| # Copyright (C) 2001,2002 Python Software Foundation |
| # Author: barry@zope.com (Barry Warsaw) |
| |
| """Basic message object for the email package object model. |
| """ |
| |
| import re |
| import warnings |
| from cStringIO import StringIO |
| from types import ListType, StringType |
| |
| # Intrapackage imports |
| import Errors |
| import Utils |
| import Charset |
| |
| SEMISPACE = '; ' |
| |
| # Regular expression used to split header parameters. BAW: this may be too |
| # simple. It isn't strictly RFC 2045 (section 5.1) compliant, but it catches |
| # most headers found in the wild. We may eventually need a full fledged |
| # parser eventually. |
| paramre = re.compile(r'\s*;\s*') |
| # Regular expression that matches `special' characters in parameters, the |
| # existance of which force quoting of the parameter value. |
| tspecials = re.compile(r'[ \(\)<>@,;:\\"/\[\]\?=]') |
| |
| |
| |
| # Helper function |
| def _formatparam(param, value=None, quote=1): |
| """Convenience function to format and return a key=value pair. |
| |
| Will quote the value if needed or if quote is true. |
| """ |
| if value is not None and len(value) > 0: |
| # BAW: Please check this. I think that if quote is set it should |
| # force quoting even if not necessary. |
| if quote or tspecials.search(value): |
| return '%s="%s"' % (param, Utils.quote(value)) |
| else: |
| return '%s=%s' % (param, value) |
| else: |
| return param |
| |
| |
| |
| class Message: |
| """Basic message object for use inside the object tree. |
| |
| A message object is defined as something that has a bunch of RFC 2822 |
| headers and a payload. If the body of the message is a multipart, then |
| the payload is a list of Messages, otherwise it is a string. |
| |
| These objects implement part of the `mapping' interface, which assumes |
| there is exactly one occurrance of the header per message. Some headers |
| do in fact appear multiple times (e.g. Received:) and for those headers, |
| you must use the explicit API to set or get all the headers. Not all of |
| the mapping methods are implemented. |
| |
| """ |
| def __init__(self): |
| self._headers = [] |
| self._unixfrom = None |
| self._payload = None |
| self._charset = None |
| # Defaults for multipart messages |
| self.preamble = self.epilogue = None |
| |
| def __str__(self): |
| """Return the entire formatted message as a string. |
| This includes the headers, body, and `unixfrom' line. |
| """ |
| return self.as_string(unixfrom=1) |
| |
| def as_string(self, unixfrom=0): |
| """Return the entire formatted message as a string. |
| Optional `unixfrom' when true, means include the Unix From_ envelope |
| header. |
| """ |
| from Generator import Generator |
| fp = StringIO() |
| g = Generator(fp) |
| g(self, unixfrom=unixfrom) |
| return fp.getvalue() |
| |
| def is_multipart(self): |
| """Return true if the message consists of multiple parts.""" |
| if type(self._payload) is ListType: |
| return 1 |
| return 0 |
| |
| # |
| # Unix From_ line |
| # |
| def set_unixfrom(self, unixfrom): |
| self._unixfrom = unixfrom |
| |
| def get_unixfrom(self): |
| return self._unixfrom |
| |
| # |
| # Payload manipulation. |
| # |
| def add_payload(self, payload): |
| """Add the given payload to the current payload. |
| |
| If the current payload is empty, then the current payload will be made |
| a scalar, set to the given value. |
| """ |
| warnings.warn('add_payload() is deprecated, use attach() instead.', |
| DeprecationWarning, 2) |
| if self._payload is None: |
| self._payload = payload |
| elif type(self._payload) is ListType: |
| self._payload.append(payload) |
| elif self.get_main_type() not in (None, 'multipart'): |
| raise Errors.MultipartConversionError( |
| 'Message main Content-Type: must be "multipart" or missing') |
| else: |
| self._payload = [self._payload, payload] |
| |
| def attach(self, payload): |
| """Add the given payload to the current payload. |
| |
| The current payload will always be a list of objects after this method |
| is called. If you want to set the payload to a scalar object |
| (e.g. because you're attaching a message/rfc822 subpart), use |
