add service worker script

Author: addyosmani

src/scripts/sw.js

@@ -0,0 +1,115 @@
+/**
+ * Copyright 2015 Google Inc. All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+importScripts('third_party/serviceworker-cache-polyfill.js');
+
+var CACHE_NAME = 'appshell';
+var CACHE_VERSION = '@VERSION@';
+
+self.oninstall = function(event) {
+
+  var urls = [
+
+    '/',
+    '/images/chrome-touch-icon-192x192.png',
+
+    '/images/[email protected]',
+
+    '/images/ic_menu_24px.svg',
+    '/images/ic_add_24px.svg',
+    '/images/ic_info_outline_24px.svg',
+
+    '/scripts/core.js',
+    '/scripts/list.js',
+
+    '/styles/core.css',
+    '/styles/list.css',
+
+    '/third_party/Roboto/Roboto-400.woff',
+    '/third_party/Roboto/Roboto-500.woff',
+
+    '/favicon.ico',
+    '/manifest.json'
+
+  ];
+
+  urls = urls.map(function(url) {
+    return new Request(url, {credentials: 'include'});
+  });
+
+  event.waitUntil(
+    caches
+      .open(CACHE_NAME + '-v' + CACHE_VERSION)
+      .then(function(cache) {
+        return cache.addAll(urls);
+      })
+  );
+
+};
+
+self.onactivate = function(event) {
+
+  var currentCacheName = CACHE_NAME + '-v' + CACHE_VERSION;
+  caches.keys().then(function(cacheNames) {
+
+    return Promise.all(
+      cacheNames.map(function(cacheName) {
+        if (cacheName.indexOf(CACHE_NAME) == -1) {
+          return;
+        }
+
+        if (cacheName != currentCacheName) {
+          return caches.delete(cacheName);
+        }
+      })
+    );
+  });
+
+};
+
+self.onfetch = function(event) {
+
+  var request = event.request;
+  var url = new URL(request.url);
+  var validSubsections = [
+    'create', 'details', 'edit', ''
+  ];
+
+  var subsection = /^\/([^\/]*)/.exec(url.pathname)[1];
+
+  event.respondWith(
+
+    // Check the cache for a hit.
+    caches.match(request).then(function(response) {
+
+      // If we have a response return it.
+      if (response)
+        return response;
+
+      // Otherwise return index.html file.
+      if (validSubsections.indexOf(subsection) >= 0)
+        return caches.match('/');
+
+      // We may get requests for analytics so
+      // do a very dumb check for that.
+      if (url.host.indexOf('voice') === -1)
+        return fetch(request);
+
+      // And worst case we fire out a not found.
+      return new Response('Sorry, not found');
+    })
+  );
+};