CT/dist/sw.js

const CACHE_VERSION = "v2";

self.addEventListener("fetch", (event) => {
  event.respondWith(handleRequest(event));
});

async function handleRequest(event) {
  const response = await getFromCache(event);
  if (response) {
    fetchAndCache(event); // Call this but don't await, allowing the cache to update in the background
    return response;
  }
  return fetchAndCache(event);
}

async function getFromCache(event) {
  const request = event.request;
  const cache = await caches.open(CACHE_VERSION);
  const response = await cache.match(request);
  return response;
}

async function fetchAndCache(event) {
  const request = event.request;
  const response = await fetch(request);
  if (response.status === 200) { // Only cache successful responses
    const cache = await caches.open(CACHE_VERSION);
    cache.put(request, response.clone());
  }
  return response;
}