Fix the service worker generation problem

client/package.json

@@ -39,7 +39,8 @@
     "spin.js": "^4.1.0",
     "sweetalert2": "^9.8.2",
     "toastr": "^2.1.4",
-    "uuid": "^7.0.3"
+    "uuid": "^7.0.3",
+    "workbox-webpack-plugin": "^7.1.0"
   },
   "devDependencies": {
     "react-scripts": "^5.0.1"

client/src/index.js

@@ -6,7 +6,7 @@ import React from 'react';
 import ReactDOM from 'react-dom';
 import './index.css';
 import App from './App';
-import * as serviceWorker from './serviceWorker';
+import * as serviceWorkerRegistration from './serviceWorkerRegistration';
 import {Provider} from 'mobx-react';
 import {IntlProvider} from 'react-intl';
 import {messages} from './lang';
@@ -31,4 +31,4 @@ ReactDOM.render(<Root/>, document.getElementById('root'));
 // If you want your app to work offline and load faster, you can change
 // unregister() to register() below. Note this comes with some pitfalls.
 // Learn more about service workers: http://bit.ly/CRA-PWA
-serviceWorker.register({});
+serviceWorkerRegistration.unregister();

client/src/service-worker.js

@@ -0,0 +1,72 @@
+/* eslint-disable no-restricted-globals */
+
+// This service worker can be customized!
+// See https://developers.google.com/web/tools/workbox/modules
+// for the list of available Workbox modules, or add any other
+// code you'd like.
+// You can also remove this file if you'd prefer not to use a
+// service worker, and the Workbox build step will be skipped.
+
+import { clientsClaim } from 'workbox-core';
+import { ExpirationPlugin } from 'workbox-expiration';
+import { precacheAndRoute, createHandlerBoundToURL } from 'workbox-precaching';
+import { registerRoute } from 'workbox-routing';
+import { StaleWhileRevalidate } from 'workbox-strategies';
+
+clientsClaim();
+
+// Precache all of the assets generated by your build process.
+// Their URLs are injected into the manifest variable below.
+// This variable must be present somewhere in your service worker file,
+// even if you decide not to use precaching. See https://cra.link/PWA
+precacheAndRoute(self.__WB_MANIFEST);
+
+// Set up App Shell-style routing, so that all navigation requests
+// are fulfilled with your index.html shell. Learn more at
+// https://developers.google.com/web/fundamentals/architecture/app-shell
+const fileExtensionRegexp = new RegExp('/[^/?]+\\.[^/]+$');
+registerRoute(
+  // Return false to exempt requests from being fulfilled by index.html.
+  ({ request, url }) => {
+    // If this isn't a navigation, skip.
+    if (request.mode !== 'navigate') {
+      return false;
+    } // If this is a URL that starts with /_, skip.
+
+    if (url.pathname.startsWith('/_')) {
+      return false;
+    } // If this looks like a URL for a resource, because it contains // a file extension, skip.
+
+    if (url.pathname.match(fileExtensionRegexp)) {
+      return false;
+    } // Return true to signal that we want to use the handler.
+
+    return true;
+  },
+  createHandlerBoundToURL(process.env.PUBLIC_URL + '/index.html')
+);
+
+// An example runtime caching route for requests that aren't handled by the
+// precache, in this case same-origin .png requests like those from in public/
+registerRoute(
+  // Add in any other file extensions or routing criteria as needed.
+  ({ url }) => url.origin === self.location.origin && url.pathname.endsWith('.png'), // Customize this strategy as needed, e.g., by changing to CacheFirst.
+  new StaleWhileRevalidate({
+    cacheName: 'images',
+    plugins: [
+      // Ensure that once this runtime cache reaches a maximum size the
+      // least-recently used images are removed.
+      new ExpirationPlugin({ maxEntries: 50 }),
+    ],
+  })
+);
+
+// This allows the web app to trigger skipWaiting via
+// registration.waiting.postMessage({type: 'SKIP_WAITING'})
+self.addEventListener('message', (event) => {
+  if (event.data && event.data.type === 'SKIP_WAITING') {
+    self.skipWaiting();
+  }
+});
+
+// Any other custom service worker logic can go here.

client/src/serviceWorkerRegistration.js

@@ -1,27 +1,27 @@
-// In production, we register a service worker to serve assets from local cache.
+// 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 the "N+1" visit to a page, since previously
-// cached resources are updated in the background.
+// 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, read https://goo.gl/KwvDNy.
-// This link also includes instructions on opting out of this behavior.
+// To learn more about the benefits of this model and instructions on how to
+// opt-in, read https://cra.link/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}$/
-    )
+    // 127.0.0.0/8 are considered localhost for IPv4.
+    window.location.hostname.match(/^127(?:\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)){3}$/)
 );
 
 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);
+    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
@@ -41,11 +41,11 @@ export function register(config) {
         navigator.serviceWorker.ready.then(() => {
           console.log(
             'This web app is being served cache-first by a service ' +
-              'worker. To learn more, visit https://goo.gl/SC7cgQ'
+              'worker. To learn more, visit https://cra.link/PWA'
           );
         });
       } else {
-        // Is not local host. Just register service worker
+        // Is not localhost. Just register service worker
         registerValidSW(swUrl, config);
       }
     });
@@ -55,20 +55,25 @@ export function register(config) {
 function registerValidSW(swUrl, config) {
   navigator.serviceWorker
     .register(swUrl)
-    .then(registration => {
+    .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 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 your web app.
-              console.log('New content is available; please refresh.');
+              // 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 https://cra.link/PWA.'
+              );
 
               // Execute callback
-              if (config.onUpdate) {
+              if (config && config.onUpdate) {
                 config.onUpdate(registration);
               }
             } else {
@@ -78,7 +83,7 @@ function registerValidSW(swUrl, config) {
               console.log('Content is cached for offline use.');
 
               // Execute callback
-              if (config.onSuccess) {
+              if (config && config.onSuccess) {
                 config.onSuccess(registration);
               }
             }
@@ -86,22 +91,25 @@ function registerValidSW(swUrl, config) {
         };
       };
     })
-    .catch(error => {
+    .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 => {
+  fetch(swUrl, {
+    headers: { 'Service-Worker': 'script' },
+  })
+    .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 ||
-        response.headers.get('content-type').indexOf('javascript') === -1
+        (contentType != null && contentType.indexOf('javascript') === -1)
       ) {
         // No service worker found. Probably a different app. Reload the page.
-        navigator.serviceWorker.ready.then(registration => {
+        navigator.serviceWorker.ready.then((registration) => {
           registration.unregister().then(() => {
             window.location.reload();
           });
@@ -112,16 +120,18 @@ function checkValidServiceWorker(swUrl, config) {
       }
     })
     .catch(() => {
-      console.log(
-        'No internet connection found. App is running in offline mode.'
-      );
+      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();
-    });
+    navigator.serviceWorker.ready
+      .then((registration) => {
+        registration.unregister();
+      })
+      .catch((error) => {
+        console.error(error.message);
+      });
   }
 }