From 655def514116f67a11986a3dd6edd768e9ac9447 Mon Sep 17 00:00:00 2001
From: silverwind <me@silverwind.io>
Date: Fri, 22 May 2020 17:46:39 +0200
Subject: [PATCH] Move serviceworker to workbox and fix SSE interference
 (#11538) (#11547)

* Move serviceworker to workbox and fix SSE interference

Instead of statically hardcoding every frontend asset, this uses a
type-based approach to cache all js,css and manifest.json requests.

This also fixes the issue that the service worker was interfering with
EventSource because it was unconditionally handling all requests which
this new implementation doesn't.

Fixes: https://github.com/go-gitea/gitea/issues/11092
Fixes: https://github.com/go-gitea/gitea/issues/7372

* rethrow error instead of logging

* await .register

* Revert "rethrow error instead of logging"

This reverts commit 043162ba1f18b98a4bf9635959fd28d16e839fc5.

* improve comment

* remove JSRenderer

* add version-based cache invalidation

* refactor

* more refactor

* remove comment

* rename item to fit cache name

Co-authored-by: guillep2k <18600385+guillep2k@users.noreply.github.com>
---
 .eslintrc                            |  1 +
 modules/templates/dynamic.go         | 12 ----
 modules/templates/static.go          |  9 ---
 package-lock.json                    | 22 ++++++++
 package.json                         |  2 +
 routers/routes/routes.go             |  4 --
 templates/base/head.tmpl             | 26 +--------
 templates/pwa/serviceworker_js.tmpl  | 83 ----------------------------
 web_src/js/features/serviceworker.js | 43 ++++++++++++++
 web_src/js/index.js                  |  2 +
 web_src/js/serviceworker.js          | 16 ++++++
 webpack.config.js                    |  9 ++-
 12 files changed, 96 insertions(+), 133 deletions(-)
 delete mode 100644 templates/pwa/serviceworker_js.tmpl
 create mode 100644 web_src/js/features/serviceworker.js
 create mode 100644 web_src/js/serviceworker.js

diff --git a/.eslintrc b/.eslintrc
index 8f337baec..3a731cbf6 100644
--- a/.eslintrc
+++ b/.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]
diff --git a/modules/templates/dynamic.go b/modules/templates/dynamic.go
index 6153e8d02..bd1c4d06c 100644
--- a/modules/templates/dynamic.go
+++ b/modules/templates/dynamic.go
@@ -48,18 +48,6 @@ func JSONRenderer() macaron.Handler {
 	})
 }
 
-// JSRenderer implements the macaron handler for serving JS templates.
-func JSRenderer() macaron.Handler {
-	return macaron.Renderer(macaron.RenderOptions{
-		Funcs:     NewFuncMap(),
-		Directory: path.Join(setting.StaticRootPath, "templates"),
-		AppendDirectories: []string{
-			path.Join(setting.CustomPath, "templates"),
-		},
-		HTMLContentType: "application/javascript",
-	})
-}
-
 // Mailer provides the templates required for sending notification mails.
 func Mailer() (*texttmpl.Template, *template.Template) {
 	for _, funcs := range NewTextFuncMap() {
diff --git a/modules/templates/static.go b/modules/templates/static.go
index 5bc4e33e1..a3aff5e56 100644
--- a/modules/templates/static.go
+++ b/modules/templates/static.go
@@ -132,15 +132,6 @@ func JSONRenderer() macaron.Handler {
 	})
 }
 
