908 lines
35 KiB
Python
908 lines
35 KiB
Python
# Copyright (C) 2001-2007 Python Software Foundation
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# Author: Barry Warsaw
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# Contact: email-sig@python.org
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"""Basic message object for the email package object model."""
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__all__ = ['Message']
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import re
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import uu
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import base64
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import binascii
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from io import BytesIO, StringIO
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# Intrapackage imports
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from email import utils
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from email import errors
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from email._policybase import compat32
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from email import charset as _charset
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from email._encoded_words import decode_b
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Charset = _charset.Charset
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SEMISPACE = '; '
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# Regular expression that matches `special' characters in parameters, the
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# existence of which force quoting of the parameter value.
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tspecials = re.compile(r'[ \(\)<>@,;:\\"/\[\]\?=]')
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def _splitparam(param):
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# Split header parameters. BAW: this may be too simple. It isn't
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# strictly RFC 2045 (section 5.1) compliant, but it catches most headers
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# found in the wild. We may eventually need a full fledged parser.
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# RDM: we might have a Header here; for now just stringify it.
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a, sep, b = str(param).partition(';')
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if not sep:
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return a.strip(), None
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return a.strip(), b.strip()
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def _formatparam(param, value=None, quote=True):
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"""Convenience function to format and return a key=value pair.
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This will quote the value if needed or if quote is true. If value is a
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three tuple (charset, language, value), it will be encoded according
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to RFC2231 rules. If it contains non-ascii characters it will likewise
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be encoded according to RFC2231 rules, using the utf-8 charset and
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a null language.
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"""
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if value is not None and len(value) > 0:
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# A tuple is used for RFC 2231 encoded parameter values where items
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# are (charset, language, value). charset is a string, not a Charset
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# instance. RFC 2231 encoded values are never quoted, per RFC.
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if isinstance(value, tuple):
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# Encode as per RFC 2231
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param += '*'
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value = utils.encode_rfc2231(value[2], value[0], value[1])
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return '%s=%s' % (param, value)
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else:
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try:
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value.encode('ascii')
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except UnicodeEncodeError:
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param += '*'
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value = utils.encode_rfc2231(value, 'utf-8', '')
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return '%s=%s' % (param, value)
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# BAW: Please check this. I think that if quote is set it should
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# force quoting even if not necessary.
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if quote or tspecials.search(value):
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return '%s="%s"' % (param, utils.quote(value))
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else:
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return '%s=%s' % (param, value)
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else:
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return param
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def _parseparam(s):
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# RDM This might be a Header, so for now stringify it.
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s = ';' + str(s)
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plist = []
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while s[:1] == ';':
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s = s[1:]
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end = s.find(';')
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while end > 0 and (s.count('"', 0, end) - s.count('\\"', 0, end)) % 2:
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end = s.find(';', end + 1)
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if end < 0:
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end = len(s)
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f = s[:end]
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if '=' in f:
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i = f.index('=')
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f = f[:i].strip().lower() + '=' + f[i+1:].strip()
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plist.append(f.strip())
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s = s[end:]
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return plist
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def _unquotevalue(value):
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# This is different than utils.collapse_rfc2231_value() because it doesn't
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# try to convert the value to a unicode. Message.get_param() and
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# Message.get_params() are both currently defined to return the tuple in
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# the face of RFC 2231 parameters.
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if isinstance(value, tuple):
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return value[0], value[1], utils.unquote(value[2])
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else:
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return utils.unquote(value)
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class Message:
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"""Basic message object.
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A message object is defined as something that has a bunch of RFC 2822
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headers and a payload. It may optionally have an envelope header
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(a.k.a. Unix-From or From_ header). If the message is a container (i.e. a
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multipart or a message/rfc822), then the payload is a list of Message
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objects, otherwise it is a string.
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Message objects implement part of the `mapping' interface, which assumes
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there is exactly one occurrence of the header per message. Some headers
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do in fact appear multiple times (e.g. Received) and for those headers,
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you must use the explicit API to set or get all the headers. Not all of
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the mapping methods are implemented.
