Book Image

Architecting Angular Applications with Redux, RxJS, and NgRx

Book Image

Architecting Angular Applications with Redux, RxJS, and NgRx

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)

Thinking in streams

So far, we have gone through a bunch of scenarios that have shown us which operators are at our disposal and how they can be chained. We have also seen how operators such as flatMap() and switchMap() can really change things as we move from one type of observable to another. So, which approach should you take when working with Observables? Obviously, we need to express an algorithm using operators, but where do we start? The first thing we need to do is to think of the start and the end. Which types of events do we want to capture and what should the end result look like? That already gives us a hint as to the number of transformations we need to carry out to get there. If we want to transform the data only, then we can probably make do with a map() operator and a filter() operator. If we want to transform from one Observable to the next, then we need a flatMap...