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
About the Author
About the Reviewer
Customer Feedback

Chapter 12. Ready to Cache

We've made enormous strides in the performance of our application. Our JavaScript is now split into smaller chunks based on the routes of our application, and we've deferred loading the less important bits until our app has some idle time. We've also introduced progressive enhancement to show our users content as soon as possible, and learned a lot about how to analyze our app's performance according to RAIL metrics.

However, there remains one central, core inefficiency in our web application. If our user leaves our page to go elsewhere (I know, how dare they) and then returns, we repeat the same process all over again: download the index.html, download the different JavaScript bundles, download the images, and so on.

We're asking our user to download the exact same files, over and over and over, every time they visit the page. Their device has more than enough memory to store those files for us. Why don't we just save them to the user's device, and then retrieve...