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"""
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def __init__(self, policy=compat32):
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self.policy = policy
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self._headers = []
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self._unixfrom = None
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self._payload = None
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self._charset = None
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# Defaults for multipart messages
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self.preamble = self.epilogue = None
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self.defects = []
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# Default content type
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self._default_type = 'text/plain'
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def __str__(self):
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"""Return the entire formatted message as a string.
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"""
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return self.as_string()
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def as_string(self, unixfrom=False, maxheaderlen=0, policy=None):
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"""Return the entire formatted message as a string.
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Optional 'unixfrom', when true, means include the Unix From_ envelope
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header. For backward compatibility reasons, if maxheaderlen is
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not specified it defaults to 0, so you must override it explicitly
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if you want a different maxheaderlen. 'policy' is passed to the
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Generator instance used to serialize the mesasge; if it is not
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specified the policy associated with the message instance is used.
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If the message object contains binary data that is not encoded
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according to RFC standards, the non-compliant data will be replaced by
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unicode "unknown character" code points.
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"""
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from email.generator import Generator
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policy = self.policy if policy is None else policy
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fp = StringIO()
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g = Generator(fp,
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mangle_from_=False,
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maxheaderlen=maxheaderlen,
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policy=policy)
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g.flatten(self, unixfrom=unixfrom)
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return fp.getvalue()
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def __bytes__(self):
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"""Return the entire formatted message as a bytes object.
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"""
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return self.as_bytes()
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def as_bytes(self, unixfrom=False, policy=None):
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"""Return the entire formatted message as a bytes object.
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Optional 'unixfrom', when true, means include the Unix From_ envelope
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header. 'policy' is passed to the BytesGenerator instance used to
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serialize the message; if not specified the policy associated with
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the message instance is used.
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"""
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from email.generator import BytesGenerator
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policy = self.policy if policy is None else policy
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fp = BytesIO()
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g = BytesGenerator(fp, mangle_from_=False, policy=policy)
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g.flatten(self, unixfrom=unixfrom)
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return fp.getvalue()
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def is_multipart(self):
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"""Return True if the message consists of multiple parts."""
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return isinstance(self._payload, list)
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#
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# Unix From_ line
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#
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def set_unixfrom(self, unixfrom):
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self._unixfrom = unixfrom
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def get_unixfrom(self):
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return self._unixfrom
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#
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# Payload manipulation.
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#
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def attach(self, payload):
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"""Add the given payload to the current payload.
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The current payload will always be a list of objects after this method
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is called. If you want to set the payload to a scalar object, use
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set_payload() instead.
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"""
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if self._payload is None:
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self._payload = [payload]
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else:
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self._payload.append(payload)
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def get_payload(self, i=None, decode=False):
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"""Return a reference to the payload.
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The payload will either be a list object or a string. If you mutate
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the list object, you modify the message's payload in place. Optional
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i returns that index into the payload.
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Optional decode is a flag indicating whether the payload should be
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decoded or not, according to the Content-Transfer-Encoding header
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(default is False).
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When True and the message is not a multipart, the payload will be
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decoded if this header's value is `quoted-printable' or `base64'. If
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some other encoding is used, or the header is missing, or if the
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payload has bogus data (i.e. bogus base64 or uuencoded data), the
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payload is returned as-is.
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If the message is a multipart and the decode flag is True, then None
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is returned.
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"""
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# Here is the logic table for this code, based on the email5.0.0 code:
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# i decode is_multipart result
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# ------ ------ ------------ ------------------------------
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# None True True None
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# i True True None
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# None False True _payload (a list)
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# i False True _payload element i (a Message)
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# i False False error (not a list)
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# i True False error (not a list)
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# None False False _payload
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# None True False _payload decoded (bytes)
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# Note that Barry planned to factor out the 'decode' case, but that
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# isn't so easy now that we handle the 8 bit data, which needs to be
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# converted in both the decode and non-decode path.
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if self.is_multipart():
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if decode:
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return None
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if i is None:
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return self._payload
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else:
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return self._payload[i]
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# For backward compatibility, Use isinstance and this error message
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# instead of the more logical is_multipart test.
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if i is not None and not isinstance(self._payload, list):
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raise TypeError('Expected list, got %s' % type(self._payload))
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payload = self._payload
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# cte might be a Header, so for now stringify it.
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cte = str(self.get('content-transfer-encoding', '')).lower()
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# payload may be bytes here.
