"?> <AllFlags> <program>PROGRAM_BASENAME</program> <usage>MAIN_MODULE_DOCSTRING</usage> (<flag> [<key>yes</key>] <file>DECLARING_MODULE</file> <name>FLAG_NAME</name> <meaning>FLAG_HELP_MESSAGE</meaning> <default>DEFAULT_FLAG_VALUE</default> <current>CURRENT_FLAG_VALUE</current> <type>FLAG_TYPE</type> [OPTIONAL_ELEMENTS] </flag>)* </AllFlags> Notes: 1. The output is intentionally similar to the output generated by the C++ command-line flag library. The few differences are due to the Python flags that do not have a C++ equivalent (at least not yet), e.g., DEFINE_list. 2. New XML elements may be added in the future. 3. DEFAULT_FLAG_VALUE is in serialized form, i.e., the string you can pass for this flag on the command-line. E.g., for a flag defined using DEFINE_list, this field may be foo,bar, not ['foo', 'bar']. 4. CURRENT_FLAG_VALUE is produced using str(). This means that the string 'false' will be represented in the same way as the boolean False. Using repr() would have removed this ambiguity and simplified parsing, but would have broken the compatibility with the C++ command-line flags. 5. OPTIONAL_ELEMENTS describe elements relevant for certain kinds of flags: lower_bound, upper_bound (for flags that specify bounds), enum_value (for enum flags), list_separator (for flags that consist of a list of values, separated by a special token). 6. We do not provide any example here: please use --helpxml instead. """ import cgi import getopt import os import re import string import sys import gflags_validators # Are we running at least python 2.2? try: if tuple(sys.version_info[:3]) < (2,2,0): raise NotImplementedError("requires python 2.2.0 or later") except AttributeError: # a very old python, that lacks sys.version_info raise NotImplementedError("requires python 2.2.0 or later") # If we're not running at least python 2.2.1, define True, False, and bool. # Thanks, Guido, for the code. try: True, False, bool except NameError: False = 0 True = 1 def bool(x): if x: return True else: return False # Are we running under pychecker? _RUNNING_PYCHECKER = 'pychecker.python' in sys.modules def _GetCallingModule(): """Returns the name of the module that's calling into this module. We generally use this function to get the name of the module calling a DEFINE_foo... function. """ # Walk down the stack to find the first globals dict that's not ours. for depth in range(1, sys.getrecursionlimit()): if not sys._getframe(depth).f_globals is globals(): globals_for_frame = sys._getframe(depth).f_globals module_name = _GetModuleObjectAndName(globals_for_frame)[1] if module_name is not None: return module_name raise AssertionError("No module was found") def _GetThisModuleObjectAndName(): """Returns: (module object, module name) for this module.""" return _GetModuleObjectAndName(globals()) # module exceptions: class FlagsError(Exception): """The base class for all flags errors.""" pass class DuplicateFlag(FlagsError): """Raised if there is a flag naming conflict.""" pass class DuplicateFlagCannotPropagateNoneToSwig(DuplicateFlag): """Special case of DuplicateFlag -- SWIG flag value can't be set to None. This can be raised when a duplicate flag is created. Even if allow_override is True, we still abort if the new value is None, because it's currently impossible to pass None default value back to SWIG. See FlagValues.SetDefault for details. """ pass # A DuplicateFlagError conveys more information than a # DuplicateFlag. Since there are external modules that create # DuplicateFlags, the interface to DuplicateFlag shouldn't change. class DuplicateFlagError(DuplicateFlag): def __init__(self, flagname, flag_values): self.flagname = flagname message = "The flag '%s' is defined twice." % self.flagname flags_by_module = flag_values.FlagsByModuleDict() for module in flags_by_module: for flag in flags_by_module[module]: if flag.name == flagname or flag.short_name == flagname: message = message + " First from " + module + "," break message = message + " Second from " + _GetCallingModule() DuplicateFlag.__init__(self, message) class IllegalFlagValue(FlagsError): """The flag command line argument is illegal.""" pass class UnrecognizedFlag(FlagsError): """Raised if a flag is unrecognized.""" pass # An UnrecognizedFlagError conveys more information than an UnrecognizedFlag. # Since there are external modules that create DuplicateFlags, the interface to # DuplicateFlag shouldn't change. The flagvalue will be assigned the full value # of the flag and its argument, if any, allowing handling of unrecognzed flags # in an exception handler. # If flagvalue is the empty string, then this exception is an due to a # reference to a flag that was not already defined. class UnrecognizedFlagError(UnrecognizedFlag): def __init__(self, flagname, flagvalue=''): self.flagname = flagname self.flagvalue = flagvalue UnrecognizedFlag.__init__( self, "Unknown command line flag '%s'" % flagname) # Global variable used by expvar _exported_flags = {} _help_width = 80 # width of help output def GetHelpWidth(): """Returns: an integer, the width of help lines that is used in TextWrap.""" return _help_width def CutCommonSpacePrefix(text): """Removes a common space prefix from the lines of a multiline text. If the first line does not start with a space, it is left as it is and only in the remaining lines a common space prefix is being searched for. That means the first line will stay untouched. This is especially useful to turn doc strings into help texts. This is because some people prefer to have the doc comment start already after the apostrophy and then align the following lines while others have the apostrophies on a seperately line. The function also drops trailing empty lines and ignores empty lines following the initial content line while calculating the initial common whitespace. Args: text: text to work on Returns: the resulting text """ text_lines = text.splitlines() # Drop trailing empty lines while text_lines and not text_lines[-1]: text_lines = text_lines[:-1] if text_lines: # We got some content, is the first line starting with a space? if text_lines[0] and text_lines[0][0].isspace(): text_first_line = [] else: text_first_line = [text_lines.pop(0)] # Calculate length of common leading whitesppace (only over content lines) common_prefix = os.path.commonprefix([line for line in text_lines if line]) space_prefix_len = len(common_prefix) - len(common_prefix.lstrip()) # If we have a common space prefix, drop it from all lines if space_prefix_len: for index in xrange(len(text_lines)): if text_lines[index]: text_lines[index] = text_lines[index][space_prefix_len:] return '\n'.join(text_first_line + text_lines) return '' def TextWrap(text, length=None, indent='', firstline_indent=None, tabs=' '): """Wraps a given text to a maximum line length and returns it. We turn lines that only contain whitespaces into empty lines. We keep new lines and tabs (e.g., we do not treat tabs as spaces). Args: text: text to wrap length: maximum length of a line, includes indentation if this is None then use GetHelpWidth() indent: indent for all but first line firstline_indent: indent for first line; if None, fall back to indent tabs: replacement for tabs Returns: wrapped text Raises: FlagsError: if indent not shorter than length FlagsError: if firstline_indent not shorter than length """ # Get defaults where callee used None if length is None: length = GetHelpWidth() if indent is None: indent = '' if len(indent) >= length: raise FlagsError('Indent must be shorter than length') # In line we will be holding the current line which is to be started # with indent (or firstline_indent if available) and then appended # with words. if firstline_indent is None: firstline_indent = '' line = indent else: line = firstline_indent if len(firstline_indent) >= length: raise FlagsError('First iline indent must be shorter than length') # If the callee does not care about tabs we simply convert them to # spaces If callee wanted tabs to be single space then we do that # already here. if not tabs or tabs == ' ': text = text.replace('\t', ' ') else: tabs_are_whitespace = not tabs.strip() line_regex = re.compile('([ ]*)(\t*)([^ \t]+)', re.MULTILINE) # Split the text into lines and the lines with the regex above. The # resulting lines are collected in result[]. For each split we get the # spaces, the tabs and the next non white space (e.g. next word). result = [] for text_line in text.splitlines(): # Store result length so we can find out whether processing the next # line gave any new content old_result_len = len(result) # Process next line with line_regex. For optimization we do an rstrip(). # - process tabs (changes either line or word, see below) # - process word (first try to squeeze on line, then wrap or force wrap) # Spaces found on the line are ignored, they get added while wrapping as # needed. for spaces, current_tabs, word in line_regex.findall(text_line.rstrip()): # If tabs weren't converted to spaces, handle them now if current_tabs: # If the last thing we added was a space anyway then drop # it. But let's not get rid of the indentation. if (((result and line != indent) or (not result and line != firstline_indent)) and line[-1] == ' '): line = line[:-1] # Add the tabs, if that means adding whitespace, just add it at # the line, the rstrip() code while shorten the line down if # necessary if tabs_are_whitespace: line += tabs * len(current_tabs) else: # if not all tab replacement is whitespace we prepend it to the word word = tabs * len(current_tabs) + word # Handle the case where word cannot be squeezed onto current last line if len(line) + len(word) > length and len(indent) + len(word) <= length: result.append(line.rstrip()) line = indent + word word = '' # No space left on line or can we append a space? if len(line) + 1 >= length: result.append(line.rstrip()) line = indent else: line += ' ' # Add word and shorten it up to allowed line length. Restart next # line with indent and repeat, or add a space if we're done (word # finished) This deals with words that caanot fit on one line # (e.g. indent + word longer than allowed line length). while len(line) + len(word) >= length: line += word result.append(line[:length]) word = line[length:] line = indent # Default case, simply append the word and a space if word: line += word + ' ' # End of input line. If we have content we finish the line. If the # current line is just the indent but we had content in during this # original line then we need to add an emoty line. if (result and line != indent) or (not result and line != firstline_indent): result.append(line.rstrip()) elif len(result) == old_result_len: result.append('') line = indent return '\n'.join(result) def DocToHelp(doc): """Takes a __doc__ string and reformats it as help.""" # Get rid of starting and ending white space. Using lstrip() or even # strip() could drop more than maximum of first line and right space # of last line. doc = doc.strip() # Get rid of all empty lines whitespace_only_line = re.compile('^[ \t]+$', re.M) doc = whitespace_only_line.sub('', doc) # Cut out common space at line beginnings doc = CutCommonSpacePrefix(doc) # Just like this module's comment, comments tend to be aligned somehow. # In other words they all start with the same amount of white space # 1) keep double new lines # 2) keep ws after new lines if not empty line # 3) all other new lines shall be changed to a space # Solution: Match new lines between non white space and replace with space. doc = re.sub('(?<=\S)\n(?=\S)', ' ', doc, re.M) return doc def _GetModuleObjectAndName(globals_dict): """Returns the module that defines a global environment, and its name. Args: globals_dict: A dictionary that should correspond to an environment providing the values of the globals. Returns: A pair consisting of (1) module object and (2) module name (a string). Returns (None, None) if the module could not be identified. """ # The use of .items() (instead of .iteritems()) is NOT a mistake: if # a parallel thread imports a module while we iterate over # .iteritems() (not nice, but possible), we get a RuntimeError ... # Hence, we use the slightly slower but safer .items(). for name, module in sys.modules.items(): if getattr(module, '__dict__', None) is globals_dict: if name == '__main__': # Pick a more informative name for the main module. name = sys.argv[0] return (module, name) return (None, None) def _GetMainModule(): """Returns the name of the module from which execution started.""" for depth in range(1, sys.getrecursionlimit()): try: globals_of_main = sys._getframe(depth).f_globals except ValueError: return _GetModuleObjectAndName(globals_of_main)[1] raise AssertionError("No module was found") class FlagValues: """Registry of 'Flag' objects. A 'FlagValues' can then scan command line arguments, passing flag arguments through to the 'Flag' objects that it owns. It also provides easy access to the flag values. Typically only one 'FlagValues' object is needed by an application: gflags.FLAGS This class is heavily overloaded: 'Flag' objects are registered via __setitem__: FLAGS['longname'] = x # register a new flag The .value attribute of the registered 'Flag' objects can be accessed as attributes of this 'FlagValues' object, through __getattr__. Both the long and short name of the original 'Flag' objects can be used to access its value: FLAGS.longname # parsed flag value FLAGS.x # parsed flag value (short name) Command line arguments are scanned and passed to the registered 'Flag' objects through the __call__ method. Unparsed arguments, including argv[0] (e.g. the program name) are returned. argv = FLAGS(sys.argv) # scan command line arguments The original registered Flag objects can be retrieved through the use of the dictionary-like operator, __getitem__: x = FLAGS['longname'] # access the registered Flag object The str() operator of a 'FlagValues' object provides help for all of the registered 'Flag' objects. """ def __init__(self): # Since everything in this class is so heavily overloaded, the only # way of defining and using fields is to access __dict__ directly. # Dictionary: flag name (string) -> Flag object. self.__dict__['__flags'] = {} # Dictionary: module name (string) -> list of Flag objects that are defined # by that module. self.__dict__['__flags_by_module'] = {} # Dictionary: module name (string) -> list of Flag objects that are # key for that module. self.__dict__['__key_flags_by_module'] = {} # Set if we should use new style gnu_getopt rather than getopt when parsing # the args. Only possible with Python 2.3+ self.UseGnuGetOpt(False) def UseGnuGetOpt(self, use_gnu_getopt=True): self.__dict__['__use_gnu_getopt'] = use_gnu_getopt def IsGnuGetOpt(self): return self.__dict__['__use_gnu_getopt'] def FlagDict(self): return self.__dict__['__flags'] def FlagsByModuleDict(self): """Returns the dictionary of module_name -> list of defined flags. Returns: A dictionary. Its keys are module names (strings). Its values are lists of Flag objects. """ return self.__dict__['__flags_by_module'] def KeyFlagsByModuleDict(self): """Returns the dictionary of module_name -> list of key flags. Returns: A dictionary. Its keys are module names (strings). Its values are lists of Flag objects. """ return self.__dict__['__key_flags_by_module'] def _RegisterFlagByModule(self, module_name, flag): """Records the module that defines a specific flag. We keep track of which flag is defined by which module so that we can later sort the flags by module. Args: module_name: A string, the name of a Python module. flag: A Flag object, a flag that is key to the module. """ flags_by_module = self.FlagsByModuleDict() flags_by_module.setdefault(module_name, []).append(flag) def _RegisterKeyFlagForModule(self, module_name, flag): """Specifies that a flag is a key flag for a module. Args: module_name: A string, the name of a Python module. flag: A Flag object, a flag that is key to the module. """ key_flags_by_module = self.KeyFlagsByModuleDict() # The list of key flags for the module named module_name. key_flags = key_flags_by_module.setdefault(module_name, []) # Add flag, but avoid duplicates. if flag not in key_flags: key_flags.append(flag) def _GetFlagsDefinedByModule(self, module): """Returns the list of flags defined by a module. Args: module: A module object or a module name (a string). Returns: A new list of Flag objects. Caller may update this list as he wishes: none of those changes will affect the internals of this FlagValue object. """ if not isinstance(module, str): module = module.__name__ return list(self.FlagsByModuleDict().get(module, [])) def _GetKeyFlagsForModule(self, module): """Returns the list of key flags for a module. Args: module: A module object or a module name (a string) Returns: A new list of Flag objects. Caller may update this list as he wishes: none of those changes will affect the internals of this FlagValue object. """ if not isinstance(module, str): module = module.__name__ # Any flag is a key flag for the module that defined it. NOTE: # key_flags is a fresh list: we can update it without affecting the # internals of this FlagValues object. key_flags = self._GetFlagsDefinedByModule(module) # Take into account flags explicitly declared as key for a module. for flag in self.KeyFlagsByModuleDict().get(module, []): if flag not in key_flags: key_flags.append(flag) return key_flags def AppendFlagValues(self, flag_values): """Appends flags registered in another FlagValues instance. Args: flag_values: registry to copy from """ for flag_name, flag in flag_values.FlagDict().iteritems(): # Each flags with shortname appears here twice (once under its # normal name, and again with its short name). To prevent # problems (DuplicateFlagError) with double flag registration, we # perform a check to make sure that the entry we're looking at is # for its normal name. if flag_name == flag.name: self[flag_name] = flag def RemoveFlagValues(self, flag_values): """Remove flags that were previously appended from another FlagValues. Args: flag_values: registry containing flags to remove. """ for flag_name in flag_values.FlagDict(): self.__delattr__(flag_name) def __setitem__(self, name, flag): """Registers a new flag variable.""" fl = self.FlagDict() if not isinstance(flag, Flag): raise IllegalFlagValue(flag) if not isinstance(name, type("")): raise FlagsError("Flag name must be a string") if len(name) == 0: raise FlagsError("Flag name cannot be empty") # If running under pychecker, duplicate keys are likely to be # defined. Disable check for duplicate keys when pycheck'ing. if (fl.has_key(name) and not flag.allow_override and not fl[name].allow_override and not _RUNNING_PYCHECKER): raise DuplicateFlagError(name, self) short_name = flag.short_name if short_name is not None: if (fl.has_key(short_name) and not flag.allow_override and not fl[short_name].allow_override and not _RUNNING_PYCHECKER): raise DuplicateFlagError(short_name, self) fl[short_name] = flag fl[name] = flag global _exported_flags _exported_flags[name] = flag def __getitem__(self, name): """Retrieves the Flag object for the flag --name.""" return self.FlagDict()[name] def __getattr__(self, name): """Retrieves the 'value' attribute of the flag --name.""" fl = self.FlagDict() if not fl.has_key(name): raise AttributeError(name) return fl[name].value def __setattr__(self, name, value): """Sets the 'value' attribute of the flag --name.""" fl = self.FlagDict() fl[name].value = value self._AssertValidators(fl[name].validators) return value def _AssertAllValidators(self): all_validators = set() for flag in self.FlagDict().itervalues(): for validator in flag.validators: all_validators.add(validator) self._AssertValidators(all_validators) def _AssertValidators(self, validators): """Assert if all validators in the list are satisfied. Asserts validators in the order they were created. Args: validators: Iterable(gflags_validators.Validator), validators to be verified Raises: AttributeError: if validators work with a non-existing flag. IllegalFlagValue: if validation fails for at least one validator """ for validator in sorted( validators, key=lambda validator: validator.insertion_index): try: validator.Verify(self) except gflags_validators.Error, e: message = validator.PrintFlagsWithValues(self) raise IllegalFlagValue('%s: %s' % (message, str(e))) def _FlagIsRegistered(self, flag_obj): """Checks whether a Flag object is registered under some name. Note: this is non trivial: in addition to its normal name, a flag may have a short name too. In self.FlagDict(), both the normal and the short name are mapped to the same flag object. E.g., calling only "del FLAGS.short_name" is not unregistering the corresponding Flag object (it is still registered under the longer name). Args: flag_obj: A Flag object. Returns: A boolean: True iff flag_obj is registered under some name. """ flag_dict = self.FlagDict() # Check whether flag_obj is registered under its long name. name = flag_obj.name if flag_dict.get(name, None) == flag_obj: return True # Check whether flag_obj is registered under its short name. short_name = flag_obj.short_name if (short_name is not None and flag_dict.get(short_name, None) == flag_obj): return True # The flag cannot be registered under any other name, so we do not # need to do a full search through the values of self.FlagDict(). return False def __delattr__(self, flag_name): """Deletes a previously-defined flag from a flag object. This method makes sure we can delete a flag by using del flag_values_object.