-// JSRenderer implements the macaron handler for serving JS templates.
-func JSRenderer() macaron.Handler {
-	return macaron.Renderer(macaron.RenderOptions{
-		Funcs:              NewFuncMap(),
-		TemplateFileSystem: NewTemplateFileSystem(),
-		HTMLContentType:    "application/javascript",
-	})
-}
-
 // Mailer provides the templates required for sending notification mails.
 func Mailer() (*texttmpl.Template, *template.Template) {
 	for _, funcs := range NewTextFuncMap() {
diff --git a/package-lock.json b/package-lock.json
index 71183fed4..2f1c58073 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -14852,6 +14852,28 @@
       "resolved": "https://registry.npmjs.org/wordwrap/-/wordwrap-0.0.2.tgz",
       "integrity": "sha1-t5Zpu0LstAn4PVg8rVLKF+qhZD8="
     },
+    "workbox-core": {
+      "version": "5.1.3",
+      "resolved": "https://registry.npmjs.org/workbox-core/-/workbox-core-5.1.3.tgz",
+      "integrity": "sha512-TFSIPxxciX9sFaj0FDiohBeIKpwMcCyNduydi9i3LChItcndDS6TJpErxybv8aBWeCMraXt33TWtF6kKuIObNw=="
+    },
+    "workbox-routing": {
+      "version": "5.1.3",
+      "resolved": "https://registry.npmjs.org/workbox-routing/-/workbox-routing-5.1.3.tgz",
+      "integrity": "sha512-F+sAp9Iy3lVl3BEG+pzXWVq4AftzjiFpHDaZ4Kf4vLoBoKQE0hIHet4zE5DpHqYdyw+Udhp4wrfHamX6PN6z1Q==",
+      "requires": {
+        "workbox-core": "^5.1.3"
+      }
+    },
+    "workbox-strategies": {
+      "version": "5.1.3",
+      "resolved": "https://registry.npmjs.org/workbox-strategies/-/workbox-strategies-5.1.3.tgz",
+      "integrity": "sha512-wiXHfmOKnWABeIVW+/ye0e00+2CcS5y7SIj2f9zcdy2ZLEbcOf7B+yOl5OrWpBGlTUwRjIYhV++ZqiKm3Dc+8w==",
+      "requires": {
+        "workbox-core": "^5.1.3",
+        "workbox-routing": "^5.1.3"
+      }
+    },
     "worker-farm": {
       "version": "1.7.0",
       "resolved": "https://registry.npmjs.org/worker-farm/-/worker-farm-1.7.0.tgz",
diff --git a/package.json b/package.json
index 7fb8246af..ce14631d7 100644
--- a/package.json
+++ b/package.json
@@ -47,6 +47,8 @@
     "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": {
diff --git a/routers/routes/routes.go b/routers/routes/routes.go
index 7f409eb57..d739f0b6c 100644
--- a/routers/routes/routes.go
+++ b/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()
diff --git a/templates/base/head.tmpl b/templates/base/head.tmpl
index eae238923..0234d2e29 100644
--- a/templates/base/head.tmpl
+++ b/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}}" />
@@ -84,8 +60,10 @@
 	</script>
 	<script>
 		window.config = {
+			AppVer: '{{AppVer}}',
 			AppSubUrl: '{{AppSubUrl}}',
 			StaticUrlPrefix: '{{StaticUrlPrefix}}',
+			UseServiceWorker: {{UseServiceWorker}},
 			csrf: '{{.CsrfToken}}',
 			HighlightJS: {{if .RequireHighlightJS}}true{{else}}false{{end}},
 			Minicolors: {{if .RequireMinicolors}}true{{else}}false{{end}},
diff --git a/templates/pwa/serviceworker_js.tmpl b/templates/pwa/serviceworker_js.tmpl
deleted file mode 100644
index 32975e0fd..000000000
--- a/templates/pwa/serviceworker_js.tmpl
+++ /dev/null
@@ -1,83 +0,0 @@
-var STATIC_CACHE = 'static-cache-v1';
-var urlsToCache = [