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if isinstance(payload, str):
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if utils._has_surrogates(payload):
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bpayload = payload.encode('ascii', 'surrogateescape')
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if not decode:
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try:
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payload = bpayload.decode(self.get_param('charset', 'ascii'), 'replace')
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except LookupError:
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payload = bpayload.decode('ascii', 'replace')
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elif decode:
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try:
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bpayload = payload.encode('ascii')
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except UnicodeError:
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# This won't happen for RFC compliant messages (messages
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# containing only ASCII codepoints in the unicode input).
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# If it does happen, turn the string into bytes in a way
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# guaranteed not to fail.
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bpayload = payload.encode('raw-unicode-escape')
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if not decode:
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return payload
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if cte == 'quoted-printable':
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return utils._qdecode(bpayload)
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elif cte == 'base64':
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# XXX: this is a bit of a hack; decode_b should probably be factored
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# out somewhere, but I haven't figured out where yet.
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value, defects = decode_b(b''.join(bpayload.splitlines()))
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for defect in defects:
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self.policy.handle_defect(self, defect)
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return value
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elif cte in ('x-uuencode', 'uuencode', 'uue', 'x-uue'):
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in_file = BytesIO(bpayload)
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out_file = BytesIO()
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try:
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uu.decode(in_file, out_file, quiet=True)
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return out_file.getvalue()
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except uu.Error:
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# Some decoding problem
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return bpayload
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if isinstance(payload, str):
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return bpayload
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return payload
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def set_payload(self, payload, charset=None):
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"""Set the payload to the given value.
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Optional charset sets the message's default character set. See
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set_charset() for details.
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"""
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if isinstance(payload, bytes):
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payload = payload.decode('ascii', 'surrogateescape')
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self._payload = payload
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if charset is not None:
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self.set_charset(charset)
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def set_charset(self, charset):
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"""Set the charset of the payload to a given character set.
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charset can be a Charset instance, a string naming a character set, or
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None. If it is a string it will be converted to a Charset instance.
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If charset is None, the charset parameter will be removed from the
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Content-Type field. Anything else will generate a TypeError.
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The message will be assumed to be of type text/* encoded with
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charset.input_charset. It will be converted to charset.output_charset
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and encoded properly, if needed, when generating the plain text
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representation of the message. MIME headers (MIME-Version,
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Content-Type, Content-Transfer-Encoding) will be added as needed.
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"""
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if charset is None:
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self.del_param('charset')
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self._charset = None
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return
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if not isinstance(charset, Charset):
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charset = Charset(charset)
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self._charset = charset
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if 'MIME-Version' not in self:
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self.add_header('MIME-Version', '1.0')
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if 'Content-Type' not in self:
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self.add_header('Content-Type', 'text/plain',
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charset=charset.get_output_charset())
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else:
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self.set_param('charset', charset.get_output_charset())
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if charset != charset.get_output_charset():
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self._payload = charset.body_encode(self._payload)
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if 'Content-Transfer-Encoding' not in self:
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cte = charset.get_body_encoding()
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try:
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cte(self)
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except TypeError:
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self._payload = charset.body_encode(self._payload)
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self.add_header('Content-Transfer-Encoding', cte)
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def get_charset(self):
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"""Return the Charset instance associated with the message's payload.
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"""
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return self._charset
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#
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# MAPPING INTERFACE (partial)
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#
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def __len__(self):
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"""Return the total number of headers, including duplicates."""
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return len(self._headers)
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def __getitem__(self, name):
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"""Get a header value.
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Return None if the header is missing instead of raising an exception.
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Note that if the header appeared multiple times, exactly which
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occurrence gets returned is undefined. Use get_all() to get all
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the values matching a header field name.
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"""
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return self.get(name)
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def __setitem__(self, name, val):
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"""Set the value of a header.
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Note: this does not overwrite an existing header with the same field
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name. Use __delitem__() first to delete any existing headers.
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"""
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max_count = self.policy.header_max_count(name)
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if max_count:
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lname = name.lower()
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found = 0
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for k, v in self._headers:
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if k.lower() == lname:
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found += 1
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if found >= max_count:
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raise ValueError("There may be at most {} {} headers "
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"in a message".format(max_count, name))
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self._headers.append(self.policy.header_store_parse(name, val))
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def __delitem__(self, name):
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"""Delete all occurrences of a header, if present.
