Process email bounces with PHP

This is a quick script to process email bounces, for example from a mailing list so that users can be flagged up or unsubscribed when they have too many failures.

The actual bounce identification will be done by Chris Fortune’s Bounce Handler, which you can download from:
http://anti-spam-man.com/php_bouncehandler/

We require 3 files from that package:
bounce_driver.class.php
bounce_responses.php
rfc1893.error.codes.php

What this script does is get the bounced emails from a specified mailbox and counts up how many failed emails there are per email address – if the number is at least as many as your threshold value (called $delete), then (you insert your code to unsubscribe the email address or whatever etc. and) the bounced emails are then deleted. You can run the script as a cronjob or call from your mailing list script to tidy up subscriptions.

<?php

# define variables
$mail_box = '{mail.domain.com:143/novalidate-cert}'; //imap example
$mail_user = 'username'; //mail username
$mail_pass = 'password'; //mail password
$delete = '5'; //deletes emails with at least this number of failures

# connect to mailbox
$conn = imap_open ($mail_box, $mail_user, $mail_pass) or die(imap_last_error());
$num_msgs = imap_num_msg($conn);

# start bounce class
require_once('bounce_driver.class.php');
$bouncehandler = new Bouncehandler();

# get the failures
$email_addresses = array();
$delete_addresses = array();
  for ($n=1;$n<=$num_msgs;$n++) {
  $bounce = imap_fetchheader($conn, $n).imap_body($conn, $n); //entire message
  $multiArray = $bouncehandler->get_the_facts($bounce);
    if (!empty($multiArray[0]['action']) && !empty($multiArray[0]['status']) && !empty($multiArray[0]['recipient']) ) {
      if ($multiArray[0]['action']=='failed') {
      $email_addresses[$multiArray[0]['recipient']]++; //increment number of failures
      $delete_addresses[$multiArray[0]['recipient']][] = $n; //add message to delete array
      } //if delivery failed
    } //if passed parsing as bounce
  } //for loop

# process the failures
  foreach ($email_addresses as $key => $value) { //trim($key) is email address, $value is number of failures
    if ($value>=$delete) {
    /*
    do whatever you need to do here, e.g. unsubscribe email address
    */
    # mark for deletion
      foreach ($delete_addresses[$key] as $delnum) imap_delete($conn, $delnum);
    } //if failed more than $delete times
  } //foreach

# delete messages
imap_expunge($conn);

# close
imap_close($conn);