WebSockets with Ratchet and Symfony

Richard Melo

@allucardster

About me

• System Engineer
• 8+ years experience
• Fullstack Developer
• SUDO co-founder

Agenda

• Intro to WebSockets
• Ratchet PHP
• Ratchet and Symfony
• Demo

What is a WebSocket?

In a nutshell

• Supported major Web browsers
• Low latency
• Bidirectional communication 
• Uses a single TCP connection

WebSockets Pros:

• Cross origin communication
• Cross platform compatibility (desktop, mobile)
• Any message structure is supported

WebSockets Cons:

• Firewalls and proxies
• Security
• Monitoring
• Scaling and load balancing

Ratchet PHP

In a nutshell

• Architecture based in components
• Allow implement WebSocket server
• Allow implement WebSocket handler

<?php

namespace MyApp;

use Ratchet\MessageComponentInterface;
use Ratchet\ConnectionInterface;

class Chat implements MessageComponentInterface {
    public function onOpen(ConnectionInterface $conn)
    {
        //...
    }

    public function onMessage(ConnectionInterface $from, $msg)
    {
        //...
    }

    public function onClose(ConnectionInterface $conn)
    {
        //...
    }

    public function onError(ConnectionInterface $conn, \Exception $e)
    {
        //...
    }
}

WebSocket handler

<?php

use Ratchet\Server\IoServer;
use Ratchet\Http\HttpServer;
use Ratchet\WebSocket\WsServer;
use MyApp\Chat;

require dirname(__DIR__) . '/vendor/autoload.php';

$server = IoServer::factory(
    new HttpServer(
        new WsServer(        
            new Chat() // WebSocket handler instance
        )
    ),
    8080
);

$server->run();

Server

var conn = new WebSocket('ws://localhost:8080');
conn.onopen = function(e) {
    console.log("Connection established!");
};

conn.onmessage = function(e) {
    console.log(e.data);
};

JS Client

Ratchet and Symfony 

• Implement WebSocket server
• Handle multiple topics
• Integrate web app security
• Allow write in WebSocket programmatically

Gos WebSocket Bundle

In a nutshell

• PHP WebSocket server
• PHP WebSocket client
• JS WebSocket client
• Integrates routing
• Integrates security through websocket

Demo

https://github.com/allucardster/ws-xample

Thank you!

• https://en.wikipedia.org/wiki/WebSocket
• http://socketo.me/
• https://github.com/GeniusesOfSymfony/WebSocketBundle
• https://www.pubnub.com/blog/2013-09-11-what-are-websockets/
• https://medium.com/@smartgamma/real-time-web-applications-with-php-and-ratchet-7b039fda2dbd
• https://blog.samuelattard.com/the-tutorial-for-php-websockets-that-i-wish-had-existed/

References