https://unbywyd.com/sw.js

1/* unbywyd.com — minimal service worker
2 * Strategy:
3 *   - HTML / navigation requests:  network-first, fallback to cache, then offline.html
4 *   - Static assets (images, css, js, fonts, manifest, video): cache-first with background revalidate
5 *   - All other GET: network-first, fallback to cache
6 * Bumping CACHE_VERSION invalidates all old caches on the next visit.
7 */
8
9const CACHE_VERSION = 'v2';
10const STATIC_CACHE  = `unbywyd-static-${CACHE_VERSION}`;
11const RUNTIME_CACHE = `unbywyd-runtime-${CACHE_VERSION}`;
12const OFFLINE_URL  = '/offline.html';
13
14const PRECACHE_URLS = [
15  '/',
16  '/index.html',
17  '/offline.html',
18  '/manifest.webmanifest',
19  '/icon-192.png',
20  '/icon-512.png'
21];
22
23self.addEventListener('install', (event) => {
24  event.waitUntil(
25    caches.open(STATIC_CACHE).then((cache) => cache.addAll(PRECACHE_URLS))
26      .then(() => self.skipWaiting())
27  );
28});
29
30self.addEventListener('activate', (event) => {
31  event.waitUntil(
32    caches.keys().then((keys) => Promise.all(
33      keys.filter((k) => k !== STATIC_CACHE && k !== RUNTIME_CACHE).map((k) => caches.delete(k))
34    )).then(() => self.clients.claim())
35  );
36});
37
38function isStaticAsset(url) {
39  return /\.(?:png|jpg|jpeg|webp|svg|gif|ico|css|js|woff2?|ttf|otf|mp4|webm|json|webmanifest)$/i.test(url.pathname);
40}
41
42self.addEventListener('fetch', (event) => {
43  const req = event.request;
44  if (req.method !== 'GET') return;
45
46  const url = new URL(req.url);
47  const sameOrigin = url.origin === self.location.origin;
48
49  // navigation / HTML — network first, fallback to cache, then offline page
50  if (req.mode === 'navigate' || (req.headers.get('accept') || '').includes('text/html')) {
51    event.respondWith(
52      fetch(req).then((res) => {
53        const copy = res.clone();
54        caches.open(RUNTIME_CACHE).then((c) => c.put(req, copy)).catch(() => {});
55        return res;
56      }).catch(() => caches.match(req).then((cached) => cached || caches.match(OFFLINE_URL)))
57    );
58    return;
59  }
60
61  // static assets — cache first, revalidate in background (stale-while-revalidate)
62  if (isStaticAsset(url) || !sameOrigin) {
63    event.respondWith(
64      caches.match(req).then((cached) => {
65        const fetchPromise = fetch(req).then((res) => {
66          if (res && res.status === 200 && (sameOrigin || res.type === 'cors' || res.type === 'opaque')) {
67            const copy = res.clone();
68            caches.open(RUNTIME_CACHE).then((c) => c.put(req, copy)).catch(() => {});
69          }
70          return res;
71        }).catch(() => cached);
72        return cached || fetchPromise;
73      })
74    );
75    return;
76  }
77
78  // default: network first
79  event.respondWith(
80    fetch(req).then((res) => {
81      const copy = res.clone();
82      caches.open(RUNTIME_CACHE).then((c) => c.put(req, copy)).catch(() => {});
83      return res;
84    }).catch(() => caches.match(req))
85  );
86});
87
88// allow page to trigger immediate activation after a fresh deploy
89self.addEventListener('message', (event) => {
90  if (event.data === 'SKIP_WAITING') self.skipWaiting();
91});