const cacheName = self.location.pathname const pages = [ ]; self.addEventListener("install", function (event) { self.skipWaiting(); caches.open(cacheName).then((cache) => { return cache.addAll(pages); }); }); self.addEventListener("fetch", (event) => { const request = event.request; if (request.method !== "GET") { return; } /** * @param {Response} response * @returns {Promise} */ function saveToCache(response) { if (cacheable(response)) { return caches .open(cacheName) .then((cache) => cache.put(request, response.clone())) .then(() => response); } else { return response; } } /** * @param {Error} error */ function serveFromCache(error) { return caches.open(cacheName).then((cache) => cache.match(request.url)); } /** * @param {Response} response * @returns {Boolean} */ function cacheable(response) { return response.type === "basic" && response.ok && !response.headers.has("Content-Disposition") } event.respondWith(fetch(request).then(saveToCache).catch(serveFromCache)); });