Code Samples: WebSocket

First you need to run server script "server.php". You can do using command prompt. Open cmd and navigate to project folder and type "php -q server.php" or browse from browser, server started. Now browse "index.php" from browser and start chatting.





One thing need to do before start server, have to check if socket is enabled in your server. Navigate to your PHP installation folder and find and edit "php.ini" file. Find the text php_sockets.dll and uncomment the line. And restart your apache server.




Below is full server.php script




<?php
$host = 'localhost'; //host
$port = '9000'; //port
$null = NULL; //null var

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

echo "Server Started...\n";
set_time_limit(60 * 2);
//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)) {
        echo "Client Connected...\n";
        $socket_new = socket_accept($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 web-socket handshake

        socket_getpeername($socket_new, $ip); //get ip address of connected socket
        $response = mask(json_encode(array('type' => 'system', 'message' => $ip . ' connected'))); //prepare json data
        send_message($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 $changed_socket) {
        //check for any incoming data
        try {
            while (socket_recv($changed_socket, $buf, 1024, 0) >= 1) {
                try {
                    $received_text = unmask($buf); //unmask data
                    if($received_text != $null) {
                        $tst_msg = json_decode($received_text); //json decode
                        $user_name = $tst_msg->name; //sender name
                        $user_message = $tst_msg->message; //message text
                        $user_color = $tst_msg->color; //color

                        //prepare data to be sent to client
                        $response_text = mask(json_encode(
                            array('type' => 'user_message', 'name' => $user_name, 'message' => $user_message, 'color' => $user_color)
                        ));
                        send_message($response_text); //send data
                    }
                }
                catch(Exception $ex) {
                    echo "Exception_2=" . $ex->getMessage() . "\n";
                }
                break 2; //exist this loop
            }
        }
        catch(Exception $ex) {
            echo "Exception=" . $ex->getMessage() . "\n";
        }

        $buf = @socket_read($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;
    $end_check = ord($text[0]) & 0x0F;
    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];
    }
    if($end_check == 8) {
        echo "Client Disconnected...\n";
        return null;
    }
    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: $host\r\n" .
        "Sec-WebSocket-Accept:$secAccept\r\n\r\n";
    socket_write($client_conn, $upgrade, strlen($upgrade));
}
?>











Download full example from here
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Saturday, December 10, 2016

Simple Chat Application Using PHP & WebSocket

Below is full server.php script

Download full example from here