-  // js
-  '{{StaticUrlPrefix}}/fomantic/semantic.min.js?v={{MD5 AppVer}}',
-  '{{StaticUrlPrefix}}/js/clipboard.js',
-  '{{StaticUrlPrefix}}/js/gitgraph.js',
-  '{{StaticUrlPrefix}}/js/highlight.js',
-  '{{StaticUrlPrefix}}/js/index.js?v={{MD5 AppVer}}',
-  '{{StaticUrlPrefix}}/js/jquery.js?v={{MD5 AppVer}}',
-  '{{StaticUrlPrefix}}/js/swagger.js?v={{MD5 AppVer}}',
-  '{{StaticUrlPrefix}}/js/dropzone.js',
-  '{{StaticUrlPrefix}}/js/datetimepicker.js',
-  '{{StaticUrlPrefix}}/vendor/plugins/codemirror/addon/mode/loadmode.js',
-  '{{StaticUrlPrefix}}/vendor/plugins/codemirror/mode/meta.js',
-  '{{StaticUrlPrefix}}/vendor/plugins/jquery.minicolors/jquery.minicolors.min.js',
-  '{{StaticUrlPrefix}}/vendor/plugins/simplemde/simplemde.min.js',
-
-  // css
-  '{{StaticUrlPrefix}}/css/index.css?v={{MD5 AppVer}}',
-  '{{StaticUrlPrefix}}/css/swagger.css?v={{MD5 AppVer}}',
-  '{{StaticUrlPrefix}}/css/dropzone.css',
-  '{{StaticUrlPrefix}}/css/datetimepicker.css',
-  '{{StaticUrlPrefix}}/fomantic/semantic.min.css?v={{MD5 AppVer}}',
-  '{{StaticUrlPrefix}}/vendor/assets/font-awesome/css/font-awesome.min.css',
-  '{{StaticUrlPrefix}}/vendor/plugins/jquery.minicolors/jquery.minicolors.css',
-  '{{StaticUrlPrefix}}/vendor/plugins/simplemde/simplemde.min.css',
-  '{{StaticUrlPrefix}}/vendor/plugins/tribute/tribute.css',
-{{if .IsSigned }}
-	{{ if ne .SignedUser.Theme "gitea" }}
-		'{{StaticUrlPrefix}}/css/theme-{{.SignedUser.Theme}}.css?v={{MD5 AppVer}}',
-	{{end}}
-{{else if ne DefaultTheme "gitea"}}
-	'{{StaticUrlPrefix}}/css/theme-{{DefaultTheme}}.css?v={{MD5 AppVer}}',
-{{end}}
-
-  // img
-  '{{StaticUrlPrefix}}/img/gitea-sm.png',
-  '{{StaticUrlPrefix}}/img/gitea-lg.png',
-
-  // svg
-  '{{StaticUrlPrefix}}/img/svg/icons.svg',
-
-  // fonts
-  '{{StaticUrlPrefix}}/fomantic/themes/default/assets/fonts/icons.woff2',
-  '{{StaticUrlPrefix}}/vendor/assets/roboto-fonts/roboto-v20-latin-ext_cyrillic-ext_latin_greek_vietnamese_cyrillic_greek-ext-regular.woff2',
-  '{{StaticUrlPrefix}}/vendor/assets/roboto-fonts/roboto-v20-latin-ext_cyrillic-ext_latin_greek_vietnamese_cyrillic_greek-ext-italic.woff2',
-  '{{StaticUrlPrefix}}/vendor/assets/roboto-fonts/roboto-v20-latin-ext_cyrillic-ext_latin_greek_vietnamese_cyrillic_greek-ext-700.woff2',
-  '{{StaticUrlPrefix}}/vendor/assets/roboto-fonts/roboto-v20-latin-ext_cyrillic-ext_latin_greek_vietnamese_cyrillic_greek-ext-700italic.woff2',
-
-  // monaco
-  '{{StaticUrlPrefix}}/css/monaco.css',
-  '{{StaticUrlPrefix}}/fonts/codicon.ttf',
-  '{{StaticUrlPrefix}}/js/monaco-css.worker.js',
-  '{{StaticUrlPrefix}}/js/monaco-editor.worker.js',
-  '{{StaticUrlPrefix}}/js/monaco-html.worker.js',
-  '{{StaticUrlPrefix}}/js/monaco-json.worker.js',
-  '{{StaticUrlPrefix}}/js/monaco.js',
-  '{{StaticUrlPrefix}}/js/monaco-ts.worker.js'
-];
-
-self.addEventListener('install', function (event) {
-  // Perform install steps
-  event.waitUntil(
-    caches.open(STATIC_CACHE)
-      .then(function (cache) {
-        return cache.addAll(urlsToCache);
-      })
-  );
-});
-
-self.addEventListener('fetch', function (event) {
-  event.respondWith(
