Improved CSS reloads in service worker

scripts/AnimeNotifier.ts

@@ -250,6 +250,10 @@ export class AnimeNotifier {
 				}
 				
 				break
+			
+			case "reload page":
+				location.reload(true)
+				break
 		}
 	}
 

sw/service-worker.ts

@@ -1,6 +1,5 @@
 // pack:ignore
 
-const CACHE = "v-3"
 const RELOADS = new Map<string, Promise<Response>>()
 const ETAGS = new Map<string, string>()
 const CACHEREFRESH = new Map<string, Promise<void>>()
@@ -18,24 +17,55 @@ const EXCLUDECACHE = new Set<string>([
 	"/from/",
 
 	// Chrome extension
-	"chrome-extension"
+	"chrome-extension",
+
+	// Authorization paths /auth/ and /logout are not listed here because they are handled in a special way.
 ])
 
-self.addEventListener("install", (evt: InstallEvent) => {
+class MyCache {
+	version: string
+
+	constructor(version: string) {
+		this.version = version
+	}
+
+	store(request: RequestInfo, response: Response) {
+		return caches.open(this.version).then(cache => {
+			return cache.put(request, response)
+		})
+	}
+}
+
+class MyServiceWorker {
+	cache: MyCache
+	currentCSP: string
+
+	constructor() {
+		this.cache = new MyCache("v-3")
+		this.currentCSP = ""
+		
+		self.addEventListener("install", (evt: InstallEvent) => evt.waitUntil(this.onInstall(evt)))
+		self.addEventListener("activate", (evt: any) => evt.waitUntil(this.onActivate(evt)))
+		self.addEventListener("fetch", (evt: FetchEvent) => evt.waitUntil(this.onRequest(evt)))
+		self.addEventListener("message", (evt: any) => evt.waitUntil(this.onMessage(evt)))
+		self.addEventListener("push", (evt: PushEvent) => evt.waitUntil(this.onPush(evt)))
+		self.addEventListener("pushsubscriptionchange", (evt: any) => evt.waitUntil(this.onPushSubscriptionChange(evt)))
+		self.addEventListener("notificationclick", (evt: NotificationEvent) => evt.waitUntil(this.onNotificationClick(evt)))
+	}
+
+	onInstall(evt: InstallEvent) {
 		console.log("service worker install")
 	
-	evt.waitUntil(
+		return (self as any).skipWaiting().then(() => {
-		(self as any).skipWaiting().then(() => {
+			return this.installCache()
-			return installCache()
 		})
-	)
+	}
-})
 
-self.addEventListener("activate", (evt: any) => {
+	onActivate(evt: any) {
 		console.log("service worker activate")
 	
-	// Delete old cache
+		// Only keep current version of the cache and delete old caches
-	let cacheWhitelist = [CACHE]
+		let cacheWhitelist = [this.cache.version]
 	
 		let deleteOldCache = caches.keys().then(keyList => {
 			return Promise.all(keyList.map(key => {
@@ -45,125 +75,49 @@ self.addEventListener("activate", (evt: any) => {
 			}))
 		})
 		
+		// Immediate claim helps us gain control over a new client immediately
 		let immediateClaim = (self as any).clients.claim()
 	
-	// Immediate claim
+		return Promise.all([
-	evt.waitUntil(
-		Promise.all([
 			deleteOldCache,
 			immediateClaim
 		])
-	)
-})
-
-// controlling service worker
-self.addEventListener("message", (evt: any) => {
-	let message = JSON.parse(evt.data)
-
-	let url = message.url
-	let refresh = RELOADS.get(url)
-	let servedETag = ETAGS.get(url)
-
-	// If the user requests a sub-page we should prefetch the full page, too.
-	if(url.includes("/_/")) {
-		let fullPage = new Request(url.replace("/_/", "/"))
-
-		fetch(fullPage, {
-			credentials: "same-origin"
-		})
-		.then(response => {
-			// Save the new version of the resource in the cache
-			let cacheRefresh = caches.open(CACHE).then(cache => {
-				return cache.put(fullPage, response)
-			})
-
-			CACHEREFRESH.set(fullPage.url, cacheRefresh)
-			return cacheRefresh
-		})
 	}
 
