PW_4_YDM.js

// Code for website
// This is the "Offline page" service worker

//Add this below content to your HTML page, or add the js file to your page at the very top to register service worker
if (navigator.serviceWorker.controller) {
  console.log('[PWA Builder] active service worker found, no need to register')
} else {
  //Register the ServiceWorker
  navigator.serviceWorker.register('pwabuider-sw.js', {
    scope: './'
  }).then(function(reg) {
    console.log('Service worker has been registered for scope:'+ reg.scope);
  });
}


// Service worker code
//This is the "Offline page" service worker

//Install stage sets up the offline page in the cache and opens a new cache
self.addEventListener('install', function(event) {
  var offlinePage = new Request('offline.html');
  event.waitUntil(
    fetch(offlinePage).then(function(response) {
      return caches.open('pwabuilder-offline').then(function(cache) {
        console.log('[PWA Builder] Cached offline page during Install'+ response.url);
        return cache.put(offlinePage, response);
      });
  }));
});

//If any fetch fails, it will show the offline page.
//Maybe this should be limited to HTML documents?
self.addEventListener('fetch', function(event) {
  event.respondWith(
    fetch(event.request).catch(function(error) {
      console.error( '[PWA Builder] Network request Failed. Serving offline page ' + error );
      return caches.open('pwabuilder-offline').then(function(cache) {
        return cache.match('offline.html');
      });
    }
  ));
});

//This is a event that can be fired from your page to tell the SW to update the offline page
self.addEventListener('refreshOffline', function(response) {
  return caches.open('pwabuilder-offline').then(function(cache) {
    console.log('[PWA Builder] Offline page updated from refreshOffline event: '+ response.url);
    return cache.put(offlinePage, response);
  });
});