Remove the service worker and ui.USE_SERVICE_WORKER option

We don't really gain anything from it except the client-side caching
which is a problem better solved on HTTP level. Gitea is not a PWA and
will not do anything useful in a offline scenario without having access
to the server.

This should also resolve issues seen with the serviceworker interfering
on SSE requests.

The only API we can not use without a service worker is push
notifications while the "app" is closed but the more established
HTML Notification API will be a alternative.

Fixes: go-gitea#11092
Fixes: go-gitea#8056
Fixes: go-gitea#7372

.eslintrc

@@ -48,6 +48,7 @@ rules:
   no-cond-assign: [2, except-parens]
   no-console: [1, {allow: [info, warn, error]}]
   no-continue: [0]
+  no-empty: [2, {allowEmptyCatch: true}]
   no-eq-null: [2]
   no-mixed-operators: [0]
   no-multi-assign: [0]

docs/content/doc/advanced/config-cheat-sheet.en-us.md

@@ -133,7 +133,6 @@ Values containing `#` or `;` must be quoted using `` ` `` or `"""`.
     For custom reactions, add a tightly cropped square image to public/emoji/img/reaction_name.png
 - `DEFAULT_SHOW_FULL_NAME`: **false**: Whether the full name of the users should be shown where possible. If the full name isn't set, the username will be used.
 - `SEARCH_REPO_DESCRIPTION`: **true**: Whether to search within description at repository search on explore page.
-- `USE_SERVICE_WORKER`: **true**: Whether to enable a Service Worker to cache frontend assets.
 
 ### UI - Admin (`ui.admin`)
 

docs/content/doc/advanced/hacking-on-gitea.en-us.md

@@ -149,8 +149,6 @@ Before committing, make sure the linters pass:
 make lint-frontend
 ```
 
-Note: When working on frontend code, set `USE_SERVICE_WORKER` to `false` in `app.ini` to prevent undesirable caching of frontend assets.
-
 ### Building Images
 
 To build the images, ImageMagick, `inkscape` and `zopflipng` binaries must be available in

modules/setting/setting.go

@@ -179,7 +179,6 @@ var (
 		Reactions             []string
 		ReactionsMap          map[string]bool
 		SearchRepoDescription bool
-		UseServiceWorker      bool
 
 		Notification struct {
 			MinTimeout            time.Duration
@@ -1018,7 +1017,6 @@ func NewContext() {
 	UI.ShowUserEmail = Cfg.Section("ui").Key("SHOW_USER_EMAIL").MustBool(true)
 	UI.DefaultShowFullName = Cfg.Section("ui").Key("DEFAULT_SHOW_FULL_NAME").MustBool(false)
 	UI.SearchRepoDescription = Cfg.Section("ui").Key("SEARCH_REPO_DESCRIPTION").MustBool(true)
-	UI.UseServiceWorker = Cfg.Section("ui").Key("USE_SERVICE_WORKER").MustBool(true)
 
 	HasRobotsTxt = com.IsFile(path.Join(CustomPath, "robots.txt"))
 

modules/templates/helper.go

@@ -157,9 +157,6 @@ func NewFuncMap() []template.FuncMap {
 		"MetaKeywords": func() string {
 			return setting.UI.Meta.Keywords
 		},
-		"UseServiceWorker": func() bool {
-			return setting.UI.UseServiceWorker
-		},
 		"FilenameIsImage": func(filename string) bool {
 			mimeType := mime.TypeByExtension(filepath.Ext(filename))
 			return strings.HasPrefix(mimeType, "image/")

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}}" />

web_src/js/index.js

@@ -3594,3 +3594,14 @@ $.get(`${window.config.StaticUrlPrefix}/img/svg/icons.svg`, (data) => {
   div.innerHTML = new XMLSerializer().serializeToString(data.documentElement);
   document.body.insertBefore(div, document.body.childNodes[0]);
 });
+
+// remove any previously installed serviceworkers
+if ('serviceWorker' in navigator) {
+  try {
+    navigator.serviceWorker.getRegistrations().then((registrations) => {
+      for (const registration of registrations) {
+        registration.unregister();
+      }
+    });
+  } catch (_err) {}
+}