| | """More comprehensive traceback formatting for Python scripts. |
| | |
| | To enable this module, do: |
| | |
| | import cgitb; cgitb.enable() |
| | |
| | at the top of your script. The optional arguments to enable() are: |
| | |
| | display - if true, tracebacks are displayed in the web browser |
| | logdir - if set, tracebacks are written to files in this directory |
| | context - number of lines of source code to show for each stack frame |
| | format - 'text' or 'html' controls the output format |
| | |
| | By default, tracebacks are displayed but not saved, the context is 5 lines |
| | and the output format is 'html' (for backwards compatibility with the |
| | original use of this module) |
| | |
| | Alternatively, if you have caught an exception and want cgitb to display it |
| | for you, call cgitb.handler(). The optional argument to handler() is a |
| | 3-item tuple (etype, evalue, etb) just like the value of sys.exc_info(). |
| | The default handler displays output as HTML. |
| | |
| | """ |
| | import inspect |
| | import keyword |
| | import linecache |
| | import os |
| | import pydoc |
| | import sys |
| | import tempfile |
| | import time |
| | import tokenize |
| | import traceback |
| |
|
| | def reset(): |
| | """Return a string that resets the CGI and browser to a known state.""" |
| | return '''<!--: spam |
| | Content-Type: text/html |
| | |
| | <body bgcolor="#f0f0f8"><font color="#f0f0f8" size="-5"> --> |
| | <body bgcolor="#f0f0f8"><font color="#f0f0f8" size="-5"> --> --> |
| | </font> </font> </font> </script> </object> </blockquote> </pre> |
| | </table> </table> </table> </table> </table> </font> </font> </font>''' |
| |
|
| | __UNDEF__ = [] |
| | def small(text): |
| | if text: |
| | return '<small>' + text + '</small>' |
| | else: |
| | return '' |
| |
|
| | def strong(text): |
| | if text: |
| | return '<strong>' + text + '</strong>' |
| | else: |
| | return '' |
| |
|
| | def grey(text): |
| | if text: |
| | return '<font color="#909090">' + text + '</font>' |
| | else: |
| | return '' |
| |
|
| | def lookup(name, frame, locals): |
| | """Find the value for a given name in the given environment.""" |
| | if name in locals: |
| | return 'local', locals[name] |
| | if name in frame.f_globals: |
| | return 'global', frame.f_globals[name] |
| | if '__builtins__' in frame.f_globals: |
| | builtins = frame.f_globals['__builtins__'] |
| | if type(builtins) is type({}): |
| | if name in builtins: |
| | return 'builtin', builtins[name] |
| | else: |
| | if hasattr(builtins, name): |
| | return 'builtin', getattr(builtins, name) |
| | return None, __UNDEF__ |
| |
|
| | def scanvars(reader, frame, locals): |
| | """Scan one logical line of Python and look up values of variables used.""" |
| | vars, lasttoken, parent, prefix, value = [], None, None, '', __UNDEF__ |
| | for ttype, token, start, end, line in tokenize.generate_tokens(reader): |
| | if ttype == tokenize.NEWLINE: break |
| | if ttype == tokenize.NAME and token not in keyword.kwlist: |
| | if lasttoken == '.': |
| | if parent is not __UNDEF__: |
| | value = getattr(parent, token, __UNDEF__) |
| | vars.append((prefix + token, prefix, value)) |
| | else: |
| | where, value = lookup(token, frame, locals) |
| | vars.append((token, where, value)) |
| | elif token == '.': |
| | prefix += lasttoken + '.' |
| | parent = value |
| | else: |
| | parent, prefix = None, '' |
| | lasttoken = token |
| | return vars |
| |
|
| | def html(einfo, context=5): |
| | """Return a nice HTML document describing a given traceback.""" |
| | etype, evalue, etb = einfo |
| | if isinstance(etype, type): |
| | etype = etype.__name__ |
| | pyver = 'Python ' + sys.version.split()[0] + ': ' + sys.executable |
| | date = time.ctime(time.time()) |
| | head = '<body bgcolor="#f0f0f8">' + pydoc.html.heading( |
