main_multithreading.py

from tkinter import Tk
from tkinter.filedialog import askopenfilename, asksaveasfilename
from joblib import Parallel, delayed
from unknown_encoding import *
import re
import dns.resolver
import smtplib


def main():
    print("Program: Email Ping")
    print("Release: 1.1.1")
    print("Date: 2019-09-23")
    print("Author: Brian Neely")
    print()
    print()
    print("This program pings a email web server for a specified email address in a csv.")
    print("It assumes that the csv file is encoded in UTF-8 and is comma delimited.")
    print(
        "A significant portion of the ping_email function is copied from the work of Scott Brady from his Python-Email-Verification-Script")
    print("His work and this work is licensed under the Apache License 2.0")
    print()
    print()

    print("Program Starting")
    # Hide Tkinter GUI
    Tk().withdraw()

    # Find input file
    print("Select File in")
    file_in = askopenfilename(initialdir="../", title="Select input file",
                              filetypes=(("Comma Separated Values", "*.csv"), ("all files", "*.*")))
    if not file_in:
        input("Program Terminated. Press Enter to continue...")
        exit()

    # Set output file
    file_out = asksaveasfilename(initialdir=file_in, title="Select output file",
                                 filetypes=(("Comma Separated Values", "*.csv"), ("all files", "*.*")))
    if not file_out:
        input("Program Terminated. Press Enter to continue...")
        exit()

    # Identify CSV Encoding
    data = open_unknown_csv(file_in, ",")

    # Find email column
    email_col = column_selection(list(data))

    # Test each email address
    email_list = Parallel(n_jobs=60)(delayed(ping, 10)(i, index) for index, i in enumerate(data[email_col]))
    data["Email Validity"] = email_list

    # Write CSV
    print("Writing CSV File...")
    data.to_csv(file_out, index=False)
    print("Wrote CSV File!")
    print()

    print("File written to: " + file_out)
    print("Error codes can be found at: {https://serversmtp.com/smtp-error/}")
    input("Press Enter to close...")


def column_selection(headers):
    while True:
        try:
            print("Select column.")
            for j, i in enumerate(headers):
                print(str(j) + ": to ping column [" + str(i) + "]")
            column = headers[int(input("Enter Selection: "))]
        except ValueError:
            print("Input must be integer between 0 and " + str(len(headers)))
            continue
        else:
            break
    return column


def ping(i, index):
    # print('')
    if index % 100 == 0:
        print(str(index) + ": " + str(i))
    try:
        return ping_email(i)
    except:
        return "Domain Doesn't Exist"


def ping_email(inputAddress):
    # Print what email is being tested
    # print("Testing: " + inputAddress)

    # Address used for SMTP MAIL FROM command
    fromAddress = 'noresponse@gmail.com'

    # Simple Regex for syntax checking
    regex = '^[_a-z0-9-]+(\.[_a-z0-9-]+)*@[a-z0-9-]+(\.[a-z0-9-]+)*(\.[a-z]{2,})$'

    # Email address to verify
    addressToVerify = str(inputAddress)

    # Lower case address
    addressToVerify = addressToVerify.lower()

    # Syntax check
    match = re.match(regex, addressToVerify)
    if match == None:
        return 'Bad Syntax'

    # Get domain for DNS lookup
    splitAddress = addressToVerify.split('@')
    domain = str(splitAddress[1])
    # print('Domain:', domain)

    # MX record lookup
    records = dns.resolver.query(domain, 'MX')
    mxRecord = records[0].exchange
    mxRecord = str(mxRecord)

    # SMTP lib setup (use debug level for full output)
    server = smtplib.SMTP(timeout=6)
    server.set_debuglevel(0)

    # SMTP Conversation
    server.connect(mxRecord)
    server.helo(server.local_hostname)  ### server.local_hostname(Get local server hostname)
    server.mail(fromAddress)
    code, message = server.rcpt(str(addressToVerify))
    server.quit()

    if code == 250:
        return 'Success'
    elif code == 550:
        return "Email doesn't exist on server."
    elif code == 541:
        return 'Blocked by anti-spam filter.'
    else:
        return 'Other Error: ' + str(code)
    print("Code")


if __name__ == '__main__':
    main()