Find long-running tasks in Ansible logs by prepending elapsed time for each entry in a log file

tansible.php

<?php
  // This script prepends the elapsed time for each entry of an Ansible log
  // file (see: http://stackoverflow.com/q/34211898/147937 for inspiration and
  // additional background information). This script is intended to be used
  // only on the "TASK:" lines from the logs. For example:
  //    $ grep "TASK:" ansible.log | php ~/tansible.php
  while(!feof(STDIN)) {
    $line = fgets(STDIN);
    $exploded_line = explode(' ', $line);
    if (isset($exploded_line[1])) {
      $exploded_time = explode(',', $exploded_line[1]);
    }
    else {
      exit();
    }
    $hms = $exploded_time[0];
    if (isset($previous_line)) {
      $difference = strtotime($hms) - strtotime($previous_time);
      if ($difference > 60) {
        echo(gmdate("H:i:s", $difference) . ' ' . $previous_line . PHP_EOL);
      }
    }
    $previous_line = $line;
    $previous_time = $hms;
  }