| | '<big><big>%s</big></big>' % |
| | strong(pydoc.html.escape(str(etype))), |
| | '#ffffff', '#6622aa', pyver + '<br>' + date) + ''' |
| | <p>A problem occurred in a Python script. Here is the sequence of |
| | function calls leading up to the error, in the order they occurred.</p>''' |
| |
|
| | indent = '<tt>' + small(' ' * 5) + ' </tt>' |
| | frames = [] |
| | records = inspect.getinnerframes(etb, context) |
| | for frame, file, lnum, func, lines, index in records: |
| | if file: |
| | file = os.path.abspath(file) |
| | link = '<a href="file://%s">%s</a>' % (file, pydoc.html.escape(file)) |
| | else: |
| | file = link = '?' |
| | args, varargs, varkw, locals = inspect.getargvalues(frame) |
| | call = '' |
| | if func != '?': |
| | call = 'in ' + strong(pydoc.html.escape(func)) |
| | if func != "<module>": |
| | call += inspect.formatargvalues(args, varargs, varkw, locals, |
| | formatvalue=lambda value: '=' + pydoc.html.repr(value)) |
| |
|
| | highlight = {} |
| | def reader(lnum=[lnum]): |
| | highlight[lnum[0]] = 1 |
| | try: return linecache.getline(file, lnum[0]) |
| | finally: lnum[0] += 1 |
| | vars = scanvars(reader, frame, locals) |
| |
|
| | rows = ['<tr><td bgcolor="#d8bbff">%s%s %s</td></tr>' % |
| | ('<big> </big>', link, call)] |
| | if index is not None: |
| | i = lnum - index |
| | for line in lines: |
| | num = small(' ' * (5-len(str(i))) + str(i)) + ' ' |
| | if i in highlight: |
| | line = '<tt>=>%s%s</tt>' % (num, pydoc.html.preformat(line)) |
| | rows.append('<tr><td bgcolor="#ffccee">%s</td></tr>' % line) |
| | else: |
| | line = '<tt> %s%s</tt>' % (num, pydoc.html.preformat(line)) |
| | rows.append('<tr><td>%s</td></tr>' % grey(line)) |
| | i += 1 |
| |
|
| | done, dump = {}, [] |
| | for name, where, value in vars: |
| | if name in done: continue |
| | done[name] = 1 |
| | if value is not __UNDEF__: |
| | if where in ('global', 'builtin'): |
| | name = ('<em>%s</em> ' % where) + strong(name) |
| | elif where == 'local': |
| | name = strong(name) |
| | else: |
| | name = where + strong(name.split('.')[-1]) |
| | dump.append('%s = %s' % (name, pydoc.html.repr(value))) |
| | else: |
| | dump.append(name + ' <em>undefined</em>') |
| |
|
| | rows.append('<tr><td>%s</td></tr>' % small(grey(', '.join(dump)))) |
| | frames.append(''' |
| | <table width="100%%" cellspacing=0 cellpadding=0 border=0> |
| | %s</table>''' % '\n'.join(rows)) |
| |
|
| | exception = ['<p>%s: %s' % (strong(pydoc.html.escape(str(etype))), |
| | pydoc.html.escape(str(evalue)))] |
| | for name in dir(evalue): |
| | if name[:1] == '_': continue |
| | value = pydoc.html.repr(getattr(evalue, name)) |
| | exception.append('\n<br>%s%s =\n%s' % (indent, name, value)) |
| |
|
| | return head + ''.join(frames) + ''.join(exception) + ''' |
| | |
| | |
| | <!-- The above is a description of an error in a Python program, formatted |
| | for a web browser because the 'cgitb' module was enabled. In case you |
| | are not reading this in a web browser, here is the original traceback: |
| | |
| | %s |
| | --> |
| | ''' % pydoc.html.escape( |
| | ''.join(traceback.format_exception(etype, evalue, etb))) |
| |
|
| | def text(einfo, context=5): |
| | """Return a plain text document describing a given traceback.""" |
| | etype, evalue, etb = einfo |
| | if isinstance(etype, type): |
| | etype = etype.__name__ |
| | pyver = 'Python ' + sys.version.split()[0] + ': ' + sys.executable |
| | date = time.ctime(time.time()) |
| | head = "%s\n%s\n%s\n" % (str(etype), pyver, date) + ''' |
| | A problem occurred in a Python script. Here is the sequence of |
| | function calls leading up to the error, in the order they occurred. |
| | ''' |
| |
|
| | frames = [] |
| | records = inspect.getinnerframes(etb, context) |
| | for frame, file, lnum, func, lines, index in records: |
