PWA Blog Post - Code snippets (serviceworker.js)

serviceworker.js

// "Install" event handler will be invoked only once when you first time navigate to the page
self.addEventListener('install', function(event) {
 event.waitUntil(
   caches.open('app-cache').then(function(cache) {
     // Adds index.html page to the cache
     return cache.add('index.html');
   })
 );
});

// Will be invoked for every network call: XHR, static resources, etc.
self.addEventListener('fetch', function(event) {
 event.respondWith(
   // For every request checks matching value in the cache
   caches.match(event.request).then(function(response) {
     // Returns cached response; otherwise, makes an actual network call
     return response || fetch(event.request);
   })
 );
});