1 files changed, 43 insertions, 0 deletions
diff --git a/demo/sw.ts b/demo/sw.ts
new file mode 100644
index 0000000..0cdbcde
--- /dev/null
+++ b/demo/sw.ts
@@ -0,0 +1,43 @@
+/// <reference lib="webworker" />
+
+const sw = self as unknown as ServiceWorkerGlobalScope & {
+  __precacheManifest: ({ url: string, revision: string })[];
+};
+
+const precacheVersion = sw.__precacheManifest
+  .map(p => p.revision)
+  .join('');
+const precacheFiles = sw.__precacheManifest.map(p => p.url).filter(
+  u => /\.(ico)$/.test(u)
+);
+
+const ch = () => caches.open(precacheVersion);
+ 
+sw.addEventListener('install', ev => {
+  // Do not finish installing until every file in the app has been cached
+  ev.waitUntil(
+    ch().then(
+      cache => cache.addAll(precacheFiles)
+    )
+  );
+});
+ 
+sw.addEventListener('activate', ev => {
+  ev.waitUntil(
+    caches.keys().then(keys => Promise.all(
+      keys.filter(k => k !== precacheVersion).map(
+        k => caches.delete(k)
+      )
+    )).then(() => sw.clients.claim())
+  );
+});
+
+sw.addEventListener('fetch', ev => {
+  ev.respondWith(
+    caches.match(ev.request).then(resp => resp || ch().then(c =>
+      fetch(ev.request).then(res => c.put(ev.request, res.clone()).then(
+        () => res
+      ))
+    ))
+  )
+});
+\ No newline at end of file