<flag_name> E.g., flags.DEFINE_integer('foo', 1, 'Integer flag.') del flags.FLAGS.foo Args: flag_name: A string, the name of the flag to be deleted. Raises: AttributeError: When there is no registered flag named flag_name. """ fl = self.FlagDict() if flag_name not in fl: raise AttributeError(flag_name) flag_obj = fl[flag_name] del fl[flag_name] if not self._FlagIsRegistered(flag_obj): # If the Flag object indicated by flag_name is no longer # registered (please see the docstring of _FlagIsRegistered), then # we delete the occurences of the flag object in all our internal # dictionaries. self.__RemoveFlagFromDictByModule(self.FlagsByModuleDict(), flag_obj) self.__RemoveFlagFromDictByModule(self.KeyFlagsByModuleDict(), flag_obj) def __RemoveFlagFromDictByModule(self, flags_by_module_dict, flag_obj): """Removes a flag object from a module -> list of flags dictionary. Args: flags_by_module_dict: A dictionary that maps module names to lists of flags. flag_obj: A flag object. """ for unused_module, flags_in_module in flags_by_module_dict.iteritems(): # while (as opposed to if) takes care of multiple occurences of a # flag in the list for the same module. while flag_obj in flags_in_module: flags_in_module.remove(flag_obj) def SetDefault(self, name, value): """Changes the default value of the named flag object.""" fl = self.FlagDict() if not fl.has_key(name): raise AttributeError(name) fl[name].SetDefault(value) self._AssertValidators(fl[name].validators) def __contains__(self, name): """Returns True if name is a value (flag) in the dict.""" return name in self.FlagDict() has_key = __contains__ # a synonym for __contains__() def __iter__(self): return self.FlagDict().iterkeys() def __call__(self, argv): """Parses flags from argv; stores parsed flags into this FlagValues object. All unparsed arguments are returned. Flags are parsed using the GNU Program Argument Syntax Conventions, using getopt: http://www.gnu.org/software/libc/manual/html_mono/libc.html#Getopt Args: argv: argument list. Can be of any type that may be converted to a list. Returns: The list of arguments not parsed as options, including argv[0] Raises: FlagsError: on any parsing error """ # Support any sequence type that can be converted to a list argv = list(argv) shortopts = "" longopts = [] fl = self.FlagDict() # This pre parses the argv list for --flagfile=<> options. argv = argv[:1] + self.ReadFlagsFromFiles(argv[1:], force_gnu=False) # Correct the argv to support the google style of passing boolean # parameters. Boolean parameters may be passed by using --mybool, # --nomybool, --mybool=(true|false|1|0). getopt does not support # having options that may or may not have a parameter. We replace # instances of the short form --mybool and --nomybool with their # full forms: --mybool=(true|false). original_argv = list(argv) # list() makes a copy shortest_matches = None for name, flag in fl.items(): if not flag.boolean: continue if shortest_matches is None: # Determine the smallest allowable prefix for all flag names shortest_matches = self.ShortestUniquePrefixes(fl) no_name = 'no' + name prefix = shortest_matches[name] no_prefix = shortest_matches[no_name] # Replace all occurences of this boolean with extended forms for arg_idx in range(1, len(argv)): arg = argv[arg_idx] if arg.find('=') >= 0: continue if arg.startswith('--'+prefix) and ('--'+name).startswith(arg): argv[arg_idx] = ('--%s=true' % name) elif arg.startswith('--'+no_prefix) and ('--'+no_name).startswith(arg): argv[arg_idx] = ('--%s=false' % name) # Loop over all of the flags, building up the lists of short options # and long options that will be passed to getopt. Short options are # specified as a string of letters, each letter followed by a colon # if it takes an argument. Long options are stored in an array of # strings. Each string ends with an '=' if it takes an argument. for name, flag in fl.items(): longopts.append(name + "=") if len(name) == 1: # one-letter option: allow short flag type also shortopts += name if not flag.boolean: shortopts += ":" longopts.append('undefok=') undefok_flags = [] # In case --undefok is specified, loop to pick up unrecognized # options one by one. unrecognized_opts = [] args = argv[1:] while True: try: if self.__dict__['__use_gnu_getopt']: optlist, unparsed_args = getopt.gnu_getopt(args, shortopts, longopts) else: optlist, unparsed_args = getopt.getopt(args, shortopts, longopts) break except getopt.GetoptError, e: if not e.opt or e.opt in fl: # Not an unrecognized option, reraise the exception as a FlagsError raise FlagsError(e) # Remove offender from args and try again for arg_index in range(len(args)): if ((args[arg_index] == '--' + e.opt) or (args[arg_index] == '-' + e.opt) or (args[arg_index].startswith('--' + e.opt + '='))): unrecognized_opts.append((e.opt, args[arg_index])) args = args[0:arg_index] + args[arg_index+1:] break else: # We should have found the option, so we don't expect to get # here. We could assert, but raising the original exception # might work better. raise FlagsError(e) for name, arg in optlist: if name == '--undefok': flag_names = arg.split(',') undefok_flags.extend(flag_names) # For boolean flags, if --undefok=boolflag is specified, then we should # also accept --noboolflag, in addition to --boolflag. # Since we don't know the type of the undefok'd flag, this will affect # non-boolean flags as well. # NOTE: You shouldn't use --undefok=noboolflag, because then we will # accept --nonoboolflag here. We are choosing not to do the conversion # from noboolflag -> boolflag because of the ambiguity that flag names # can start with 'no'. undefok_flags.extend('no' + name for name in flag_names) continue if name.startswith('--'): # long option name = name[2:] short_option = 0 else: # short option name = name[1:] short_option = 1 if fl.has_key(name): flag = fl[name] if flag.boolean and short_option: arg = 1 flag.Parse(arg) # If there were unrecognized options, raise an exception unless # the options were named via --undefok. for opt, value in unrecognized_opts: if opt not in undefok_flags: raise UnrecognizedFlagError(opt, value) if unparsed_args: if self.__dict__['__use_gnu_getopt']: # if using gnu_getopt just return the program name + remainder of argv. ret_val = argv[:1] + unparsed_args else: # unparsed_args becomes the first non-flag detected by getopt to # the end of argv. Because argv may have been modified above, # return original_argv for this region. ret_val = argv[:1] + original_argv[-len(unparsed_args):] else: ret_val = argv[:1] self._AssertAllValidators() return ret_val def Reset(self): """Resets the values to the point before FLAGS(argv) was called.""" for f in self.FlagDict().values(): f.Unparse() def RegisteredFlags(self): """Returns: a list of the names and short names of all registered flags.""" return self.FlagDict().keys() def FlagValuesDict(self): """Returns: a dictionary that maps flag names to flag values.""" flag_values = {} for flag_name in self.RegisteredFlags(): flag = self.FlagDict()[flag_name] flag_values[flag_name] = flag.value return flag_values def __str__(self): """Generates a help string for all known flags.""" return self.GetHelp() def GetHelp(self, prefix=''): """Generates a help string for all known flags.""" helplist = [] flags_by_module = self.FlagsByModuleDict() if flags_by_module: modules = flags_by_module.keys() modules.sort() # Print the help for the main module first, if possible. main_module = _GetMainModule() if main_module in modules: modules.remove(main_module) modules = [main_module] + modules for module in modules: self.__RenderOurModuleFlags(module, helplist) self.__RenderModuleFlags('gflags', _SPECIAL_FLAGS.FlagDict().values(), helplist) else: # Just print one long list of flags. self.__RenderFlagList( self.FlagDict().values() + _SPECIAL_FLAGS.FlagDict().values(), helplist, prefix) return '\n'.join(helplist) def __RenderModuleFlags(self, module, flags, output_lines, prefix=""): """Generates a help string for a given module.""" if not isinstance(module, str): module = module.__name__ output_lines.append('\n%s%s:' % (prefix, module)) self.__RenderFlagList(flags, output_lines, prefix + " ") def __RenderOurModuleFlags(self, module, output_lines, prefix=""): """Generates a help string for a given module.""" flags = self._GetFlagsDefinedByModule(module) if flags: self.__RenderModuleFlags(module, flags, output_lines, prefix) def __RenderOurModuleKeyFlags(self, module, output_lines, prefix=""): """Generates a help string for the key flags of a given module. Args: module: A module object or a module name (a string). output_lines: A list of strings. The generated help message lines will be appended to this list. prefix: A string that is prepended to each generated help line. """ key_flags = self._GetKeyFlagsForModule(module) if key_flags: self.__RenderModuleFlags(module, key_flags, output_lines, prefix) def ModuleHelp(self, module): """Describe the key flags of a module. Args: module: A module object or a module name (a string). Returns: string describing the key flags of a module. """ helplist = [] self.__RenderOurModuleKeyFlags(module, helplist) return '\n'.join(helplist) def MainModuleHelp(self): """Describe the key flags of the main module. Returns: string describing the key flags of a module. """ return self.ModuleHelp(_GetMainModule()) def __RenderFlagList(self, flaglist, output_lines, prefix=" "): fl = self.FlagDict() special_fl = _SPECIAL_FLAGS.FlagDict() flaglist = [(flag.name, flag) for flag in flaglist] flaglist.sort() flagset = {} for (name, flag) in flaglist: # It's possible this flag got deleted or overridden since being # registered in the per-module flaglist. Check now against the # canonical source of current flag information, the FlagDict. if fl.get(name, None) != flag and special_fl.get(name, None) != flag: # a different flag is using this name now continue # only print help once if flagset.has_key(flag): continue flagset[flag] = 1 flaghelp = "" if flag.short_name: flaghelp += "-%s," % flag.short_name if flag.boolean: flaghelp += "--[no]%s" % flag.name + ":" else: flaghelp += "--%s" % flag.name + ":" flaghelp += " " if flag.help: flaghelp += flag.help flaghelp = TextWrap(flaghelp, indent=prefix+" ", firstline_indent=prefix) if flag.default_as_str: flaghelp += "\n" flaghelp += TextWrap("(default: %s)" % flag.default_as_str, indent=prefix+" ") if flag.parser.syntactic_help: flaghelp += "\n" flaghelp += TextWrap("(%s)" % flag.parser.syntactic_help, indent=prefix+" ") output_lines.append(flaghelp) def get(self, name, default): """Returns the value of a flag (if not None) or a default value. Args: name: A string, the name of a flag. default: Default value to use if the flag value is None. """ value = self.__getattr__(name) if value is not None: # Can't do if not value, b/c value might be '0' or "" return value else: return default def ShortestUniquePrefixes(self, fl): """Returns: dictionary; maps flag names to their shortest unique prefix.""" # Sort the list of flag names sorted_flags = [] for name, flag in fl.items(): sorted_flags.append(name) if flag.boolean: sorted_flags.append('no%s' % name) sorted_flags.sort() # For each name in the sorted list, determine the shortest unique # prefix by comparing itself to the next name and to the previous # name (the latter check uses cached info from the previous loop). shortest_matches = {} prev_idx = 0 for flag_idx in range(len(sorted_flags)): curr = sorted_flags[flag_idx] if flag_idx == (len(sorted_flags) - 1): next = None else: next = sorted_flags[flag_idx+1] next_len = len(next) for curr_idx in range(len(curr)): if (next is None or curr_idx >= next_len or curr[curr_idx] != next[curr_idx]): # curr longer than next or no more chars in common shortest_matches[curr] = curr[:max(prev_idx, curr_idx) + 1] prev_idx = curr_idx break else: # curr shorter than (or equal to) next shortest_matches[curr] = curr prev_idx = curr_idx + 1 # next will need at least one more char return shortest_matches def __IsFlagFileDirective(self, flag_string): """Checks whether flag_string contain a --flagfile=<foo> directive.""" if isinstance(flag_string, type("")): if flag_string.startswith('--flagfile='): return 1 elif flag_string == '--flagfile': return 1 elif flag_string.startswith('-flagfile='): return 1 elif flag_string == '-flagfile': return 1 else: return 0 return 0 def ExtractFilename(self, flagfile_str): """Returns filename from a flagfile_str of form -[-]flagfile=filename. The cases of --flagfile foo and -flagfile foo shouldn't be hitting this function, as they are dealt with in the level above this function. """ if flagfile_str.startswith('--flagfile='): return os.path.expanduser((flagfile_str[(len('--flagfile=')):]).strip()) elif flagfile_str.startswith('-flagfile='): return os.path.expanduser((flagfile_str[(len('-flagfile=')):]).strip()) else: raise FlagsError('Hit illegal --flagfile type: %s' % flagfile_str) def __GetFlagFileLines(self, filename, parsed_file_list): """Returns the useful (!=comments, etc) lines from a file with flags. Args: filename: A string, the name of the flag file. parsed_file_list: A list of the names of the files we have already read. MUTATED BY THIS FUNCTION. Returns: List of strings. See the note below. NOTE(springer): This function checks for a nested --flagfile=<foo> tag and handles the lower file recursively. It returns a list of all the lines that _could_ contain command flags. This is EVERYTHING except whitespace lines and comments (lines starting with '#' or '//'). """ line_list = [] # All line from flagfile. flag_line_list = [] # Subset of lines w/o comments, blanks, flagfile= tags. try: file_obj = open(filename, 'r') except IOError, e_msg: print e_msg print 'ERROR:: Unable to open flagfile: %s' % (filename) return flag_line_list line_list = file_obj.readlines() file_obj.close() parsed_file_list.append(filename) # This is where we check each line in the file we just read. for line in line_list: if line.isspace(): pass # Checks for comment (a line that starts with '#'). elif line.startswith('#') or line.startswith('//'): pass # Checks for a nested "--flagfile=<bar>" flag in the current file. # If we find one, recursively parse down into that file. elif self.__IsFlagFileDirective(line): sub_filename = self.ExtractFilename(line) # We do a little safety check for reparsing a file we've already done. if not sub_filename in parsed_file_list: included_flags = self.__GetFlagFileLines(sub_filename, parsed_file_list) flag_line_list.extend(included_flags) else: # Case of hitting a circularly included file. print >>sys.stderr, ('Warning: Hit circular flagfile dependency: %s' % sub_filename) else: # Any line that's not a comment or a nested flagfile should get # copied into 2nd position. This leaves earlier arguements # further back in the list, thus giving them higher priority. flag_line_list.append(line.strip()) return flag_line_list def ReadFlagsFromFiles(self, argv, force_gnu=True): """Processes command line args, but also allow args to be read from file. Args: argv: A list of strings, usually sys.argv[1:], which may contain one or more flagfile directives of the form --flagfile="./filename". Note that the name of the program (sys.argv[0]) should be omitted. force_gnu: If False, --flagfile parsing obeys normal flag semantics. If True, --flagfile parsing instead follows gnu_getopt semantics. *** WARNING *** force_gnu=False may become the future default! Returns: A new list which has the original list combined with what we read from any flagfile(s). References: Global gflags.FLAG class instance. This function should be called before the normal FLAGS(argv) call. This function scans the input list for a flag that looks like: --flagfile=<somefile>. Then it opens <somefile>, reads all valid key and value pairs and inserts them into the input list between the first item of the list and any subsequent items in the list. Note that your application's flags are still defined the usual way using gflags DEFINE_flag() type functions. Notes (assuming we're getting a commandline of some sort as our input): --> Flags from the command line argv _should_ always take precedence! --> A further "--flagfile=<otherfile.cfg>" CAN be nested in a flagfile. It will be processed after the parent flag file is done. --> For duplicate flags, first one we hit should "win". --> In a flagfile, a line beginning with # or // is a comment. --> Entirely blank lines _should_ be ignored. """ parsed_file_list = [] rest_of_args = argv new_argv = [] while rest_of_args: current_arg = rest_of_args[0] rest_of_args = rest_of_args[1:] if self.__IsFlagFileDirective(current_arg): # This handles the case of -(-)flagfile foo. In this case the # next arg really is part of this one. if current_arg == '--flagfile' or current_arg == '-flagfile': if not rest_of_args: raise IllegalFlagValue('--flagfile with no argument') flag_filename = os.path.expanduser(rest_of_args[0]) rest_of_args = rest_of_args[1:] else: # This handles the case of (-)-flagfile=foo. flag_filename = self.ExtractFilename(current_arg) new_argv[0:0] = self.__GetFlagFileLines(flag_filename, parsed_file_list) else: new_argv.append(current_arg) # Stop parsing after '--', like getopt and gnu_getopt. if current_arg == '--': break # Stop parsing after a non-flag, like getopt. if not current_arg.startswith('-'): if not force_gnu and not self.__dict__['__use_gnu_getopt']: break if rest_of_args: new_argv.extend(rest_of_args) return new_argv def FlagsIntoString(self): """Returns a string with the flags assignments from this FlagValues object. This function ignores flags whose value is None. Each flag assignment is separated by a newline. NOTE: MUST mirror the behavior of the C++ function CommandlineFlagsIntoString from google3/base/commandlineflags.cc. """ s = '' for flag in self.FlagDict().values(): if flag.value is not None: s += flag.Serialize() + '\n' return s def AppendFlagsIntoFile(self, filename): """Appends all flags assignments from this FlagInfo object to a file. Output will be in the format of a flagfile. NOTE: MUST mirror the behavior of the C++ version of AppendFlagsIntoFile from google3/base/commandlineflags.cc. """ out_file = open(filename, 'a') out_file.write(self.FlagsIntoString()) out_file.close() def WriteHelpInXMLFormat(self, outfile=None): """Outputs flag documentation in XML format. NOTE: We use element names that are consistent with those used by the C++ command-line flag library, from google3/base/commandlineflags_reporting.cc. We also use a few new elements (e.g., <key>), but we do not interfere / overlap with existing XML elements used by the C++ library. Please maintain this consistency. Args: outfile: File object we write to. Default None means sys.stdout. """ outfile = outfile or sys.stdout outfile.write('<?xml version=\"1.0\"?>\n') outfile.write('<AllFlags>\n') indent = ' ' _WriteSimpleXMLElement(outfile, 'program', os.path.basename(sys.argv[0]), indent) usage_doc = sys.modules['__main__'].__doc__ if not usage_doc: usage_doc = '\nUSAGE: %s [flags]\n' % sys.argv[0] else: usage_doc = usage_doc.replace('%s', sys.argv[0]) _WriteSimpleXMLElement(outfile, 'usage', usage_doc, indent) # Get list of key flags for the main module. key_flags = self._GetKeyFlagsForModule(_GetMainModule()) # Sort flags by declaring module name and next by flag name. flags_by_module = self.FlagsByModuleDict() all_module_names = list(flags_by_module.keys()) all_module_names.sort() for module_name in all_module_names: flag_list = [(f.name, f) for f in flags_by_module[module_name]] flag_list.sort() for unused_flag_name, flag in flag_list: is_key = flag in key_flags flag.WriteInfoInXMLFormat(outfile, module_name, is_key=is_key, indent=indent) outfile.write('</AllFlags>\n') outfile.flush() def AddValidator(self, validator): """Register new flags validator to be checked. Args: validator: gflags_validators.Validator Raises: AttributeError: if validators work with a non-existing flag. """ for flag_name in validator.GetFlagsNames(): flag = self.FlagDict()[flag_name] flag.validators.append(validator) # end of FlagValues definition # The global FlagValues instance FLAGS = FlagValues() def _MakeXMLSafe(s): """Escapes <, >, and & from s, and removes XML 1.0-illegal chars.""" s = cgi.escape(s) # Escape <, >, and & # Remove characters that cannot appear in an XML 1.0 document # (http://www.w3.org/TR/REC-xml/#charsets). # # NOTE: if there are problems with current solution, one may move to # XML 1.1, which allows such chars, if they're entity-escaped (&#xHH;). s = re.sub(r'[\x00-\x08\x0b\x0c\x0e-\x1f]', '', s) return s def _WriteSimpleXMLElement(outfile, name, value, indent): """Writes a simple XML element. Args: outfile: File object we write the XML element to. name: A string, the name of XML element. value: A Python object, whose string representation will be used as the value of the XML element. indent: A string, prepended to each line of generated output. """ value_str = str(value) if isinstance(value, bool): # Display boolean values as the C++ flag library does: no caps. value_str = value_str.lower() outfile.write('%s<%s>%s</%s>\n' % (indent, name, _MakeXMLSafe(value_str), name)) class Flag: """Information about a command-line flag. 