-	if(!refresh || !servedETag) {
+	onRequest(evt: FetchEvent) {
-		return
-	}
-	
-	evt.waitUntil(
-		refresh.then((response: Response) => {
-			// If the fresh copy was used to serve the request instead of the cache,
-			// we don"t need to tell the client to do a refresh.
-			if(response.bodyUsed) {
-				return
-			}
-
-			let eTag = response.headers.get("ETag")
-
-			if(eTag === servedETag) {
-				return
-			}
-
-			ETAGS.set(url, eTag)
-
-			let message = {
-				type: "new content",
-				url
-			}
-
-			let cacheRefresh = CACHEREFRESH.get(url)
-
-			if(!cacheRefresh) {
-				console.log("forcing reload, cache refresh null")
-				return evt.source.postMessage(JSON.stringify(message))
-			}
-
-			return cacheRefresh.then(() => {
-				console.log("forcing reload after cache refresh")
-				evt.source.postMessage(JSON.stringify(message))
-			})
-		})
-	)
-})
-
-self.addEventListener("fetch", async (evt: FetchEvent) => {
 		let request = evt.request as Request
-	let isAuth = request.url.includes("/auth/") || request.url.includes("/logout")
-	let ignoreCache = false
 
 		// console.log("fetch:", request.url)
 
+		// If it's not a GET request, fetch it normally
+		if(request.method !== "GET") {
+			return evt.respondWith(fetch(request))
+		}
+
+		// Clear cache on authentication and fetch it normally
+		if(request.url.includes("/auth/") || request.url.includes("/logout")) {
+			return caches.delete(this.cache.version).then(() => evt.respondWith(fetch(request)))
+		}
+
 		// Exclude certain URLs from being cached
 		for(let pattern of EXCLUDECACHE.keys()) {
 			if(request.url.includes(pattern)) {
-			ignoreCache = true
+				return evt.respondWith(fetch(request))
-			break
 			}
 		}
 	
-	// Delete existing cache on authentication
+		// If the request included the header "X-CacheOnly", return a cache-only response.
-	if(isAuth) {
+		// This is used in reloads to avoid generating a 2nd request after a cache refresh.
-		caches.delete(CACHE)
-	}
-
-	// Do not use cache in some cases
-	if(request.method !== "GET" || isAuth || ignoreCache) {
-		return evt.waitUntil(evt.respondWith(fetch(request)))
-	}
-
-	// Forced cache response?
 		if(request.headers.get("X-CacheOnly") === "true") {
-		// console.log("forced cache response")
+			return this.fromCache(request)
-		return evt.waitUntil(fromCache(request))
 		}
 		
-	let servedETag = undefined
-	
 		// Start fetching the request
 		let refresh = fetch(request).then(response => {
-		// console.log(response)
 			let clone = response.clone()
 	
 			// Save the new version of the resource in the cache
-		let cacheRefresh = caches.open(CACHE).then(cache => {
+			let cacheRefresh = this.cache.store(request, clone)
-			return cache.put(request, clone)
-		})
 	
 			CACHEREFRESH.set(request.url, cacheRefresh)
 	
@@ -174,44 +128,108 @@ self.addEventListener("fetch", async (evt: FetchEvent) => {
 		RELOADS.set(request.url, refresh)
 	
 		// Forced reload
-	if(request.headers.get("X-Reload") === "true") {
+		let servedETag = undefined
-		return evt.waitUntil(evt.respondWith(refresh.then(response => {
+
+		let onResponse = response => {
 			servedETag = response.headers.get("ETag")
 			ETAGS.set(request.url, servedETag)
 			return response
-		})))
+		}
+
+		if(request.headers.get("X-Reload") === "true") {
+			return evt.respondWith(refresh.then(onResponse))
 		}
 	
 		// Try to serve cache first and fall back to network response
-	let networkOrCache = fromCache(request).then(response => {
+		let networkOrCache = this.fromCache(request).then(onResponse).catch(error => {
-		// console.log("served from cache:", request.url)
-		servedETag = response.headers.get("ETag")
-		ETAGS.set(request.url, servedETag)
-		return response
-	}).catch(error => {
 			// console.log("Cache MISS:", request.url)
 			return refresh
 		})
 	
-	return evt.waitUntil(evt.respondWith(networkOrCache))
+		return evt.respondWith(networkOrCache)
-})
+	}
 
