testing

service-worker.js

@@ -0,0 +1,13 @@
+self.addEventListener('fetch', function(event) {
+    event.respondWith(async function() {
+       try{
+         var res = await fetch(event.request);
+         var cache = await caches.open('cache');
+         cache.put(event.request.url, res.clone());
+         return res;
+       }
+       catch(error){
+         return caches.match(event.request);
+        }
+      }());
+  });