'Flag' objects define the following fields: .name - the name for this flag .default - the default value for this flag .default_as_str - default value as repr'd string, e.g., "'true'" (or None) .value - the most recent parsed value of this flag; set by Parse() .help - a help string or None if no help is available .short_name - the single letter alias for this flag (or None) .boolean - if 'true', this flag does not accept arguments .present - true if this flag was parsed from command line flags. .parser - an ArgumentParser object .serializer - an ArgumentSerializer object .allow_override - the flag may be redefined without raising an error The only public method of a 'Flag' object is Parse(), but it is typically only called by a 'FlagValues' object. The Parse() method is a thin wrapper around the 'ArgumentParser' Parse() method. The parsed value is saved in .value, and the .present attribute is updated. If this flag was already present, a FlagsError is raised. Parse() is also called during __init__ to parse the default value and initialize the .value attribute. This enables other python modules to safely use flags even if the __main__ module neglects to parse the command line arguments. The .present attribute is cleared after __init__ parsing. If the default value is set to None, then the __init__ parsing step is skipped and the .value attribute is initialized to None. Note: The default value is also presented to the user in the help string, so it is important that it be a legal value for this flag. """ def __init__(self, parser, serializer, name, default, help_string, short_name=None, boolean=0, allow_override=0): self.name = name if not help_string: help_string = '(no help available)' self.help = help_string self.short_name = short_name self.boolean = boolean self.present = 0 self.parser = parser self.serializer = serializer self.allow_override = allow_override self.value = None self.validators = [] self.SetDefault(default) def __GetParsedValueAsString(self, value): if value is None: return None if self.serializer: return repr(self.serializer.Serialize(value)) if self.boolean: if value: return repr('true') else: return repr('false') return repr(str(value)) def Parse(self, argument): try: self.value = self.parser.Parse(argument) except ValueError, e: # recast ValueError as IllegalFlagValue raise IllegalFlagValue("flag --%s=%s: %s" % (self.name, argument, e)) self.present += 1 def Unparse(self): if self.default is None: self.value = None else: self.Parse(self.default) self.present = 0 def Serialize(self): if self.value is None: return '' if self.boolean: if self.value: return "--%s" % self.name else: return "--no%s" % self.name else: if not self.serializer: raise FlagsError("Serializer not present for flag %s" % self.name) return "--%s=%s" % (self.name, self.serializer.Serialize(self.value)) def SetDefault(self, value): """Changes the default value (and current value too) for this Flag.""" # We can't allow a None override because it may end up not being # passed to C++ code when we're overriding C++ flags. So we # cowardly bail out until someone fixes the semantics of trying to # pass None to a C++ flag. See swig_flags.Init() for details on # this behavior. # TODO(olexiy): Users can directly call this method, bypassing all flags # validators (we don't have FlagValues here, so we can not check # validators). # The simplest solution I see is to make this method private. # Another approach would be to store reference to the corresponding # FlagValues with each flag, but this seems to be an overkill. if value is None and self.allow_override: raise DuplicateFlagCannotPropagateNoneToSwig(self.name) self.default = value self.Unparse() self.default_as_str = self.__GetParsedValueAsString(self.value) def Type(self): """Returns: a string that describes the type of this Flag.""" # NOTE: we use strings, and not the types.*Type constants because # our flags can have more exotic types, e.g., 'comma separated list # of strings', 'whitespace separated list of strings', etc. return self.parser.Type() def WriteInfoInXMLFormat(self, outfile, module_name, is_key=False, indent=''): """Writes common info about this flag, in XML format. This is information that is relevant to all flags (e.g., name, meaning, etc.). If you defined a flag that has some other pieces of info, then please override _WriteCustomInfoInXMLFormat. Please do NOT override this method. Args: outfile: File object we write to. module_name: A string, the name of the module that defines this flag. is_key: A boolean, True iff this flag is key for main module. indent: A string that is prepended to each generated line. """ outfile.write(indent + '<flag>\n') inner_indent = indent + ' ' if is_key: _WriteSimpleXMLElement(outfile, 'key', 'yes', inner_indent) _WriteSimpleXMLElement(outfile, 'file', module_name, inner_indent) # Print flag features that are relevant for all flags. _WriteSimpleXMLElement(outfile, 'name', self.name, inner_indent) if self.short_name: _WriteSimpleXMLElement(outfile, 'short_name', self.short_name, inner_indent) if self.help: _WriteSimpleXMLElement(outfile, 'meaning', self.help, inner_indent) # The default flag value can either be represented as a string like on the # command line, or as a Python object. We serialize this value in the # latter case in order to remain consistent. if self.serializer and not isinstance(self.default, str): default_serialized = self.serializer.Serialize(self.default) else: default_serialized = self.default _WriteSimpleXMLElement(outfile, 'default', default_serialized, inner_indent) _WriteSimpleXMLElement(outfile, 'current', self.value, inner_indent) _WriteSimpleXMLElement(outfile, 'type', self.Type(), inner_indent) # Print extra flag features this flag may have. self._WriteCustomInfoInXMLFormat(outfile, inner_indent) outfile.write(indent + '</flag>\n') def _WriteCustomInfoInXMLFormat(self, outfile, indent): """Writes extra info about this flag, in XML format. "Extra" means "not already printed by WriteInfoInXMLFormat above." Args: outfile: File object we write to. indent: A string that is prepended to each generated line. """ # Usually, the parser knows the extra details about the flag, so # we just forward the call to it. self.parser.WriteCustomInfoInXMLFormat(outfile, indent) # End of Flag definition class _ArgumentParserCache(type): """Metaclass used to cache and share argument parsers among flags.""" _instances = {} def __call__(mcs, *args, **kwargs): """Returns an instance of the argument parser cls. This method overrides behavior of the __new__ methods in all subclasses of ArgumentParser (inclusive). If an instance for mcs with the same set of arguments exists, this instance is returned, otherwise a new instance is created. If any keyword arguments are defined, or the values in args are not hashable, this method always returns a new instance of cls. Args: args: Positional initializer arguments. kwargs: Initializer keyword arguments. Returns: An instance of cls, shared or new. """ if kwargs: return type.__call__(mcs, *args, **kwargs) else: instances = mcs._instances key = (mcs,) + tuple(args) try: return instances[key] except KeyError: # No cache entry for key exists, create a new one. return instances.setdefault(key, type.__call__(mcs, *args)) except TypeError: # An object in args cannot be hashed, always return # a new instance. return type.__call__(mcs, *args) class ArgumentParser(object): """Base class used to parse and convert arguments. The Parse() method checks to make sure that the string argument is a legal value and convert it to a native type. If the value cannot be converted, it should throw a 'ValueError' exception with a human readable explanation of why the value is illegal. Subclasses should also define a syntactic_help string which may be presented to the user to describe the form of the legal values. Argument parser classes must be stateless, since instances are cached and shared between flags. Initializer arguments are allowed, but all member variables must be derived from initializer arguments only. """ __metaclass__ = _ArgumentParserCache syntactic_help = "" def Parse(self, argument): """Default implementation: always returns its argument unmodified.""" return argument def Type(self): return 'string' def WriteCustomInfoInXMLFormat(self, outfile, indent): pass class ArgumentSerializer: """Base class for generating string representations of a flag value.""" def Serialize(self, value): return str(value) class ListSerializer(ArgumentSerializer): def __init__(self, list_sep): self.list_sep = list_sep def Serialize(self, value): return self.list_sep.join([str(x) for x in value]) # Flags validators def RegisterValidator(flag_name, checker, message='Flag validation failed', flag_values=FLAGS): """Adds a constraint, which will be enforced during program execution. The constraint is validated when flags are initially parsed, and after each change of the corresponding flag's value. Args: flag_name: string, name of the flag to be checked. checker: method to validate the flag. input - value of the corresponding flag (string, boolean, etc. This value will be passed to checker by the library). See file's docstring for examples. output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise gflags_validators.Error(desired_error_message). message: error text to be shown to the user if checker returns False. If checker raises gflags_validators.Error, message from the raised Error will be shown. flag_values: FlagValues Raises: AttributeError: if flag_name is not registered as a valid flag name. """ flag_values.AddValidator(gflags_validators.SimpleValidator(flag_name, checker, message)) def MarkFlagAsRequired(flag_name, flag_values=FLAGS): """Ensure that flag is not None during program execution. Registers a flag validator, which will follow usual validator rules. Args: flag_name: string, name of the flag flag_values: FlagValues Raises: AttributeError: if flag_name is not registered as a valid flag name. """ RegisterValidator(flag_name, lambda value: value is not None, message='Flag --%s must be specified.' % flag_name, flag_values=flag_values) def _RegisterBoundsValidatorIfNeeded(parser, name, flag_values): """Enforce lower and upper bounds for numeric flags. Args: parser: NumericParser (either FloatParser or IntegerParser). Provides lower and upper bounds, and help text to display. name: string, name of the flag flag_values: FlagValues """ if parser.lower_bound is not None or parser.upper_bound is not None: def Checker(value): if value is not None and parser.IsOutsideBounds(value): message = '%s is not %s' % (value, parser.syntactic_help) raise gflags_validators.Error(message) return True RegisterValidator(name, Checker, flag_values=flag_values) # The DEFINE functions are explained in mode details in the module doc string. def DEFINE(parser, name, default, help, flag_values=FLAGS, serializer=None, **args): """Registers a generic Flag object. NOTE: in the docstrings of all DEFINE* functions, "registers" is short for "creates a new flag and registers it". Auxiliary function: clients should use the specialized DEFINE_<type> function instead. Args: parser: ArgumentParser that is used to parse the flag arguments. name: A string, the flag name. default: The default value of the flag. help: A help string. flag_values: FlagValues object the flag will be registered with. serializer: ArgumentSerializer that serializes the flag value. args: Dictionary with extra keyword args that are passes to the Flag __init__. """ DEFINE_flag(Flag(parser, serializer, name, default, help, **args), flag_values) def DEFINE_flag(flag, flag_values=FLAGS): """Registers a 'Flag' object with a 'FlagValues' object. By default, the global FLAGS 'FlagValue' object is used. Typical users will use one of the more specialized DEFINE_xxx functions, such as DEFINE_string or DEFINE_integer. But developers who need to create Flag objects themselves should use this function to register their flags. """ # copying the reference to flag_values prevents pychecker warnings fv = flag_values fv[flag.name] = flag # Tell flag_values who's defining the flag. if isinstance(flag_values, FlagValues): # Regarding the above isinstance test: some users pass funny # values of flag_values (e.g., {}) in order to avoid the flag # registration (in the past, there used to be a flag_values == # FLAGS test here) and redefine flags with the same name (e.g., # debug). To avoid breaking their code, we perform the # registration only if flag_values is a real FlagValues object. flag_values._RegisterFlagByModule(_GetCallingModule(), flag) def _InternalDeclareKeyFlags(flag_names, flag_values=FLAGS, key_flag_values=None): """Declares a flag as key for the calling module. Internal function. User code should call DECLARE_key_flag or ADOPT_module_key_flags instead. Args: flag_names: A list of strings that are names of already-registered Flag objects. flag_values: A FlagValues object that the flags listed in flag_names have registered with (the value of the flag_values argument from the DEFINE_* calls that defined those flags). This should almost never need to be overridden. key_flag_values: A FlagValues object that (among possibly many other things) keeps track of the key flags for each module. Default None means "same as flag_values". This should almost never need to be overridden. Raises: UnrecognizedFlagError: when we refer to a flag that was not defined yet. """ key_flag_values = key_flag_values or flag_values module = _GetCallingModule() for flag_name in flag_names: if flag_name not in flag_values: raise UnrecognizedFlagError(flag_name) flag = flag_values.FlagDict()[flag_name] key_flag_values._RegisterKeyFlagForModule(module, flag) def DECLARE_key_flag(flag_name, flag_values=FLAGS): """Declares one flag as key to the current module. Key flags are flags that are deemed really important for a module. They are important when listing help messages; e.g., if the --helpshort command-line flag is used, then only the key flags of the main module are listed (instead of all flags, as in the case of --help). Sample usage: flags.DECLARED_key_flag('flag_1') Args: flag_name: A string, the name of an already declared flag. (Redeclaring flags as key, including flags implicitly key because they were declared in this module, is a no-op.) flag_values: A FlagValues object. This should almost never need to be overridden. """ if flag_name in _SPECIAL_FLAGS: # Take care of the special flags, e.g., --flagfile, --undefok. # These flags are defined in _SPECIAL_FLAGS, and are treated # specially during flag parsing, taking precedence over the # user-defined flags. _InternalDeclareKeyFlags([flag_name], flag_values=_SPECIAL_FLAGS, key_flag_values=flag_values) return _InternalDeclareKeyFlags([flag_name], flag_values=flag_values) def ADOPT_module_key_flags(module, flag_values=FLAGS): """Declares that all flags key to a module are key to the current module. Args: module: A module object. flag_values: A FlagValues object. This should almost never need to be overridden. Raises: FlagsError: When given an argument that is a module name (a string), instead of a module object. """ # NOTE(salcianu): an even better test would be if not # isinstance(module, types.ModuleType) but I didn't want to import # types for such a tiny use. if isinstance(module, str): raise FlagsError('Received module name %s; expected a module object.' % module) _InternalDeclareKeyFlags( [f.name for f in flag_values._GetKeyFlagsForModule(module.__name__)], flag_values=flag_values) # If module is this flag module, take _SPECIAL_FLAGS into account. if module == _GetThisModuleObjectAndName()[0]: _InternalDeclareKeyFlags( # As we associate flags with _GetCallingModule(), the special # flags defined in this module are incorrectly registered with # a different module. So, we can't use _GetKeyFlagsForModule. # Instead, we take all flags from _SPECIAL_FLAGS (a private # FlagValues, where no other module should register flags). [f.name for f in _SPECIAL_FLAGS.FlagDict().values()], flag_values=_SPECIAL_FLAGS, key_flag_values=flag_values) # # STRING FLAGS # def DEFINE_string(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value can be any string.""" parser = ArgumentParser() serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) # # BOOLEAN FLAGS # # and the special HELP flags. class BooleanParser(ArgumentParser): """Parser of boolean values.""" def Convert(self, argument): """Converts the argument to a boolean; raise ValueError on errors.""" if type(argument) == str: if argument.lower() in ['true', 't', '1']: return True elif argument.lower() in ['false', 'f', '0']: return False bool_argument = bool(argument) if argument == bool_argument: # The argument is a valid boolean (True, False, 0, or 1), and not just # something that always converts to bool (list, string, int, etc.). return bool_argument raise ValueError('Non-boolean argument to boolean flag', argument) def Parse(self, argument): val = self.Convert(argument) return val def Type(self): return 'bool' class BooleanFlag(Flag): """Basic boolean flag. Boolean flags do not take any arguments, and their value is either True (1) or False (0). The false value is specified on the command line by prepending the word 'no' to either the long or the short flag name. For example, if a Boolean flag was created whose long name was 'update' and whose short name was 'x', then this flag could be explicitly unset through either --noupdate or --nox. """ def __init__(self, name, default, help, short_name=None, **args): p = BooleanParser() Flag.__init__(self, p, None, name, default, help, short_name, 1, **args) if not self.help: self.help = "a boolean value" def DEFINE_boolean(name, default, help, flag_values=FLAGS, **args): """Registers a boolean flag. Such a boolean flag does not take an argument. If a user wants to specify a false value explicitly, the long option beginning with 'no' must be used: i.e. --noflag This flag will have a value of None, True or False. None is possible if default=None and the user does not specify the flag on the command line. """ DEFINE_flag(BooleanFlag(name, default, help, **args), flag_values) # Match C++ API to unconfuse C++ people. DEFINE_bool = DEFINE_boolean class HelpFlag(BooleanFlag): """ HelpFlag is a special boolean flag that prints usage information and raises a SystemExit exception if it is ever found in the command line arguments. Note this is called with allow_override=1, so other apps can define their own --help flag, replacing this one, if they want. """ def __init__(self): BooleanFlag.__init__(self, "help", 0, "show this help", short_name="?", allow_override=1) def Parse(self, arg): if arg: doc = sys.modules["__main__"].__doc__ flags = str(FLAGS) print doc or ("\nUSAGE: %s [flags]\n" % sys.argv[0]) if flags: print "flags:" print flags sys.exit(1) class HelpXMLFlag(BooleanFlag): """Similar to HelpFlag, but generates output in XML format.""" def __init__(self): BooleanFlag.__init__(self, 'helpxml', False, 'like --help, but generates XML output', allow_override=1) def Parse(self, arg): if arg: FLAGS.WriteHelpInXMLFormat(sys.stdout) sys.exit(1) class HelpshortFlag(BooleanFlag): """ HelpshortFlag is a special boolean flag that prints usage information for the "main" module, and rasies a SystemExit exception if it is ever found in the command line arguments. Note this is called with allow_override=1, so other apps can define their own --helpshort flag, replacing this one, if they want. """ def __init__(self): BooleanFlag.__init__(self, "helpshort", 0, "show usage only for this module", allow_override=1) def Parse(self, arg): if arg: doc = sys.modules["__main__"].__doc__ flags = FLAGS.MainModuleHelp() print doc or ("\nUSAGE: %s [flags]\n" % sys.argv[0]) if flags: print "flags:" print flags sys.exit(1) # # Numeric parser - base class for Integer and Float parsers # class NumericParser(ArgumentParser): """Parser of numeric values. Parsed value may be bounded to a given upper and lower bound. """ def IsOutsideBounds(self, val): return ((self.lower_bound is not None and val < self.lower_bound) or (self.upper_bound is not None and val > self.upper_bound)) def Parse(self, argument): val = self.Convert(argument) if self.IsOutsideBounds(val): raise ValueError("%s is not %s" % (val, self.syntactic_help)) return val def WriteCustomInfoInXMLFormat(self, outfile, indent): if self.lower_bound is not None: _WriteSimpleXMLElement(outfile, 'lower_bound', self.lower_bound, indent) if self.upper_bound is not None: _WriteSimpleXMLElement(outfile, 'upper_bound', self.upper_bound, indent) def Convert(self, argument): """Default implementation: always returns its argument unmodified.""" return argument # End of Numeric Parser # # FLOAT FLAGS # class FloatParser(NumericParser): """Parser of floating point values. Parsed value may be bounded to a given upper and lower bound. """ number_article = "a" number_name = "number" syntactic_help = " ".join((number_article, number_name)) def __init__(self, lower_bound=None, upper_bound=None): super(FloatParser, self).__init__() self.lower_bound = lower_bound self.upper_bound = upper_bound sh = self.syntactic_help if lower_bound is not None and upper_bound is not None: sh = ("%s in the range [%s, %s]" % (sh, lower_bound, upper_bound)) elif lower_bound == 0: sh = "a non-negative %s" % self.number_name elif upper_bound == 0: sh = "a non-positive %s" % self.number_name elif upper_bound is not None: sh = "%s <= %s" % (self.number_name, upper_bound) elif lower_bound is not None: sh = "%s >= %s" % (self.number_name, lower_bound) self.syntactic_help = sh def Convert(self, argument): """Converts argument to a float; raises ValueError on errors.""" return float(argument) def Type(self): return 'float' # End of FloatParser def DEFINE_float(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value must be a float. If lower_bound or upper_bound are set, then this flag must be within the given range. """ parser = FloatParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) _RegisterBoundsValidatorIfNeeded(parser, name, flag_values=flag_values) # # INTEGER FLAGS # class IntegerParser(NumericParser): """Parser of an integer value. Parsed value may be bounded to a given upper and lower bound. """ number_article = "an" number_name = "integer" syntactic_help = " ".join((number_article, number_name)) def __init__(self, lower_bound=None, upper_bound=None): super(IntegerParser, self).