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Does not raise an exception if the header is missing.
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"""
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name = name.lower()
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newheaders = []
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for k, v in self._headers:
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if k.lower() != name:
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newheaders.append((k, v))
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self._headers = newheaders
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def __contains__(self, name):
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return name.lower() in [k.lower() for k, v in self._headers]
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def __iter__(self):
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for field, value in self._headers:
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yield field
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def keys(self):
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"""Return a list of all the message's header field names.
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These will be sorted in the order they appeared in the original
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message, or were added to the message, and may contain duplicates.
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Any fields deleted and re-inserted are always appended to the header
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list.
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"""
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return [k for k, v in self._headers]
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def values(self):
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"""Return a list of all the message's header values.
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These will be sorted in the order they appeared in the original
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message, or were added to the message, and may contain duplicates.
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Any fields deleted and re-inserted are always appended to the header
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list.
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"""
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return [self.policy.header_fetch_parse(k, v)
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for k, v in self._headers]
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def items(self):
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"""Get all the message's header fields and values.
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These will be sorted in the order they appeared in the original
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message, or were added to the message, and may contain duplicates.
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Any fields deleted and re-inserted are always appended to the header
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list.
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"""
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return [(k, self.policy.header_fetch_parse(k, v))
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for k, v in self._headers]
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def get(self, name, failobj=None):
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"""Get a header value.
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Like __getitem__() but return failobj instead of None when the field
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is missing.
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"""
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name = name.lower()
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for k, v in self._headers:
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if k.lower() == name:
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return self.policy.header_fetch_parse(k, v)
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return failobj
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#
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# "Internal" methods (public API, but only intended for use by a parser
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# or generator, not normal application code.
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#
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def set_raw(self, name, value):
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"""Store name and value in the model without modification.
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This is an "internal" API, intended only for use by a parser.
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"""
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self._headers.append((name, value))
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def raw_items(self):
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"""Return the (name, value) header pairs without modification.
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This is an "internal" API, intended only for use by a generator.
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"""
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return iter(self._headers.copy())
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#
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# Additional useful stuff
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#
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def get_all(self, name, failobj=None):
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"""Return a list of all the values for the named field.
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These will be sorted in the order they appeared in the original
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message, and may contain duplicates. Any fields deleted and
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re-inserted are always appended to the header list.
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If no such fields exist, failobj is returned (defaults to None).
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"""
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values = []
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name = name.lower()
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for k, v in self._headers:
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if k.lower() == name:
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values.append(self.policy.header_fetch_parse(k, v))
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if not values:
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return failobj
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return values
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def add_header(self, _name, _value, **_params):
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"""Extended header setting.
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name is the header field to add. keyword arguments can be used to set
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additional parameters for the header field, with underscores converted
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to dashes. Normally the parameter will be added as key="value" unless
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value is None, in which case only the key will be added. If a
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parameter value contains non-ASCII characters it can be specified as a
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three-tuple of (charset, language, value), in which case it will be
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encoded according to RFC2231 rules. Otherwise it will be encoded using
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the utf-8 charset and a language of ''.
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Examples:
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msg.add_header('content-disposition', 'attachment', filename='bud.gif')
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msg.add_header('content-disposition', 'attachment',
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filename=('utf-8', '', Fußballer.ppt'))
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msg.add_header('content-disposition', 'attachment',
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filename='Fußballer.ppt'))
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"""
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parts = []
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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[_name] = SEMISPACE.join(parts)
|
||
|
||
def replace_header(self, _name, _value):
|
||
"""Replace a header.
|
||
|
||
Replace the first matching header found in the message, retaining
|
||
header order and case. If no matching header was found, a KeyError is
|
||
raised.
|
||
"""
|
||
_name = _name.lower()
|
||
for i, (k, v) in zip(range(len(self._headers)), self._headers):
|
||
if k.lower() == _name:
|
||
self._headers[i] = self.policy.header_store_parse(k, _value)
|
||
break
|
||
else:
|
||
raise KeyError(_name)
|
||
|
||
#
|
||
# Use these three methods instead of the three above.
|
||
#
|
||
|
||
def get_content_type(self):
|
||
"""Return the message's content type.
