Php Ratchet ??� how to track a connection break?

one text

How to track a connection break in Ratchet - I use an example from the main page. But when the client breaks the connection (that is, it does not close it, but for example when the network drops and the connection is lost), the onClose or onError methods are not called... how do I track such a connection - I want to do some actions when it breaks.

example

<?php
use Ratchet\MessageComponentInterface;
use Ratchet\ConnectionInterface;

    // Make sure composer dependencies have been installed
    require __DIR__ . '/vendor/autoload.php';

/**
 * chat.php
 * Send any incoming messages to all connected clients (except sender)
 */
class MyChat implements MessageComponentInterface {
    protected $clients;

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

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

    public function onMessage(ConnectionInterface $from, $msg) {
        foreach ($this->clients as $client) {
            if ($from != $client) {
                $client->send($msg);
            }
        }
    }

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

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

    // Run the server application through the WebSocket protocol on port 8080
    $app = new Ratchet\App('localhost', 8080);
    $app->route('/chat', new MyChat, array('*'));
    $app->route('/echo', new Ratchet\Server\EchoServer, array('*'));
    $app->run();

If the network interface is turned off on the client, the connection will be broken, but the onClose or onError methods will not be called. How do I detect and process a connection break?