__init__() self.lower_bound = lower_bound self.upper_bound = upper_bound sh = self.syntactic_help if lower_bound is not None and upper_bound is not None: sh = ("%s in the range [%s, %s]" % (sh, lower_bound, upper_bound)) elif lower_bound == 1: sh = "a positive %s" % self.number_name elif upper_bound == -1: sh = "a negative %s" % self.number_name elif lower_bound == 0: sh = "a non-negative %s" % self.number_name elif upper_bound == 0: sh = "a non-positive %s" % self.number_name elif upper_bound is not None: sh = "%s <= %s" % (self.number_name, upper_bound) elif lower_bound is not None: sh = "%s >= %s" % (self.number_name, lower_bound) self.syntactic_help = sh def Convert(self, argument): __pychecker__ = 'no-returnvalues' if type(argument) == str: base = 10 if len(argument) > 2 and argument[0] == "0" and argument[1] == "x": base = 16 try: return int(argument, base) # ValueError is thrown when argument is a string, and overflows an int. except ValueError: return long(argument, base) else: try: return int(argument) # OverflowError is thrown when argument is numeric, and overflows an int. except OverflowError: return long(argument) def Type(self): return 'int' def DEFINE_integer(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value must be an integer. If lower_bound, or upper_bound are set, then this flag must be within the given range. """ parser = IntegerParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) _RegisterBoundsValidatorIfNeeded(parser, name, flag_values=flag_values) # # ENUM FLAGS # class EnumParser(ArgumentParser): """Parser of a string enum value (a string value from a given set). If enum_values (see below) is not specified, any string is allowed. """ def __init__(self, enum_values=None): super(EnumParser, self).__init__() self.enum_values = enum_values def Parse(self, argument): if self.enum_values and argument not in self.enum_values: raise ValueError("value should be one of <%s>" % "|".join(self.enum_values)) return argument def Type(self): return 'string enum' class EnumFlag(Flag): """Basic enum flag; its value can be any string from list of enum_values.""" def __init__(self, name, default, help, enum_values=None, short_name=None, **args): enum_values = enum_values or [] p = EnumParser(enum_values) g = ArgumentSerializer() Flag.__init__(self, p, g, name, default, help, short_name, **args) if not self.help: self.help = "an enum string" self.help = "<%s>: %s" % ("|".join(enum_values), self.help) def _WriteCustomInfoInXMLFormat(self, outfile, indent): for enum_value in self.parser.enum_values: _WriteSimpleXMLElement(outfile, 'enum_value', enum_value, indent) def DEFINE_enum(name, default, enum_values, help, flag_values=FLAGS, **args): """Registers a flag whose value can be any string from enum_values.""" DEFINE_flag(EnumFlag(name, default, help, enum_values, ** args), flag_values) # # LIST FLAGS # class BaseListParser(ArgumentParser): """Base class for a parser of lists of strings. To extend, inherit from this class; from the subclass __init__, call BaseListParser.__init__(self, token, name) where token is a character used to tokenize, and name is a description of the separator. """ def __init__(self, token=None, name=None): assert name super(BaseListParser, self).__init__() self._token = token self._name = name self.syntactic_help = "a %s separated list" % self._name def Parse(self, argument): if isinstance(argument, list): return argument elif argument == '': return [] else: return [s.strip() for s in argument.split(self._token)] def Type(self): return '%s separated list of strings' % self._name class ListParser(BaseListParser): """Parser for a comma-separated list of strings.""" def __init__(self): BaseListParser.__init__(self, ',', 'comma') def WriteCustomInfoInXMLFormat(self, outfile, indent): BaseListParser.WriteCustomInfoInXMLFormat(self, outfile, indent) _WriteSimpleXMLElement(outfile, 'list_separator', repr(','), indent) class WhitespaceSeparatedListParser(BaseListParser): """Parser for a whitespace-separated list of strings.""" def __init__(self): BaseListParser.__init__(self, None, 'whitespace') def WriteCustomInfoInXMLFormat(self, outfile, indent): BaseListParser.WriteCustomInfoInXMLFormat(self, outfile, indent) separators = list(string.whitespace) separators.sort() for ws_char in string.whitespace: _WriteSimpleXMLElement(outfile, 'list_separator', repr(ws_char), indent) def DEFINE_list(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value is a comma-separated list of strings.""" parser = ListParser() serializer = ListSerializer(',') DEFINE(parser, name, default, help, flag_values, serializer, **args) def DEFINE_spaceseplist(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value is a whitespace-separated list of strings. Any whitespace can be used as a separator. """ parser = WhitespaceSeparatedListParser() serializer = ListSerializer(' ') DEFINE(parser, name, default, help, flag_values, serializer, **args) # # MULTI FLAGS # class MultiFlag(Flag): """A flag that can appear multiple time on the command-line. The value of such a flag is a list that contains the individual values from all the appearances of that flag on the command-line. See the __doc__ for Flag for most behavior of this class. Only differences in behavior are described here: * The default value may be either a single value or a list of values. A single value is interpreted as the [value] singleton list. * The value of the flag is always a list, even if the option was only supplied once, and even if the default value is a single value """ def __init__(self, *args, **kwargs): Flag.__init__(self, *args, **kwargs) self.help += ';\n repeat this option to specify a list of values' def Parse(self, arguments): """Parses one or more arguments with the installed parser. Args: arguments: a single argument or a list of arguments (typically a list of default values); a single argument is converted internally into a list containing one item. """ if not isinstance(arguments, list): # Default value may be a list of values. Most other arguments # will not be, so convert them into a single-item list to make # processing simpler below. arguments = [arguments] if self.present: # keep a backup reference to list of previously supplied option values values = self.value else: # "erase" the defaults with an empty list values = [] for item in arguments: # have Flag superclass parse argument, overwriting self.value reference Flag.Parse(self, item) # also increments self.present values.append(self.value) # put list of option values back in the 'value' attribute self.value = values def Serialize(self): if not self.serializer: raise FlagsError("Serializer not present for flag %s" % self.name) if self.value is None: return '' s = '' multi_value = self.value for self.value in multi_value: if s: s += ' ' s += Flag.Serialize(self) self.value = multi_value return s def Type(self): return 'multi ' + self.parser.Type() def DEFINE_multi(parser, serializer, name, default, help, flag_values=FLAGS, **args): """Registers a generic MultiFlag that parses its args with a given parser. Auxiliary function. Normal users should NOT use it directly. Developers who need to create their own 'Parser' classes for options which can appear multiple times can call this module function to register their flags. """ DEFINE_flag(MultiFlag(parser, serializer, name, default, help, **args), flag_values) def DEFINE_multistring(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value can be a list of any strings. Use the flag on the command line multiple times to place multiple string values into the list. The 'default' may be a single string (which will be converted into a single-element list) or a list of strings. """ parser = ArgumentParser() serializer = ArgumentSerializer() DEFINE_multi(parser, serializer, name, default, help, flag_values, **args) def DEFINE_multi_int(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value can be a list of arbitrary integers. Use the flag on the command line multiple times to place multiple integer values into the list. The 'default' may be a single integer (which will be converted into a single-element list) or a list of integers. """ parser = IntegerParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE_multi(parser, serializer, name, default, help, flag_values, **args) # Now register the flags that we want to exist in all applications. # These are all defined with allow_override=1, so user-apps can use # these flagnames for their own purposes, if they want. DEFINE_flag(HelpFlag()) DEFINE_flag(HelpshortFlag()) DEFINE_flag(HelpXMLFlag()) # Define special flags here so that help may be generated for them. # NOTE: Please do NOT use _SPECIAL_FLAGS from outside this module. _SPECIAL_FLAGS = FlagValues() DEFINE_string( 'flagfile', "", "Insert flag definitions from the given file into the command line.", _SPECIAL_FLAGS) DEFINE_string( 'undefok', "", "comma-separated list of flag names that it is okay to specify " "on the command line even if the program does not define a flag " "with that name. IMPORTANT: flags in this list that have " "arguments MUST use the --flag=value format.", _SPECIAL_FLAGS)
Python
#!/usr/bin/env python # Copyright (c) 2010, Google Inc. # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. """Module to enforce different constraints on flags. A validator represents an invariant, enforced over a one or more flags. See 'FLAGS VALIDATORS' in flags.py's docstring for a usage manual. """ __author__ = 'olexiy@google.com (Olexiy Oryeshko)' class Error(Exception): """Thrown If validator constraint is not satisfied.""" class Validator(object): """Base class for flags validators. Users should NOT overload these classes, and use flags.Register... methods instead. """ # Used to assign each validator an unique insertion_index validators_count = 0 def __init__(self, checker, message): """Constructor to create all validators. Args: checker: function to verify the constraint. Input of this method varies, see SimpleValidator and DictionaryValidator for a detailed description. message: string, error message to be shown to the user """ self.checker = checker self.message = message Validator.validators_count += 1 # Used to assert validators in the order they were registered (CL/18694236) self.insertion_index = Validator.validators_count def Verify(self, flag_values): """Verify that constraint is satisfied. flags library calls this method to verify Validator's constraint. Args: flag_values: flags.FlagValues, containing all flags Raises: Error: if constraint is not satisfied. """ param = self._GetInputToCheckerFunction(flag_values) if not self.checker(param): raise Error(self.message) def GetFlagsNames(self): """Return the names of the flags checked by this validator. Returns: [string], names of the flags """ raise NotImplementedError('This method should be overloaded') def PrintFlagsWithValues(self, flag_values): raise NotImplementedError('This method should be overloaded') def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues, containing all flags. Returns: Return type depends on the specific validator. """ raise NotImplementedError('This method should be overloaded') class SimpleValidator(Validator): """Validator behind RegisterValidator() method. Validates that a single flag passes its checker function. The checker function takes the flag value and returns True (if value looks fine) or, if flag value is not valid, either returns False or raises an Exception.""" def __init__(self, flag_name, checker, message): """Constructor. Args: flag_name: string, name of the flag. checker: function to verify the validator. input - value of the corresponding flag (string, boolean, etc). output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise Error. message: string, error message to be shown to the user if validator's condition is not satisfied """ super(SimpleValidator, self).__init__(checker, message) self.flag_name = flag_name def GetFlagsNames(self): return [self.flag_name] def PrintFlagsWithValues(self, flag_values): return 'flag --%s=%s' % (self.flag_name, flag_values[self.flag_name].value) def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues Returns: value of the corresponding flag. """ return flag_values[self.flag_name].value class DictionaryValidator(Validator): """Validator behind RegisterDictionaryValidator method. Validates that flag values pass their common checker function. The checker function takes flag values and returns True (if values look fine) or, if values are not valid, either returns False or raises an Exception. """ def __init__(self, flag_names, checker, message): """Constructor. Args: flag_names: [string], containing names of the flags used by checker. checker: function to verify the validator. input - dictionary, with keys() being flag_names, and value for each key being the value of the corresponding flag (string, boolean, etc). output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise Error. message: string, error message to be shown to the user if validator's condition is not satisfied """ super(DictionaryValidator, self).__init__(checker, message) self.flag_names = flag_names def _GetInputToCheckerFunction(self, flag_values): """Given flag values, construct the input to be given to checker. Args: flag_values: flags.FlagValues Returns: dictionary, with keys() being self.lag_names, and value for each key being the value of the corresponding flag (string, boolean, etc). """ return dict([key, flag_values[key].value] for key in self.flag_names) def PrintFlagsWithValues(self, flag_values): prefix = 'flags ' flags_with_values = [] for key in self.flag_names: flags_with_values.append('%s=%s' % (key, flag_values[key].value)) return prefix + ', '.join(flags_with_values) def GetFlagsNames(self): return self.flag_names
Python
#!/usr/bin/env python # Copyright (c) 2007, Google Inc. # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. # # --- # Author: Chad Lester # Design and style contributions by: # Amit Patel, Bogdan Cocosel, Daniel Dulitz, Eric Tiedemann, # Eric Veach, Laurence Gonsalves, Matthew Springer # Code reorganized a bit by Craig Silverstein """This module is used to define and parse command line flags. This module defines a *distributed* flag-definition policy: rather than an application having to define all flags in or near main(), each python module defines flags that are useful to it. When one python module imports another, it gains access to the other's flags. (This is implemented by having all modules share a common, global registry object containing all the flag information.) Flags are defined through the use of one of the DEFINE_xxx functions. The specific function used determines how the flag is parsed, checked, and optionally type-converted, when it's seen on the command line. IMPLEMENTATION: DEFINE_* creates a 'Flag' object and registers it with a 'FlagValues' object (typically the global FlagValues FLAGS, defined here). The 'FlagValues' object can scan the command line arguments and pass flag arguments to the corresponding 'Flag' objects for value-checking and type conversion. The converted flag values are available as attributes of the 'FlagValues' object. Code can access the flag through a FlagValues object, for instance gflags.FLAGS.myflag. Typically, the __main__ module passes the command line arguments to gflags.FLAGS for parsing. At bottom, this module calls getopt(), so getopt functionality is supported, including short- and long-style flags, and the use of -- to terminate flags. Methods defined by the flag module will throw 'FlagsError' exceptions. The exception argument will be a human-readable string. FLAG TYPES: This is a list of the DEFINE_*'s that you can do. All flags take a name, default value, help-string, and optional 'short' name (one-letter name). Some flags have other arguments, which are described with the flag. DEFINE_string: takes any input, and interprets it as a string. DEFINE_bool or DEFINE_boolean: typically does not take an argument: say --myflag to set FLAGS.myflag to true, or --nomyflag to set FLAGS.myflag to false. Alternately, you can say --myflag=true or --myflag=t or --myflag=1 or --myflag=false or --myflag=f or --myflag=0 DEFINE_float: takes an input and interprets it as a floating point number. Takes optional args lower_bound and upper_bound; if the number specified on the command line is out of range, it will raise a FlagError. DEFINE_integer: takes an input and interprets it as an integer. Takes optional args lower_bound and upper_bound as for floats. DEFINE_enum: takes a list of strings which represents legal values. If the command-line value is not in this list, raise a flag error. Otherwise, assign to FLAGS.flag as a string. DEFINE_list: Takes a comma-separated list of strings on the commandline. Stores them in a python list object. DEFINE_spaceseplist: Takes a space-separated list of strings on the commandline. Stores them in a python list object. Example: --myspacesepflag "foo bar baz" DEFINE_multistring: The same as DEFINE_string, except the flag can be specified more than once on the commandline. The result is a python list object (list of strings), even if the flag is only on the command line once. DEFINE_multi_int: The same as DEFINE_integer, except the flag can be specified more than once on the commandline. The result is a python list object (list of ints), even if the flag is only on the command line once. SPECIAL FLAGS: There are a few flags that have special meaning: --help prints a list of all the flags in a human-readable fashion --helpshort prints a list of all key flags (see below). --helpxml prints a list of all flags, in XML format. DO NOT parse the output of --help and --helpshort. Instead, parse the output of --helpxml. For more info, see "OUTPUT FOR --helpxml" below. --flagfile=foo read flags from file foo. --undefok=f1,f2 ignore unrecognized option errors for f1,f2. For boolean flags, you should use --undefok=boolflag, and --boolflag and --noboolflag will be accepted. Do not use --undefok=noboolflag. -- as in getopt(), terminates flag-processing FLAGS VALIDATORS: If your program: - requires flag X to be specified - needs flag Y to match a regular expression - or requires any more general constraint to be satisfied then validators are for you! Each validator represents a constraint over one flag, which is enforced starting from the initial parsing of the flags and until the program terminates. Also, lower_bound and upper_bound for numerical flags are enforced using flag validators. Howto: If you want to enforce a constraint over one flag, use flags.RegisterValidator(flag_name, checker, message='Flag validation failed', flag_values=FLAGS) After flag values are initially parsed, and after any change to the specified flag, method checker(flag_value) will be executed. If constraint is not satisfied, an IllegalFlagValue exception will be raised. See RegisterValidator's docstring for a detailed explanation on how to construct your own checker. EXAMPLE USAGE: FLAGS = flags.FLAGS flags.DEFINE_integer('my_version', 0, 'Version number.') flags.DEFINE_string('filename', None, 'Input file name', short_name='f') flags.RegisterValidator('my_version', lambda value: value % 2 == 0, message='--my_version must be divisible by 2') flags.MarkFlagAsRequired('filename') NOTE ON --flagfile: Flags may be loaded from text files in addition to being specified on the commandline. Any flags you don't feel like typing, throw them in a file, one flag per line, for instance: --myflag=myvalue --nomyboolean_flag You then specify your file with the special flag '--flagfile=somefile'. You CAN recursively nest flagfile= tokens OR use multiple files on the command line. Lines beginning with a single hash '#' or a double slash '//' are comments in your flagfile. Any flagfile=<file> will be interpreted as having a relative path from the current working directory rather than from the place the file was included from: myPythonScript.py --flagfile=config/somefile.cfg If somefile.cfg includes further --flagfile= directives, these will be referenced relative to the original CWD, not from the directory the including flagfile was found in! The caveat applies to people who are including a series of nested files in a different dir than they are executing out of. Relative path names are always from CWD, not from the directory of the parent include flagfile. We do now support '~' expanded directory names. Absolute path names ALWAYS work! EXAMPLE USAGE: import gflags FLAGS = gflags.FLAGS # Flag names are globally defined! So in general, we need to be # careful to pick names that are unlikely to be used by other libraries. # If there is a conflict, we'll get an error at import time. gflags.DEFINE_string('name', 'Mr. President', 'your name') gflags.DEFINE_integer('age', None, 'your age in years', lower_bound=0) gflags.DEFINE_boolean('debug', False, 'produces debugging output') gflags.DEFINE_enum('gender', 'male', ['male', 'female'], 'your gender') def main(argv): try: argv = FLAGS(argv) # parse flags except gflags.FlagsError, e: print '%s\\nUsage: %s ARGS\\n%s' % (e, sys.argv[0], FLAGS) sys.exit(1) if FLAGS.debug: print 'non-flag arguments:', argv print 'Happy Birthday', FLAGS.name if FLAGS.age is not None: print 'You are a %s, who is %d years old' % (FLAGS.gender, FLAGS.age) if __name__ == '__main__': main(sys.argv) KEY FLAGS: As we already explained, each module gains access to all flags defined by all the other modules it transitively imports. In the case of non-trivial scripts, this means a lot of flags ... For documentation purposes, it is good to identify the flags that are key (i.e., really important) to a module. Clearly, the concept of "key flag" is a subjective one. When trying to determine whether a flag is key to a module or not, assume that you are trying to explain your module to a potential user: which flags would you really like to mention first? We'll describe shortly how to declare which flags are key to a module. For the moment, assume we know the set of key flags for each module. Then, if you use the app.py module, you can use the --helpshort flag to print only the help for the flags that are key to the main module, in a human-readable format. NOTE: If you need to parse the flag help, do NOT use the output of --help / --helpshort. That output is meant for human consumption, and may be changed in the future. Instead, use --helpxml; flags that are key for the main module are marked there with a <key>yes</key> element. The set of key flags for a module M is composed of: 1. Flags defined by module M by calling a DEFINE_* function. 