Book Image

Architecting Angular Applications with Redux, RxJS, and NgRx

By : Christoffer Noring
Book Image

Architecting Angular Applications with Redux, RxJS, and NgRx

By: Christoffer Noring

Overview of this book

Managing the state of large-scale web applications is a highly challenging task with the need to align different components, backends, and web workers harmoniously. When it comes to Angular, you can use NgRx, which combines the simplicity of Redux with the reactive programming power of RxJS to build your application architecture, making your code elegant and easy to reason about, debug, and test. In this book, we start by looking at the different ways of architecting Angular applications and some of the patterns that are involved in it. This will be followed by a discussion on one-way data flow, the Flux pattern, and the origin of Redux. The book introduces you to declarative programming or, more precisely, functional programming and talks about its advantages. We then move on to the reactive programming paradigm. Reactive programming is a concept heavily used in Angular and is at the core of NgRx. Later, we look at RxJS, as a library and master it. We thoroughly describe how Redux works and how to implement it from scratch. The two last chapters of the book cover everything NgRx has to offer in terms of core functionality and supporting libraries, including how to build a micro implementation of NgRx. This book will empower you to not only use Redux and NgRx to the fullest, but also feel confident in building your own version, should you need it.
Table of Contents (12 chapters)

The callback pattern

Previously, we described what asynchronous and synchronous code looks like when you encounter it in your everyday life as a developer. What might be of interest is to know how an operating system looks at such code and how it deals with it. An operating system deals with asynchronous code by thinking of it in terms of the following concepts:

  • Events, these are messages that signals to the operating system that a certain type of action has occurred
  • Event handler, this is the piece of code that should run when an event has occurred
  • Event queue, this is where all events and their event handlers are placed, waiting to be executed

Let's illustrate this flow in the following diagram:

What we can see in the preceding image is how events are being picked from an event queue. Here, the CLICK event is being run when a Dispatcher tells it to and its corresponding...