How to send data to websocket from server-side (without zmq extension)?
How can i do, to send data from my server-side for my $this->subscriptions connections in websocket?

- websocket.php (called in cmd)
```
<?php
require_once '../vendor/autoload.php';

$nws = new \src\models\NotifyWebSocket;

$app = new \Ratchet\App('localhost', 8080);
$app->route('/website/wss/notify', $nws, array('*'));
$app->run();

```

- Class NotifyWebSocket.php
```
<?php
namespace src\models;

use \core\Model;
use \Ratchet\MessageComponentInterface;
use \Ratchet\ConnectionInterface;

class NotifyWebSocket extends Model implements MessageComponentInterface 
{
    protected $clients;
    private $subscriptions;
    private $users;

    public function __construct()
    {
        $this->clients = new \SplObjectStorage;
        $this->subscriptions = [];
        $this->users = [];
    }

    public function onOpen(ConnectionInterface $conn) 
    {
        $this->clients->attach($conn);
        $this->users[$conn->resourceId] = $conn;

        echo "New connection! ({$conn->resourceId})\n";
    }

    public function onMessage(ConnectionInterface $conn, $msg) 
    {
        $dados = json_decode($msg, true);

        switch ($dados['comando']) {
            case "subscribe":
                $this->subscriptions[$conn->resourceId] = $data['channel'];
                break;
            case "message":
                foreach ($this->subscriptions as $id => $employee) {
                    $this->users[$id]->send($msg);
                }
                break;
        }
    }

    public function onClose(ConnectionInterface $conn) 
    {
        $this->clients->detach($conn);
        unset($this->users[$conn->resourceId]);
        unset($this->subscriptions[$conn->resourceId]);

        echo "Connection {$conn->resourceId} has disconnected\n";
    }

    public function onError(ConnectionInterface $conn, \Exception $e) 
    {
        var_dump("An error has occurred: {$e->getMessage()}\n");
        $conn->close();
    }
}
```