Python Network Programming

How to do it...

Listing 5.8 shows us the code that finds the domain name from the given email address and verifies it:

#!/usr/bin/env python 
# Python Network Programming Cookbook, Second Edition -- Chapter - 5 
# This program is optimized for Python 2.7.12 and Python 3.5.2. 
# It may run on any other version with/without modifications. 
 
import re 
import smtplib 
import dns.resolver 
import argparse 
 
 
def mail_checker(fromAddress, toAddress): 
 
    regex = '^[a-z0-9][a-z0-9._%+-]{0,63}@[a-z0-9-]+            (\.[a-z0-9-]+)*(\.[a-z]{2,})$' 
 
    addressToVerify = str(toAddress) 
 
    match = re.match(regex, addressToVerify) 
    if match == None: 
       print('Bad Syntax in the address to verify. Re-enter the correct value') raise ValueError('Bad Syntax') splitAddress = addressToVerify.split('@') ...