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)


Promises came about as a response to the callback hell problem described in the previous section. They have quite a long history, stretching back to the early 80s, when the legendary Barbara Liskov coined the term Promise. The idea of a Promise is to flatten out async code. A promise is said to have the following states:

  • Pending: This means it has not yet been decided or that the data is not available yet
  • Fulfilled: The data has come back
  • Rejected: An error happened during the operation


Something important to know is that a Promise returns straight away, but the result is not available straight away. Promises are also known as thenables, because you need to register a callback with its then() method once...