2015-01-29 10:58:43 -05:00

74 lines
3.0 KiB
JavaScript

/*!
*
* Web Starter Kit
* Copyright 2014 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
*
* https://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
*
*/
(function() {
'use strict';
// Check to make sure service workers are supported in the current browser,
// and that the current page is accessed from a secure origin. Using a
// service worker from an insecure origin will trigger JS console errors. See
// http://www.chromium.org/Home/chromium-security/prefer-secure-origins-for-powerful-new-features
if ('serviceWorker' in navigator &&
(window.location.protocol === 'https:' ||
window.location.hostname === 'localhost' ||
window.location.hostname.indexOf('127.') === 0)) {
navigator.serviceWorker.register('/service-worker.js', {
scope: './'
}).then(function(registration) {
// Check to see if there's an updated version of service-worker.js with
// new files to cache:
// https://slightlyoff.github.io/ServiceWorker/spec/service_worker/index.html#service-worker-registration-update-method
if (typeof registration.update === 'function') {
registration.update();
}
// updatefound is fired if service-worker.js changes.
registration.onupdatefound = function() {
// updatefound is also fired the very first time the SW is installed,
// and there's no need to prompt for a reload at that point.
// So check here to see if the page is already controlled,
// i.e. whether there's an existing service worker.
if (navigator.serviceWorker.controller) {
// The updatefound event implies that registration.installing is set:
// https://slightlyoff.github.io/ServiceWorker/spec/service_worker/index.html#service-worker-container-updatefound-event
var installingWorker = registration.installing;
installingWorker.onstatechange = function() {
switch (installingWorker.state) {
case 'installed':
// At this point, the old content will have been purged and the
// fresh content will have been added to the cache.
// It's the perfect time to display a "New content is
// available; please refresh." message in the page's interface.
break;
case 'redundant':
throw 'The installing service worker became redundant.';
}
};
}
};
}).catch(function(e) {
console.error('Error during service worker registration:', e);
});
}
// Your custom JavaScript goes here
})();