JezK

Edit File: sw.js

const preLoad = function () { return caches.open("offline").then(function (cache) { // caching index and important routes return cache.addAll(filesToCache); }); }; self.addEventListener("install", function (event) { event.waitUntil(preLoad()); }); const filesToCache = [ '/', '/offline.html' ]; const checkResponse = function (request) { return new Promise(function (fulfill, reject) { fetch(request).then(function (response) { if (response.status !== 404) { fulfill(response); } else { reject(); } }, reject); }); }; const addToCache = function (request) { return caches.open("offline").then(function (cache) { return fetch(request).then(function (response) { return cache.put(request, response); }); }); }; const returnFromCache = function (request) { return caches.open("offline").then(function (cache) { return cache.match(request).then(function (matching) { if (!matching || matching.status === 404) { return cache.match("offline.html"); } else { return matching; } }); }); }; self.addEventListener("fetch", function (event) { event.respondWith(checkResponse(event.request).catch(function () { return returnFromCache(event.request); })); if(!event.request.url.startsWith('http')){ event.waitUntil(addToCache(event.request)); } });