Book Image

Progressive Web Apps with React

By : Scott Domes
Book Image

Progressive Web Apps with React

By: Scott Domes

Overview of this book

For years, the speed and power of web apps has lagged behind native applications. Progressive Web Apps (PWAs) aim to solve this by bridging the gap between the web apps and native apps, delivering a host of exciting features. Simultaneously, React is fast becoming the go-to solution for building modern web UIs, combining ease of development with performance and capability. Using React alongside PWA technology will make it easy for you to build a fast, beautiful, and functional web app. After an introduction and brief overview of the goals of PWAs, the book moves on to setting up the application structure. From there, it covers the Webpack build process and the process of creating React components. You'll learn how to set up the backend database and authentication solution to communicate with Firebase and how to work with React Router. Next, you will create and configure your web app manifest, making your PWA installable on mobile devices. Then you'll get introduced to service workers and see how they work as we configure the app to send push notifications using Firebase Cloud Messaging. We'll also explore the App Shell pattern, a key concept in PWAs and look at its advantages regarding efficient performance. Finally, you'll learn how to add of?ine capabilities to the app with caching and confirm your progress by auditing your PWA with Lighthouse. Also, you'll discover helper libraries and shortcuts that will help you save time and understand the future of PWA development.
Table of Contents (21 chapters)
Title Page
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

What is code splitting?


Code splitting is the act of splitting up our JavaScript file into meaningful chunks in order to improve performance, but why do we need it?

Well, when a user first accesses our application, we only need the JavaScript for the route they're currently on.

This means when they're on /login, we only need LoginContainer.js and its dependencies. We don't need UserContainer.js, so we want to immediately load LoginContainer.js and lazy-load UserContainer.js. However, our current Webpack setup creates a single bundle.js file. All our JavaScript is tied together and must be loaded together. Code splitting is a way to fix that. Instead of a single monolithic JavaScript file, we get multiple JavaScript files, one for each route.

So, we'll get one bundle for /login, one for /user/:id, and one for /. Additionally, we’ll get another main bundle with all the dependencies.

Whatever route the user visits first, they'll get the bundle for that route and the main bundle. In the background...