clientsclaim9

sw.js

self.addEventListener('install', event => {
  // cache a cat SVG
  event.waitUntil(
    caches.open('static-v1')
    	.then(cache => cache.add('cat.svg'))
  );
});

self.addEventListener('activate', event => {
  clients.claim();
  console.log('Now controlling the page!');
});

self.addEventListener('fetch', event => {
  if (url.pathname.endsWith('/dog.svg')) {
    event.respondWith(caches.match('cat.svg'));
  }
});