notsync

#!/usr/bin/python

import ConfigParser
import imaplib
import re
import subprocess
import time
import logging
import os.path
import mailbox
from cnotmuch import notmuch

mid_regexp = re.compile('message-id:\s+\<(.*)\>', re.IGNORECASE)
ret_regexp = re.compile('([0-9]+) +.*')

# The `find_message' routine will throw an exception if the database
# is modified in another thread, so we have to retry in that case.
def mid_exists(nm, mid):
    global debug

    exists = False
    attempted = False
    while not attempted:
        try:
            exists = nm.find_message(mid)
            attempted = True
        except NotmuchError:
            logging.debug('Exception during find_message')
            pass
    return exists

def poll_server(host, user, password, directory):
    nm = notmuch.Database()

    srv = imaplib.IMAP4_SSL(host)
    srv.login(user, password)
    typ, msgnums = srv.select()
    bottom = '1'
    for top in msgnums:
        logging.debug('Checking the range %s - %s.' % (bottom, top))
        typ, data = srv.fetch('%s:%s' % (bottom, top), '(BODY.PEEK[HEADER.FIELDS (MESSAGE-ID)])')
        for mid_or_str in data:
            if type(mid_or_str) == tuple:
                (ret, mid) = mid_or_str
                mid_match = mid_regexp.match(mid)
                if mid_match:
                    mid = mid_match.group(1)
                    if not mid_exists(nm, mid):
                        logging.info('New: %s' % mid)
                        ret_match = ret_regexp.match(ret)
                        if ret_match:
                            num = ret_match.group(1)
                            typ, data = srv.fetch(num, '(RFC822)')
                            store(data[0][1], directory)
                        else:
                            logging.debug('Return code regexp did not match (%s).' % ret)
                else:
                    logging.debug('Message ID regexp did not match (%s).' % mid)
        bottom = top
    srv.close()
    srv.logout()

def delete_old(host, user, password, delay):
    # `delay' is in days.
    then = time.time() - (delay * 24 * 60 * 60)
    thenstr = time.strftime('%d-%b-%Y', time.gmtime(then))
    logging.debug('Deleting messages BEFORE %s' % thenstr)

    srv = imaplib.IMAP4_SSL(host)
    srv.login(user, password)
    typ, msgnums = srv.select()
    typ, data = srv.search(None, '(BEFORE %s)' % thenstr)
    if data[0] != '':
        # Break the request up into 100 message chunks to avoid
        # upsetting some IMAP servers with very long requests (Sun
        # Java Messaging Server at least).
        def chunks(l, n):
            for i in xrange(0, len(l), n):
                yield l[i:i+n]

        for i in chunks(data[0].split(), 100):
            logging.info('Deleting %s' % ' '.join(i))
            srv.store(','.join(i), '+FLAGS', '\\Deleted')
    srv.close()
    srv.logout()

def store(message, directory):
    # Allow for strftime formatting in the directory name.
    directory = time.strftime(directory)

    logging.debug('Maildir for store is %s' % directory)

    md = mailbox.Maildir(directory, factory = None, create = True)
    # Remove DOS line endings.
    # Is this completely safe?
    msg = mailbox.MaildirMessage(message.replace('\x0d\x0a', '\x0a'))
    md.add(msg)
    md.close()

def main():
    config = ConfigParser.ConfigParser()
    config.read(os.path.expanduser('~/.notsync.cfg'))
    log_level = logging.WARN

    if config.has_option('general', 'verbose') and \
            config.getboolean('general', 'verbose'):
        log_level = logging.INFO

    if config.has_option('general', 'debug') and \
            config.getboolean('general', 'debug'):
        log_level = logging.DEBUG

    keep = 30
    if config.has_option('general', 'keep'):
        keep = config.getint('general', 'keep')

    maildir = os.path.expanduser('~/Maildir')
    if config.has_option('general', 'maildir'):
        maildir = os.path.expanduser(config.get('general', 'maildir'))

    logging.basicConfig(level=log_level, datefmt="%Y%m%d %H:%M:%S",
                        format="%(asctime)s - %(levelname)s - %(message)s")

    for server in config.get('general', 'servers').split():
        logging.info('Polling %s...' % server)
        sub = ''
        if config.has_option(server, 'subdir'):
            sub = config.get(server, 'subdir')

        d = os.path.join(maildir, sub)

        poll_server(host = config.get(server, 'host'),
                    user = config.get(server, 'user'),
                    password = config.get(server, 'password'),
                    directory = d)

        if config.has_option('general', 'delete_mail') and \
                config.getboolean('general', 'delete_mail'):

            logging.info('Cleaning %s...' % server)
            delete_old(host = config.get(server, 'host'),
                       user = config.get(server, 'user'),
                       password = config.get(server, 'password'),
                       delay = keep)
        else:
            logging.debug('Not deleting old mail.')

if __name__ == '__main__':
    main()