|
||
|
||
The returned string is coerced to lower case of the form
|
||
`maintype/subtype'. If there was no Content-Type header in the
|
||
message, the default type as given by get_default_type() will be
|
||
returned. Since according to RFC 2045, messages always have a default
|
||
type this will always return a value.
|
||
|
||
RFC 2045 defines a message's default type to be text/plain unless it
|
||
appears inside a multipart/digest container, in which case it would be
|
||
message/rfc822.
|
||
"""
|
||
missing = object()
|
||
value = self.get('content-type', missing)
|
||
if value is missing:
|
||
# This should have no parameters
|
||
return self.get_default_type()
|
||
ctype = _splitparam(value)[0].lower()
|
||
# RFC 2045, section 5.2 says if its invalid, use text/plain
|
||
if ctype.count('/') != 1:
|
||
return 'text/plain'
|
||
return ctype
|
||
|
||
def get_content_maintype(self):
|
||
"""Return the message's main content type.
|
||
|
||
This is the `maintype' part of the string returned by
|
||
get_content_type().
|
||
"""
|
||
ctype = self.get_content_type()
|
||
return ctype.split('/')[0]
|
||
|
||
def get_content_subtype(self):
|
||
"""Returns the message's sub-content type.
|
||
|
||
This is the `subtype' part of the string returned by
|
||
get_content_type().
|
||
"""
|
||
ctype = self.get_content_type()
|
||
return ctype.split('/')[1]
|
||
|
||
def get_default_type(self):
|
||
"""Return the `default' content type.
|
||
|
||
Most messages have a default content type of text/plain, except for
|
||
messages that are subparts of multipart/digest containers. Such
|
||
subparts have a default content type of message/rfc822.
|
||
"""
|
||
return self._default_type
|
||
|
||
def set_default_type(self, ctype):
|
||
"""Set the `default' content type.
|
||
|
||
ctype should be either "text/plain" or "message/rfc822", although this
|
||
is not enforced. The default content type is not stored in the
|
||
Content-Type header.
|
||
"""
|
||
self._default_type = ctype
|
||
|
||
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 = object()
|
||
value = self.get(header, missing)
|
||
if value is missing:
|
||
return failobj
|
||
params = []
|
||
for p in _parseparam(value):
|
||
try:
|
||
name, val = p.split('=', 1)
|
||
name = name.strip()
|
||
val = val.strip()
|
||
except ValueError:
|
||
# Must have been a bare attribute
|
||
name = p.strip()
|
||
val = ''
|
||
params.append((name, val))
|
||
params = utils.decode_params(params)
|
||
return params
|
||
|
||
def get_params(self, failobj=None, header='content-type', unquote=True):
|
||
"""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 as
|
||
described in the get_param() method.
|
||
|
||
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. If unquote is True, the value is unquoted.
|
||
"""
|
||
missing = object()
|
||
params = self._get_params_preserve(missing, header)
|
||
if params is missing:
|
||
return failobj
|
||
if unquote:
|
||
return [(k, _unquotevalue(v)) for k, v in params]
|
||
else:
|
||
return params
|
||
|
||
def get_param(self, param, failobj=None, header='content-type',
|
||
unquote=True):
|
||
"""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, or the Content-Type header has no such parameter. Optional
|
||
header is the header to search instead of Content-Type.
|
||
|
||
Parameter keys are always compared case insensitively. The return
|
||
value can either be a string, or a 3-tuple if the parameter was RFC
|
||
2231 encoded. When it's a 3-tuple, the elements of the value are of
|
||
the form (CHARSET, LANGUAGE, VALUE). Note that both CHARSET and
|
||
LANGUAGE can be None, in which case you should consider VALUE to be
|
||
encoded in the us-ascii charset. You can usually ignore LANGUAGE.
|
||
The parameter value (either the returned string, or the VALUE item in
|
||
the 3-tuple) is always unquoted, unless unquote is set to False.