| set_payload() instead. |
| """ |
| if self._payload is None: |
| self._payload = [payload] |
| else: |
| self._payload.append(payload) |
| |
| def get_payload(self, i=None, decode=0): |
| """Return the current payload exactly as is. |
| |
| Optional i returns that index into the payload. |
| |
| Optional decode is a flag indicating whether the payload should be |
| decoded or not, according to the Content-Transfer-Encoding: header. |
| When true and the message is not a multipart, the payload will be |
| decoded if this header's value is `quoted-printable' or `base64'. If |
| some other encoding is used, or the header is missing, the payload is |
| returned as-is (undecoded). If the message is a multipart and the |
| decode flag is true, then None is returned. |
| """ |
| if i is None: |
| payload = self._payload |
| elif type(self._payload) is not ListType: |
| raise TypeError, i |
| else: |
| payload = self._payload[i] |
| if decode: |
| if self.is_multipart(): |
| return None |
| cte = self.get('content-transfer-encoding', '') |
| if cte.lower() == 'quoted-printable': |
| return Utils._qdecode(payload) |
| elif cte.lower() == 'base64': |
| return Utils._bdecode(payload) |
| # Everything else, including encodings with 8bit or 7bit are returned |
| # unchanged. |
| return payload |
| |
| |
| def set_payload(self, payload, charset=None): |
| """Set the payload to the given value. |
| |
| Optionally set the charset, which must be a Charset instance.""" |
| self._payload = payload |
| if charset is not None: |
| self.set_charset(charset) |
| |
| def set_charset(self, charset): |
| """Set the charset of the payload to a given character set. |
| |
| charset can be a string or a Charset object. If it is a string, it |
| will be converted to a Charset object by calling Charset's |
| constructor. If charset is None, the charset parameter will be |
| removed from the Content-Type: field. Anything else will generate a |
| TypeError. |
| |
| The message will be assumed to be a text message encoded with |
| charset.input_charset. It will be converted to charset.output_charset |
| and encoded properly, if needed, when generating the plain text |
| representation of the message. MIME headers (MIME-Version, |
| Content-Type, Content-Transfer-Encoding) will be added as needed. |
| """ |
| if charset is None: |
| self.del_param('charset') |
| self._charset = None |
| return |
| if isinstance(charset, StringType): |
| charset = Charset.Charset(charset) |
| if not isinstance(charset, Charset.Charset): |
| raise TypeError, charset |
| # BAW: should we accept strings that can serve as arguments to the |
| # Charset constructor? |
| self._charset = charset |
| if not self.has_key('MIME-Version'): |
| self.add_header('MIME-Version', '1.0') |
| if not self.has_key('Content-Type'): |
| self.add_header('Content-Type', 'text/plain', |
| charset=charset.get_output_charset()) |
| else: |
| self.set_param('charset', charset.get_output_charset()) |
| if not self.has_key('Content-Transfer-Encoding'): |
| cte = charset.get_body_encoding() |
| if callable(cte): |
| cte(self) |
| else: |
| self.add_header('Content-Transfer-Encoding', cte) |
| |
| def get_charset(self): |
| """Return the Charset object associated with the message's payload.""" |
| return self._charset |
| |
| # |
| # MAPPING INTERFACE (partial) |
| # |
| def __len__(self): |
| """Return the total number of headers, including duplicates.""" |
| return len(self._headers) |
| |
| def __getitem__(self, name): |
| """Get a header value. |
| |
| Return None if the header is missing instead of raising an exception. |
| |
| Note that if the header appeared multiple times, exactly which |
| occurrance gets returned is undefined. Use getall() to get all |
| the values matching a header field name. |
| """ |
| return self.get(name) |
| |
| def __setitem__(self, name, val): |
| """Set the value of a header. |
| |
| Note: this does not overwrite an existing header with the same field |
| name. Use __delitem__() first to delete any existing headers. |
| """ |
| self._headers.append((name, val)) |
| |
| def __delitem__(self, name): |
| """Delete all occurrences of a header, if present. |