2. Flags that module M explictly declares as key by using the function DECLARE_key_flag(<flag_name>) 3. Key flags of other modules that M specifies by using the function ADOPT_module_key_flags(<other_module>) This is a "bulk" declaration of key flags: each flag that is key for <other_module> becomes key for the current module too. Notice that if you do not use the functions described at points 2 and 3 above, then --helpshort prints information only about the flags defined by the main module of our script. In many cases, this behavior is good enough. But if you move part of the main module code (together with the related flags) into a different module, then it is nice to use DECLARE_key_flag / ADOPT_module_key_flags and make sure --helpshort lists all relevant flags (otherwise, your code refactoring may confuse your users). Note: each of DECLARE_key_flag / ADOPT_module_key_flags has its own pluses and minuses: DECLARE_key_flag is more targeted and may lead a more focused --helpshort documentation. ADOPT_module_key_flags is good for cases when an entire module is considered key to the current script. Also, it does not require updates to client scripts when a new flag is added to the module. EXAMPLE USAGE 2 (WITH KEY FLAGS): Consider an application that contains the following three files (two auxiliary modules and a main module): File libfoo.py: import gflags gflags.DEFINE_integer('num_replicas', 3, 'Number of replicas to start') gflags.DEFINE_boolean('rpc2', True, 'Turn on the usage of RPC2.') ... some code ... File libbar.py: import gflags gflags.DEFINE_string('bar_gfs_path', '/gfs/path', 'Path to the GFS files for libbar.') gflags.DEFINE_string('email_for_bar_errors', 'bar-team@google.com', 'Email address for bug reports about module libbar.') gflags.DEFINE_boolean('bar_risky_hack', False, 'Turn on an experimental and buggy optimization.') ... some code ... File myscript.py: import gflags import libfoo import libbar gflags.DEFINE_integer('num_iterations', 0, 'Number of iterations.') # Declare that all flags that are key for libfoo are # key for this module too. gflags.ADOPT_module_key_flags(libfoo) # Declare that the flag --bar_gfs_path (defined in libbar) is key # for this module. gflags.DECLARE_key_flag('bar_gfs_path') ... some code ... When myscript is invoked with the flag --helpshort, the resulted help message lists information about all the key flags for myscript: --num_iterations, --num_replicas, --rpc2, and --bar_gfs_path (in addition to the special flags --help and --helpshort). Of course, myscript uses all the flags declared by it (in this case, just --num_replicas) or by any of the modules it transitively imports (e.g., the modules libfoo, libbar). E.g., it can access the value of FLAGS.bar_risky_hack, even if --bar_risky_hack is not declared as a key flag for myscript. OUTPUT FOR --helpxml: The --helpxml flag generates output with the following structure: <?xml version="1.0"?> <AllFlags> <program>PROGRAM_BASENAME</program> <usage>MAIN_MODULE_DOCSTRING</usage> (<flag> [<key>yes</key>] <file>DECLARING_MODULE</file> <name>FLAG_NAME</name> <meaning>FLAG_HELP_MESSAGE</meaning> <default>DEFAULT_FLAG_VALUE</default> <current>CURRENT_FLAG_VALUE</current> <type>FLAG_TYPE</type> [OPTIONAL_ELEMENTS] </flag>)* </AllFlags> Notes: 1. The output is intentionally similar to the output generated by the C++ command-line flag library. The few differences are due to the Python flags that do not have a C++ equivalent (at least not yet), e.g., DEFINE_list. 2. New XML elements may be added in the future. 3. DEFAULT_FLAG_VALUE is in serialized form, i.e., the string you can pass for this flag on the command-line. E.g., for a flag defined using DEFINE_list, this field may be foo,bar, not ['foo', 'bar']. 4. CURRENT_FLAG_VALUE is produced using str(). This means that the string 'false' will be represented in the same way as the boolean False. Using repr() would have removed this ambiguity and simplified parsing, but would have broken the compatibility with the C++ command-line flags. 5. OPTIONAL_ELEMENTS describe elements relevant for certain kinds of flags: lower_bound, upper_bound (for flags that specify bounds), enum_value (for enum flags), list_separator (for flags that consist of a list of values, separated by a special token). 6. We do not provide any example here: please use --helpxml instead. """ import cgi import getopt import os import re import string import sys import gflags_validators # Are we running at least python 2.2? try: if tuple(sys.version_info[:3]) < (2,2,0): raise NotImplementedError("requires python 2.2.0 or later") except AttributeError: # a very old python, that lacks sys.version_info raise NotImplementedError("requires python 2.2.0 or later") # If we're not running at least python 2.2.1, define True, False, and bool. # Thanks, Guido, for the code. try: True, False, bool except NameError: False = 0 True = 1 def bool(x): if x: return True else: return False # Are we running under pychecker? _RUNNING_PYCHECKER = 'pychecker.python' in sys.modules def _GetCallingModule(): """Returns the name of the module that's calling into this module. We generally use this function to get the name of the module calling a DEFINE_foo... function. """ # Walk down the stack to find the first globals dict that's not ours. for depth in range(1, sys.getrecursionlimit()): if not sys._getframe(depth).f_globals is globals(): globals_for_frame = sys._getframe(depth).f_globals module_name = _GetModuleObjectAndName(globals_for_frame)[1] if module_name is not None: return module_name raise AssertionError("No module was found") def _GetThisModuleObjectAndName(): """Returns: (module object, module name) for this module.""" return _GetModuleObjectAndName(globals()) # module exceptions: class FlagsError(Exception): """The base class for all flags errors.""" pass class DuplicateFlag(FlagsError): """Raised if there is a flag naming conflict.""" pass class DuplicateFlagCannotPropagateNoneToSwig(DuplicateFlag): """Special case of DuplicateFlag -- SWIG flag value can't be set to None. This can be raised when a duplicate flag is created. Even if allow_override is True, we still abort if the new value is None, because it's currently impossible to pass None default value back to SWIG. See FlagValues.SetDefault for details. """ pass # A DuplicateFlagError conveys more information than a # DuplicateFlag. Since there are external modules that create # DuplicateFlags, the interface to DuplicateFlag shouldn't change. class DuplicateFlagError(DuplicateFlag): def __init__(self, flagname, flag_values): self.flagname = flagname message = "The flag '%s' is defined twice." % self.flagname flags_by_module = flag_values.FlagsByModuleDict() for module in flags_by_module: for flag in flags_by_module[module]: if flag.name == flagname or flag.short_name == flagname: message = message + " First from " + module + "," break message = message + " Second from " + _GetCallingModule() DuplicateFlag.__init__(self, message) class IllegalFlagValue(FlagsError): """The flag command line argument is illegal.""" pass class UnrecognizedFlag(FlagsError): """Raised if a flag is unrecognized.""" pass # An UnrecognizedFlagError conveys more information than an UnrecognizedFlag. # Since there are external modules that create DuplicateFlags, the interface to # DuplicateFlag shouldn't change. The flagvalue will be assigned the full value # of the flag and its argument, if any, allowing handling of unrecognzed flags # in an exception handler. # If flagvalue is the empty string, then this exception is an due to a # reference to a flag that was not already defined. class UnrecognizedFlagError(UnrecognizedFlag): def __init__(self, flagname, flagvalue=''): self.flagname = flagname self.flagvalue = flagvalue UnrecognizedFlag.__init__( self, "Unknown command line flag '%s'" % flagname) # Global variable used by expvar _exported_flags = {} _help_width = 80 # width of help output def GetHelpWidth(): """Returns: an integer, the width of help lines that is used in TextWrap.""" return _help_width def CutCommonSpacePrefix(text): """Removes a common space prefix from the lines of a multiline text. If the first line does not start with a space, it is left as it is and only in the remaining lines a common space prefix is being searched for. That means the first line will stay untouched. This is especially useful to turn doc strings into help texts. This is because some people prefer to have the doc comment start already after the apostrophy and then align the following lines while others have the apostrophies on a seperately line. The function also drops trailing empty lines and ignores empty lines following the initial content line while calculating the initial common whitespace. Args: text: text to work on Returns: the resulting text """ text_lines = text.splitlines() # Drop trailing empty lines while text_lines and not text_lines[-1]: text_lines = text_lines[:-1] if text_lines: # We got some content, is the first line starting with a space? if text_lines[0] and text_lines[0][0].isspace(): text_first_line = [] else: text_first_line = [text_lines.pop(0)] # Calculate length of common leading whitesppace (only over content lines) common_prefix = os.path.commonprefix([line for line in text_lines if line]) space_prefix_len = len(common_prefix) - len(common_prefix.lstrip()) # If we have a common space prefix, drop it from all lines if space_prefix_len: for index in xrange(len(text_lines)): if text_lines[index]: text_lines[index] = text_lines[index][space_prefix_len:] return '\n'.join(text_first_line + text_lines) return '' def TextWrap(text, length=None, indent='', firstline_indent=None, tabs=' '): """Wraps a given text to a maximum line length and returns it. We turn lines that only contain whitespaces into empty lines. We keep new lines and tabs (e.g., we do not treat tabs as spaces). Args: text: text to wrap length: maximum length of a line, includes indentation if this is None then use GetHelpWidth() indent: indent for all but first line firstline_indent: indent for first line; if None, fall back to indent tabs: replacement for tabs Returns: wrapped text Raises: FlagsError: if indent not shorter than length FlagsError: if firstline_indent not shorter than length """ # Get defaults where callee used None if length is None: length = GetHelpWidth() if indent is None: indent = '' if len(indent) >= length: raise FlagsError('Indent must be shorter than length') # In line we will be holding the current line which is to be started # with indent (or firstline_indent if available) and then appended # with words. if firstline_indent is None: firstline_indent = '' line = indent else: line = firstline_indent if len(firstline_indent) >= length: raise FlagsError('First iline indent must be shorter than length') # If the callee does not care about tabs we simply convert them to # spaces If callee wanted tabs to be single space then we do that # already here. if not tabs or tabs == ' ': text = text.replace('\t', ' ') else: tabs_are_whitespace = not tabs.strip() line_regex = re.compile('([ ]*)(\t*)([^ \t]+)', re.MULTILINE) # Split the text into lines and the lines with the regex above. The # resulting lines are collected in result[]. For each split we get the # spaces, the tabs and the next non white space (e.g. next word). result = [] for text_line in text.splitlines(): # Store result length so we can find out whether processing the next # line gave any new content old_result_len = len(result) # Process next line with line_regex. For optimization we do an rstrip(). # - process tabs (changes either line or word, see below) # - process word (first try to squeeze on line, then wrap or force wrap) # Spaces found on the line are ignored, they get added while wrapping as # needed. for spaces, current_tabs, word in line_regex.findall(text_line.rstrip()): # If tabs weren't converted to spaces, handle them now if current_tabs: # If the last thing we added was a space anyway then drop # it. But let's not get rid of the indentation. if (((result and line != indent) or (not result and line != firstline_indent)) and line[-1] == ' '): line = line[:-1] # Add the tabs, if that means adding whitespace, just add it at # the line, the rstrip() code while shorten the line down if # necessary if tabs_are_whitespace: line += tabs * len(current_tabs) else: # if not all tab replacement is whitespace we prepend it to the word word = tabs * len(current_tabs) + word # Handle the case where word cannot be squeezed onto current last line if len(line) + len(word) > length and len(indent) + len(word) <= length: result.append(line.rstrip()) line = indent + word word = '' # No space left on line or can we append a space? if len(line) + 1 >= length: result.append(line.rstrip()) line = indent else: line += ' ' # Add word and shorten it up to allowed line length. Restart next # line with indent and repeat, or add a space if we're done (word # finished) This deals with words that caanot fit on one line # (e.g. indent + word longer than allowed line length). while len(line) + len(word) >= length: line += word result.append(line[:length]) word = line[length:] line = indent # Default case, simply append the word and a space if word: line += word + ' ' # End of input line. If we have content we finish the line. If the # current line is just the indent but we had content in during this # original line then we need to add an emoty line. if (result and line != indent) or (not result and line != firstline_indent): result.append(line.rstrip()) elif len(result) == old_result_len: result.append('') line = indent return '\n'.join(result) def DocToHelp(doc): """Takes a __doc__ string and reformats it as help.""" # Get rid of starting and ending white space. Using lstrip() or even # strip() could drop more than maximum of first line and right space # of last line. doc = doc.strip() # Get rid of all empty lines whitespace_only_line = re.compile('^[ \t]+$', re.M) doc = whitespace_only_line.sub('', doc) # Cut out common space at line beginnings doc = CutCommonSpacePrefix(doc) # Just like this module's comment, comments tend to be aligned somehow. # In other words they all start with the same amount of white space # 1) keep double new lines # 2) keep ws after new lines if not empty line # 3) all other new lines shall be changed to a space # Solution: Match new lines between non white space and replace with space. doc = re.sub('(?<=\S)\n(?=\S)', ' ', doc, re.M) return doc def _GetModuleObjectAndName(globals_dict): """Returns the module that defines a global environment, and its name. Args: globals_dict: A dictionary that should correspond to an environment providing the values of the globals. Returns: A pair consisting of (1) module object and (2) module name (a string). Returns (None, None) if the module could not be identified. """ # The use of .items() (instead of .iteritems()) is NOT a mistake: if # a parallel thread imports a module while we iterate over # .iteritems() (not nice, but possible), we get a RuntimeError ... # Hence, we use the slightly slower but safer .items(). for name, module in sys.modules.items(): if getattr(module, '__dict__', None) is globals_dict: if name == '__main__': # Pick a more informative name for the main module. name = sys.argv[0] return (module, name) return (None, None) def _GetMainModule(): """Returns the name of the module from which execution started.""" for depth in range(1, sys.getrecursionlimit()): try: globals_of_main = sys._getframe(depth).f_globals except ValueError: return _GetModuleObjectAndName(globals_of_main)[1] raise AssertionError("No module was found") class FlagValues: """Registry of 'Flag' objects. A 'FlagValues' can then scan command line arguments, passing flag arguments through to the 'Flag' objects that it owns. It also provides easy access to the flag values. Typically only one 'FlagValues' object is needed by an application: gflags.FLAGS This class is heavily overloaded: 'Flag' objects are registered via __setitem__: FLAGS['longname'] = x # register a new flag The .value attribute of the registered 'Flag' objects can be accessed as attributes of this 'FlagValues' object, through __getattr__. Both the long and short name of the original 'Flag' objects can be used to access its value: FLAGS.longname # parsed flag value FLAGS.x # parsed flag value (short name) Command line arguments are scanned and passed to the registered 'Flag' objects through the __call__ method. Unparsed arguments, including argv[0] (e.g. the program name) are returned. argv = FLAGS(sys.argv) # scan command line arguments The original registered Flag objects can be retrieved through the use of the dictionary-like operator, __getitem__: x = FLAGS['longname'] # access the registered Flag object The str() operator of a 'FlagValues' object provides help for all of the registered 'Flag' objects. """ def __init__(self): # Since everything in this class is so heavily overloaded, the only # way of defining and using fields is to access __dict__ directly. # Dictionary: flag name (string) -> Flag object. self.__dict__['__flags'] = {} # Dictionary: module name (string) -> list of Flag objects that are defined # by that module. self.__dict__['__flags_by_module'] = {} # Dictionary: module name (string) -> list of Flag objects that are # key for that module. self.__dict__['__key_flags_by_module'] = {} # Set if we should use new style gnu_getopt rather than getopt when parsing # the args. Only possible with Python 2.3+ self.UseGnuGetOpt(False) def UseGnuGetOpt(self, use_gnu_getopt=True): self.__dict__['__use_gnu_getopt'] = use_gnu_getopt def IsGnuGetOpt(self): return self.__dict__['__use_gnu_getopt'] def FlagDict(self): return self.__dict__['__flags'] def FlagsByModuleDict(self): """Returns the dictionary of module_name -> list of defined flags. Returns: A dictionary. Its keys are module names (strings). Its values are lists of Flag objects. """ return self.__dict__['__flags_by_module'] def KeyFlagsByModuleDict(self): """Returns the dictionary of module_name -> list of key flags. Returns: A dictionary. Its keys are module names (strings). Its values are lists of Flag objects. """ return self.__dict__['__key_flags_by_module'] def _RegisterFlagByModule(self, module_name, flag): """Records the module that defines a specific flag. We keep track of which flag is defined by which module so that we can later sort the flags by module. Args: module_name: A string, the name of a Python module. flag: A Flag object, a flag that is key to the module. """ flags_by_module = self.FlagsByModuleDict() flags_by_module.setdefault(module_name, []).append(flag) def _RegisterKeyFlagForModule(self, module_name, flag): """Specifies that a flag is a key flag for a module. Args: module_name: A string, the name of a Python module. flag: A Flag object, a flag that is key to the module. """ key_flags_by_module = self.KeyFlagsByModuleDict() # The list of key flags for the module named module_name. key_flags = key_flags_by_module.setdefault(module_name, []) # Add flag, but avoid duplicates. if flag not in key_flags: key_flags.append(flag) def _GetFlagsDefinedByModule(self, module): """Returns the list of flags defined by a module. Args: module: A module object or a module name (a string). Returns: A new list of Flag objects. Caller may update this list as he wishes: none of those changes will affect the internals of this FlagValue object. """ if not isinstance(module, str): module = module.__name__ return list(self.FlagsByModuleDict().get(module, [])) def _GetKeyFlagsForModule(self, module): """Returns the list of key flags for a module. Args: module: A module object or a module name (a string) Returns: A new list of Flag objects. Caller may update this list as he wishes: none of those changes will affect the internals of this FlagValue object. """ if not isinstance(module, str): module = module.