Connecting to websocket with PHP client

Question

I'm trying to connect a PHP-based client to a websocket server.

Here's the code I have been using which has been widely published on different forums. But for some reason I just cannot get it to work.

Any help would be appreciated.

$host = 'host';  //where is the websocket server
$port = 443; //ssl
$local = "http://www.example.com/";  //url where this script run
$data = '{"id": 2,"command": "server_info"}';  //data to be send

$head =        "GET / HTTP/1.1"."\r\n".
               "Upgrade: WebSocket"."\r\n".
               "Connection: Upgrade"."\r\n".
               "Origin: $local"."\r\n".
               "Host: $host"."\r\n".
               "Content-Length: ".strlen($data)."\r\n"."\r\n";
////WebSocket handshake
$sock = fsockopen($host, $port, $errno, $errstr, 2);
fwrite($sock, $head ) or die('error:'.$errno.':'.$errstr);
$headers = fread($sock, 2000);
fwrite($sock, "\x00$data\xff" ) or die('error:'.$errno.':'.$errstr);
$wsdata = fread($sock, 2000);  //receives the data included in the websocket package "\x00DATA\xff"
$retdata = trim($wsdata,"\x00\xff"); //extracts data
////WebSocket handshake
fclose($sock);

echo $retdata;

Answer 1

I would probably prefer to use an existing websocket client library (maybe https://github.com/gabrielbull/php-websocket-client or https://github.com/Devristo/phpws/tree/master/src/Devristo/Phpws/Client ?) rather than roll your own, but I got it to at least connect by using:

$head = "GET / HTTP/1.1"."\r\n".
    "Host: $host"."\r\n".
    "Upgrade: websocket"."\r\n".
    "Connection: Upgrade"."\r\n".
    "Sec-WebSocket-Key: asdasdaas76da7sd6asd6as7d"."\r\n".
    "Sec-WebSocket-Version: 13"."\r\n".
    "Content-Length: ".strlen($data)."\r\n"."\r\n";

My server is using TLS/SSL, so I also needed:

$sock = fsockopen('tls://'.$host, $port, $errno, $errstr, 2);

The full protocol spec is: https://tools.ietf.org/rfc/rfc6455.txt