| | file = file and os.path.abspath(file) or '?' |
| | args, varargs, varkw, locals = inspect.getargvalues(frame) |
| | call = '' |
| | if func != '?': |
| | call = 'in ' + func |
| | if func != "<module>": |
| | call += inspect.formatargvalues(args, varargs, varkw, locals, |
| | formatvalue=lambda value: '=' + pydoc.text.repr(value)) |
| |
|
| | highlight = {} |
| | def reader(lnum=[lnum]): |
| | highlight[lnum[0]] = 1 |
| | try: return linecache.getline(file, lnum[0]) |
| | finally: lnum[0] += 1 |
| | vars = scanvars(reader, frame, locals) |
| |
|
| | rows = [' %s %s' % (file, call)] |
| | if index is not None: |
| | i = lnum - index |
| | for line in lines: |
| | num = '%5d ' % i |
| | rows.append(num+line.rstrip()) |
| | i += 1 |
| |
|
| | done, dump = {}, [] |
| | for name, where, value in vars: |
| | if name in done: continue |
| | done[name] = 1 |
| | if value is not __UNDEF__: |
| | if where == 'global': name = 'global ' + name |
| | elif where != 'local': name = where + name.split('.')[-1] |
| | dump.append('%s = %s' % (name, pydoc.text.repr(value))) |
| | else: |
| | dump.append(name + ' undefined') |
| |
|
| | rows.append('\n'.join(dump)) |
| | frames.append('\n%s\n' % '\n'.join(rows)) |
| |
|
| | exception = ['%s: %s' % (str(etype), str(evalue))] |
| | for name in dir(evalue): |
| | value = pydoc.text.repr(getattr(evalue, name)) |
| | exception.append('\n%s%s = %s' % (" "*4, name, value)) |
| |
|
| | return head + ''.join(frames) + ''.join(exception) + ''' |
| | |
| | The above is a description of an error in a Python program. Here is |
| | the original traceback: |
| | |
| | %s |
| | ''' % ''.join(traceback.format_exception(etype, evalue, etb)) |
| |
|
| | class Hook: |
| | """A hook to replace sys.excepthook that shows tracebacks in HTML.""" |
| |
|
| | def __init__(self, display=1, logdir=None, context=5, file=None, |
| | format="html"): |
| | self.display = display |
| | self.logdir = logdir |
| | self.context = context |
| | self.file = file or sys.stdout |
| | self.format = format |
| |
|
| | def __call__(self, etype, evalue, etb): |
| | self.handle((etype, evalue, etb)) |
| |
|
| | def handle(self, info=None): |
| | info = info or sys.exc_info() |
| | if self.format == "html": |
| | self.file.write(reset()) |
| |
|
| | formatter = (self.format=="html") and html or text |
| | plain = False |
| | try: |
| | doc = formatter(info, self.context) |
| | except: |
| | doc = ''.join(traceback.format_exception(*info)) |
| | plain = True |
| |
|
| | if self.display: |
| | if plain: |
| | doc = pydoc.html.escape(doc) |
| | self.file.write('<pre>' + doc + '</pre>\n') |
| | else: |
| | self.file.write(doc + '\n') |
| | else: |
| | self.file.write('<p>A problem occurred in a Python script.\n') |
| |
|
| | if self.logdir is not None: |
| | suffix = ['.txt', '.html'][self.format=="html"] |
| | (fd, path) = tempfile.mkstemp(suffix=suffix, dir=self.logdir) |
| |
|
| | try: |
| | with os.fdopen(fd, 'w') as file: |
| | file.write(doc) |
| | msg = '%s contains the description of this error.' % path |
| | except: |
| | msg = 'Tried to save traceback to %s, but failed.' % path |
| |
|
| | if self.format == 'html': |
| | self.file.write('<p>%s</p>\n' % msg) |
| | else: |
| | self.file.write(msg + '\n') |
| | try: |
| | self.file.flush() |
| | except: pass |
| |
|
| | handler = Hook().handle |
| | def enable(display=1, logdir=None, context=5, format="html"): |
| | """Install an exception handler that formats tracebacks as HTML. |
| | |
| | The optional argument 'display' can be set to 0 to suppress sending the |
| | traceback to the browser, and 'logdir' can be set to a directory to cause |
| | tracebacks to be written to files there.""" |
| | sys.excepthook = Hook(display=display, logdir=logdir, |
| | context=context, format=format) |
| |
|
