| | """Manage HTTP Response Headers |
| | |
| | Much of this module is red-handedly pilfered from email.message in the stdlib, |
| | so portions are Copyright (C) 2001,2002 Python Software Foundation, and were |
| | written by Barry Warsaw. |
| | """ |
| |
|
| | |
| | |
| | import re |
| | tspecials = re.compile(r'[ \(\)<>@,;:\\"/\[\]\?=]') |
| |
|
| | def _formatparam(param, value=None, quote=1): |
| | """Convenience function to format and return a key=value pair. |
| | |
| | This will quote the value if needed or if quote is true. |
| | """ |
| | if value is not None and len(value) > 0: |
| | if quote or tspecials.search(value): |
| | value = value.replace('\\', '\\\\').replace('"', r'\"') |
| | return '%s="%s"' % (param, value) |
| | else: |
| | return '%s=%s' % (param, value) |
| | else: |
| | return param |
| |
|
| |
|
| | class Headers: |
| | """Manage a collection of HTTP response headers""" |
| |
|
| | def __init__(self, headers=None): |
| | headers = headers if headers is not None else [] |
| | if type(headers) is not list: |
| | raise TypeError("Headers must be a list of name/value tuples") |
| | self._headers = headers |
| | if __debug__: |
| | for k, v in headers: |
| | self._convert_string_type(k) |
| | self._convert_string_type(v) |
| |
|
| | def _convert_string_type(self, value): |
| | """Convert/check value type.""" |
| | if type(value) is str: |
| | return value |
| | raise AssertionError("Header names/values must be" |
| | " of type str (got {0})".format(repr(value))) |
| |
|
| | def __len__(self): |
| | """Return the total number of headers, including duplicates.""" |
| | return len(self._headers) |
| |
|
| | def __setitem__(self, name, val): |
| | """Set the value of a header.""" |
| | del self[name] |
| | self._headers.append( |
| | (self._convert_string_type(name), self._convert_string_type(val))) |
| |
|
| | def __delitem__(self,name): |
| | """Delete all occurrences of a header, if present. |
| | |
| | Does *not* raise an exception if the header is missing. |
| | """ |
| | name = self._convert_string_type(name.lower()) |
| | self._headers[:] = [kv for kv in self._headers if kv[0].lower() != name] |
| |
|
| | def __getitem__(self,name): |
| | """Get the first header value for 'name' |
| | |
| | Return None if the header is missing instead of raising an exception. |
| | |
| | Note that if the header appeared multiple times, the first exactly which |
| | occurrence gets returned is undefined. Use getall() to get all |
| | the values matching a header field name. |
| | """ |
| | return self.get(name) |
| |
|
| | def __contains__(self, name): |
| | """Return true if the message contains the header.""" |
| | return self.get(name) is not None |
| |
|
| |
|
| | def get_all(self, name): |
| | """Return a list of all the values for the named field. |
| | |
| | These will be sorted in the order they appeared in the original header |
| | list or were added to this instance, and may contain duplicates. Any |
| | fields deleted and re-inserted are always appended to the header list. |
| | If no fields exist with the given name, returns an empty list. |
| | """ |
| | name = self._convert_string_type(name.lower()) |
| | return [kv[1] for kv in self._headers if kv[0].lower()==name] |
| |
|
| |
|
| | def get(self,name,default=None): |
| | """Get the first header value for 'name', or return 'default'""" |
| | name = self._convert_string_type(name.lower()) |
| | for k,v in self._headers: |
| | if k.lower()==name: |
| | return v |
| | return default |
| |
|
| |
|
| | def keys(self): |
| | """Return a list of all the header field names. |
| | |
| | These will be sorted in the order they appeared in the original header |
| | list, or were added to this instance, and may contain duplicates. |
| | Any fields deleted and re-inserted are always appended to the header |
| | list. |
| | """ |
| | return [k for k, v in self._headers] |
| |
|
| | def values(self): |
| | """Return a list of all header values. |
| | |
| | These will be sorted in the order they appeared in the original header |
| | list, or were added to this instance, and may contain duplicates. |
| | Any fields deleted and re-inserted are always appended to the header |
| | list. |
| | """ |
| | return [v for k, v in self._headers] |
| |
|
| | def items(self): |
| | """Get all the header fields and values. |
| | |
| | These will be sorted in the order they were in the original header |
| | list, or were added to this instance, and may contain duplicates. |
| | Any fields deleted and re-inserted are always appended to the header |
| | list. |
| | """ |
| | return self._headers[:] |
| |
|
| | def __repr__(self): |
| | return "%s(%r)" % (self.__class__.__name__, self._headers) |
| |
|
| | def __str__(self): |
| | """str() returns the formatted headers, complete with end line, |
| | suitable for direct HTTP transmission.""" |
| | return '\r\n'.join(["%s: %s" % kv for kv in self._headers]+['','']) |
| |
|
| | def __bytes__(self): |
| | return str(self).encode('iso-8859-1') |
| |
|
| | def setdefault(self,name,value): |
| | """Return first matching header value for 'name', or 'value' |
| | |
| | If there is no header named 'name', add a new header with name 'name' |
| | and value 'value'.""" |
| | result = self.get(name) |
| | if result is None: |
| | self._headers.append((self._convert_string_type(name), |
| | self._convert_string_type(value))) |
| | return value |
| | else: |
| | return result |
| |
|
| | def add_header(self, _name, _value, **_params): |
| | """Extended header setting. |
| | |
| | _name is the header field to add. keyword arguments can be used to set |
| | additional parameters for the header field, with underscores converted |
| | to dashes. Normally the parameter will be added as key="value" unless |
| | value is None, in which case only the key will be added. |
| | |
| | Example: |
| | |
| | h.add_header('content-disposition', 'attachment', filename='bud.gif') |
| | |
| | Note that unlike the corresponding 'email.message' method, this does |
| | *not* handle '(charset, language, value)' tuples: all values must be |
| | strings or None. |
| | """ |
| | parts = [] |
| | if _value is not None: |
| | _value = self._convert_string_type(_value) |
| | parts.append(_value) |
| | for k, v in _params.items(): |
| | k = self._convert_string_type(k) |
| | if v is None: |
| | parts.append(k.replace('_', '-')) |
| | else: |
| | v = self._convert_string_type(v) |
| | parts.append(_formatparam(k.replace('_', '-'), v)) |
| | self._headers.append((self._convert_string_type(_name), "; ".join(parts))) |
| |
|
