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Diffstat (limited to 'src/leap/bitmask/mail/imap/messages.py')
| -rw-r--r-- | src/leap/bitmask/mail/imap/messages.py | 254 |
1 files changed, 254 insertions, 0 deletions
diff --git a/src/leap/bitmask/mail/imap/messages.py b/src/leap/bitmask/mail/imap/messages.py new file mode 100644 index 0000000..d1c7b93 --- /dev/null +++ b/src/leap/bitmask/mail/imap/messages.py @@ -0,0 +1,254 @@ +# -*- coding: utf-8 -*- +# imap/messages.py +# Copyright (C) 2013-2015 LEAP +# +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation, either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. +""" +IMAPMessage implementation. +""" +import logging +from twisted.mail import imap4 +from twisted.internet import defer +from zope.interface import implements + +from leap.mail.utils import find_charset, CaseInsensitiveDict + + +logger = logging.getLogger(__name__) + +# TODO +# [ ] Add ref to incoming message during add_msg. + + +class IMAPMessage(object): + """ + The main representation of a message as seen by the IMAP Server. + This class implements the semantics specific to IMAP specification. + """ + implements(imap4.IMessage) + + def __init__(self, message, prefetch_body=True, + store=None, d=defer.Deferred()): + """ + Get an IMAPMessage. A mail.Message is needed, since many of the methods + are proxied to that object. + + + If you do not need to prefetch the body of the message, you can set + `prefetch_body` to False, but the current imap server implementation + expect the getBodyFile method to return inmediately. + + When the prefetch_body option is used, a deferred is also expected as a + parameter, and this will fire when the deferred initialization has + taken place, with this instance of IMAPMessage as a parameter. + + :param message: the abstract message + :type message: mail.Message + :param prefetch_body: Whether to prefetch the content doc for the body. + :type prefetch_body: bool + :param store: an instance of soledad, or anything that behaves like it. + :param d: an optional deferred, that will be fired with the instance of + the IMAPMessage being initialized + :type d: defer.Deferred + """ + # TODO substitute the use of the deferred initialization by a factory + # function, maybe. + + self.message = message + self.__body_fd = None + self.store = store + if prefetch_body: + gotbody = self.__prefetch_body_file() + gotbody.addCallback(lambda _: d.callback(self)) + + # IMessage implementation + + def getUID(self): + """ + Retrieve the unique identifier associated with this Message. + + :return: uid for this message + :rtype: int + """ + return self.message.get_uid() + + def getFlags(self): + """ + Retrieve the flags associated with this Message. + + :return: The flags, represented as strings + :rtype: tuple + """ + return self.message.get_flags() + + def getInternalDate(self): + """ + Retrieve the date internally associated with this message + + According to the spec, this is NOT the date and time in the + RFC-822 header, but rather a date and time that reflects when the + message was received. + + * In SMTP, date and time of final delivery. + * In COPY, internal date/time of the source message. + * In APPEND, date/time specified. + + :return: An RFC822-formatted date string. + :rtype: str + """ + return self.message.get_internal_date() + + # + # IMessagePart + # + + def getBodyFile(self, store=None): + """ + Retrieve a file object containing only the body of this message. + + :return: file-like object opened for reading + :rtype: a deferred that will fire with a StringIO object. + """ + if self.__body_fd is not None: + fd = self.__body_fd + fd.seek(0) + return fd + + if store is None: + store = self.store + return self.message.get_body_file(store) + + def getSize(self): + """ + Return the total size, in octets, of this message. + + :return: size of the message, in octets + :rtype: int + """ + return self.message.get_size() + + def getHeaders(self, negate, *names): + """ + Retrieve a group of message headers. + + :param names: The names of the headers to retrieve or omit. + :type names: tuple of str + + :param negate: If True, indicates that the headers listed in names + should be omitted from the return value, rather + than included. + :type negate: bool + + :return: A mapping of header field names to header field values + :rtype: dict + """ + headers = self.message.get_headers() + return _format_headers(headers, negate, *names) + + def isMultipart(self): + """ + Return True if this message is multipart. + """ + return self.message.is_multipart() + + def getSubPart(self, part): + """ + Retrieve a MIME submessage + + :type part: C{int} + :param part: The number of the part to retrieve, indexed from 0. + :raise IndexError: Raised if the specified part does not exist. + :raise TypeError: Raised if this message is not multipart. + :rtype: Any object implementing C{IMessagePart}. + :return: The specified sub-part. + """ + subpart = self.message.get_subpart(part + 1) + return IMAPMessagePart(subpart) + + def __prefetch_body_file(self): + def assign_body_fd(fd): + self.__body_fd = fd + return fd + d = self.getBodyFile() + d.addCallback(assign_body_fd) + return d + + +class IMAPMessagePart(object): + + def __init__(self, message_part): + self.message_part = message_part + + def getBodyFile(self, store=None): + return self.message_part.get_body_file() + + def getSize(self): + return self.message_part.get_size() + + def getHeaders(self, negate, *names): + headers = self.message_part.get_headers() + return _format_headers(headers, negate, *names) + + def isMultipart(self): + return self.message_part.is_multipart() + + def getSubPart(self, part): + subpart = self.message_part.get_subpart(part + 1) + return IMAPMessagePart(subpart) + + +def _format_headers(headers, negate, *names): + # current server impl. expects content-type to be present, so if for + # some reason we do not have headers, we have to return at least that + # one + if not headers: + logger.warning("No headers found") + return {str('content-type'): str('')} + + names = map(lambda s: s.upper(), names) + + if negate: + def cond(key): + return key.upper() not in names + else: + def cond(key): + return key.upper() in names + + if isinstance(headers, list): + headers = dict(headers) + + # default to most likely standard + charset = find_charset(headers, "utf-8") + + # We will return a copy of the headers dictionary that + # will allow case-insensitive lookups. In some parts of the twisted imap + # server code the keys are expected to be in lower case, and in this way + # we avoid having to convert them. + + _headers = CaseInsensitiveDict() + for key, value in headers.items(): + if not isinstance(key, str): + key = key.encode(charset, 'replace') + if not isinstance(value, str): + value = value.encode(charset, 'replace') + + if value.endswith(";"): + # bastards + value = value[:-1] + + # filter original dict by negate-condition + if cond(key): + _headers[key] = value + + return _headers |