sw.js

"use strict";

const APP_CACHE = "berzanjs-app-cache-v1.2.6";
const CONTENT_CACHE = "berzanjs-schedule-cache-v1";
const URLS_TO_CACHE = [
	"/",
	"/css/style.css",
	"/js/index.js",
	"/js/settings.js",
	"/js/utils.js",
	"/views/neoschedule.html",
	"/views/etc.html",
	"/views/settings.html",
	"/views/about.html",
	"/manifest.json",
	"/img/logo/logo-512.png",
	"https://cdnjs.cloudflare.com/ajax/libs/slideout/1.0.1/slideout.js"
];

let refreshing = false;

self.addEventListener("install", function(evnt) {
	skipWaiting();

	evnt.waitUntil(
		caches.open(APP_CACHE)
			.then(function(cache) {
				console.log("Opened cache");
				return cache.addAll(URLS_TO_CACHE);
			})
	);
});

self.addEventListener("activate", function(evnt) {
	const CACHE_WHITELIST = [
		APP_CACHE,
		CONTENT_CACHE
	];

	evnt.waitUntil(
		caches.keys().then(cacheNames => {
			return Promise.all(
				cacheNames.map(cacheName => {
					if (CACHE_WHITELIST.indexOf(cacheName) === -1) {
						return caches.delete(cacheName);
					}
				})
			);
		})
	);
});

self.addEventListener("fetch", function(evnt){
	evnt.respondWith(
		caches.match(evnt.request)
			.then(function(response) {
				if (response) {
					// TODO: refresh caches
					/*
					if (response.type === "cors" && evnt.clientId) {
						refreshCacheEntry(evnt.request, evnt.clientId);
					}

					 */
					return response;
				}
				return fetch(evnt.request).then(
					function(response) {
						if (
							!response ||
							response.status !== 200 ||
							response.type !== "basic"
						) {
							return response;
						}

						const RESPONSE_TO_CACHE = response.clone();

						let cacheType;
						if (response.type === "cors") {
							cacheType = CONTENT_CACHE;
						} else {
							cacheType = APP_CACHE;
						}

						caches.open(cacheType)
							.then(function(cache) {
								cache.put(evnt.request, RESPONSE_TO_CACHE);
							});

						return response;
					}
				);
			})
	);
});

self.addEventListener("controllerchange", () => {
	if (refreshing) {
		return; // Prevent infinite refresh loops
	}

	refreshing = true;

	window.location.reload();
});

async function refreshCacheEntry(request, clientID) {
	fetch(request)
		.then(async response => {

			const client = await self.clients.get(clientID);

			client.postMessage({
				URL: request.url,
				response: response
			});
			//caches.match(request)
		})
}