ratchetをしようしてwebsocketサーバーを構築する時にエラーが出る

コード
{
    "autoload": {
        "psr-0": {
            "MyApp": "src"
        }
    },
    "require": {
        "cboden/ratchet": "*"
    }
}

コード

<?php
use Ratchet\Server\IoServer;
use MyApp\Chat;

    require dirname(__DIR__) . '/vendor/autoload.php';

    $server = IoServer::factory(
        new Chat(),
        8080
    );

    $server->run();

コード
<?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) {
        // Store the new connection to send messages to later
        $this->clients->attach($conn);

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

    public function onMessage(ConnectionInterface $from, $msg) {
        $numRecv = count($this->clients) - 1;
        echo sprintf('Connection %d sending message "%s" to %d other connection%s' . "\n"
            , $from->resourceId, $msg, $numRecv, $numRecv == 1 ? '' : 's');

        foreach ($this->clients as $client) {
            if ($from !== $client) {
                // The sender is not the receiver, send to each client connected
                $client->send($msg);
            }
        }
    }

    public function onClose(ConnectionInterface $conn) {
        // The connection is closed, remove it, as we can no longer send it messages
        $this->clients->detach($conn);

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

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

        $conn->close();
    }
}

上記のコードでwebsocketのさーばーを構築しようとしたのですが、エラーが出ます。

chat-server.phpでは
Warning: require(C:\xampp\htdocs\test/vendor/autoload.php): failed to open stream: No such file or directory in C:\xampp\htdocs\test\bin\chat-server.php on line 5

Fatal error: require(): Failed opening required 'C:\xampp\htdocs\test/vendor/autoload.php' (include_path='C:\xampp\php\PEAR') in C:\xampp\htdocs\test\bin\chat-server.php on line 5

Chat.phpでは
Fatal error: Interface 'Ratchet\MessageComponentInterface' not found in C:\xampp\htdocs\test\src\MyApp\Chat.php on line 6

のように表示されます。
どのように改善すればよいですか？