__name__ # Any flag is a key flag for the module that defined it. NOTE: # key_flags is a fresh list: we can update it without affecting the # internals of this FlagValues object. key_flags = self._GetFlagsDefinedByModule(module) # Take into account flags explicitly declared as key for a module. for flag in self.KeyFlagsByModuleDict().get(module, []): if flag not in key_flags: key_flags.append(flag) return key_flags def AppendFlagValues(self, flag_values): """Appends flags registered in another FlagValues instance. Args: flag_values: registry to copy from """ for flag_name, flag in flag_values.FlagDict().iteritems(): # Each flags with shortname appears here twice (once under its # normal name, and again with its short name). To prevent # problems (DuplicateFlagError) with double flag registration, we # perform a check to make sure that the entry we're looking at is # for its normal name. if flag_name == flag.name: self[flag_name] = flag def RemoveFlagValues(self, flag_values): """Remove flags that were previously appended from another FlagValues. Args: flag_values: registry containing flags to remove. """ for flag_name in flag_values.FlagDict(): self.__delattr__(flag_name) def __setitem__(self, name, flag): """Registers a new flag variable.""" fl = self.FlagDict() if not isinstance(flag, Flag): raise IllegalFlagValue(flag) if not isinstance(name, type("")): raise FlagsError("Flag name must be a string") if len(name) == 0: raise FlagsError("Flag name cannot be empty") # If running under pychecker, duplicate keys are likely to be # defined. Disable check for duplicate keys when pycheck'ing. if (fl.has_key(name) and not flag.allow_override and not fl[name].allow_override and not _RUNNING_PYCHECKER): raise DuplicateFlagError(name, self) short_name = flag.short_name if short_name is not None: if (fl.has_key(short_name) and not flag.allow_override and not fl[short_name].allow_override and not _RUNNING_PYCHECKER): raise DuplicateFlagError(short_name, self) fl[short_name] = flag fl[name] = flag global _exported_flags _exported_flags[name] = flag def __getitem__(self, name): """Retrieves the Flag object for the flag --name.""" return self.FlagDict()[name] def __getattr__(self, name): """Retrieves the 'value' attribute of the flag --name.""" fl = self.FlagDict() if not fl.has_key(name): raise AttributeError(name) return fl[name].value def __setattr__(self, name, value): """Sets the 'value' attribute of the flag --name.""" fl = self.FlagDict() fl[name].value = value self._AssertValidators(fl[name].validators) return value def _AssertAllValidators(self): all_validators = set() for flag in self.FlagDict().itervalues(): for validator in flag.validators: all_validators.add(validator) self._AssertValidators(all_validators) def _AssertValidators(self, validators): """Assert if all validators in the list are satisfied. Asserts validators in the order they were created. Args: validators: Iterable(gflags_validators.Validator), validators to be verified Raises: AttributeError: if validators work with a non-existing flag. IllegalFlagValue: if validation fails for at least one validator """ for validator in sorted( validators, key=lambda validator: validator.insertion_index): try: validator.Verify(self) except gflags_validators.Error, e: message = validator.PrintFlagsWithValues(self) raise IllegalFlagValue('%s: %s' % (message, str(e))) def _FlagIsRegistered(self, flag_obj): """Checks whether a Flag object is registered under some name. Note: this is non trivial: in addition to its normal name, a flag may have a short name too. In self.FlagDict(), both the normal and the short name are mapped to the same flag object. E.g., calling only "del FLAGS.short_name" is not unregistering the corresponding Flag object (it is still registered under the longer name). Args: flag_obj: A Flag object. Returns: A boolean: True iff flag_obj is registered under some name. """ flag_dict = self.FlagDict() # Check whether flag_obj is registered under its long name. name = flag_obj.name if flag_dict.get(name, None) == flag_obj: return True # Check whether flag_obj is registered under its short name. short_name = flag_obj.short_name if (short_name is not None and flag_dict.get(short_name, None) == flag_obj): return True # The flag cannot be registered under any other name, so we do not # need to do a full search through the values of self.FlagDict(). return False def __delattr__(self, flag_name): """Deletes a previously-defined flag from a flag object. This method makes sure we can delete a flag by using del flag_values_object.<flag_name> E.g., flags.DEFINE_integer('foo', 1, 'Integer flag.') del flags.FLAGS.foo Args: flag_name: A string, the name of the flag to be deleted. Raises: AttributeError: When there is no registered flag named flag_name. """ fl = self.FlagDict() if flag_name not in fl: raise AttributeError(flag_name) flag_obj = fl[flag_name] del fl[flag_name] if not self._FlagIsRegistered(flag_obj): # If the Flag object indicated by flag_name is no longer # registered (please see the docstring of _FlagIsRegistered), then # we delete the occurences of the flag object in all our internal # dictionaries. self.__RemoveFlagFromDictByModule(self.FlagsByModuleDict(), flag_obj) self.__RemoveFlagFromDictByModule(self.KeyFlagsByModuleDict(), flag_obj) def __RemoveFlagFromDictByModule(self, flags_by_module_dict, flag_obj): """Removes a flag object from a module -> list of flags dictionary. Args: flags_by_module_dict: A dictionary that maps module names to lists of flags. flag_obj: A flag object. """ for unused_module, flags_in_module in flags_by_module_dict.iteritems(): # while (as opposed to if) takes care of multiple occurences of a # flag in the list for the same module. while flag_obj in flags_in_module: flags_in_module.remove(flag_obj) def SetDefault(self, name, value): """Changes the default value of the named flag object.""" fl = self.FlagDict() if not fl.has_key(name): raise AttributeError(name) fl[name].SetDefault(value) self._AssertValidators(fl[name].validators) def __contains__(self, name): """Returns True if name is a value (flag) in the dict.""" return name in self.FlagDict() has_key = __contains__ # a synonym for __contains__() def __iter__(self): return self.FlagDict().iterkeys() def __call__(self, argv): """Parses flags from argv; stores parsed flags into this FlagValues object. All unparsed arguments are returned. Flags are parsed using the GNU Program Argument Syntax Conventions, using getopt: http://www.gnu.org/software/libc/manual/html_mono/libc.html#Getopt Args: argv: argument list. Can be of any type that may be converted to a list. Returns: The list of arguments not parsed as options, including argv[0] Raises: FlagsError: on any parsing error """ # Support any sequence type that can be converted to a list argv = list(argv) shortopts = "" longopts = [] fl = self.FlagDict() # This pre parses the argv list for --flagfile=<> options. argv = argv[:1] + self.ReadFlagsFromFiles(argv[1:], force_gnu=False) # Correct the argv to support the google style of passing boolean # parameters. Boolean parameters may be passed by using --mybool, # --nomybool, --mybool=(true|false|1|0). getopt does not support # having options that may or may not have a parameter. We replace # instances of the short form --mybool and --nomybool with their # full forms: --mybool=(true|false). original_argv = list(argv) # list() makes a copy shortest_matches = None for name, flag in fl.items(): if not flag.boolean: continue if shortest_matches is None: # Determine the smallest allowable prefix for all flag names shortest_matches = self.ShortestUniquePrefixes(fl) no_name = 'no' + name prefix = shortest_matches[name] no_prefix = shortest_matches[no_name] # Replace all occurences of this boolean with extended forms for arg_idx in range(1, len(argv)): arg = argv[arg_idx] if arg.find('=') >= 0: continue if arg.startswith('--'+prefix) and ('--'+name).startswith(arg): argv[arg_idx] = ('--%s=true' % name) elif arg.startswith('--'+no_prefix) and ('--'+no_name).startswith(arg): argv[arg_idx] = ('--%s=false' % name) # Loop over all of the flags, building up the lists of short options # and long options that will be passed to getopt. Short options are # specified as a string of letters, each letter followed by a colon # if it takes an argument. Long options are stored in an array of # strings. Each string ends with an '=' if it takes an argument. for name, flag in fl.items(): longopts.append(name + "=") if len(name) == 1: # one-letter option: allow short flag type also shortopts += name if not flag.boolean: shortopts += ":" longopts.append('undefok=') undefok_flags = [] # In case --undefok is specified, loop to pick up unrecognized # options one by one. unrecognized_opts = [] args = argv[1:] while True: try: if self.__dict__['__use_gnu_getopt']: optlist, unparsed_args = getopt.gnu_getopt(args, shortopts, longopts) else: optlist, unparsed_args = getopt.getopt(args, shortopts, longopts) break except getopt.GetoptError, e: if not e.opt or e.opt in fl: # Not an unrecognized option, reraise the exception as a FlagsError raise FlagsError(e) # Remove offender from args and try again for arg_index in range(len(args)): if ((args[arg_index] == '--' + e.opt) or (args[arg_index] == '-' + e.opt) or (args[arg_index].startswith('--' + e.opt + '='))): unrecognized_opts.append((e.opt, args[arg_index])) args = args[0:arg_index] + args[arg_index+1:] break else: # We should have found the option, so we don't expect to get # here. We could assert, but raising the original exception # might work better. raise FlagsError(e) for name, arg in optlist: if name == '--undefok': flag_names = arg.split(',') undefok_flags.extend(flag_names) # For boolean flags, if --undefok=boolflag is specified, then we should # also accept --noboolflag, in addition to --boolflag. # Since we don't know the type of the undefok'd flag, this will affect # non-boolean flags as well. # NOTE: You shouldn't use --undefok=noboolflag, because then we will # accept --nonoboolflag here. We are choosing not to do the conversion # from noboolflag -> boolflag because of the ambiguity that flag names # can start with 'no'. undefok_flags.extend('no' + name for name in flag_names) continue if name.startswith('--'): # long option name = name[2:] short_option = 0 else: # short option name = name[1:] short_option = 1 if fl.has_key(name): flag = fl[name] if flag.boolean and short_option: arg = 1 flag.Parse(arg) # If there were unrecognized options, raise an exception unless # the options were named via --undefok. for opt, value in unrecognized_opts: if opt not in undefok_flags: raise UnrecognizedFlagError(opt, value) if unparsed_args: if self.__dict__['__use_gnu_getopt']: # if using gnu_getopt just return the program name + remainder of argv. ret_val = argv[:1] + unparsed_args else: # unparsed_args becomes the first non-flag detected by getopt to # the end of argv. Because argv may have been modified above, # return original_argv for this region. ret_val = argv[:1] + original_argv[-len(unparsed_args):] else: ret_val = argv[:1] self._AssertAllValidators() return ret_val def Reset(self): """Resets the values to the point before FLAGS(argv) was called.""" for f in self.FlagDict().values(): f.Unparse() def RegisteredFlags(self): """Returns: a list of the names and short names of all registered flags.""" return self.FlagDict().keys() def FlagValuesDict(self): """Returns: a dictionary that maps flag names to flag values.""" flag_values = {} for flag_name in self.RegisteredFlags(): flag = self.FlagDict()[flag_name] flag_values[flag_name] = flag.value return flag_values def __str__(self): """Generates a help string for all known flags.""" return self.GetHelp() def GetHelp(self, prefix=''): """Generates a help string for all known flags.""" helplist = [] flags_by_module = self.FlagsByModuleDict() if flags_by_module: modules = flags_by_module.keys() modules.sort() # Print the help for the main module first, if possible. main_module = _GetMainModule() if main_module in modules: modules.remove(main_module) modules = [main_module] + modules for module in modules: self.__RenderOurModuleFlags(module, helplist) self.__RenderModuleFlags('gflags', _SPECIAL_FLAGS.FlagDict().values(), helplist) else: # Just print one long list of flags. self.__RenderFlagList( self.FlagDict().values() + _SPECIAL_FLAGS.FlagDict().values(), helplist, prefix) return '\n'.join(helplist) def __RenderModuleFlags(self, module, flags, output_lines, prefix=""): """Generates a help string for a given module.""" if not isinstance(module, str): module = module.__name__ output_lines.append('\n%s%s:' % (prefix, module)) self.__RenderFlagList(flags, output_lines, prefix + " ") def __RenderOurModuleFlags(self, module, output_lines, prefix=""): """Generates a help string for a given module.""" flags = self._GetFlagsDefinedByModule(module) if flags: self.__RenderModuleFlags(module, flags, output_lines, prefix) def __RenderOurModuleKeyFlags(self, module, output_lines, prefix=""): """Generates a help string for the key flags of a given module. Args: module: A module object or a module name (a string). output_lines: A list of strings. The generated help message lines will be appended to this list. prefix: A string that is prepended to each generated help line. """ key_flags = self._GetKeyFlagsForModule(module) if key_flags: self.__RenderModuleFlags(module, key_flags, output_lines, prefix) def ModuleHelp(self, module): """Describe the key flags of a module. Args: module: A module object or a module name (a string). Returns: string describing the key flags of a module. """ helplist = [] self.__RenderOurModuleKeyFlags(module, helplist) return '\n'.join(helplist) def MainModuleHelp(self): """Describe the key flags of the main module. Returns: string describing the key flags of a module. """ return self.ModuleHelp(_GetMainModule()) def __RenderFlagList(self, flaglist, output_lines, prefix=" "): fl = self.FlagDict() special_fl = _SPECIAL_FLAGS.FlagDict() flaglist = [(flag.name, flag) for flag in flaglist] flaglist.sort() flagset = {} for (name, flag) in flaglist: # It's possible this flag got deleted or overridden since being # registered in the per-module flaglist. Check now against the # canonical source of current flag information, the FlagDict. if fl.get(name, None) != flag and special_fl.get(name, None) != flag: # a different flag is using this name now continue # only print help once if flagset.has_key(flag): continue flagset[flag] = 1 flaghelp = "" if flag.short_name: flaghelp += "-%s," % flag.short_name if flag.boolean: flaghelp += "--[no]%s" % flag.name + ":" else: flaghelp += "--%s" % flag.name + ":" flaghelp += " " if flag.help: flaghelp += flag.help flaghelp = TextWrap(flaghelp, indent=prefix+" ", firstline_indent=prefix) if flag.default_as_str: flaghelp += "\n" flaghelp += TextWrap("(default: %s)" % flag.default_as_str, indent=prefix+" ") if flag.parser.syntactic_help: flaghelp += "\n" flaghelp += TextWrap("(%s)" % flag.parser.syntactic_help, indent=prefix+" ") output_lines.append(flaghelp) def get(self, name, default): """Returns the value of a flag (if not None) or a default value. Args: name: A string, the name of a flag. default: Default value to use if the flag value is None. """ value = self.__getattr__(name) if value is not None: # Can't do if not value, b/c value might be '0' or "" return value else: return default def ShortestUniquePrefixes(self, fl): """Returns: dictionary; maps flag names to their shortest unique prefix.""" # Sort the list of flag names sorted_flags = [] for name, flag in fl.items(): sorted_flags.append(name) if flag.boolean: sorted_flags.append('no%s' % name) sorted_flags.sort() # For each name in the sorted list, determine the shortest unique # prefix by comparing itself to the next name and to the previous # name (the latter check uses cached info from the previous loop). shortest_matches = {} prev_idx = 0 for flag_idx in range(len(sorted_flags)): curr = sorted_flags[flag_idx] if flag_idx == (len(sorted_flags) - 1): next = None else: next = sorted_flags[flag_idx+1] next_len = len(next) for curr_idx in range(len(curr)): if (next is None or curr_idx >= next_len or curr[curr_idx] != next[curr_idx]): # curr longer than next or no more chars in common shortest_matches[curr] = curr[:max(prev_idx, curr_idx) + 1] prev_idx = curr_idx break else: # curr shorter than (or equal to) next shortest_matches[curr] = curr prev_idx = curr_idx + 1 # next will need at least one more char return shortest_matches def __IsFlagFileDirective(self, flag_string): """Checks whether flag_string contain a --flagfile=<foo> directive.""" if isinstance(flag_string, type("")): if flag_string.startswith('--flagfile='): return 1 elif flag_string == '--flagfile': return 1 elif flag_string.startswith('-flagfile='): return 1 elif flag_string == '-flagfile': return 1 else: return 0 return 0 def ExtractFilename(self, flagfile_str): """Returns filename from a flagfile_str of form -[-]flagfile=filename. The cases of --flagfile foo and -flagfile foo shouldn't be hitting this function, as they are dealt with in the level above this function. """ if flagfile_str.startswith('--flagfile='): return os.path.expanduser((flagfile_str[(len('--flagfile=')):]).strip()) elif flagfile_str.startswith('-flagfile='): return os.path.expanduser((flagfile_str[(len('-flagfile=')):]).strip()) else: raise FlagsError('Hit illegal --flagfile type: %s' % flagfile_str) def __GetFlagFileLines(self, filename, parsed_file_list): """Returns the useful (!=comments, etc) lines from a file with flags. Args: filename: A string, the name of the flag file. parsed_file_list: A list of the names of the files we have already read. MUTATED BY THIS FUNCTION. Returns: List of strings. See the note below. NOTE(springer): This function checks for a nested --flagfile=<foo> tag and handles the lower file recursively. It returns a list of all the lines that _could_ contain command flags. This is EVERYTHING except whitespace lines and comments (lines starting with '#' or '//'). """ line_list = [] # All line from flagfile. flag_line_list = [] # Subset of lines w/o comments, blanks, flagfile= tags. try: file_obj = open(filename, 'r') except IOError, e_msg: print e_msg print 'ERROR:: Unable to open flagfile: %s' % (filename) return flag_line_list line_list = file_obj.readlines() file_obj.close() parsed_file_list.append(filename) # This is where we check each line in the file we just read. for line in line_list: if line.isspace(): pass # Checks for comment (a line that starts with '#'). elif line.startswith('#') or line.startswith('//'): pass # Checks for a nested "--flagfile=<bar>" flag in the current file. # If we find one, recursively parse down into that file. elif self.__IsFlagFileDirective(line): sub_filename = self.ExtractFilename(line) # We do a little safety check for reparsing a file we've already done. if not sub_filename in parsed_file_list: included_flags = self.__GetFlagFileLines(sub_filename, parsed_file_list) flag_line_list.extend(included_flags) else: # Case of hitting a circularly included file. print >>sys.stderr, ('Warning: Hit circular flagfile dependency: %s' % sub_filename) else: # Any line that's not a comment or a nested flagfile should get # copied into 2nd position. This leaves earlier arguements # further back in the list, thus giving them higher priority. flag_line_list.append(line.strip()) return flag_line_list def ReadFlagsFromFiles(self, argv, force_gnu=True): """Processes command line args, but also allow args to be read from file. Args: argv: A list of strings, usually sys.argv[1:], which may contain one or more flagfile directives of the form --flagfile="./filename". Note that the name of the program (sys.argv[0]) should be omitted. force_gnu: If False, --flagfile parsing obeys normal flag semantics. If True, --flagfile parsing instead follows gnu_getopt semantics. *** WARNING *** force_gnu=False may become the future default! Returns: A new list which has the original list combined with what we read from any flagfile(s). References: Global gflags.FLAG class instance. This function should be called before the normal FLAGS(argv) call. This function scans the input list for a flag that looks like: --flagfile=<somefile>. Then it opens <somefile>, reads all valid key and value pairs and inserts them into the input list between the first item of the list and any subsequent items in the list. Note that your application's flags are still defined the usual way using gflags DEFINE_flag() type functions. Notes (assuming we're getting a commandline of some sort as our input): --> Flags from the command line argv _should_ always take precedence! --> A further "--flagfile=<otherfile.cfg>" CAN be nested in a flagfile. It will be processed after the parent flag file is done. --> For duplicate flags, first one we hit should "win". --> In a flagfile, a line beginning with # or // is a comment. --> Entirely blank lines _should_ be ignored. """ parsed_file_list = [] rest_of_args = argv new_argv = [] while rest_of_args: current_arg = rest_of_args[0] rest_of_args = rest_of_args[1:] if self.__IsFlagFileDirective(current_arg): # This handles the case of -(-)flagfile foo. In this case the # next arg really is part of this one. if current_arg == '--flagfile' or current_arg == '-flagfile': if not rest_of_args: raise IllegalFlagValue('--flagfile with no argument') flag_filename = os.path.expanduser(rest_of_args[0]) rest_of_args = rest_of_args[1:] else: # This handles the case of (-)-flagfile=foo. flag_filename = self.ExtractFilename(current_arg) new_argv[0:0] = self.__GetFlagFileLines(flag_filename, parsed_file_list) else: new_argv.append(current_arg) # Stop parsing after '--', like getopt and gnu_getopt. if current_arg == '--': break # Stop parsing after a non-flag, like getopt. if not current_arg.startswith('-'): if not force_gnu and not self.