Initial commitHEADmain

1 files changed, 29 insertions, 0 deletions

diff --git a/sw1.js b/sw1.js
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+++ b/sw1.js
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+// https://gist.github.com/adactio/3717b7da007a9363ddf21f584aae34af
+
+// HTML files: try the network first, then the cache.
+// Other files: try the cache first, then the network.
+// Both: cache a fresh version if possible.
+// (beware: the cache will grow and grow; there's no cleanup)
+
+const cacheName = "appname-files";
+
+addEventListener("fetch", fetchEvent => {
+  const request = fetchEvent.request;
+  if (request.method !== "GET") return;
+  fetchEvent.respondWith(async () => {
+    const fetchPromise = fetch(request);
+    fetchEvent.waitUntil(async () => {
+      const responseFromFetch = await fetchPromise;
+      const responseCopy = responseFromFetch.clone();
+      const myCache = await caches.open(cacheName);
+      return myCache.put(request, responseCopy);
+    }());
+    if (request.headers.get("Accept").includes("text/html")) {
+      try { return await fetchPromise; }
+      catch(error) { return caches.match(request); }
+    } else {
+      const responseFromCache = await caches.match(request);
+      return responseFromCache || fetchPromise;
+    }
+  }());
+});