notes

1.6 KB

1. // sw.js — the service worker of notes.worldapi.org (ticket notes#2): the app opens without a network.
2. // NETWORK FIRST: every page and asset is fetched as usual and the answer is kept; with no network the kept copy
3. // answers. A page (`/` or `/note/<id>`) is kept once, under '/shell': the page carries no note data (the notes come
4. // from the browser's IndexedDB, /notes-offline.js), so one page serves every note. The API and the socket are never
5. // touched here. /notes-offline.js also puts the page and the assets it was loaded with into the same cache.
6. const CACHE = 'notes-shell-v1';
7. const isPage = (url) => url.pathname === '/' || url.pathname.startsWith('/note/');
9. self.addEventListener('install', () => self.skipWaiting());
10. self.addEventListener('activate', (e) => e.waitUntil((async () => {
11. for (const k of await caches.keys()) if (k !== CACHE) await caches.delete(k);
12. await self.clients.claim();
13. })()));
15. self.addEventListener('fetch', (e) => {
16. const req = e.request;
17. const url = new URL(req.url);
18. if (req.method !== 'GET' || url.origin !== self.location.origin) return;
19. if (url.pathname.startsWith('/api/') || url.pathname.startsWith('/login/')) return;
20. if (req.mode === 'navigate' && !isPage(url)) return;
21. e.respondWith((async () => {
22. const cache = await caches.open(CACHE);
23. const key = req.mode === 'navigate' ? '/shell' : req.url;
24. try {
25. const res = await fetch(req);
26. if (res.ok && !res.redirected && res.type === 'basic') cache.put(key, res.clone());
27. return res;
28. } catch (err) {
29. const kept = await cache.match(key);
30. if (kept) return kept;
31. throw err;
32. }
33. })());
34. });