Book Image

Node Cookbook

By : David Mark Clements
Book Image

Node Cookbook

By: David Mark Clements

Overview of this book

The principles of asynchronous event-driven programming are perfect for today's web, where efficient real-time applications and scalability are at the forefront. Server-side JavaScript has been here since the 90's but Node got it right. With a thriving community and interest from Internet giants, it could be the PHP of tomorrow. "Node Cookbook" shows you how to transfer your JavaScript skills to server side programming. With simple examples and supporting code, "Node Cookbook" talks you through various server side scenarios often saving you time, effort, and trouble by demonstrating best practices and showing you how to avoid security faux pas. Beginning with making your own web server, the practical recipes in this cookbook are designed to smoothly progress you to making full web applications, command line applications, and Node modules. Node Cookbook takes you through interfacing with various database backends such as MySQL, MongoDB and Redis, working with web sockets, and interfacing with network protocols, such as SMTP. Additionally, there are recipes on correctly performing heavy computations, security implementations, writing, your own Node modules and different ways to take your apps live.
Table of Contents (16 chapters)
Node Cookbook
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface

Creating a real-time widget


The configuration options and well thought out methods of socket.io make for a highly versatile library. Let's explore the dexterity of socket.io by making a real-time widget that can be placed on any website and instantly interface with a remote socket.io server to begin providing a constantly updated total of all users currently on site. We'll name it the Live Online Counter (loc for short).

Our widget is for easy user consumption and should require very little knowledge to get working, so we want a very simple interface. Loading our widget through a script tag, and then initializing the widget with a prefabricated init method would be ideal (this allows us to pre-define properties before initialization if necessary).

Getting ready

We'll need to create a new folder with some new files: widget_server.js, widget_client.js, server.js, and index.html.

Before we start let's also get the socket.io-client module from npm. We'll be using this to build our custom socket...