The MimeWriter Module

The MimeWriter module (shown in Example 6-4) can be used to write "multipart" messages, as defined by the MIME mail standard.

Example 6-4. Using the MimeWriter Module

File: mimewriter-example-1.py import MimeWriter # data encoders import quopri import base64 import StringIO import sys TEXT = """ here comes the image you asked for. hope it's what you expected. """ FILE = "samples/sample.jpg" file = sys.stdout # # create a mime multipart writer instance mime = MimeWriter.MimeWriter(file) mime.addheader("Mime-Version", "1.0") mime.startmultipartbody("mixed") # add a text message part = mime.nextpart() part.addheader("Content-Transfer-Encoding", "quoted-printable") part.startbody("text/plain") quopri.encode(StringIO.StringIO(TEXT), file, 0) # add an image part = mime.nextpart() part.addheader("Content-Transfer-Encoding", "base64") part.startbody("image/jpeg") base64.encode(open(FILE, "rb"), file) mime.lastpart()

The output looks something like:

Content-Type: multipart/mixed; boundary='host.1.-852461.936831373.130.24813' --host.1.-852461.936831373.130.24813 Content-Type: text/plain Context-Transfer-Encoding: quoted-printable here comes the image you asked for. hope it's what you expected. --host.1.-852461.936831373.130.24813 Content-Type: image/jpeg Context-Transfer-Encoding: base64 /9j/4AAQSkZJRgABAQAAAQABAAD/2wBDAAgGBgcGBQgHBwcJCQgKDBQNDAsLDBkSEw8UHRof HBwgJC4nICIsIxwcKDcpLDAxNDQ0Hyc5PTgyPC4zNDL/2wBDAQkJCQwLDBgNDRgyIRwhMjIy ... 1e5vLrSYbJnEVpEgjCLx5mPU0qsVK0UaxjdNlS+1U6pfzTR8IzEhj2HrVG6m8m18xc8cIKSC tCuFyC746j/Cq2pTia4WztfmKjGBXTCmo6IUpt== --host.1.-852461.936831373.130.24813--

Example 6-5, which is a bit larger, uses a helper class that stores each subpart in the most suitable way.

Example 6-5. A Helper Class for the MimeWriter Module

File: mimewriter-example-2.py import MimeWriter import string, StringIO, sys import re, quopri, base64 # check if string contains non-ascii characters must_quote = re.compile("[177-377]").search # # encoders def encode_quoted_printable(infile, outfile): quopri.encode(infile, outfile, 0) class Writer: def _ _init_ _(self, file=None, blurb=None): if file is None: file = sys.stdout self.file = file self.mime = MimeWriter.MimeWriter(file) self.mime.addheader("Mime-Version", "1.0") file = self.mime.startmultipartbody("mixed") if blurb: file.write(blurb) def close(self): "End of message" self.mime.lastpart() self.mime = self.file = None def write(self, data, mimetype="text/plain"): "Write data from string or file to message" # data is either an opened file or a string if type(data) is type(""): file = StringIO.StringIO(data) else: file = data data = None part = self.mime.nextpart() typ, subtyp = string.split(mimetype, "/", 1) if typ == "text": # text data encoding = "quoted-printable" encoder = lambda i, o: quopri.encode(i, o, 0) if data and not must_quote(data): # copy, don't encode encoding = "7bit" encoder = None else: # binary data (image, audio, application, ...) encoding = "base64" encoder = base64.encode # # write part headers if encoding: part.addheader("Content-Transfer-Encoding", encoding) part.startbody(mimetype) # # write part body if encoder: encoder(file, self.file) elif data: self.file.write(data) else: while 1: data = infile.read(16384) if not data: break outfile.write(data) # # try it out BLURB = "if you can read this, your mailer is not MIME-aware " mime = Writer(sys.stdout, BLURB) # add a text message mime.write(""" here comes the image you asked for. hope it's what you expected. """, "text/plain") # add an image mime.write(open("samples/sample.jpg", "rb"), "image/jpeg") mime.close()