• Socket.io Push Notification Android
• Android Realtime Notification Socket Io Update

You have many options to do this. Here are 3 mainstream, managed services that should be able to scale well depending on your needs. Build Realtime Apps & Take Websockets To The Next Level. Leader in realtime technologies Pusher. Build Realt. In one of my previous posts I wrote about Real time notifications with PHP. I wanted to create a simple comet system fully written in PHP and JavaScript. May 23, 2011  Real time monitoring PHP applications with websockets and node.js (46) Real time notifications (part II). Now with node.js and socket.io (43) Real time notifications with PHP (42) PHP Template Engine Comparison (38) Speed up PHP scripts with asynchronous database queries (32).

If you are making a web application which needs to update client in realtime, you can use this example to quickly write such an application in nodejs using socket.io. Redis pubsub is used as a data source in this example. You can use any other data source.

Since these kind of applications are event-driven on server side (for example, a new message arrived for user) it is a good idea to use nodejs.

Socket.io(http://socket.io) is used to maintain connection with the user. It uses websockets if available else uses fallback machanisms like long-polling. For more details see https://github.com/LearnBoost/socket.io-spec

Requirements

• redis
• nodejs
• nodejs redis module
• nodejs socket.io module

Installation

For installing redis visit http://redis.io/download

For installing nodejs visit http://nodejs.org/download

If you are on linux, you can use package manager of your distribution to install redis and nodejs.

Use npm to install nodejs dependencies

You may want to use hiredis on production as explained on project page https://github.com/mranney/node_redis.

Usage

Start the server by

Now hit http://localhost on your browser

Server side flow

When the server starts, an http handler is created whose only task currently is to server index.html.

There is socket.io handler which listens to all the websocket connections and manages them. It subscribes them to appropricate rooms and sends updates.

Lastly there are two redis clients one of which subscribes to channels on redis and as soon as a message is received, it broadcasts them in appropricate rooms. The second client simply publishes dummy updates to redis channels to which the first redis client is subscribed to.

Socket.io Push Notification Android

Client side flow

As soon as the page load is done, socket.io client tries to connect to the server and on connection sends subscribe message for a particular channel. When updates are received it displays them

Android Realtime Notification Socket Io Update

I have documented the code as extensively as I could. Please email me in case of doubts.