chatRedux/frontend/public/service-worker.js

console.log('start')

const CASH = 'ver-1'
const urlsToCash = ['index.html', 'offline.html']

const self = this;

self.addEventListener('install', (e) => {
  console.log('self wait..')
      e.waitUntil(
        caches.open(CASH)
          .then( cache => {
          console.log('open cash', cache)

          return cache.addAll(urlsToCash)
          })
    )
})

self.addEventListener('fetch', (e) => {
    e.respondWith(
        caches.match(e.request)
            .then(() => {
                return fetch(e.request)
                    .catch(() => caches.match('offline.html'))
            })
    )
})


self.addEventListener('activate', (e) => {
    const cacheWersions = [];
    cacheWersions.push(CASH);

    e.waitUntil(
        caches.keys().then(cachNames => Promise.all(
            cachNames.map(cacheName => {
                    if(!cacheWersions.includes(cacheName)){
                        return caches.delete(cacheName);
                    }
                }
            )
        ))
    )

  
})
// /* eslint-disable no-restricted-globals */

// // This service worker can be customized!
// // See https://developers.google.com/web/tools/workbox/modules
// // for the list of available Workbox modules, or add any other
// // code you'd like.
// // You can also remove this file if you'd prefer not to use a
// // service worker, and the Workbox build step will be skipped.

// import { clientsClaim } from 'workbox-core';
// import { ExpirationPlugin } from 'workbox-expiration';
// import { precacheAndRoute, createHandlerBoundToURL } from 'workbox-precaching';
// import { registerRoute } from 'workbox-routing';
// import { StaleWhileRevalidate } from 'workbox-strategies';

// clientsClaim();

// // Precache all of the assets generated by your build process.
// // Their URLs are injected into the manifest variable below.
// // This variable must be present somewhere in your service worker file,
// // even if you decide not to use precaching. See https://cra.link/PWA
// precacheAndRoute(self.__WB_MANIFEST);

// // Set up App Shell-style routing, so that all navigation requests
// // are fulfilled with your index.html shell. Learn more at
// // https://developers.google.com/web/fundamentals/architecture/app-shell
// const fileExtensionRegexp = new RegExp('/[^/?]+\\.[^/]+$');
// registerRoute(
//   // Return false to exempt requests from being fulfilled by index.html.
//   ({ request, url }) => {
//     // If this isn't a navigation, skip.
//     if (request.mode !== 'navigate') {
//       return false;
//     } // If this is a URL that starts with /_, skip.

//     if (url.pathname.startsWith('/_')) {
//       return false;
//     } // If this looks like a URL for a resource, because it contains // a file extension, skip.

//     if (url.pathname.match(fileExtensionRegexp)) {
//       return false;
//     } // Return true to signal that we want to use the handler.

//     return true;
//   },
//   createHandlerBoundToURL(process.env.PUBLIC_URL + '/index.html')
// );

// // An example runtime caching route for requests that aren't handled by the
// // precache, in this case same-origin .png requests like those from in public/
// registerRoute(
//   // Add in any other file extensions or routing criteria as needed.
//   ({ url }) => url.origin === self.location.origin && url.pathname.endsWith('.png'), // Customize this strategy as needed, e.g., by changing to CacheFirst.
//   new StaleWhileRevalidate({
//     cacheName: 'images',
//     plugins: [
//       // Ensure that once this runtime cache reaches a maximum size the
//       // least-recently used images are removed.
//       new ExpirationPlugin({ maxEntries: 50 }),
//     ],
//   })
// );

// // This allows the web app to trigger skipWaiting via
// // registration.waiting.postMessage({type: 'SKIP_WAITING'})
// self.addEventListener('message', (event) => {
//   if (event.data && event.data.type === 'SKIP_WAITING') {
//     self.skipWaiting();
//   }
// });

// Any other custom service worker logic can go here.