Socket.io, Redis implementation

js-socket-io-redis.js

<script src="https://cdn.socket.io/socket.io-1.3.5.js"></script>
<script>
  
  var socket = io('http://localhost:3000');

  socket.on('test-channel:Test', function(message) {
  	console.log(message); // Object { user : 'danje', status : 'awesome' }
  });
  
</script>

laravel-serverside-example.php

<?php

use Redis;

class Broadcaster {

  public function broadcastRedisEventToSocketIO()
  {
    $connection = Redis::connection('default'); // note that Redis may have to be given a new alias in app/config if php redis module is enabled
    $event = 'Test';
    $payload = json_encode(['event' => $event, 'payload' => ['user' => 'danje', 'status' => 'awesome']]);
    $connection->publish('test-channel', $payload);
  }

}

?>

socket.js

var app = require('express')();
var http = require('http').Server(app);
var io = require('socket.io')(http);
var Redis = require('ioredis');
var redis = new Redis(6379, '192.168.10.10');

redis.subscribe('test-channel', function(err, count) {
	//
});

io.on('connection', function(socket) {
  console.log('a user connected');
});

//io.set('transports',['xhr-polling','jsonp-polling']); apply this if websocket is failing to connect on modern browsers
redis.on('message', function(channel, message) {
	console.log('Message received!');

	message = JSON.parse(message);
	io.emit(channel + ':' + message.event, message.payload);
});

http.listen(3000, function() {
	console.log('Listening on *:3000');
});

The example implementation with the three files runs as-is using Laravel homestead configured to 192.168.10.10 as it comes with Redis out of the box.

Node.JS is required to run the socket.js server file and naturally express, socket.io and ioredis need to be pulled in for the server to work.

Love redis pub/sub. Check out the nchan mod that ships with nginx you can create endpoints that link to sub models it's great. For instance if you had a crypto exchange you can have an endpoint of /btcusd /ethusdt etc works really well and goes through redis so it scales amazing.