~bzr-pqm/bzr/bzr.dev

2625.6.1 by Adeodato Simó
New EmailMessage class, façade around email.Message and MIMEMultipart.
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# Copyright (C) 2007 Canonical Ltd
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#
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation; either version 2 of the License, or
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# (at your option) any later version.
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#
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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# GNU General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with this program; if not, write to the Free Software
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# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
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"""A convenience class around email.Message and email.MIMEMultipart."""
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from email import (
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    Header,
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    Message,
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    MIMEMultipart,
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    MIMEText,
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    Utils,
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    )
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from bzrlib import __version__ as _bzrlib_version
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from bzrlib.osutils import safe_unicode
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from bzrlib.smtp_connection import SMTPConnection
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2625.6.3 by Adeodato Simó
Changes after review by John.
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class EmailMessage(object):
2625.6.1 by Adeodato Simó
New EmailMessage class, façade around email.Message and MIMEMultipart.
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    """An email message.
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    The constructor needs an origin address, a destination address or addresses
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    and a subject, and accepts a body as well. Add additional parts to the
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    message with add_inline_attachment(). Retrieve the entire formatted message
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    with as_string().
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    Headers can be accessed with get() and msg[], and modified with msg[] =.
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    """
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    def __init__(self, from_address, to_address, subject, body=None):
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        """Create an email message.
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        :param from_address: The origin address, to be put on the From header.
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        :param to_address: The destination address of the message, to be put in
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            the To header. Can also be a list of addresses.
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        :param subject: The subject of the message.
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        :param body: If given, the body of the message.
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        All four parameters can be unicode strings or byte strings, but for the
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        addresses and subject byte strings must be encoded in UTF-8. For the
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        body any byte string will be accepted; if it's not ASCII or UTF-8,
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        it'll be sent with charset=8-bit.
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        """
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        self._headers = {}
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        self._body = body
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        self._parts = []
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        if isinstance(to_address, basestring):
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            to_address = [ to_address ]
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        to_addresses = []
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        for addr in to_address:
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            to_addresses.append(self.address_to_encoded_header(addr))
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        self._headers['To'] = ', '.join(to_addresses)
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        self._headers['From'] = self.address_to_encoded_header(from_address)
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        self._headers['Subject'] = Header.Header(safe_unicode(subject))
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        self._headers['User-Agent'] = 'Bazaar (%s)' % _bzrlib_version
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    def add_inline_attachment(self, body, filename=None, mime_subtype='plain'):
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        """Add an inline attachment to the message.
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        :param body: A text to attach. Can be an unicode string or a byte
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            string, and it'll be sent as ascii, utf-8, or 8-bit, in that
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            preferred order.
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        :param filename: The name for the attachment. This will give a default
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            name for email programs to save the attachment.
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        :param mime_subtype: MIME subtype of the attachment (eg. 'plain' for
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            text/plain [default]).
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        The attachment body will be displayed inline, so do not use this
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        function to attach binary attachments.
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        """
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        # add_inline_attachment() has been called, so the message will be a
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        # MIMEMultipart; add the provided body, if any, as the first attachment
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        if self._body is not None:
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            self._parts.append((self._body, None, 'plain'))
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            self._body = None
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        self._parts.append((body, filename, mime_subtype))
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    def as_string(self, boundary=None):
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        """Return the entire formatted message as a string.
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        :param boundary: The boundary to use between MIME parts, if applicable.
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            Used for tests.
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        """
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        if not self._parts:
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Some cleanups for the EmailMessage class.
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            msgobj = Message.Message()
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New EmailMessage class, façade around email.Message and MIMEMultipart.
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            if self._body is not None:
2625.6.3 by Adeodato Simó
Changes after review by John.
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                body, encoding = self.string_with_encoding(self._body)
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                msgobj.set_payload(body, encoding)
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        else:
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Some cleanups for the EmailMessage class.
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            msgobj = MIMEMultipart.MIMEMultipart()
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            if boundary is not None:
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                msgobj.set_boundary(boundary)
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            for body, filename, mime_subtype in self._parts:
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Changes after review by John.
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                body, encoding = self.string_with_encoding(body)
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                payload = MIMEText.MIMEText(body, mime_subtype, encoding)
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                if filename is not None:
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                    content_type = payload['Content-Type']
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                    content_type += '; name="%s"' % filename
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                    payload.replace_header('Content-Type', content_type)
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                payload['Content-Disposition'] = 'inline'
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                msgobj.attach(payload)
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        # sort headers here to ease testing
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        for header, value in sorted(self._headers.items()):
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            msgobj[header] = value
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2639.1.2 by John Arbash Meinel
Some cleanups for the EmailMessage class.
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        return msgobj.as_string()
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    __str__ = as_string
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    def get(self, header, failobj=None):
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        """Get a header from the message, returning failobj if not present."""
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        return self._headers.get(header, failobj)
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    def __getitem__(self, header):
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        """Get a header from the message, returning None if not present.
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Changes after review by John.
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        This method intentionally does not raise KeyError to mimic the behavior
2625.6.1 by Adeodato Simó
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        of __getitem__ in email.Message.
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        """
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        return self._headers.get(header, None)
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    def __setitem__(self, header, value):
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        return self._headers.__setitem__(header, value)
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    @staticmethod
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    def send(config, from_address, to_address, subject, body, attachment=None,
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            attachment_filename=None, attachment_mime_subtype='plain'):
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        """Create an email message and send it with SMTPConnection.
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        :param config: config object to pass to SMTPConnection constructor.
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        See EmailMessage.__init__() and EmailMessage.add_inline_attachment()
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        for an explanation of the rest of parameters.
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        """
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        msg = EmailMessage(from_address, to_address, subject, body)
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        if attachment is not None:
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            msg.add_inline_attachment(attachment, attachment_filename,
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                    attachment_mime_subtype)
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        SMTPConnection(config).send_email(msg)
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    @staticmethod
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    def address_to_encoded_header(address):
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        """RFC2047-encode an address if necessary.
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        :param address: An unicode string, or UTF-8 byte string.
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        :return: A possibly RFC2047-encoded string.
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        """
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        # Can't call Header over all the address, because that encodes both the
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        # name and the email address, which is not permitted by RFCs.
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        user, email = Utils.parseaddr(address)
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        if not user:
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            return email
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        else:
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            return Utils.formataddr((str(Header.Header(safe_unicode(user))),
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                email))
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    @staticmethod
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Changes after review by John.
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    def string_with_encoding(string_):
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        """Return a str object together with an encoding.
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Changes after review by John.
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        :param string_: A str or unicode object.
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        :return: A tuple (str, encoding), where encoding is one of 'ascii',
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            'utf-8', or '8-bit', in that preferred order.
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        """
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        # Python's email module base64-encodes the body whenever the charset is
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        # not explicitly set to ascii. Because of this, and because we want to
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        # avoid base64 when it's not necessary in order to be most compatible
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        # with the capabilities of the receiving side, we check with encode()
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        # and decode() whether the body is actually ascii-only.
2625.6.3 by Adeodato Simó
Changes after review by John.
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        if isinstance(string_, unicode):
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            try:
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Changes after review by John.
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                return (string_.encode('ascii'), 'ascii')
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            except UnicodeEncodeError:
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                return (string_.encode('utf-8'), 'utf-8')
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        else:
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            try:
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                string_.decode('ascii')
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                return (string_, 'ascii')
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            except UnicodeDecodeError:
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                try:
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                    string_.decode('utf-8')
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                    return (string_, 'utf-8')
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                except UnicodeDecodeError:
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                    return (string_, '8-bit')