Book Image

Socket.IO Cookbook

By : Tyson Cadenhead
Book Image

Socket.IO Cookbook

By: Tyson Cadenhead

Overview of this book

Socket.IO is a JavaScript library that provides you with the ability to implement real-time analytics, binary streaming, instant messaging, and document collaboration. It has two parts: a client-side library that runs in the browser, and a server-side library for node.js. Socket.IO is event-driven and primarily uses the WebSocket protocol that allows us to emit data bi-directionally from the server and the client. Socket.IO This book is a complete resource, covering topics from webSocket security to scaling the server-side of a Socket.IO application and everything in between. This book will provide real-world examples of how secure bi-directional, full-duplex connections that can be created using Socket.IO for different environments. It will also explain how the connection vulnerabilities can be resolved for large numbers of users and huge amounts of data/messages. By the end of the book, you will be a competent Socket.IO developer. With the help of the examples and real-world solutions,you will learn to create fast, scalable, and dynamic real-time apps by creating efficient messaging systems between the server side and the client side using Socket.IO.
Table of Contents (15 chapters)
Socket.IO Cookbook
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Introduction


A single node server can typically handle several thousand simultaneous connections. However, as the audience of an application grows, it is important to make sure that the application is scalable. On the server side, this means that we may want to distribute our applications across multiple threads or node instances.

The issue with distributing your application across nodes is that when we emit a message, it will only be received by one of the distributed servers. Sockets that are not connected to the same server as the one that receives the message will not be able to receive it without some additional handling. Luckily, there are some great ways to pass session data between servers with a caching system, such as Redis, Memcache, or RabbitMQ. By using adapters for one of these distributed caching mechanisms, we can easily scale our servers without compromising our Socket.IO connections.