socket.io-hub

Scalable Socket.IO

Installation

npm install https://github.com/teambition/socket.io-hub

Overview

Socket.io is a great middleware to build in-time applications, but it only can run in a single process. So we write this wrapper to support multiprocess applications.

Every node process will create two redis instance and we use redis pub/sub for message exchange.

When socket.io emit an event, we publish data of this event to redis and other processes will catch this event and emit to their own clients.

Events:

• broadcast.emit
• in(room).emit
• of(/namespace).emit

Usage

Usually we create a simple http server and add socket.io support:

socketIo = require('socket.io')
http = require('http')
server = http.createServer (req, res) ->
  res.end('Hello, world!')
io = socketIo.listen(server)
io.sockets.on 'connection', (socket) ->
  socket.emit('news', "new coming")
  socket.on 'chat', (data) ->
    console.log data
server.listen(3000)
console.log "server listen on 3000"

To use socket.io-hub, all we need is add two line on the above code:

socketIo = require('socket.io-hub')  # replace socket.io with socket.io-hub
http = require('http')
server = http.createServer (req, res) ->
  res.end('Hello, world!')
io = socketIo.hub({adapter: 'redis'}).listen(server)  # add hub adapter, for this moment it only supports redis
io.sockets.on 'connection', (socket) ->
  socket.subscribe()  # add subscribe to emit events from redis
  socket.emit('news', "new coming")
  socket.on 'chat', (data) ->
    console.log data
server.listen(3000)
console.log "server listen on 3000"

Done!

License

MIT