Book Image

Progressive Web Application Development by Example

By : Chris Love
Book Image

Progressive Web Application Development by Example

By: Chris Love

Overview of this book

Are you a developer that wants to create truly cross-platform user experiences with a minimal footprint, free of store restrictions and features customers want? Then you need to get to grips with Progressive Web Applications (PWAs), a perfect amalgamation of web and mobile applications with a blazing-fast response time. Progressive Web Application Development by Example helps you explore concepts of the PWA development by enabling you to develop three projects, starting with a 2048 game. In this game, you will review parts of a web manifest file and understand how a browser uses properties to define the home screen experience. You will then move on to learning how to develop and use a podcast client and be introduced to service workers. The application will demonstrate how service workers are registered and updated. In addition to this, you will review a caching API so that you have a firm understanding of how to use the cache within a service worker, and you'll discover core caching strategies and how to code them within a service worker. Finally, you will study how to build a tickets application, wherein you’ll apply advanced service worker techniques, such as cache invalidation. Also, you'll learn about tools you can use to validate your applications and scaffold them for quality and consistency. By the end of the book, you will have walked through browser developer tools, node modules, and online tools for creating high-quality PWAs.
Table of Contents (12 chapters)

Service worker updates

Updating the service worker file can be a tricky concept as well. There are several factors that determine when your service worker is updated. The update cycle does not start until the browser determines that there is a new service worker file available.

Once a service worker is registered, the browser treats the file like any other file when determining if there is a new version available. It makes a request to the server, which triggers a well-known cycle.

First, there is the local browser cache (not the service worker cache) for the file. If there is a local version available that has not become stale, it is retrieved. Next, the request is sent across the network to the server. If the server responds with a 304, it means that the browser has the most current version. If the file has not changed, then the service worker update cycle does not start. If...