__dict__['__use_gnu_getopt']: break if rest_of_args: new_argv.extend(rest_of_args) return new_argv def FlagsIntoString(self): """Returns a string with the flags assignments from this FlagValues object. This function ignores flags whose value is None. Each flag assignment is separated by a newline. NOTE: MUST mirror the behavior of the C++ function CommandlineFlagsIntoString from google3/base/commandlineflags.cc. """ s = '' for flag in self.FlagDict().values(): if flag.value is not None: s += flag.Serialize() + '\n' return s def AppendFlagsIntoFile(self, filename): """Appends all flags assignments from this FlagInfo object to a file. Output will be in the format of a flagfile. NOTE: MUST mirror the behavior of the C++ version of AppendFlagsIntoFile from google3/base/commandlineflags.cc. """ out_file = open(filename, 'a') out_file.write(self.FlagsIntoString()) out_file.close() def WriteHelpInXMLFormat(self, outfile=None): """Outputs flag documentation in XML format. NOTE: We use element names that are consistent with those used by the C++ command-line flag library, from google3/base/commandlineflags_reporting.cc. We also use a few new elements (e.g., <key>), but we do not interfere / overlap with existing XML elements used by the C++ library. Please maintain this consistency. Args: outfile: File object we write to. Default None means sys.stdout. """ outfile = outfile or sys.stdout outfile.write('<?xml version=\"1.0\"?>\n') outfile.write('<AllFlags>\n') indent = ' ' _WriteSimpleXMLElement(outfile, 'program', os.path.basename(sys.argv[0]), indent) usage_doc = sys.modules['__main__'].__doc__ if not usage_doc: usage_doc = '\nUSAGE: %s [flags]\n' % sys.argv[0] else: usage_doc = usage_doc.replace('%s', sys.argv[0]) _WriteSimpleXMLElement(outfile, 'usage', usage_doc, indent) # Get list of key flags for the main module. key_flags = self._GetKeyFlagsForModule(_GetMainModule()) # Sort flags by declaring module name and next by flag name. flags_by_module = self.FlagsByModuleDict() all_module_names = list(flags_by_module.keys()) all_module_names.sort() for module_name in all_module_names: flag_list = [(f.name, f) for f in flags_by_module[module_name]] flag_list.sort() for unused_flag_name, flag in flag_list: is_key = flag in key_flags flag.WriteInfoInXMLFormat(outfile, module_name, is_key=is_key, indent=indent) outfile.write('</AllFlags>\n') outfile.flush() def AddValidator(self, validator): """Register new flags validator to be checked. Args: validator: gflags_validators.Validator Raises: AttributeError: if validators work with a non-existing flag. """ for flag_name in validator.GetFlagsNames(): flag = self.FlagDict()[flag_name] flag.validators.append(validator) # end of FlagValues definition # The global FlagValues instance FLAGS = FlagValues() def _MakeXMLSafe(s): """Escapes <, >, and & from s, and removes XML 1.0-illegal chars.""" s = cgi.escape(s) # Escape <, >, and & # Remove characters that cannot appear in an XML 1.0 document # (http://www.w3.org/TR/REC-xml/#charsets). # # NOTE: if there are problems with current solution, one may move to # XML 1.1, which allows such chars, if they're entity-escaped (&#xHH;). s = re.sub(r'[\x00-\x08\x0b\x0c\x0e-\x1f]', '', s) return s def _WriteSimpleXMLElement(outfile, name, value, indent): """Writes a simple XML element. Args: outfile: File object we write the XML element to. name: A string, the name of XML element. value: A Python object, whose string representation will be used as the value of the XML element. indent: A string, prepended to each line of generated output. """ value_str = str(value) if isinstance(value, bool): # Display boolean values as the C++ flag library does: no caps. value_str = value_str.lower() outfile.write('%s<%s>%s</%s>\n' % (indent, name, _MakeXMLSafe(value_str), name)) class Flag: """Information about a command-line flag. 'Flag' objects define the following fields: .name - the name for this flag .default - the default value for this flag .default_as_str - default value as repr'd string, e.g., "'true'" (or None) .value - the most recent parsed value of this flag; set by Parse() .help - a help string or None if no help is available .short_name - the single letter alias for this flag (or None) .boolean - if 'true', this flag does not accept arguments .present - true if this flag was parsed from command line flags. .parser - an ArgumentParser object .serializer - an ArgumentSerializer object .allow_override - the flag may be redefined without raising an error The only public method of a 'Flag' object is Parse(), but it is typically only called by a 'FlagValues' object. The Parse() method is a thin wrapper around the 'ArgumentParser' Parse() method. The parsed value is saved in .value, and the .present attribute is updated. If this flag was already present, a FlagsError is raised. Parse() is also called during __init__ to parse the default value and initialize the .value attribute. This enables other python modules to safely use flags even if the __main__ module neglects to parse the command line arguments. The .present attribute is cleared after __init__ parsing. If the default value is set to None, then the __init__ parsing step is skipped and the .value attribute is initialized to None. Note: The default value is also presented to the user in the help string, so it is important that it be a legal value for this flag. """ def __init__(self, parser, serializer, name, default, help_string, short_name=None, boolean=0, allow_override=0): self.name = name if not help_string: help_string = '(no help available)' self.help = help_string self.short_name = short_name self.boolean = boolean self.present = 0 self.parser = parser self.serializer = serializer self.allow_override = allow_override self.value = None self.validators = [] self.SetDefault(default) def __GetParsedValueAsString(self, value): if value is None: return None if self.serializer: return repr(self.serializer.Serialize(value)) if self.boolean: if value: return repr('true') else: return repr('false') return repr(str(value)) def Parse(self, argument): try: self.value = self.parser.Parse(argument) except ValueError, e: # recast ValueError as IllegalFlagValue raise IllegalFlagValue("flag --%s=%s: %s" % (self.name, argument, e)) self.present += 1 def Unparse(self): if self.default is None: self.value = None else: self.Parse(self.default) self.present = 0 def Serialize(self): if self.value is None: return '' if self.boolean: if self.value: return "--%s" % self.name else: return "--no%s" % self.name else: if not self.serializer: raise FlagsError("Serializer not present for flag %s" % self.name) return "--%s=%s" % (self.name, self.serializer.Serialize(self.value)) def SetDefault(self, value): """Changes the default value (and current value too) for this Flag.""" # We can't allow a None override because it may end up not being # passed to C++ code when we're overriding C++ flags. So we # cowardly bail out until someone fixes the semantics of trying to # pass None to a C++ flag. See swig_flags.Init() for details on # this behavior. # TODO(olexiy): Users can directly call this method, bypassing all flags # validators (we don't have FlagValues here, so we can not check # validators). # The simplest solution I see is to make this method private. # Another approach would be to store reference to the corresponding # FlagValues with each flag, but this seems to be an overkill. if value is None and self.allow_override: raise DuplicateFlagCannotPropagateNoneToSwig(self.name) self.default = value self.Unparse() self.default_as_str = self.__GetParsedValueAsString(self.value) def Type(self): """Returns: a string that describes the type of this Flag.""" # NOTE: we use strings, and not the types.*Type constants because # our flags can have more exotic types, e.g., 'comma separated list # of strings', 'whitespace separated list of strings', etc. return self.parser.Type() def WriteInfoInXMLFormat(self, outfile, module_name, is_key=False, indent=''): """Writes common info about this flag, in XML format. This is information that is relevant to all flags (e.g., name, meaning, etc.). If you defined a flag that has some other pieces of info, then please override _WriteCustomInfoInXMLFormat. Please do NOT override this method. Args: outfile: File object we write to. module_name: A string, the name of the module that defines this flag. is_key: A boolean, True iff this flag is key for main module. indent: A string that is prepended to each generated line. """ outfile.write(indent + '<flag>\n') inner_indent = indent + ' ' if is_key: _WriteSimpleXMLElement(outfile, 'key', 'yes', inner_indent) _WriteSimpleXMLElement(outfile, 'file', module_name, inner_indent) # Print flag features that are relevant for all flags. _WriteSimpleXMLElement(outfile, 'name', self.name, inner_indent) if self.short_name: _WriteSimpleXMLElement(outfile, 'short_name', self.short_name, inner_indent) if self.help: _WriteSimpleXMLElement(outfile, 'meaning', self.help, inner_indent) # The default flag value can either be represented as a string like on the # command line, or as a Python object. We serialize this value in the # latter case in order to remain consistent. if self.serializer and not isinstance(self.default, str): default_serialized = self.serializer.Serialize(self.default) else: default_serialized = self.default _WriteSimpleXMLElement(outfile, 'default', default_serialized, inner_indent) _WriteSimpleXMLElement(outfile, 'current', self.value, inner_indent) _WriteSimpleXMLElement(outfile, 'type', self.Type(), inner_indent) # Print extra flag features this flag may have. self._WriteCustomInfoInXMLFormat(outfile, inner_indent) outfile.write(indent + '</flag>\n') def _WriteCustomInfoInXMLFormat(self, outfile, indent): """Writes extra info about this flag, in XML format. "Extra" means "not already printed by WriteInfoInXMLFormat above." Args: outfile: File object we write to. indent: A string that is prepended to each generated line. """ # Usually, the parser knows the extra details about the flag, so # we just forward the call to it. self.parser.WriteCustomInfoInXMLFormat(outfile, indent) # End of Flag definition class _ArgumentParserCache(type): """Metaclass used to cache and share argument parsers among flags.""" _instances = {} def __call__(mcs, *args, **kwargs): """Returns an instance of the argument parser cls. This method overrides behavior of the __new__ methods in all subclasses of ArgumentParser (inclusive). If an instance for mcs with the same set of arguments exists, this instance is returned, otherwise a new instance is created. If any keyword arguments are defined, or the values in args are not hashable, this method always returns a new instance of cls. Args: args: Positional initializer arguments. kwargs: Initializer keyword arguments. Returns: An instance of cls, shared or new. """ if kwargs: return type.__call__(mcs, *args, **kwargs) else: instances = mcs._instances key = (mcs,) + tuple(args) try: return instances[key] except KeyError: # No cache entry for key exists, create a new one. return instances.setdefault(key, type.__call__(mcs, *args)) except TypeError: # An object in args cannot be hashed, always return # a new instance. return type.__call__(mcs, *args) class ArgumentParser(object): """Base class used to parse and convert arguments. The Parse() method checks to make sure that the string argument is a legal value and convert it to a native type. If the value cannot be converted, it should throw a 'ValueError' exception with a human readable explanation of why the value is illegal. Subclasses should also define a syntactic_help string which may be presented to the user to describe the form of the legal values. Argument parser classes must be stateless, since instances are cached and shared between flags. Initializer arguments are allowed, but all member variables must be derived from initializer arguments only. """ __metaclass__ = _ArgumentParserCache syntactic_help = "" def Parse(self, argument): """Default implementation: always returns its argument unmodified.""" return argument def Type(self): return 'string' def WriteCustomInfoInXMLFormat(self, outfile, indent): pass class ArgumentSerializer: """Base class for generating string representations of a flag value.""" def Serialize(self, value): return str(value) class ListSerializer(ArgumentSerializer): def __init__(self, list_sep): self.list_sep = list_sep def Serialize(self, value): return self.list_sep.join([str(x) for x in value]) # Flags validators def RegisterValidator(flag_name, checker, message='Flag validation failed', flag_values=FLAGS): """Adds a constraint, which will be enforced during program execution. The constraint is validated when flags are initially parsed, and after each change of the corresponding flag's value. Args: flag_name: string, name of the flag to be checked. checker: method to validate the flag. input - value of the corresponding flag (string, boolean, etc. This value will be passed to checker by the library). See file's docstring for examples. output - Boolean. Must return True if validator constraint is satisfied. If constraint is not satisfied, it should either return False or raise gflags_validators.Error(desired_error_message). message: error text to be shown to the user if checker returns False. If checker raises gflags_validators.Error, message from the raised Error will be shown. flag_values: FlagValues Raises: AttributeError: if flag_name is not registered as a valid flag name. """ flag_values.AddValidator(gflags_validators.SimpleValidator(flag_name, checker, message)) def MarkFlagAsRequired(flag_name, flag_values=FLAGS): """Ensure that flag is not None during program execution. Registers a flag validator, which will follow usual validator rules. Args: flag_name: string, name of the flag flag_values: FlagValues Raises: AttributeError: if flag_name is not registered as a valid flag name. """ RegisterValidator(flag_name, lambda value: value is not None, message='Flag --%s must be specified.' % flag_name, flag_values=flag_values) def _RegisterBoundsValidatorIfNeeded(parser, name, flag_values): """Enforce lower and upper bounds for numeric flags. Args: parser: NumericParser (either FloatParser or IntegerParser). Provides lower and upper bounds, and help text to display. name: string, name of the flag flag_values: FlagValues """ if parser.lower_bound is not None or parser.upper_bound is not None: def Checker(value): if value is not None and parser.IsOutsideBounds(value): message = '%s is not %s' % (value, parser.syntactic_help) raise gflags_validators.Error(message) return True RegisterValidator(name, Checker, flag_values=flag_values) # The DEFINE functions are explained in mode details in the module doc string. def DEFINE(parser, name, default, help, flag_values=FLAGS, serializer=None, **args): """Registers a generic Flag object. NOTE: in the docstrings of all DEFINE* functions, "registers" is short for "creates a new flag and registers it". Auxiliary function: clients should use the specialized DEFINE_<type> function instead. Args: parser: ArgumentParser that is used to parse the flag arguments. name: A string, the flag name. default: The default value of the flag. help: A help string. flag_values: FlagValues object the flag will be registered with. serializer: ArgumentSerializer that serializes the flag value. args: Dictionary with extra keyword args that are passes to the Flag __init__. """ DEFINE_flag(Flag(parser, serializer, name, default, help, **args), flag_values) def DEFINE_flag(flag, flag_values=FLAGS): """Registers a 'Flag' object with a 'FlagValues' object. By default, the global FLAGS 'FlagValue' object is used. Typical users will use one of the more specialized DEFINE_xxx functions, such as DEFINE_string or DEFINE_integer. But developers who need to create Flag objects themselves should use this function to register their flags. """ # copying the reference to flag_values prevents pychecker warnings fv = flag_values fv[flag.name] = flag # Tell flag_values who's defining the flag. if isinstance(flag_values, FlagValues): # Regarding the above isinstance test: some users pass funny # values of flag_values (e.g., {}) in order to avoid the flag # registration (in the past, there used to be a flag_values == # FLAGS test here) and redefine flags with the same name (e.g., # debug). To avoid breaking their code, we perform the # registration only if flag_values is a real FlagValues object. flag_values._RegisterFlagByModule(_GetCallingModule(), flag) def _InternalDeclareKeyFlags(flag_names, flag_values=FLAGS, key_flag_values=None): """Declares a flag as key for the calling module. Internal function. User code should call DECLARE_key_flag or ADOPT_module_key_flags instead. Args: flag_names: A list of strings that are names of already-registered Flag objects. flag_values: A FlagValues object that the flags listed in flag_names have registered with (the value of the flag_values argument from the DEFINE_* calls that defined those flags). This should almost never need to be overridden. key_flag_values: A FlagValues object that (among possibly many other things) keeps track of the key flags for each module. Default None means "same as flag_values". This should almost never need to be overridden. Raises: UnrecognizedFlagError: when we refer to a flag that was not defined yet. """ key_flag_values = key_flag_values or flag_values module = _GetCallingModule() for flag_name in flag_names: if flag_name not in flag_values: raise UnrecognizedFlagError(flag_name) flag = flag_values.FlagDict()[flag_name] key_flag_values._RegisterKeyFlagForModule(module, flag) def DECLARE_key_flag(flag_name, flag_values=FLAGS): """Declares one flag as key to the current module. Key flags are flags that are deemed really important for a module. They are important when listing help messages; e.g., if the --helpshort command-line flag is used, then only the key flags of the main module are listed (instead of all flags, as in the case of --help). Sample usage: flags.DECLARED_key_flag('flag_1') Args: flag_name: A string, the name of an already declared flag. (Redeclaring flags as key, including flags implicitly key because they were declared in this module, is a no-op.) flag_values: A FlagValues object. This should almost never need to be overridden. """ if flag_name in _SPECIAL_FLAGS: # Take care of the special flags, e.g., --flagfile, --undefok. # These flags are defined in _SPECIAL_FLAGS, and are treated # specially during flag parsing, taking precedence over the # user-defined flags. _InternalDeclareKeyFlags([flag_name], flag_values=_SPECIAL_FLAGS, key_flag_values=flag_values) return _InternalDeclareKeyFlags([flag_name], flag_values=flag_values) def ADOPT_module_key_flags(module, flag_values=FLAGS): """Declares that all flags key to a module are key to the current module. Args: module: A module object. flag_values: A FlagValues object. This should almost never need to be overridden. Raises: FlagsError: When given an argument that is a module name (a string), instead of a module object. """ # NOTE(salcianu): an even better test would be if not # isinstance(module, types.ModuleType) but I didn't want to import # types for such a tiny use. if isinstance(module, str): raise FlagsError('Received module name %s; expected a module object.' % module) _InternalDeclareKeyFlags( [f.name for f in flag_values._GetKeyFlagsForModule(module.__name__)], flag_values=flag_values) # If module is this flag module, take _SPECIAL_FLAGS into account. if module == _GetThisModuleObjectAndName()[0]: _InternalDeclareKeyFlags( # As we associate flags with _GetCallingModule(), the special # flags defined in this module are incorrectly registered with # a different module. So, we can't use _GetKeyFlagsForModule. # Instead, we take all flags from _SPECIAL_FLAGS (a private # FlagValues, where no other module should register flags). [f.name for f in _SPECIAL_FLAGS.FlagDict().values()], flag_values=_SPECIAL_FLAGS, key_flag_values=flag_values) # # STRING FLAGS # def DEFINE_string(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value can be any string.""" parser = ArgumentParser() serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) # # BOOLEAN FLAGS # # and the special HELP flags. class BooleanParser(ArgumentParser): """Parser of boolean values.""" def Convert(self, argument): """Converts the argument to a boolean; raise ValueError on errors.""" if type(argument) == str: if argument.lower() in ['true', 't', '1']: return True elif argument.lower() in ['false', 'f', '0']: return False bool_argument = bool(argument) if argument == bool_argument: # The argument is a valid boolean (True, False, 0, or 1), and not just # something that always converts to bool (list, string, int, etc.). return bool_argument raise ValueError('Non-boolean argument to boolean flag', argument) def Parse(self, argument): val = self.Convert(argument) return val def Type(self): return 'bool' class BooleanFlag(Flag): """Basic boolean flag. Boolean flags do not take any arguments, and their value is either True (1) or False (0). The false value is specified on the command line by prepending the word 'no' to either the long or the short flag name. For example, if a Boolean flag was created whose long name was 'update' and whose short name was 'x', then this flag could be explicitly unset through either --noupdate or --nox. """ def __init__(self, name, default, help, short_name=None, **args): p = BooleanParser() Flag.