- What's this project?
- What changes were made?
- What additional changes might be needed?
- How can I try out the Progressive Web App?
- How can I report bugs?
What's this project?
What changes were made?
GitHub's visual diff shows all the changes needed to make a Progressive Web App. They include:
Adding in a service worker
sw-precache dependency was added to
package.json, and the
npm run build command has been updated to call the
interface after the
webpack build process is completed.
sw-precache generates a
service-worker.js file that will automatically
cache the other static files in the
build/ directory, and keep them up to
date when you deploy changes.
Code to register the service worker was also added to
The service worker is only generated as part of the production build, so the
development environment will continue to work as before. When running a
production server locally, make sure you use a different port than
ensure the service worker does not inadvertantly take control of the development
Adding in a Web App Manifest
A web app manifest provides metadata about your web app. Along with a service worker, your web app needs a manifest in order to trigger the Add to Homescreen prompt (in supported browsers).
Adding in a GitHub deployment step
While not strictly necessary, a new
npm run gh-pages script was added in,
relying on the
"homepage": "./" property was set in
ensure that relative paths
are used in the generated output. This plays nicely with both GitHub Pages
hosting and should work well with other hosting environments, too.
What additional changes might be needed?
By following the changes made,
you should end up with a Progressive Web App using React that's ready to be
deployed to any static hosting environment. However, if you add in additional
functionality to the starting point, you may need to update your
settings to ensure the service worker behaves properly.
I've added in React Router and now my URLs don't work offline
If you've followed the suggestions in the
and added in React Router using the
History API to manage URLs, then you need to tell the service worker that
navigations to all the random URLs your web app now supports should actually
be fulfilled with the cached copy of your
index.html. You can do this
Assuming you're using the
sw-precache command-line interface, the additional
flag would look like
I'm using cross-origin APIs or resources, and they aren't working while offline
The service worker generated by default by
sw-precache only handles requests
Requests made at runtime for, e.g., APIs or images that live on other servers
won't be handled by the default
sw-precache setup. This means they will stop
sw-toolbox allows you to
set up runtime caching strategies, using URL patterns to determine what
strategy and cache sizes to use.
sw-precache provides an easy way to use
sw-toolbox via the
Because the configuration can get complex, it's best not to attempt to provide
it via a command-line flag. Instead, you can transition to a JSON config file to
set up runtime caching, along with all the other
sw-precache options. This
sample config file
can be used as a starting point, and you'd add in the
--config=sw-precache-config.json flag to your
build script to get
sw-precache to start using that file.
How can I try out the Progressive Web App?
The code from this project is deployed at https://jeffy.info/create-react-pwa/
How can I report bugs?
If you've found a bug in the code output by
create-react-app, please let the
project maintainers know in their issue tracker.
If you've found an issue specific to the Progressive Web App bits (the service worker, the Web App Manifest, etc.), then please let us know in this project's issue tracker.