public function reply(Worker $worker, MessageInterface $msg)
    {
        if (!$worker->isReady()) {
            $this->getLogger()->debug(
                'Worker '.$worker->getHexId().' is not ready to receive data.');

            return;
        }
        $worker->setReady(false);

        if (!$worker->isValid()) {
            $this->getLogger()->debug(
                'Worker '.$worker->getHexId().' is not valid, destroying.');
            $msg = new Destroy();
        }

        $this->getStream('worker')->send($msg, $worker->getId());
    }