how to rectify [PHP Fatal error: Interface 'Ratchet\MessageComponentInterface' not found ] in ratchet

[shan2batman]

I'm trying to create a basic websocket chat from a tutorial in YouTube and I'am facing this error in the terminal when i run 

 

> php bin/server.php

 

 

 

Fatal error:** Interface 'Ratchet\MessageComponentInterface' not found in /var/www/html/websocket/bin/chat.php on line 6

 

 

 

My code is as follows for chat.php:-

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


    class chat 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 onMessage(ConnectionInterface $conn,$msg)
                {
                    foreach($this->clients as $client){
                        if($client !==$conn){
                            $client->send($msg);
                        }
                    }
                }


            public function onError(ConnectionInterface $conn, \Exception $e)
                {
                    echo "the following error occured: ".$e->getMessage();
                     $conn->close();
                }
        }

code for server.php:-

 

    <?php
    require 'chat.php';
    require __DIR__ .'/vendor/autoload.php';
    use Ratchet\Server\IoServer;
    use Ratchet\Http\HttpServer;
    use Ratchet\WebSocket\WsServer;
    
    $server=IoServer::factory(new HttpServer(new WsServer (new chat())) , 8080);
    $server->run();

Any help would be appreciated.