-    caches.match(event.request)
-      .then(function (response) {
-        // Cache hit - return response
-        if (response) {
-          return response;
-        }
-        return fetch(event.request);
-      }
-      )
-  );
-});
diff --git a/web_src/js/features/serviceworker.js b/web_src/js/features/serviceworker.js
new file mode 100644
index 000000000..a8fd2d41d
--- /dev/null
+++ b/web_src/js/features/serviceworker.js
@@ -0,0 +1,43 @@
+const {UseServiceWorker, AppSubUrl, AppVer} = window.config;
+const cacheName = 'static-cache-v2';
+
+async function unregister() {
+  for (const registration of await navigator.serviceWorker.getRegistrations()) {
+    const serviceWorker = registration.active;
+    if (!serviceWorker) continue;
+    registration.unregister();
+  }
+}
+
+async function invalidateCache() {
+  await caches.delete(cacheName);
+}
+
+async function checkCacheValidity() {
+  const cacheKey = AppVer;
+  const storedCacheKey = localStorage.getItem('staticCacheKey');
+
+  // invalidate cache if it belongs to a different gitea version
+  if (cacheKey && storedCacheKey !== cacheKey) {
+    invalidateCache();
+    localStorage.setItem('staticCacheKey', cacheKey);
+  }
+}
+
+export default async function initServiceWorker() {
+  if (!('serviceWorker' in navigator)) return;
+
+  if (UseServiceWorker) {
+    await checkCacheValidity();
+    try {
+      await navigator.serviceWorker.register(`${AppSubUrl}/serviceworker.js`);
+    } catch (err) {
+      console.error(err);
+      await invalidateCache();
+      await unregister();
+    }
+  } else {
+    await invalidateCache();
+    await unregister();
+  }
+}
diff --git a/web_src/js/index.js b/web_src/js/index.js
index f73aac2bd..96b5f4673 100644
--- a/web_src/js/index.js
+++ b/web_src/js/index.js
@@ -15,6 +15,7 @@ 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 {initTribute, issuesTribute, emojiTribute} from './features/tribute.js';
 import createDropzone from './features/dropzone.js';
 import highlight from './features/highlight.js';
@@ -2477,6 +2478,7 @@ $(document).ready(async () => {
     initGitGraph(),
     initClipboard(),
     initUserHeatmap(),
+    initServiceWorker(),
   ]);
 });
 
diff --git a/web_src/js/serviceworker.js b/web_src/js/serviceworker.js
new file mode 100644
index 000000000..e9dfde22f
--- /dev/null
+++ b/web_src/js/serviceworker.js
@@ -0,0 +1,16 @@
+import {registerRoute} from 'workbox-routing';
+import {StaleWhileRevalidate} from 'workbox-strategies';
+
+const cacheName = 'static-cache-v2';
+
+const cachedDestinations = new Set([
+  'manifest',
+  'script',
+  'style',
+  'worker',
+]);
+
+registerRoute(
+  ({request}) => cachedDestinations.has(request.destination),
+  new StaleWhileRevalidate({cacheName}),
+);
diff --git a/webpack.config.js b/webpack.config.js
index d6a632ad1..b1038c407 100644
--- a/webpack.config.js
+++ b/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's directory so
+      // we have to put it in / instead of /js/
+      return chunk.id === 'serviceworker' ? '[name].js' : 'js/[name].js';
+    },
     chunkFilename: 'js/[name].js',
   },
   optimization: {