public function addTask($script, $parameters, $priority)
{
$queue = new Entity\Queue();
$queue->setParameters(json_encode($parameters));
$queue->setPriority($priority);
$queue->setService($script);
$queue->setStatus(self::STATUS_NEW);
$em = $this->_doctrine->getManager();
$em->persist($queue);
$em->flush();
return $queue;
}