PWA and offline capabilities

Workbox service worker generated into website/public/sw.js. Related: Frontend, Pyodide.

After the first production visit you can generate a timetable, open a cached schedule, and run Pyodide if the WASM files are in pyodide-cache.

website/next.config.ts wraps Next with @ducanh2912/next-pwa:

flowchart TB
  nextConfig[next.config.ts withPWA] --> Build[next build]
  Build --> SW[website/public/sw.js]
  Build --> WB[website/public/workbox-*.js]
  SW --> Precache
  SW --> NF[NetworkFirst /]
  SW --> CF[CacheFirst pyodide CDN]

Manifest: website/public/manifest.json. Name “JIIT Time Table Website”, standalone, theme #F0BB78, background #131010, icons from icon.png. Layout metadata points manifest at /manifest.json.

Build writes a hashed list into sw.js. Typical entries:

The live parser is the wheel under /parser/. If a new build does not list the wheel, first offline generation still needs a prior network fetch of that file.

flowchart TD
  Req[fetch] --> Match{route}
  Match -->|/ | NF[NetworkFirst start-url]
  Match -->|jsdelivr pyodide v0.27.0| CF[CacheFirst pyodide-cache 1y, 10 entries]
  Match -->|precache URL| PC[precacheAndRoute]

NetworkFirst on / prefers a live document, then start-url. Opaque redirects are rewritten to status 200.

CacheFirst for ^https://cdn.jsdelivr.net/pyodide/v0.27.0/full/.* is set in workboxOptions.runtimeCaching. Statuses 0 and 200 are stored.

cleanupOutdatedCaches() drops old precache generations. skipWaiting + clientsClaim activate the new worker immediately.

stateDiagram-v2
  [*] --> Installing
  Installing --> Waiting
  Waiting --> Activating: skipWaiting
  Activating --> Active: clientsClaim

Disabled in next dev. Test offline against a production build.

Install from the browser using the manifest. appleWebApp metadata is set on the root layout.