Simple python mail notification utility

mail_notify.py

#!/usr/bin/env python

# Copyright (C) 2015 Aaron Conole <aconole@bytheb.org>
# I cobbled this together looking for a really lightweight mail
# notification utility to couple with emacs. I never found
# a solution - this fits the bill for my needs
# 
# LICENSE: GPLv2 with the caveat that it cannot be upgraded
#          to GPLv3

import datetime
import imaplib2
import socket
import os
import re
import notify2
from threading import Thread
from threading import Event
import ConfigParser

t2 = datetime.datetime.now()

class _Configurations(object):
    def __init__(self):
        self.config = ConfigParser.ConfigParser()
        self.config.read(os.getenv("HOME")+"/.mail_notify")

    def __repr__(self):
        srepr = "\"mail_notify\": {\n"
        for ItemName,ItemVal in self.config.items('default'):
            srepr += "\"%s\": %s\n" % (ItemName, ItemVal)
        srepr += "}\n"
        return srepr

    def FindOptionVal(self, OptionName):
        for option in self.config.options('default'):
            if option.lower() == OptionName.lower():
                return self.config.get('default', OptionName)

        return None

# This is the threading object that does all the waiting on 
# the event
class _Idler(object):
    def __init__(self, conn):
        self.thread = Thread(target=self.idle)
        self.M = conn
        self.event = Event()

    def start(self):
        self.thread.start()

    def stop(self):
        self.event.set()

    def join(self):
        self.thread.join()

    def idle(self):
        while True:
            if self.event.isSet():
                return
            self.needsync = False
            def callback(args):
                if not self.event.isSet():
                    self.needsync = True
                    self.event.set()
            self.M.idle(callback=callback)
            self.event.wait()
            if self.needsync:
                self.event.clear()
                self.dosync()

    # The method that gets called when a new email arrives. 
    def dosync(self):
        n = notify2.Notification("New Mail Arrived",
                                 "You've received new mail",
                                 "notification-message-im")
        n.show()

def _GetGPGAuthInfoData(filename):
    binary = "/usr/bin/gpg"
    if _Configurations().FindOptionVal('gpg-binary') != None:
        binary = _Configurations().FindOptionVal('gpg-binary')

    if os.environ.get('GPG_AGENT_INFO') != None:
        binary += " --use-agent"

    cmd = "%s -q --no-tty -d %s" % (binary, filename)

    authinfo = os.popen(cmd).read()
    return authinfo

def _GetAuthInfoData():

    filename = os.environ['HOME']

    if os.path.isfile(filename + "/.authinfo.gpg"):
        authinfo = _GetGPGAuthInfoData(filename + "/.authinfo.gpg")
    elif os.path.isfile(filename + "/.authinfo"):
        authinfo = open(filename + "/.authinfo").read()
    elif os.path.isfile(filename + "/.netrc"):
        authinfo = open(filename + "/.netrc")
    else:
        print "No authinfo or netrc file found..."
        return None
    return authinfo

def _GetImapObject():
    cfg = _Configurations()
    machine = cfg.FindOptionVal('machine')
    user = cfg.FindOptionVal('login')

    data = _GetAuthInfoData()

    if user is None:
        user = "([^\W]*)"

    p = re.search("machine %s login %s password ([^\W]*) (port )?([^\W]*)?" % (machine, user),
                  data)

    if p is None:
        return None

    pgroup = 1

    if user == "([^\W]*)":
        user = p.group(pgroup)
        pgroup += 1

    password = p.group(pgroup)

    port = "143"

    if p.group(pgroup+1) is not None:
        port = p.group(pgroup+2)
        if port.isdigit() == False:
            port = socket.getservbyname(port, 'tcp')
    
    if cfg.FindOptionVal('ssl') is None or cfg.FindOptionVal('ssl').lower() == "true":
        M = imaplib2.IMAP4_SSL(machine, port)
    else:
        M = imaplib2.IMAP4(machine, port)

    M.login(user, password)
    M.select("INBOX")
    return M

def _Daemonize():
    def dofork():
        try:
            pid = os.fork()
        except OSError, e:
            raise Exception, "%s [%d]" % (e.strerror, e.errno)
        return pid

    pid = dofork()

    if pid == 0:
        os.setsid()
        
        pid = dofork()
        if pid == 0:
            os.chdir(os.environ['HOME'])

            os.umask(0200)
        else:
            os._exit(0)
            
    else:
        os._exit(0)

    os.open("/dev/null", os.O_RDWR)
    os.dup2(0, 1)
    os.dup2(0, 2)

    return 0
        
def main():
    _Daemonize()

    notify2.init('Mail Notifier')
    
    M = _GetImapObject()
    idl = _Idler(M)
    
    idl.start()
    idl.join()

if __name__ == '__main__':
    main()