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)

Dealing with asynchronous calls

Dispatching actions is always done synchronously. Data is fetched through AJAX asynchronously, so how do we get asynchronous to play well with Redux?

You should define your Redux states in the following way when setting up an asynchronous call:

  • Loading: Here, we have the chance to show a spinner, not render part of the UI, or convey to the user in some other way that the UI is waiting for something
  • Data successfully fetched: You should set a state for the fetched data
  • Error happened: You should record the error somehow so that you are able to tell the user that an error occurred

You, by convention, use the word fetch to indicate that you are fetching data. Let's look at an example of what that might look like. First off, let's start by defining the steps we need to take:

  1. Create a reducer. This should have the ability to set different...