/**
  * @return array
  */
 public function getMessage($identifier)
 {
     $pheanstalkJob = $this->client->peek($identifier);
     if ($pheanstalkJob === null || $pheanstalkJob === false) {
         return null;
     }
     $message = $this->decodeMessage($pheanstalkJob->getData());
     $message->setIdentifier($pheanstalkJob->getId());
     return $message;
 }