| |
| Does not raise an exception if the header is missing. |
| """ |
| name = name.lower() |
| newheaders = [] |
| for k, v in self._headers: |
| if k.lower() <> name: |
| newheaders.append((k, v)) |
| self._headers = newheaders |
| |
| def __contains__(self, key): |
| return key.lower() in [k.lower() for k, v in self._headers] |
| |
| def has_key(self, name): |
| """Return true if the message contains the header.""" |
| missing = [] |
| return self.get(name, missing) is not missing |
| |
| def keys(self): |
| """Return a list of all the message's header field names. |
| |
| These will be sorted in the order they appeared in the original |
| message, 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 the message's header values. |
| |
| These will be sorted in the order they appeared in the original |
| message, 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 message's header fields and values. |
| |
| These will be sorted in the order they appeared in the original |
| message, and may contain duplicates. Any fields deleted and |
| re-inserted are always appended to the header list. |
| """ |
| return self._headers[:] |
| |
| def get(self, name, failobj=None): |
| """Get a header value. |
| |
| Like __getitem__() but return failobj instead of None when the field |
| is missing. |
| """ |
| name = name.lower() |
| for k, v in self._headers: |
| if k.lower() == name: |
| return v |
| return failobj |
| |
| # |
| # Additional useful stuff |
| # |
| |
| def get_all(self, name, failobj=None): |
| """Return a list of all the values for the named field. |
| |
| These will be sorted in the order they appeared in the original |
| message, and may contain duplicates. Any fields deleted and |
| re-inserted are always appended to the header list. |
| |
| If no such fields exist, failobj is returned (defaults to None). |
| """ |
| values = [] |
| name = name.lower() |
| for k, v in self._headers: |
| if k.lower() == name: |
| values.append(v) |
| if not values: |
| return failobj |
| return values |
| |
| 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: |
| |
| msg.add_header('content-disposition', 'attachment', filename='bud.gif') |
| |
| """ |
| parts = [] |
| for k, v in _params.items(): |
| if v is None: |
| parts.append(k.replace('_', '-')) |
| else: |
| parts.append(_formatparam(k.replace('_', '-'), v)) |
| if _value is not None: |
| parts.insert(0, _value) |
| self._headers.append((_name, SEMISPACE.join(parts))) |
| |
| def get_type(self, failobj=None): |
| """Returns the message's content type. |
| |
| The returned string is coerced to lowercase and returned as a single |
| string of the form `maintype/subtype'. If there was no Content-Type: |
| header in the message, failobj is returned (defaults to None). |
| """ |
| missing = [] |
| value = self.get('content-type', missing) |
| if value is missing: |
| return failobj |
| return paramre.split(value)[0].lower() |
| |
| def get_main_type(self, failobj=None): |
| """Return the message's main content type if present.""" |
| missing = [] |
| ctype = self.get_type(missing) |
| if ctype is missing: |
| return failobj |
| parts = ctype.split('/') |
| if len(parts) > 0: |
| return ctype.split('/')[0] |
| return failobj |
| |
| def get_subtype(self, failobj=None): |
| """Return the message's content subtype if present.""" |
| missing = [] |
| ctype = self.get_type(missing) |
| if ctype is missing: |
| return failobj |
| parts = ctype.split('/') |
| if len(parts) > 1: |
| return ctype.split('/')[1] |
| return failobj |
| |
| def _get_params_preserve(self, failobj, header): |
| # Like get_params() but preserves the quoting of values. BAW: |
| # should this be part of the public interface? |
| missing = [] |
| value = self.get(header, missing) |
| if value is missing: |
| return failobj |
| params = [] |
| for p in paramre.split(value): |
| try: |
| name, val = p.split('=', 1) |
| name = name.rstrip() |
| val = val.lstrip() |
| except ValueError: |
| # Must have been a bare attribute |
| name = p |
| val = '' |
| params.append((name, val)) |
| return params |
| |
| def get_params(self, failobj=None, header='content-type', unquote=1): |
