#Ratchet

A PHP 5.3 (PSR-0 compliant) component library for serving sockets and building socket based applications. Build up your application through simple interfaces using the decorator and command patterns. Re-use your application without changing any of its code just by combining different components. Ratchet's primary intention is to be used as a WebSocket server.

##WebSockets

• Supports the RFC6455, HyBi-10, and Hixie76 protocol versions (at the same time)
• Tested on Chrome 18 - 16, Firefox 6 - 8, Safari 5, iOS 4.2, iOS 5

##Requirements

Shell access is required and a dedicated machine with root access is recommended. To avoid proxy/firewall blockage it's recommended WebSockets are run on port 80, which requires root access. Note that you can not run two applications (Apache and Ratchet) on the same port, thus the requirement for a separate machine (for now).

Cookies from your domain will be passed to the socket server, allowing you to identify users. Accessing your website's session data in Ratchet is a feature in the works.

See https://github.com/cboden/Ratchet-examples for some out-of-the-box working demos using Ratchet.

###Future considerations

Ideally, soon, web servers will start supporting WebSockets to some capacity and PHP will no longer need to run its self from the command line. In theory, the server (like Nginx) would recognize the HTTP handshake request to upgrade the protocol to WebSockets and run/pass data through to a user configured PHP file. When this happens, you can keep your script the same, just remove the IOServerComponent wrapper and maybe eventually the WebSocketComponent wrapper if the servers recognize the protocol message framing.

---

###A quick server example

<?php
namespace MyApps;
use Ratchet\Component\MessageComponentInterface;
use Ratchet\Resource\ConnectionInterface;
use Ratchet\Component\Server\IOServerComponent;
use Ratchet\Component\WebSocket\WebSocketComponent;
use Ratchet\Resource\Command\Composite as Cmds;
use Ratchet\Resource\Command\Action\SendMessage;
use Ratchet\Resource\Command\Action\CloseConnection;

/**
 * chat.php
 * Send any incoming messages to all connected clients (except sender)
 */
class Chat implements MessageComponentInterface {
    protected $_clients;

    public function __construct(MessageComponentInterface $app = null) {
        $this->_clients = new \SplObjectStorage;
    }

    public function onOpen(ConnectionInterface $conn) {
        $this->_clients->attach($conn);
    }

    public function onMessage(ConnectionInterface $from, $msg) {
        $commands = new Cmds;

        foreach ($this->_clients as $client) {
            if ($from != $client) {
                $msg_cmd = new SendMessage($client);
                $msg_cmd->setMessage($msg);

                $commands->enqueue($msg_cmd);
            }
        }

        return $commands;
    }

    public function onClose(ConnectionInterface $conn) {
        $this->_clients->detach($conn);
    }

    public function onError(ConnectionInterface $conn, \Exception $e) {
        return new CloseConnection($conn);
    }
}

    // Run the server application through the WebSocket protocol
    $server = new IOServerComponent(new WebSocketComponent(new Chat));
    $server->run(80);

# php chat.php