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

Joining rooms


In addition to namespaces, we can also use rooms in Socket.IO to ensure that our messages are only being delivered to the correct sockets.

Although each socket can only have a single namespace, these sockets can belong to multiple rooms. You can think of rooms as channels that a socket subscribes to in order to receive specific types of messages.

For example, if we built a programming application, the user may be interested in JavaScript and Node messages, but not Ruby or C#. With rooms, we can allow users to send messages to specific channels so that only the interested parties will receive it.

As rooms can only be joined if we know the name of the room, it creates a sort of sudo-security. But it is a bit of a hack because if someone can guess the room name and it is exposed to the client to join, they can join any arbitrary room.

In this recipe, we will demonstrate how a user can join a room.

Getting ready

In this recipe, we will use jQuery for some simple DOM manipulation.

How...