static/service-worker.js

const CACHE_NAME = "cert-study-static-v1";
const STATIC_ASSETS = [
  "/app/static/manifest.webmanifest",
  "/app/static/icons/icon.svg",
  "/app/static/icons/icon-maskable.svg",
  "/app/static/icons/icon-192.png",
  "/app/static/icons/icon-512.png",
  "/app/static/icons/icon-maskable-192.png",
  "/app/static/icons/icon-maskable-512.png"
];

self.addEventListener("install", (event) => {
  event.waitUntil(
    caches.open(CACHE_NAME).then((cache) => cache.addAll(STATIC_ASSETS))
  );
  self.skipWaiting();
});

self.addEventListener("activate", (event) => {
  event.waitUntil(
    caches
      .keys()
      .then((keys) =>
        Promise.all(keys.filter((key) => key !== CACHE_NAME).map((key) => caches.delete(key)))
      )
  );
  self.clients.claim();
});

self.addEventListener("fetch", (event) => {
  const request = event.request;
  if (request.method !== "GET" || !request.url.includes("/app/static/")) {
    return;
  }

  event.respondWith(
    caches.match(request).then((cached) => {
      if (cached) {
        return cached;
      }
      return fetch(request).then((response) => {
        const copy = response.clone();
        caches.open(CACHE_NAME).then((cache) => cache.put(request, copy));
        return response;
      });
    })
  );
});