Process received email with Python or Django?

Question

I understand how sending email works through Django, but I want users to be able to respond to the email. If the email they send (and I receive) contains a message that matches

Answer 1

We are doing something similar with plone by configuring postfix to do a HTTP request to plone when receiving an email to a specific domain. This should also easily be possible with django, so that you just have to configure your server and write a view in django which receives the email.

That's how you can do it:

1) Set up your DNS so that a MX record for the domain points to your server.

2) Configure a postfix virtual alias /etc/postfix/virtual:

example.com anything
django@example.com django-mail-in

3) and /etc/aliases:

django-mail-in: "|/usr/local/bin/mta2django.py http://127.0.0.1:8000/mail-inbound"

4) The /usr/local/bin/mta2django.py is called by postscript and sends the mail to the mail-inbound django view. This mta2django.py should work:

#!/usr/bin/python

import sys, urllib
import os


def post_message(url, recipient, message_txt):
    """ post an email message to the given url
    """

    if not url:
        print "Invalid url."
        print "usage: mta2django.py url "
        sys.exit(64)

    data = {'mail': message_txt}
    if recipient and len(recipient) > 0:
        data ['recipient'] = recipient

    try:
        result = urllib.urlopen(url, urllib.urlencode(data)).read()
    except (IOError,EOFError),e:
        print "error: could not connect to server",e
        sys.exit(73)

    try:
        exitcode, errormsg = result.split(':')
        if exitcode != '0':
            print 'Error %s: %s' % (exitcode, errormsg)
            sys.exit(int(exitcode))
    except ValueError:
        print 'Unknown error.'
        sys.exit(69)

    sys.exit(0)


if __name__ == '__main__':
    # This gets called by the MTA when a new message arrives.
    # The mail message file gets passed in on the stdin

    # Get the raw mail
    message_txt = sys.stdin.read()

    url = ''
    if len(sys.argv)>1:
        url = sys.argv[1]

    recipient = ''
    # If mta2django is executed as external command by the MTA, the
    # environment variable ORIGINAL_RECIPIENT contains the entire
    # recipient address, before any address rewriting or aliasing
    recipient = os.environ.get('ORIGINAL_RECIPIENT')

    if len(sys.argv)>2:
        recipient = sys.argv[2]

    post_message(url, recipient, message_txt)

5) Write a django view /mail-inbound which receives the mail and does the things you need it to do. In the request you have:

• mail - the full email message
• recipient - the original recipient (useful when you do not catch a specific email address but the whole domain / subdomain)

You can parse the email using the python email module:

import email

msg = email.message_from_string(request.get('mail'))

As I'm no postfix expert, I'm not sure if editing /etc/postfix/virtual and /etc/aliases is sufficient. Please consult the postfix documentation for details.