A script to print a mail delivered on stdin

mailprint.py

#!/usr/bin/env python
# could be added to .forward with "|$PATH/mailprint.py"
import sys
import email.feedparser as mailparser

"""
TODO
====

* add quota
* filter for sender / X-Originating-IP
* add more file types
* add printig code
* if possible validate file size
* forward errors to sender (the guy who wants to print)
    * log to webpage?
    * send mail back? (attention spam!)
    * bounce? (not possible as i see it)
* what is about malware? (print me if you dare)

"""


def parse():
    parser = mailparser.FeedParser()
    
    for data in sys.stdin:
        parser.feed(data)
    
    email = parser.close()
    print('Done with parsing')
    
    if email and email.is_multipart():
        return email
    else:
        print('This is either no mime mail, or a mail without attachments')


def process(email):
    attachments = {}
    to_print = []
    valid_content_types = ['application/pdf','text/x-python']

    for part in email.get_payload():
        # dirty way to test whether this part is a attachment
        if part.get_filename() and (part.get_content_type() in valid_content_types):
            attachments[part.get_filename()] = part
        elif part.get_content_type() == 'text/plain':
            to_print = part.get_payload().rsplit('\n')
        else:
            print('Dropping part of mime-type %s' % part.get_content_type())

    for filename in to_print:
        if filename in attachments:
            print('Would print %s' % filename)

if __name__ == "__main__":
    mail = parse()
    if mail:
        process(mail)