__init__(self, p, None, name, default, help, short_name, 1, **args) if not self.help: self.help = "a boolean value" def DEFINE_boolean(name, default, help, flag_values=FLAGS, **args): """Registers a boolean flag. Such a boolean flag does not take an argument. If a user wants to specify a false value explicitly, the long option beginning with 'no' must be used: i.e. --noflag This flag will have a value of None, True or False. None is possible if default=None and the user does not specify the flag on the command line. """ DEFINE_flag(BooleanFlag(name, default, help, **args), flag_values) # Match C++ API to unconfuse C++ people. DEFINE_bool = DEFINE_boolean class HelpFlag(BooleanFlag): """ HelpFlag is a special boolean flag that prints usage information and raises a SystemExit exception if it is ever found in the command line arguments. Note this is called with allow_override=1, so other apps can define their own --help flag, replacing this one, if they want. """ def __init__(self): BooleanFlag.__init__(self, "help", 0, "show this help", short_name="?", allow_override=1) def Parse(self, arg): if arg: doc = sys.modules["__main__"].__doc__ flags = str(FLAGS) print doc or ("\nUSAGE: %s [flags]\n" % sys.argv[0]) if flags: print "flags:" print flags sys.exit(1) class HelpXMLFlag(BooleanFlag): """Similar to HelpFlag, but generates output in XML format.""" def __init__(self): BooleanFlag.__init__(self, 'helpxml', False, 'like --help, but generates XML output', allow_override=1) def Parse(self, arg): if arg: FLAGS.WriteHelpInXMLFormat(sys.stdout) sys.exit(1) class HelpshortFlag(BooleanFlag): """ HelpshortFlag is a special boolean flag that prints usage information for the "main" module, and rasies a SystemExit exception if it is ever found in the command line arguments. Note this is called with allow_override=1, so other apps can define their own --helpshort flag, replacing this one, if they want. """ def __init__(self): BooleanFlag.__init__(self, "helpshort", 0, "show usage only for this module", allow_override=1) def Parse(self, arg): if arg: doc = sys.modules["__main__"].__doc__ flags = FLAGS.MainModuleHelp() print doc or ("\nUSAGE: %s [flags]\n" % sys.argv[0]) if flags: print "flags:" print flags sys.exit(1) # # Numeric parser - base class for Integer and Float parsers # class NumericParser(ArgumentParser): """Parser of numeric values. Parsed value may be bounded to a given upper and lower bound. """ def IsOutsideBounds(self, val): return ((self.lower_bound is not None and val < self.lower_bound) or (self.upper_bound is not None and val > self.upper_bound)) def Parse(self, argument): val = self.Convert(argument) if self.IsOutsideBounds(val): raise ValueError("%s is not %s" % (val, self.syntactic_help)) return val def WriteCustomInfoInXMLFormat(self, outfile, indent): if self.lower_bound is not None: _WriteSimpleXMLElement(outfile, 'lower_bound', self.lower_bound, indent) if self.upper_bound is not None: _WriteSimpleXMLElement(outfile, 'upper_bound', self.upper_bound, indent) def Convert(self, argument): """Default implementation: always returns its argument unmodified.""" return argument # End of Numeric Parser # # FLOAT FLAGS # class FloatParser(NumericParser): """Parser of floating point values. Parsed value may be bounded to a given upper and lower bound. """ number_article = "a" number_name = "number" syntactic_help = " ".join((number_article, number_name)) def __init__(self, lower_bound=None, upper_bound=None): super(FloatParser, self).__init__() self.lower_bound = lower_bound self.upper_bound = upper_bound sh = self.syntactic_help if lower_bound is not None and upper_bound is not None: sh = ("%s in the range [%s, %s]" % (sh, lower_bound, upper_bound)) elif lower_bound == 0: sh = "a non-negative %s" % self.number_name elif upper_bound == 0: sh = "a non-positive %s" % self.number_name elif upper_bound is not None: sh = "%s <= %s" % (self.number_name, upper_bound) elif lower_bound is not None: sh = "%s >= %s" % (self.number_name, lower_bound) self.syntactic_help = sh def Convert(self, argument): """Converts argument to a float; raises ValueError on errors.""" return float(argument) def Type(self): return 'float' # End of FloatParser def DEFINE_float(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value must be a float. If lower_bound or upper_bound are set, then this flag must be within the given range. """ parser = FloatParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) _RegisterBoundsValidatorIfNeeded(parser, name, flag_values=flag_values) # # INTEGER FLAGS # class IntegerParser(NumericParser): """Parser of an integer value. Parsed value may be bounded to a given upper and lower bound. """ number_article = "an" number_name = "integer" syntactic_help = " ".join((number_article, number_name)) def __init__(self, lower_bound=None, upper_bound=None): super(IntegerParser, self).__init__() self.lower_bound = lower_bound self.upper_bound = upper_bound sh = self.syntactic_help if lower_bound is not None and upper_bound is not None: sh = ("%s in the range [%s, %s]" % (sh, lower_bound, upper_bound)) elif lower_bound == 1: sh = "a positive %s" % self.number_name elif upper_bound == -1: sh = "a negative %s" % self.number_name elif lower_bound == 0: sh = "a non-negative %s" % self.number_name elif upper_bound == 0: sh = "a non-positive %s" % self.number_name elif upper_bound is not None: sh = "%s <= %s" % (self.number_name, upper_bound) elif lower_bound is not None: sh = "%s >= %s" % (self.number_name, lower_bound) self.syntactic_help = sh def Convert(self, argument): __pychecker__ = 'no-returnvalues' if type(argument) == str: base = 10 if len(argument) > 2 and argument[0] == "0" and argument[1] == "x": base = 16 try: return int(argument, base) # ValueError is thrown when argument is a string, and overflows an int. except ValueError: return long(argument, base) else: try: return int(argument) # OverflowError is thrown when argument is numeric, and overflows an int. except OverflowError: return long(argument) def Type(self): return 'int' def DEFINE_integer(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value must be an integer. If lower_bound, or upper_bound are set, then this flag must be within the given range. """ parser = IntegerParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE(parser, name, default, help, flag_values, serializer, **args) _RegisterBoundsValidatorIfNeeded(parser, name, flag_values=flag_values) # # ENUM FLAGS # class EnumParser(ArgumentParser): """Parser of a string enum value (a string value from a given set). If enum_values (see below) is not specified, any string is allowed. """ def __init__(self, enum_values=None): super(EnumParser, self).__init__() self.enum_values = enum_values def Parse(self, argument): if self.enum_values and argument not in self.enum_values: raise ValueError("value should be one of <%s>" % "|".join(self.enum_values)) return argument def Type(self): return 'string enum' class EnumFlag(Flag): """Basic enum flag; its value can be any string from list of enum_values.""" def __init__(self, name, default, help, enum_values=None, short_name=None, **args): enum_values = enum_values or [] p = EnumParser(enum_values) g = ArgumentSerializer() Flag.__init__(self, p, g, name, default, help, short_name, **args) if not self.help: self.help = "an enum string" self.help = "<%s>: %s" % ("|".join(enum_values), self.help) def _WriteCustomInfoInXMLFormat(self, outfile, indent): for enum_value in self.parser.enum_values: _WriteSimpleXMLElement(outfile, 'enum_value', enum_value, indent) def DEFINE_enum(name, default, enum_values, help, flag_values=FLAGS, **args): """Registers a flag whose value can be any string from enum_values.""" DEFINE_flag(EnumFlag(name, default, help, enum_values, ** args), flag_values) # # LIST FLAGS # class BaseListParser(ArgumentParser): """Base class for a parser of lists of strings. To extend, inherit from this class; from the subclass __init__, call BaseListParser.__init__(self, token, name) where token is a character used to tokenize, and name is a description of the separator. """ def __init__(self, token=None, name=None): assert name super(BaseListParser, self).__init__() self._token = token self._name = name self.syntactic_help = "a %s separated list" % self._name def Parse(self, argument): if isinstance(argument, list): return argument elif argument == '': return [] else: return [s.strip() for s in argument.split(self._token)] def Type(self): return '%s separated list of strings' % self._name class ListParser(BaseListParser): """Parser for a comma-separated list of strings.""" def __init__(self): BaseListParser.__init__(self, ',', 'comma') def WriteCustomInfoInXMLFormat(self, outfile, indent): BaseListParser.WriteCustomInfoInXMLFormat(self, outfile, indent) _WriteSimpleXMLElement(outfile, 'list_separator', repr(','), indent) class WhitespaceSeparatedListParser(BaseListParser): """Parser for a whitespace-separated list of strings.""" def __init__(self): BaseListParser.__init__(self, None, 'whitespace') def WriteCustomInfoInXMLFormat(self, outfile, indent): BaseListParser.WriteCustomInfoInXMLFormat(self, outfile, indent) separators = list(string.whitespace) separators.sort() for ws_char in string.whitespace: _WriteSimpleXMLElement(outfile, 'list_separator', repr(ws_char), indent) def DEFINE_list(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value is a comma-separated list of strings.""" parser = ListParser() serializer = ListSerializer(',') DEFINE(parser, name, default, help, flag_values, serializer, **args) def DEFINE_spaceseplist(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value is a whitespace-separated list of strings. Any whitespace can be used as a separator. """ parser = WhitespaceSeparatedListParser() serializer = ListSerializer(' ') DEFINE(parser, name, default, help, flag_values, serializer, **args) # # MULTI FLAGS # class MultiFlag(Flag): """A flag that can appear multiple time on the command-line. The value of such a flag is a list that contains the individual values from all the appearances of that flag on the command-line. See the __doc__ for Flag for most behavior of this class. Only differences in behavior are described here: * The default value may be either a single value or a list of values. A single value is interpreted as the [value] singleton list. * The value of the flag is always a list, even if the option was only supplied once, and even if the default value is a single value """ def __init__(self, *args, **kwargs): Flag.__init__(self, *args, **kwargs) self.help += ';\n repeat this option to specify a list of values' def Parse(self, arguments): """Parses one or more arguments with the installed parser. Args: arguments: a single argument or a list of arguments (typically a list of default values); a single argument is converted internally into a list containing one item. """ if not isinstance(arguments, list): # Default value may be a list of values. Most other arguments # will not be, so convert them into a single-item list to make # processing simpler below. arguments = [arguments] if self.present: # keep a backup reference to list of previously supplied option values values = self.value else: # "erase" the defaults with an empty list values = [] for item in arguments: # have Flag superclass parse argument, overwriting self.value reference Flag.Parse(self, item) # also increments self.present values.append(self.value) # put list of option values back in the 'value' attribute self.value = values def Serialize(self): if not self.serializer: raise FlagsError("Serializer not present for flag %s" % self.name) if self.value is None: return '' s = '' multi_value = self.value for self.value in multi_value: if s: s += ' ' s += Flag.Serialize(self) self.value = multi_value return s def Type(self): return 'multi ' + self.parser.Type() def DEFINE_multi(parser, serializer, name, default, help, flag_values=FLAGS, **args): """Registers a generic MultiFlag that parses its args with a given parser. Auxiliary function. Normal users should NOT use it directly. Developers who need to create their own 'Parser' classes for options which can appear multiple times can call this module function to register their flags. """ DEFINE_flag(MultiFlag(parser, serializer, name, default, help, **args), flag_values) def DEFINE_multistring(name, default, help, flag_values=FLAGS, **args): """Registers a flag whose value can be a list of any strings. Use the flag on the command line multiple times to place multiple string values into the list. The 'default' may be a single string (which will be converted into a single-element list) or a list of strings. """ parser = ArgumentParser() serializer = ArgumentSerializer() DEFINE_multi(parser, serializer, name, default, help, flag_values, **args) def DEFINE_multi_int(name, default, help, lower_bound=None, upper_bound=None, flag_values=FLAGS, **args): """Registers a flag whose value can be a list of arbitrary integers. Use the flag on the command line multiple times to place multiple integer values into the list. The 'default' may be a single integer (which will be converted into a single-element list) or a list of integers. """ parser = IntegerParser(lower_bound, upper_bound) serializer = ArgumentSerializer() DEFINE_multi(parser, serializer, name, default, help, flag_values, **args) # Now register the flags that we want to exist in all applications. # These are all defined with allow_override=1, so user-apps can use # these flagnames for their own purposes, if they want. DEFINE_flag(HelpFlag()) DEFINE_flag(HelpshortFlag()) DEFINE_flag(HelpXMLFlag()) # Define special flags here so that help may be generated for them. # NOTE: Please do NOT use _SPECIAL_FLAGS from outside this module. _SPECIAL_FLAGS = FlagValues() DEFINE_string( 'flagfile', "", "Insert flag definitions from the given file into the command line.", _SPECIAL_FLAGS) DEFINE_string( 'undefok', "", "comma-separated list of flag names that it is okay to specify " "on the command line even if the program does not define a flag " "with that name. IMPORTANT: flags in this list that have " "arguments MUST use the --flag=value format.", _SPECIAL_FLAGS)
Python
#!/usr/bin/python2.4 # # -*- coding: utf-8 -*- # # Copyright 2011 Google Inc. All Rights Reserved. """Simple command-line example for Google Prediction API. Command-line application that trains on some data. This sample does the same thing as the Hello Prediction! example. http://code.google.com/apis/predict/docs/hello_world.html """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' import httplib2 import pprint import time from apiclient.discovery import build from oauth2client.client import OAuth2WebServerFlow from oauth2client.file import Storage from oauth2client.tools import run # Uncomment to get low level HTTP logging #httplib2.debuglevel = 4 # Name of Google Storage bucket/object that contains the training data OBJECT_NAME = "apiclient-prediction-sample/prediction_models/languages" def main(): storage = Storage('prediction.dat') credentials = storage.get() if credentials is None or credentials.invalid == True: flow = OAuth2WebServerFlow( # You MUST put in your client id and secret here for this sample to # work. Visit https://code.google.com/apis/console to get your client # credentials. client_id='<Put Your Client ID Here>', client_secret='<Put Your Client Secret Here>', scope='https://www.googleapis.com/auth/prediction', user_agent='prediction-cmdline-sample/1.0', xoauth_displayname='Prediction Example App') credentials = run(flow, storage) http = httplib2.Http() http = credentials.authorize(http) service = build("prediction", "v1.1", http=http) # Start training on a data set train = service.training() start = train.insert(data=OBJECT_NAME, body={}).execute() print 'Started training' pprint.pprint(start) # Wait for the training to complete while 1: status = train.get(data=OBJECT_NAME).execute() pprint.pprint(status) if 'accuracy' in status['modelinfo']: break print 'Waiting for training to complete.' time.sleep(10) print 'Training is complete' # Now make a prediction using that training body = {'input': {'mixture': ["mucho bueno"]}} prediction = service.predict(body=body, data=OBJECT_NAME).execute() print 'The prediction is:' pprint.pprint(prediction) if __name__ == '__main__': main()
Python
#!/usr/bin/python2.4 # # -*- coding: utf-8 -*- # # Copyright 2011 Google Inc. All Rights Reserved. """Simple command-line example for Google Prediction API. Command-line application that trains on some data. This sample does the same thing as the Hello Prediction! example. http://code.google.com/apis/predict/docs/hello_world.html """ __author__ = 'jcgregorio@google.com (Joe Gregorio)' import httplib2 import pprint import time from apiclient.discovery import build from oauth2client.client import OAuth2WebServerFlow from oauth2client.file import Storage from oauth2client.tools import run # Uncomment to get low level HTTP logging #httplib2.debuglevel = 4 # Name of Google Storage bucket/object that contains the training data OBJECT_NAME = "apiclient-prediction-sample/prediction_models/languages" def main(): storage = Storage('prediction.dat') credentials = storage.get() if credentials is None or credentials.invalid == True: flow = OAuth2WebServerFlow( # You MUST put in your client id and secret here for this sample to # work. Visit https://code.google.com/apis/console to get your client # credentials. client_id='<Put Your Client ID Here>', client_secret='<Put Your Client Secret Here>', scope='https://www.googleapis.com/auth/prediction', user_agent='prediction-cmdline-sample/1.0', xoauth_displayname='Prediction Example App') credentials = run(flow, storage) http = httplib2.Http() http = credentials.authorize(http) service = build("prediction", "v1.1", http=http) # Start training on a data set train = service.training() start = train.insert(data=OBJECT_NAME, body={}).execute() print 'Started training' pprint.pprint(start) # Wait for the training to complete while 1: status = train.get(data=OBJECT_NAME).execute() pprint.pprint(status) if 'accuracy' in status['modelinfo']: break print 'Waiting for training to complete.' time.sleep(10) print 'Training is complete' # Now make a prediction using that training body = {'input': {'mixture': ["mucho bueno"]}} prediction = service.predict(body=body, data=OBJECT_NAME).execute() print 'The prediction is:' pprint.pprint(prediction) if __name__ == '__main__': main()
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import pickle import base64 from django.contrib import admin from django.contrib.auth.models import User from django.db import models from oauth2client.django_orm import FlowField from oauth2client.django_orm import CredentialsField # The Flow could also be stored in memcache since it is short lived. class FlowModel(models.Model): id = models.ForeignKey(User, primary_key=True) flow = FlowField() class CredentialsModel(models.Model): id = models.ForeignKey(User, primary_key=True) credential = CredentialsField() class CredentialsAdmin(admin.ModelAdmin): pass class FlowAdmin(admin.ModelAdmin): pass admin.site.register(CredentialsModel, CredentialsAdmin) admin.site.register(FlowModel, FlowAdmin)
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""" This file demonstrates two different styles of tests (one doctest and one unittest). These will both pass when you run "manage.py test". Replace these with more appropriate tests for your application. """ from django.test import TestCase class SimpleTest(TestCase): def test_basic_addition(self): """ Tests that 1 + 1 always equals 2. """ self.failUnlessEqual(1 + 1, 2) __test__ = {"doctest": """ Another way to test that 1 + 1 is equal to 2. >>> 1 + 1 == 2 True """}
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import os import logging import httplib2 from django.http import HttpResponse from django.core.urlresolvers import reverse from django.contrib.auth.decorators import login_required from oauth2client.django_orm import Storage from oauth2client.client import OAuth2WebServerFlow from django_sample.buzz.models import CredentialsModel from django_sample.buzz.models import FlowModel from apiclient.discovery import build from django.http import HttpResponseRedirect from django.shortcuts import render_to_response STEP2_URI = 'http://localhost:8000/auth_return' @login_required def index(request): storage = Storage(CredentialsModel, 'id', request.user, 'credential') credential = storage.get() if credential is None or credential.invalid == True: flow = OAuth2WebServerFlow( client_id='887851474342.apps.googleusercontent.com', client_secret='6V9MHBUQqOQtxI7uXPIEnV8e', scope='https://www.googleapis.com/auth/buzz', user_agent='buzz-django-sample/1.0', ) authorize_url = flow.step1_get_authorize_url(STEP2_URI) f = FlowModel(id=request.user, flow=flow) f.save() return HttpResponseRedirect(authorize_url) else: http = httplib2.Http() http = credential.authorize(http) service = build("buzz", "v1", http=http) activities = service.activities() activitylist = activities.list(scope='@consumption', userId='@me').execute() logging.info(activitylist) return render_to_response('buzz/welcome.html', { 'activitylist': activitylist, }) @login_required def auth_return(request): try: f = FlowModel.objects.get(id=request.user) credential = f.flow.step2_exchange(request.REQUEST) storage = Storage(CredentialsModel, 'id', request.user, 'credential') storage.put(credential) f.delete() return HttpResponseRedirect("/") except FlowModel.DoesNotExist: pass
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