Allow queueing but not performing php resque

PerformLock.php

<?php
/**
 * @file
 * Contains Drupal\resque\PerformLockPlugin.
 */

namespace Drupal\resque;

use Resque as Php_Resque;
use Resque_Job_DontPerform;

class PerformLockPlugin{
  function beforePerform($job) {
    if (Php_Resque::redis()->exists($arguments['drupal_unique_key'])) {
      throw new Resque_Job_DontPerform('Unique key conflict.');
      $job->recreate();
    }
  }
}

?>