How can I send and receive WebSocket messages on the server side?

Question

• How can I send and receive messages on the server side using WebSocket, as per the protocol?

• Why do I get seemingly random bytes at the server when

Answer 1

In addition to the PHP frame encoding function, here follows a decode function:

function Decode($M){
    $M = array_map("ord", str_split($M));
    $L = $M[1] AND 127;

    if ($L == 126)
        $iFM = 4;
    else if ($L == 127)
        $iFM = 10;
    else
        $iFM = 2;

    $Masks = array_slice($M, $iFM, 4);

    $Out = "";
    for ($i = $iFM + 4, $j = 0; $i < count($M); $i++, $j++ ) {
        $Out .= chr($M[$i] ^ $Masks[$j % 4]);
    }
    return $Out;
}

I've implemented this and also other functions in an easy-to-use WebSocket PHP class here.