|
||
|
||
If your application doesn't care whether the parameter was RFC 2231
|
||
encoded, it can turn the return value into a string as follows:
|
||
|
||
param = msg.get_param('foo')
|
||
param = email.utils.collapse_rfc2231_value(rawparam)
|
||
|
||
"""
|
||
if header not in self:
|
||
return failobj
|
||
for k, v in self._get_params_preserve(failobj, header):
|
||
if k.lower() == param.lower():
|
||
if unquote:
|
||
return _unquotevalue(v)
|
||
else:
|
||
return v
|
||
return failobj
|
||
|
||
def set_param(self, param, value, header='Content-Type', requote=True,
|
||
charset=None, language=''):
|
||
"""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 for 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 necessary unless requote is False.
|
||
|
||
If charset is specified, the parameter will be encoded according to RFC
|
||
2231. Optional language specifies the RFC 2231 language, defaulting
|
||
to the empty string. Both charset and language should be strings.
|
||
"""
|
||
if not isinstance(value, tuple) and charset:
|
||
value = (charset, language, value)
|
||
|
||
if header not in self 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=True):
|
||
"""Remove the given parameter completely from the Content-Type header.
|
||
|
||
The header will be re-written in place without the parameter or its
|
||
value. All values will be quoted as necessary unless requote is
|
||
False. Optional header specifies an alternative to the Content-Type
|
||
header.
|
||
"""
|
||
if header not in self:
|
||
return
|
||
new_ctype = ''
|
||
for p, v in self.get_params(header=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=True):
|
||
"""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 alternative 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 header not in self:
|
||
self[header] = type
|
||
return
|
||
params = self.get_params(header=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. If that header is missing
|
||
the `filename' parameter, this method falls back to looking for the
|
||
`name' parameter.
|
||
"""
|
||
missing = object()
|
||
filename = self.get_param('filename', missing, 'content-disposition')
|
||
if filename is missing:
|
||
filename = self.get_param('name', missing, 'content-type')
|
||
if filename is missing:
|
||
return failobj
|
||
return utils.collapse_rfc2231_value(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 = object()
|
||
boundary = self.get_param('boundary', missing)
|
||
if boundary is missing:
|
||
return failobj
|
||
# RFC 2046 says that boundaries may begin but not end in w/s
|
||
return utils.collapse_rfc2231_value(boundary).rstrip()
|
||
|
||
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 = object()
|
||
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 = False
|
||
for pk, pv in params:
|
||
if pk.lower() == 'boundary':
|
||
newparams.append(('boundary', '"%s"' % boundary))
|
||
foundp = True
|
||
else:
|
||
newparams.append((pk, pv))
|
||
if not foundp:
|
||
# The original Content-Type header had no boundary attribute.
|
||
# Tack one on 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))
|
||
val = SEMISPACE.join(parts)
|
||
newheaders.append(self.policy.header_store_parse(h, val))
|
||
|
||
else:
|
||
newheaders.append((h, v))
|
||
self._headers = newheaders
|
||
|
||
def get_content_charset(self, failobj=None):
|
||
"""Return the charset parameter of the Content-Type header.
|
||
|
||
The returned string is always coerced to lower case. If there is no
|
||
Content-Type header, or if that header has no charset parameter,
|
||
failobj is returned.
|
||
"""
|
||
missing = object()
|
||
charset = self.get_param('charset', missing)
|
||
if charset is missing:
|
||
return failobj
|
||
if isinstance(charset, tuple):
|
||
# RFC 2231 encoded, so decode it, and it better end up as ascii.
|
||
pcharset = charset[0] or 'us-ascii'
|
||
try:
|
||
# LookupError will be raised if the charset isn't known to
|
||
# Python. UnicodeError will be raised if the encoded text
|
||
# contains a character not in the charset.
|
||
as_bytes = charset[2].encode('raw-unicode-escape')
|
||
charset = str(as_bytes, pcharset)
|
||
except (LookupError, UnicodeError):
|
||
charset = charset[2]
|
||
# charset characters must be in us-ascii range
|
||
try:
|
||
charset.encode('us-ascii')
|
||
except UnicodeError:
|
||
return failobj
|
||
# RFC 2046, $4.1.2 says charsets are not case sensitive
|
||
return charset.lower()
|
||
|
||
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_content_charset(failobj) for part in self.walk()]
|
||
|
||
# I.e. def walk(self): ...
|
||
from email.iterators import walk
|