Book Image

MERN Quick Start Guide

By : Eddy Wilson Iriarte Koroliova
3 (1)
Book Image

MERN Quick Start Guide

3 (1)
By: Eddy Wilson Iriarte Koroliova

Overview of this book

The MERN stack is a collection of great tools—MongoDB, Express.js, React, and Node—that provide a strong base for a developer to build easily maintainable web applications. With each of them a JavaScript or JavaScript-based technology, having a shared programming language means it takes less time to develop web applications. This book focuses on providing key tasks that can help you get started, learn, understand, and build full-stack web applications. It walks you through the process of installing all the requirements and project setup to build client-side React web applications, managing synchronous and asynchronous data flows with Redux, and building real-time web applications with Socket.IO, RESTful APIs, and other concepts. This book gives you practical and clear hands-on experience so you can begin building a full-stack MERN web application. Quick Start Guides are focused, shorter titles that provide a faster paced introduction to a technology. They are for people who don't need all the detail at this point in their learning curve. The presentation has been streamlined to concentrate on the things you really need to know.
Table of Contents (8 chapters)

Understanding Redux middleware

Probably the easiest and best way of extending the Redux functionality is by using middleware.

There is a store enhancer function that comes in the Redux library named applyMiddleware and allows you define one or multiple middleware functions. The way middleware works in Redux is simple, it allows you to wrap the dispatch method of the store to extend its functionality. The same way as store enhancer functions, middleware is composable and has the following signature:

middleware = API => next => action => next(action) 

Here, API is an object containing the dispatch and getState methods from the store, destructuring the API, the signature looks like this:

middleware = ({ 
}) => next => action => next(action)  

Let's analyze how it works:

  1. The applyMiddleware function receives one or more middleware...