| """Return the message's Content-Type: parameters, as a list. |
| |
| The elements of the returned list are 2-tuples of key/value pairs, as |
| split on the `=' sign. The left hand side of the `=' is the key, |
| while the right hand side is the value. If there is no `=' sign in |
| the parameter the value is the empty string. The value is always |
| unquoted, unless unquote is set to a false value. |
| |
| Optional failobj is the object to return if there is no Content-Type: |
| header. Optional header is the header to search instead of |
| Content-Type:. |
| """ |
| missing = [] |
| params = self._get_params_preserve(missing, header) |
| if params is missing: |
| return failobj |
| if unquote: |
| return [(k, Utils.unquote(v)) for k, v in params] |
| else: |
| return params |
| |
| def get_param(self, param, failobj=None, header='content-type', unquote=1): |
| """Return the parameter value if found in the Content-Type: header. |
| |
| Optional failobj is the object to return if there is no Content-Type: |
| header. Optional header is the header to search instead of |
| Content-Type: |
| |
| Parameter keys are always compared case insensitively. Values are |
| always unquoted, unless unquote is set to a false value. |
| """ |
| if not self.has_key(header): |
| return failobj |
| for k, v in self._get_params_preserve(failobj, header): |
| if k.lower() == param.lower(): |
| if unquote: |
| return Utils.unquote(v) |
| else: |
| return v |
| return failobj |
| |
| def set_param(self, param, value, header='Content-Type', requote=1): |
| """Set a parameter in the Content-Type: header. |
| |
| If the parameter already exists in the header, its value will be |
| replaced with the new value. |
| |
| If header is Content-Type: and has not yet been defined in this |
| message, it will be set to "text/plain" and the new parameter and |
| value will be appended, as per RFC 2045. |
| |
| An alternate header can specified in the header argument, and |
| all parameters will be quoted as appropriate unless requote is |
| set to a false value. |
| """ |
| if not self.has_key(header) and header.lower() == 'content-type': |
| ctype = 'text/plain' |
| else: |
| ctype = self.get(header) |
| if not self.get_param(param, header=header): |
| if not ctype: |
| ctype = _formatparam(param, value, requote) |
| else: |
| ctype = SEMISPACE.join( |
| [ctype, _formatparam(param, value, requote)]) |
| else: |
| ctype = '' |
| for old_param, old_value in self.get_params(header=header, |
| unquote=requote): |
| append_param = '' |
| if old_param.lower() == param.lower(): |
| append_param = _formatparam(param, value, requote) |
| else: |
| append_param = _formatparam(old_param, old_value, requote) |
| if not ctype: |
| ctype = append_param |
| else: |
| ctype = SEMISPACE.join([ctype, append_param]) |
| if ctype <> self.get(header): |
| del self[header] |
| self[header] = ctype |
| |
| def del_param(self, param, header='content-type', requote=1): |
| """Remove the given parameter completely from the Content-Type header. |
| |
| The header will be re-written in place without param or its value. |
| All values will be quoted as appropriate unless requote is set to a |
| false value. |
| """ |
| if not self.has_key(header): |
| return |
| new_ctype = '' |
| for p, v in self.get_params(header, unquote=requote): |
| if p.lower() <> param.lower(): |
| if not new_ctype: |
| new_ctype = _formatparam(p, v, requote) |
| else: |
| new_ctype = SEMISPACE.join([new_ctype, |
| _formatparam(p, v, requote)]) |
| if new_ctype <> self.get(header): |
| del self[header] |
| self[header] = new_ctype |
| |
| def set_type(self, type, header='Content-Type', requote=1): |
| """Set the main type and subtype for the Content-Type: header. |
| |
| type must be a string in the form "maintype/subtype", otherwise a |
| ValueError is raised. |
| |
| This method replaces the Content-Type: header, keeping all the |
| parameters in place. If requote is false, this leaves the existing |
| header's quoting as is. Otherwise, the parameters will be quoted (the |
| default). |
| |
| An alternate header can be specified in the header argument. When the |
