Move serviceworker to workbox and fix SSE interference

package.json

@@ -48,6 +48,8 @@
     "webpack": "4.43.0",
     "webpack-cli": "3.3.11",
     "webpack-fix-style-only-entries": "0.4.0",
+    "workbox-routing": "5.1.3",
+    "workbox-strategies": "5.1.3",
     "worker-loader": "2.0.0"
   },
   "devDependencies": {

routers/routes/routes.go

@@ -1048,10 +1048,6 @@ func RegisterRoutes(m *macaron.Macaron) {
 		ctx.HTML(200, "pwa/manifest_json")
 	})
 
-	m.Get("/serviceworker.js", templates.JSRenderer(), func(ctx *context.Context) {
-		ctx.HTML(200, "pwa/serviceworker_js")
-	})
-
 	// prometheus metrics endpoint
 	if setting.Metrics.Enabled {
 		c := metrics.NewCollector()

templates/base/head.tmpl

@@ -6,30 +6,6 @@
 	<meta http-equiv="x-ua-compatible" content="ie=edge">
 	<title>{{if .Title}}{{.Title | RenderEmojiPlain}} - {{end}} {{if .Repository.Name}}{{.Repository.Name}} - {{end}}{{AppName}} </title>
 	<link rel="manifest" href="{{AppSubUrl}}/manifest.json" crossorigin="use-credentials">
-	{{if UseServiceWorker}}
-	<script>
-		if ('serviceWorker' in navigator) {
-			navigator.serviceWorker.register('{{AppSubUrl}}/serviceworker.js').then(function(registration) {
-				// Registration was successful
-				console.info('ServiceWorker registration successful with scope: ', registration.scope);
-			}, function(err) {
-				// registration failed :(
-				console.info('ServiceWorker registration failed: ', err);
-			});
-		}
-	</script>
-	{{else}}
-	<script>
-		if ('serviceWorker' in navigator) {
-			navigator.serviceWorker.getRegistrations().then(function(registrations) {
-				registrations.forEach(function(registration) {
-					registration.unregister();
-					console.info('ServiceWorker unregistered');
-				});
-			});
-		}
-	</script>
-	{{end}}
 	<meta name="theme-color" content="{{ThemeColorMetaTag}}">
 	<meta name="author" content="{{if .Repository}}{{.Owner.Name}}{{else}}{{MetaAuthor}}{{end}}" />
 	<meta name="description" content="{{if .Repository}}{{.Repository.Name}}{{if .Repository.Description}} - {{.Repository.Description}}{{end}}{{else}}{{MetaDescription}}{{end}}" />
@@ -86,6 +62,7 @@
 		window.config = {
 			AppSubUrl: '{{AppSubUrl}}',
 			StaticUrlPrefix: '{{StaticUrlPrefix}}',
+			UseServiceWorker: {{UseServiceWorker}},
 			csrf: '{{.CsrfToken}}',
 			HighlightJS: {{if .RequireHighlightJS}}true{{else}}false{{end}},
 			Minicolors: {{if .RequireMinicolors}}true{{else}}false{{end}},

web_src/js/features/serviceworker.js

@@ -0,0 +1,24 @@
+const {UseServiceWorker, AppSubUrl} = window.config;
+
+async function unregister() {
+  for (const registration of await navigator.serviceWorker.getRegistrations()) {
+    const serviceWorker = registration.active;
+    if (!serviceWorker) continue;
+    registration.unregister();
+  }
+}
+
+export default async function initServiceWorker() {
+  if (!('serviceWorker' in navigator)) return;
+
+  if (UseServiceWorker) {
+    try {
+      await navigator.serviceWorker.register(`${AppSubUrl}/serviceworker.js`);
+    } catch (err) {
+      await unregister();
+      throw err;
+    }
+  } else {
+    await unregister();
+  }
+}

web_src/js/index.js

@@ -14,6 +14,7 @@ import initGitGraph from './features/gitgraph.js';
 import initClipboard from './features/clipboard.js';
 import initUserHeatmap from './features/userheatmap.js';
 import initDateTimePicker from './features/datetimepicker.js';
+import initServiceWorker from './features/serviceworker.js';
 import attachTribute from './features/tribute.js';
 import createDropzone from './features/dropzone.js';
 import highlight from './features/highlight.js';
@@ -2475,6 +2476,7 @@ $(document).ready(async () => {
     initGitGraph(),
     initClipboard(),
     initUserHeatmap(),
+    initServiceWorker(),
   ]);
 });
 

web_src/js/serviceworker.js

@@ -0,0 +1,14 @@
+import {registerRoute} from 'workbox-routing';
+import {StaleWhileRevalidate} from 'workbox-strategies';
+
+const cachedDestinations = new Set([
+  'manifest',
+  'script',
+  'style',
+  'worker',
+]);
+
+registerRoute(
+  ({request}) => cachedDestinations.has(request.destination),
+  new StaleWhileRevalidate({cacheName: 'static-cache-v2'}),
+);

webpack.config.js

@@ -35,13 +35,20 @@ module.exports = {
     jquery: [
       resolve(__dirname, 'web_src/js/jquery.js'),
     ],
+    serviceworker: [
+      resolve(__dirname, 'web_src/js/serviceworker.js'),
+    ],
     icons: glob('node_modules/@primer/octicons/build/svg/**/*.svg'),
     ...themes,
   },
   devtool: false,
   output: {
     path: resolve(__dirname, 'public'),
-    filename: 'js/[name].js',
+    filename: ({chunk}) => {
+      // serviceworker can only manage assets below it's script path so we
+      // have to put it in / instead of /js/
+      return chunk.id === 'serviceworker' ? '[name].js' : 'js/[name].js';
+    },
     chunkFilename: 'js/[name].js',
   },
   optimization: {