php store data in socket

Question

I would like to know, how do you store date in socket stream ?

I'm learning php socket atm, and for example, if i want to make an online users list : People on the webpage have a session[username]. I want to link it to the IP address in socket clients list.

I don't want to get the session_id of the client in socket page, i would like to send the username to that socket page (via javascript socket.onopen) and then the username would be stored until connection end.

Is that possible ?

EDIT

/* SERVER DATA
=======================================================*/
$host = '127.0.0.1'; //host
$port = '8090'; //port
$null = NULL; //null var

//Create TCP/IP, IPv4 stream socket
$socket = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);

//Reuseable port
socket_set_option($socket, SOL_SOCKET, SO_REUSEADDR, 1);

//Bind socket to specified host
socket_bind($socket, 0, $port);

//Listen to port
socket_listen($socket);

//Create & add listening socket to the list
$clients = array($socket);

//Start endless loop, so that our script doesn't stop
while (true) {
    //Manage multiple connections
    $changed = $clients;

    //Returns the socket resources in $changed array
    socket_select($changed, $null, $null, 0, 10);

    //Check for new socket
    if (in_array($socket, $changed)) {
        $socket_new = socket_accept($socket); //accept new socket
        $clients[] = $socket_new; //add socket to client array

        $header = socket_read($socket_new, 1024); //read data sent by the socket
        perform_handshaking($header, $socket_new, $host, $port); //perform websocket handshake

        socket_getpeername($socket_new, $ip); //get ip address of connected socket
        $response = mask(json_encode(array('type'=>'system_user_conn', 'message'=>$ip))); //prepare json data
        send_message($response); //notify all users about new connection

        //make room for new socket
        $found_socket = array_search($socket, $changed);
        unset($changed[$found_socket]);
    }

    //loop through all connected sockets
    foreach ($changed as $changed_socket) { 

        //check for any incomming data
        while(socket_recv($changed_socket, $buf, 1024, 0) >= 1)
        {
            $received_text = unmask($buf); //unmask data
            $tst_msg = json_decode($received_text); //json decode 
            $user_name = $tst_msg->name; //sender name
            $user_message = $tst_msg->message; //message text

            //prepare data to be sent to client
            $response_text = mask(json_encode(array('type'=>'usermsg', 'name'=>$user_name, 'message'=>$user_message)));
            send_message($response_text); //send data
            break 2; //exist this loop
        }

        $buf = @socket_read($changed_socket, 1024, PHP_NORMAL_READ);
        if ($buf === false) { // check disconnected client
            // remove client for $clients array
            $found_socket = array_search($changed_socket, $clients);
            socket_getpeername($changed_socket, $ip);
            unset($clients[$found_socket]);

            //notify all users about disconnected connection
            $response = mask(json_encode(array('type'=>'system', 'message'=>$ip.' disconnected')));
            send_message($response);
        }
    }
}
// close the listening socket
socket_close($socket);

function send_message($msg)
{
    global $clients;
    foreach($clients as $changed_socket)
    {
        @socket_write($changed_socket,$msg,strlen($msg));
    }
    return true;
}


//Unmask incoming framed message
function unmask($text) {
    $length = ord($text[1]) & 127;
    if($length == 126) {
        $masks = substr($text, 4, 4);
        $data = substr($text, 8);
    }
    elseif($length == 127) {
        $masks = substr($text, 10, 4);
        $data = substr($text, 14);
    }
    else {
        $masks = substr($text, 2, 4);
        $data = substr($text, 6);
    }
    $text = "";
    for ($i = 0; $i < strlen($data); ++$i) {
        $text .= $data[$i] ^ $masks[$i%4];
    }
    return $text;
}

//Encode message for transfer to client.
function mask($text)
{
    $b1 = 0x80 | (0x1 & 0x0f);
    $length = strlen($text);

    if($length <= 125)
        $header = pack('CC', $b1, $length);
    elseif($length > 125 && $length < 65536)
        $header = pack('CCn', $b1, 126, $length);
    elseif($length >= 65536)
        $header = pack('CCNN', $b1, 127, $length);
    return $header.$text;
}

//handshake new client.
function perform_handshaking($receved_header,$client_conn, $host, $port)
{
    $headers = array();
    $lines = preg_split("/\r\n/", $receved_header);
    foreach($lines as $line)
    {
        $line = chop($line);
        if(preg_match('/\A(\S+): (.*)\z/', $line, $matches))
        {
            $headers[$matches[1]] = $matches[2];
        }
    }

    $secKey = $headers['Sec-WebSocket-Key'];
    $secAccept = base64_encode(pack('H*', sha1($secKey . '258EAFA5-E914-47DA-95CA-C5AB0DC85B11')));
    //hand shaking header
    $upgrade  = "HTTP/1.1 101 Web Socket Protocol Handshake\r\n" .
    "Upgrade: websocket\r\n" .
    "Connection: Upgrade\r\n" .
    "WebSocket-Origin: $host\r\n" .
    "WebSocket-Location: ws://$host:$port/demo/shout.php\r\n".
    "Sec-WebSocket-Accept:$secAccept\r\n\r\n";
    socket_write($client_conn,$upgrade,strlen($upgrade));
}

I would like to send 'message'=>$username. At this line :

$response = mask(json_encode(array('type'=>'system_user_conn', 'message'=>$ip))); //prepare json data

When i'm using on send data (javascript), i re-send the username all the time, like this :

$('#frmChat').on("submit",function(event){
                event.preventDefault();
                var messageJSON = {
                    type: 'usrmsg',
                    name: '<?php echo $SESSION['pseudo']; ?>',
                    message: $('#chat-message').val()
                };
                websocket.send(JSON.stringify(messageJSON));
            });

I'm looking for a way to store the username. Not to re-send it all the time. It will help me to create an "online users" list.

Thank you in advance.

Answer 1

Why would you do that? You can just use the PHP Session Variable to check if a user is logged in. You can specify the time a session will be stored in the PHP configuration. You can also remove the session if needed.