protected function execute(InputInterface $input, OutputInterface $output)
    {
        $loop = Factory::create();
        $pusher = new Notification();

        $context = new Context($loop);
        $pull = $context->getSocket(ZMQ::SOCKET_PULL);
        $webSock = new Server('127.0.0.1:8080', $loop);
        $pull->bind('tcp://127.0.0.1:5555');
        $pull->on('message', array($pusher, 'onTest'));
        $webServer = new IoServer(
            new HttpServer(
                new WsServer(
                    new Notification()
                )
            ),
            $webSock
        );

        $loop->run();
    }

protected function execute(InputInterface $input, OutputInterface $output)
    {
        $context = new ZMQContext();
        $socket = $context->getSocket(ZMQ::SOCKET_PUSH, 'onTest');
        $socket->connect('tcp://localhost:5555');
        $socket->send('Test message');
    }

class Notification implements MessageComponentInterface
{
    protected $clients;

    public function __construct()
    {
        $this->clients = new SplObjectStorage();
    }

    public function onOpen(ConnectionInterface $conn)
    {
        $this->clients->attach($conn);
    }

    public function onClose(ConnectionInterface $conn)
    {
        $this->clients->detach($conn);
    }

    public function onError(ConnectionInterface $conn, Exception $e)
    {
        $conn->close();
    }

    public function onMessage(ConnectionInterface $from, $msg)
    {
        //auth user etc
    }

    public function onTest($entry)
    {
        //this array is always empty
        foreach ($this->clients as $client) {
            $client->send('send new message');
        }
    }
 }