| Content-Type: header is set, we'll always also add a MIME-Version: |
| header. |
| """ |
| # BAW: should we be strict? |
| if not type.count('/') == 1: |
| raise ValueError |
| # Set the Content-Type: you get a MIME-Version: |
| if header.lower() == 'content-type': |
| del self['mime-version'] |
| self['MIME-Version'] = '1.0' |
| if not self.has_key(header): |
| self[header] = type |
| return |
| params = self.get_params(header, unquote=requote) |
| del self[header] |
| self[header] = type |
| # Skip the first param; it's the old type. |
| for p, v in params[1:]: |
| self.set_param(p, v, header, requote) |
| |
| def get_filename(self, failobj=None): |
| """Return the filename associated with the payload if present. |
| |
| The filename is extracted from the Content-Disposition: header's |
| `filename' parameter, and it is unquoted. |
| """ |
| missing = [] |
| filename = self.get_param('filename', missing, 'content-disposition') |
| if filename is missing: |
| return failobj |
| return Utils.unquote(filename.strip()) |
| |
| def get_boundary(self, failobj=None): |
| """Return the boundary associated with the payload if present. |
| |
| The boundary is extracted from the Content-Type: header's `boundary' |
| parameter, and it is unquoted. |
| """ |
| missing = [] |
| boundary = self.get_param('boundary', missing) |
| if boundary is missing: |
| return failobj |
| return Utils.unquote(boundary.strip()) |
| |
| def set_boundary(self, boundary): |
| """Set the boundary parameter in Content-Type: to 'boundary'. |
| |
| This is subtly different than deleting the Content-Type: header and |
| adding a new one with a new boundary parameter via add_header(). The |
| main difference is that using the set_boundary() method preserves the |
| order of the Content-Type: header in the original message. |
| |
| HeaderParseError is raised if the message has no Content-Type: header. |
| """ |
| missing = [] |
| params = self._get_params_preserve(missing, 'content-type') |
| if params is missing: |
| # There was no Content-Type: header, and we don't know what type |
| # to set it to, so raise an exception. |
| raise Errors.HeaderParseError, 'No Content-Type: header found' |
| newparams = [] |
| foundp = 0 |
| for pk, pv in params: |
| if pk.lower() == 'boundary': |
| newparams.append(('boundary', '"%s"' % boundary)) |
| foundp = 1 |
| else: |
| newparams.append((pk, pv)) |
| if not foundp: |
| # The original Content-Type: header had no boundary attribute. |
| # Tack one one the end. BAW: should we raise an exception |
| # instead??? |
| newparams.append(('boundary', '"%s"' % boundary)) |
| # Replace the existing Content-Type: header with the new value |
| newheaders = [] |
| for h, v in self._headers: |
| if h.lower() == 'content-type': |
| parts = [] |
| for k, v in newparams: |
| if v == '': |
| parts.append(k) |
| else: |
| parts.append('%s=%s' % (k, v)) |
| newheaders.append((h, SEMISPACE.join(parts))) |
| |
| else: |
| newheaders.append((h, v)) |
| self._headers = newheaders |
| |
| def walk(self): |
| """Walk over the message tree, yielding each subpart. |
| |
| The walk is performed in depth-first order. This method is a |
| generator. |
| """ |
| yield self |
| if self.is_multipart(): |
| for subpart in self.get_payload(): |
| for subsubpart in subpart.walk(): |
| yield subsubpart |
| |
| def get_charsets(self, failobj=None): |
| """Return a list containing the charset(s) used in this message. |
| |
| The returned list of items describes the Content-Type: headers' |
| charset parameter for this message and all the subparts in its |
| payload. |
| |
| Each item will either be a string (the value of the charset parameter |
| in the Content-Type: header of that part) or the value of the |
| 'failobj' parameter (defaults to None), if the part does not have a |
| main MIME type of "text", or the charset is not defined. |
| |
| The list will contain one string for each part of the message, plus |
| one for the container message (i.e. self), so that a non-multipart |
| message will still return a list of length 1. |
| """ |
| return [part.get_param('charset', failobj) for part in self.walk()] |