Book Image

Getting Started with React

By : Doel Sengupta, Manu Singhal, Danillo Corvalan
Book Image

Getting Started with React

By: Doel Sengupta, Manu Singhal, Danillo Corvalan

Overview of this book

ReactJS, popularly known as the V (view) of the MVC architecture, was developed by the Facebook and Instagram developers. It follows a unidirectional data flow, virtual DOM, and DOM difference that are generously leveraged in order to increase the performance of the UI. Getting Started with React will help you implement the Reactive paradigm to build stateless and asynchronous apps with React. We will begin with an overview of ReactJS and its evolution over the years, followed by building a simple React component. We will then build the same react component with JSX syntax to demystify its usage. You will see how to configure the Facebook Graph API, get your likes list, and render it using React. Following this, we will break the UI into components and you’ll learn how to establish communication between them and respond to users input/events in order to have the UI reflect their state. You’ll also get to grips with the ES6 syntaxes. Moving ahead, we will delve into the FLUX and its architecture, which is used to build client-side web applications and complements React’s composable view components by utilizing a unidirectional data flow. Towards the end, you’ll find out how to make your components reusable, and test and deploy them into a production environment. Finally, we’ll briefly touch on other topics such as React on the server side, Redux and some advanced concepts.
Table of Contents (18 chapters)
Getting Started with React
About the Authors
About the Reviewers

Testing with shallow rendering

Shallow rendering is a method used while testing React components in which the component is "one level deep". Such a shallow-rendered test component has the facts regarding the returned things with respect to the render methods. Such components do not have the child components attached to it, and it does not require DOM.

Thus, while testing with a shallow rendering method, it should be remembered that any changes in the parent component that has the DOM changes and/or any child components been changed may require in rewriting the test.

Let's explore this with help of some code. In the following example, we will be creating a React component (GreetingComponent) where the render method will return a div with two children (h2 and span elements).

The code of greeting.js:

// greeting.js

import React from 'react';

const { div, h2, span} = React.DOM;

export default React.createClass({

  displayName: 'GreetingComponent',