Book Image

Mastering Reactive JavaScript

By : Erich de Souza Oliveira
Book Image

Mastering Reactive JavaScript

By: Erich de Souza Oliveira

Overview of this book

If you’re struggling to handle a large amount of data and don’t know how to improve your code readability, then reactive programming is the right solution for you. It lets you describe how your code behaves when changes happen and makes it easier to deal with real-time data. This book will teach you what reactive programming is, and how you can use it to write better applications. The book starts with the basics of reactive programming, what Reactive Extensions is, and how can you use it in JavaScript along with some reactive code using Bacon. Next, you’ll discover what an Observable and an Observer are and when to use them.You'll also find out how you can query data through operators, and how to use schedulers to react to changes. Moving on, you’ll explore the RxJs API, be introduced to the problem of data traffic (backpressure), and see how you can mitigate it. You’ll also learn about other important operators that can help improve your code readability, and you’ll see how to use transducers to compose operators. At the end of the book, you’ll get hands-on experience of using RxJs, and will create a real-time web chat using RxJs on the client and server, providing you with the complete package to master RxJs.
Table of Contents (11 chapters)

Scaling the server

Currently our implementation cannot be used if we decide to deploy several servers. Imagine the scenario where user A connects to server A, and user B connects to server B; user A and user B cannot chat, because they are on different servers.

To make users connected from different servers communicate, we need to find a way to make our server communicate, and we can do this using the Redis database. Among other amazing features, Redis supports what is called a publish/subscriber pattern. With this pattern, a server can publish a message, and all servers subscribed to listen to that message will receive it.

With this feature Redis is the perfect database to solve our problem of server communication, so let's see how we can connect to it to receive messages and also how we can change our data store to support it.

Connecting to Redis

To use Redis database we need a library to connect to it, the most common library for node is called ioredis. This library is available on npm and...