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)

Chapter 2. Reacting for the First Time

In the previous chapter, you started understanding the motivations behind using functional reactive programming in your systems; you also saw how a program using this paradigm fared against a program without it. You learned how reactive programming can improve code readability and testability by decoupling your event sources from the action you take when the action occurs.

We started with some basic examples using bacon.js as the reactive programming library for JavaScript. In the examples, we began with creating our first EventStream from an interval. Then we started using some operators (map() and take()). Finally, we subscribed to this event source to take actions in the case of an event occurrence. This was just a kind introduction to functional reactive programming.

When reading most of the functional reactive programming libraries (for any language), you will see a lot of diagrams explaining how the operator works. In the previous chapter, I presented...