websocket client 如何发起

    $con = new AsyncTcpConnection('ws://echo.websocket.org:80');

    // websocket握手成功后
    $con->onWebSocketConnect = function(AsyncTcpConnection $con, ) {
        $con->send('hello');
    };

    // 当收到消息时
    $con->onMessage = function(AsyncTcpConnection $con, $data) {
        echo $data;
    };

    $con->connect();