=======================================
PHP websockets
=======================================

A quick introduction to test php sockets.

1. create and run listener on the command line.
2. telnet to the socket and type something.


=======================================
ed /non/web/directory/socket.php
---------------------------------------

<?php
error_reporting(E_ALL);

if(php_sapi_name() != 'cli') {
  print('nope');
  exit();
}

set_time_limit(0);

ob_implicit_flush();

$address =  '0.0.0.0';//'192.168.99.100';//'127.0.0.1';//'66.77.88.99';
$port = 8080;
$reuse = 1;
$backlog = 5;

$socket = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
if($socket === false) {
  print('socket_create() failed reason: '.socket_strerror(socket_last_error()).PHP_EOL);
} else {
  // Set the SO_REUSEADDR option
  if(socket_set_option($socket, SOL_SOCKET, SO_REUSEADDR, $reuse) === false) {
    print('socket_set_option() failed reason: '.socket_strerror(socket_last_error($socket)).PHP_EOL);
  } else {
    // Bind the socket to an address and port
    if(socket_bind($socket, $address, $port) === false) {
      print('socket_bind() failed reason: '.socket_strerror(socket_last_error($socket)).PHP_EOL);
    } else {
      if(socket_listen($socket, $backlog) === false) {
        print('socket_listen() failed: reason: '.socket_strerror(socket_last_error($socket)).PHP_EOL);
      } else {
        // Continue with your server setup
        print('Socket bound successfully to port '.$port.PHP_EOL);
      }
    }
  }
}

// clients array
$clients = array();

while(true) {
  $read = array();
  $read[] = $socket;
  $read = array_merge($read, $clients);

  // Set up a blocking call to socket_select
  $write = NULL;
  $except = NULL;
  $tv_sec = 5;
  if(socket_select($read, $write, $excep, $tv_sec) < 1) {
    // SocketServer::debug('Problem blocking socket_select?');
    continue;
  }

  // new connections
  if(in_array($socket, $read)) {
    if(($msgsock = socket_accept($socket)) === false) {
      print('socket_accept() failed: reason: '.socket_strerror(socket_last_error($socket)).PHP_EOL);
      break;
    }
    $clients[] = $msgsock;
    $key = array_keys($clients, $msgsock);
    // instructions
    $msg = PHP_EOL.
      'Welcome to the PHP Test Server.'.PHP_EOL.
      'You are customer number: '.$key[0].PHP_EOL.
      'To quit, type "quit". To shut down the server type "shutdown"'.PHP_EOL;
    socket_write($msgsock, $msg, strlen($msg));
  }

  foreach($clients as $key => $client) { // read input for each client
    if(in_array($client, $read)) {
      if(false === ($buf = socket_read($client, 2048, PHP_BINARY_READ))) {
        print('socket_read() failed: reason: '.socket_strerror(socket_last_error($client)).PHP_EOL);
        break 2;
      }
      if(!$buf = trim($buf)) {
        continue;
      }
      if($buf == 'quit') {
        unset($clients[$key]);
        socket_close($client);
        break;
      }
      if($buf == 'shutdown') {
        socket_close($client);
        break 2;
      }
      // some feedback on the client side
      $talkback = 'You '.$key.' said: '.$buf.PHP_EOL;
      socket_write($client, $talkback, strlen($talkback));
      // some feedback on the server side
      print('Client '.$key.' said: '.$buf.PHP_EOL);
    }

  }
}

socket_close($socket);
?>


=======================================
Start the listener on the server
---------------------------------------

root@server:~ # php /non/web/directory/socket.php


=======================================
Connect to the listener
---------------------------------------

user@client:~ # telnet 192.168.99.100 8080

Trying 192.168.99.100...
Connected to 192.168.99.100.
Escape character is '^]'.

Welcome to the PHP Test Server.
You are customer number: 0
To quit, type "quit". To shut down the server type "shutdown"

hello world!

=======================================
done
=======================================