Progressive Web Apps with React

Grab the list of cache names

Again, we have to do an event.waitUntil() while we complete this async code. This means we'll have to eventually return a Promise to the event.waitUntil(), which will affect how we write our code.

First, we grab the list of cache keys, by calling cache.keys(), which returns a promise:

self.addEventListener('activate', event => { event.waitUntil(   cache.keys().then(keyList => {   }) );});