Book Image

Learning Redux

By : Bugl
Book Image

Learning Redux

By: Bugl

Overview of this book

The book starts with a short introduction to the principles and the ecosystem of Redux, then moves on to show how to implement the basic elements of Redux and put them together. Afterward, you are going to learn how to integrate Redux with other frameworks, such as React and Angular. Along the way, you are going to develop a blog application. To practice developing growing applications with Redux, we are going to start from nothing and keep adding features to our application throughout the book. You are going to learn how to integrate and use Redux DevTools to debug applications, and access external APIs with Redux. You are also going to get acquainted with writing tests for all elements of a Redux application. Furthermore, we are going to cover important concepts in web development, such as routing, user authentication, and communication with a backend server After explaining how to use Redux and how powerful its ecosystem can be, the book teaches you how to make your own abstractions on top of Redux, such as higher-order reducers and middleware. By the end of the book, you are going to be able to develop and maintain Redux applications with ease. In addition to learning about Redux, you are going be familiar with its ecosystem, and learn a lot about JavaScript itself, including best practices and patterns.
Table of Contents (13 chapters)

What is middleware?

Middleware is a JavaScript pattern, similar to the Chain of Responsibility (CoR) pattern, where a chain of functions is used to handle an incoming event, often in the form of a request.

This pattern is especially useful in libraries that deal with events (such as requests in express or actions in Redux). The middleware pattern has several benefits:

  • It allows us to do the following:
    • Use several functions to handle the event and process the data
    • Have functions act as a filter for certain kinds of data
  • It doesn't require explicit knowledge between sender and receiver
  • The chain of functions can be changed during runtime, acting as an event pipeline

Certain libraries, such as express, allow you to extend their functionality using middleware. This is usually done using .use() on the instance (in express, the instance will be the app object). We pass a middleware...