|
@@ -0,0 +1,135 @@
|
|
|
|
+// This optional code is used to register a service worker.
|
|
|
|
+// register() is not called by default.
|
|
|
|
+
|
|
|
|
+// This lets the app load faster on subsequent visits in production, and gives
|
|
|
|
+// it offline capabilities. However, it also means that developers (and users)
|
|
|
|
+// will only see deployed updates on subsequent visits to a page, after all the
|
|
|
|
+// existing tabs open on the page have been closed, since previously cached
|
|
|
|
+// resources are updated in the background.
|
|
|
|
+
|
|
|
|
+// To learn more about the benefits of this model and instructions on how to
|
|
|
|
+// opt-in, read http://bit.ly/CRA-PWA
|
|
|
|
+
|
|
|
|
+const isLocalhost = Boolean(
|
|
|
|
+ window.location.hostname === 'localhost' ||
|
|
|
|
+ // [::1] is the IPv6 localhost address.
|
|
|
|
+ window.location.hostname === '[::1]' ||
|
|
|
|
+ // 127.0.0.1/8 is considered localhost for IPv4.
|
|
|
|
+ window.location.hostname.match(
|
|
|
|
+ /^127(?:\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)){3}$/
|
|
|
|
+ )
|
|
|
|
+);
|
|
|
|
+
|
|
|
|
+export function register(config) {
|
|
|
|
+ if (process.env.NODE_ENV === 'production' && 'serviceWorker' in navigator) {
|
|
|
|
+ // The URL constructor is available in all browsers that support SW.
|
|
|
|
+ const publicUrl = new URL(process.env.PUBLIC_URL, window.location.href);
|
|
|
|
+ if (publicUrl.origin !== window.location.origin) {
|
|
|
|
+ // Our service worker won't work if PUBLIC_URL is on a different origin
|
|
|
|
+ // from what our page is served on. This might happen if a CDN is used to
|
|
|
|
+ // serve assets; see https://github.com/facebook/create-react-app/issues/2374
|
|
|
|
+ return;
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ window.addEventListener('load', () => {
|
|
|
|
+ const swUrl = `${process.env.PUBLIC_URL}/service-worker.js`;
|
|
|
|
+
|
|
|
|
+ if (isLocalhost) {
|
|
|
|
+ // This is running on localhost. Let's check if a service worker still exists or not.
|
|
|
|
+ checkValidServiceWorker(swUrl, config);
|
|
|
|
+
|
|
|
|
+ // Add some additional logging to localhost, pointing developers to the
|
|
|
|
+ // service worker/PWA documentation.
|
|
|
|
+ navigator.serviceWorker.ready.then(() => {
|
|
|
|
+ console.log(
|
|
|
|
+ 'This web app is being served cache-first by a service ' +
|
|
|
|
+ 'worker. To learn more, visit http://bit.ly/CRA-PWA'
|
|
|
|
+ );
|
|
|
|
+ });
|
|
|
|
+ } else {
|
|
|
|
+ // Is not localhost. Just register service worker
|
|
|
|
+ registerValidSW(swUrl, config);
|
|
|
|
+ }
|
|
|
|
+ });
|
|
|
|
+ }
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+function registerValidSW(swUrl, config) {
|
|
|
|
+ navigator.serviceWorker
|
|
|
|
+ .register(swUrl)
|
|
|
|
+ .then(registration => {
|
|
|
|
+ registration.onupdatefound = () => {
|
|
|
|
+ const installingWorker = registration.installing;
|
|
|
|
+ if (installingWorker == null) {
|
|
|
|
+ return;
|
|
|
|
+ }
|
|
|
|
+ installingWorker.onstatechange = () => {
|
|
|
|
+ if (installingWorker.state === 'installed') {
|
|
|
|
+ if (navigator.serviceWorker.controller) {
|
|
|
|
+ // At this point, the updated precached content has been fetched,
|
|
|
|
+ // but the previous service worker will still serve the older
|
|
|
|
+ // content until all client tabs are closed.
|
|
|
|
+ console.log(
|
|
|
|
+ 'New content is available and will be used when all ' +
|
|
|
|
+ 'tabs for this page are closed. See http://bit.ly/CRA-PWA.'
|
|
|
|
+ );
|
|
|
|
+
|
|
|
|
+ // Execute callback
|
|
|
|
+ if (config && config.onUpdate) {
|
|
|
|
+ config.onUpdate(registration);
|
|
|
|
+ }
|
|
|
|
+ } else {
|
|
|
|
+ // At this point, everything has been precached.
|
|
|
|
+ // It's the perfect time to display a
|
|
|
|
+ // "Content is cached for offline use." message.
|
|
|
|
+ console.log('Content is cached for offline use.');
|
|
|
|
+
|
|
|
|
+ // Execute callback
|
|
|
|
+ if (config && config.onSuccess) {
|
|
|
|
+ config.onSuccess(registration);
|
|
|
|
+ }
|
|
|
|
+ }
|
|
|
|
+ }
|
|
|
|
+ };
|
|
|
|
+ };
|
|
|
|
+ })
|
|
|
|
+ .catch(error => {
|
|
|
|
+ console.error('Error during service worker registration:', error);
|
|
|
|
+ });
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+function checkValidServiceWorker(swUrl, config) {
|
|
|
|
+ // Check if the service worker can be found. If it can't reload the page.
|
|
|
|
+ fetch(swUrl)
|
|
|
|
+ .then(response => {
|
|
|
|
+ // Ensure service worker exists, and that we really are getting a JS file.
|
|
|
|
+ const contentType = response.headers.get('content-type');
|
|
|
|
+ if (
|
|
|
|
+ response.status === 404 ||
|
|
|
|
+ (contentType != null && contentType.indexOf('javascript') === -1)
|
|
|
|
+ ) {
|
|
|
|
+ // No service worker found. Probably a different app. Reload the page.
|
|
|
|
+ navigator.serviceWorker.ready.then(registration => {
|
|
|
|
+ registration.unregister().then(() => {
|
|
|
|
+ window.location.reload();
|
|
|
|
+ });
|
|
|
|
+ });
|
|
|
|
+ } else {
|
|
|
|
+ // Service worker found. Proceed as normal.
|
|
|
|
+ registerValidSW(swUrl, config);
|
|
|
|
+ }
|
|
|
|
+ })
|
|
|
|
+ .catch(() => {
|
|
|
|
+ console.log(
|
|
|
|
+ 'No internet connection found. App is running in offline mode.'
|
|
|
|
+ );
|
|
|
|
+ });
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+export function unregister() {
|
|
|
|
+ if ('serviceWorker' in navigator) {
|
|
|
|
+ navigator.serviceWorker.ready.then(registration => {
|
|
|
|
+ registration.unregister();
|
|
|
|
+ });
|
|
|
|
+ }
|
|
|
|
+}
|