-self.addEventListener("push", (evt: PushEvent) => {
+	onMessage(evt: any) {
+		let message = JSON.parse(evt.data)
+	
+		let url = message.url
+		let refresh = RELOADS.get(url)
+		let servedETag = ETAGS.get(url)
+	
+		// If the user requests a sub-page we should prefetch the full page, too.
+		if(url.includes("/_/")) {
+			let fullPage = new Request(url.replace("/_/", "/"))
+	
+			let fullPageRefresh = fetch(fullPage, {
+				credentials: "same-origin"
+			}).then(response => {
+				// Save the new version of the resource in the cache
+				let cacheRefresh = caches.open(this.cache.version).then(cache => {
+					return cache.put(fullPage, response)
+				})
+	
+				CACHEREFRESH.set(fullPage.url, cacheRefresh)
+				return response
+			})
+
+			// Save in map
+			RELOADS.set(fullPage.url, fullPageRefresh)
+		}
+	
+		if(!refresh || !servedETag) {
+			return Promise.resolve()
+		}
+
+		return refresh.then((response: Response) => {
+			// If the fresh copy was used to serve the request instead of the cache,
+			// we don"t need to tell the client to do a refresh.
+			if(response.bodyUsed) {
+				return
+			}
+			
+			// Get ETag
+			let eTag = response.headers.get("ETag")
+
+			// Update ETag
+			ETAGS.set(url, eTag)
+
+			// Get CSP
+			let oldCSP = this.currentCSP
+			let csp = response.headers.get("Content-Security-Policy")
+
+			if(csp != oldCSP) {
+				this.currentCSP = csp
+
+				if(oldCSP !== "") {
+					return this.forceClientReloadPage(url, evt.source)
+				}
+			}
+
+			// If the ETag changed, we need to do a reload.
+			// If the CSP and therefore the sha-1 hash of the CSS changed, we need to do a reload.
+			if(eTag !== servedETag) {
+				return this.forceClientReloadContent(url, evt.source)
+			}
+			
+			// Do nothing
+			return Promise.resolve()
+		})
+	}
+
+	onPush(evt: PushEvent) {
 		var payload = evt.data ? evt.data.json() : {}
 	
-	evt.waitUntil(
+		return (self as any).registration.showNotification(payload.title, {
-		(self as any).registration.showNotification(payload.title, {
 			body: payload.message,
 			icon: payload.icon,
 			image: payload.image,
 			data: payload.link,
-			badge: "https://notify.moe/brand/64"
+			badge: "https://notify.moe/brand/64.png"
 		})
-	)
+	}
-})
 
-self.addEventListener("pushsubscriptionchange", (evt: any) => {
+	onPushSubscriptionChange(evt: any) {
-	evt.waitUntil((self as any).registration.pushManager.subscribe(evt.oldSubscription.options)
+		return (self as any).registration.pushManager.subscribe(evt.oldSubscription.options)
 		.then(async subscription => {
 			console.log("send subscription to server...")
 	
@@ -242,15 +260,14 @@ self.addEventListener("pushsubscriptionchange", (evt: any) => {
 				credentials: "same-origin",
 				body: JSON.stringify(pushSubscription)
 			})
-	}))
+		})
-})
+	}
 
-self.addEventListener("notificationclick", (evt: NotificationEvent) => {
+	onNotificationClick(evt: NotificationEvent) {
 		let notification = evt.notification
 		notification.close()
 	
-	evt.waitUntil(
+		return (self as any).clients.matchAll().then(function(clientList) {
-		(self as any).clients.matchAll().then(function(clientList) {
 			// If we have a link, use that link to open a new window.
 			let url = notification.data
 
@@ -266,21 +283,50 @@ self.addEventListener("notificationclick", (evt: NotificationEvent) => {
 			// Otherwise open a new window
 			return (self as any).clients.openWindow("https://notify.moe")
 		})
-	)
+	}
-})
 
-function installCache() {
+	forceClientReloadContent(url: string, eventSource: any) {
-	return caches.open(CACHE).then(cache => {
+		let message = {
+			type: "new content",
+			url
+		}
+
+		this.postMessageAfterPromise(message, CACHEREFRESH.get(url), eventSource)
+	}
+
+	forceClientReloadPage(url: string, eventSource: any) {
+		let message = {
+			type: "reload page",
+			url
+		}
+
+		this.postMessageAfterPromise(message, RELOADS.get(url.replace("/_/", "/")), eventSource)
+	}
+
+	postMessageAfterPromise(message: any, promise: Promise<any>, eventSource: any) {
+		if(!promise) {
+			console.log("forcing reload, cache refresh null")
+			return eventSource.postMessage(JSON.stringify(message))
+		}
+
+		return promise.then(() => {
+			console.log("forcing reload after cache refresh")
+			eventSource.postMessage(JSON.stringify(message))
+		})
+	}
+
+	installCache() {
+		return caches.open(this.cache.version).then(cache => {
 			return cache.addAll([
 				"./",
 				"./scripts",
 				"https://fonts.gstatic.com/s/ubuntu/v10/2Q-AW1e_taO6pHwMXcXW5w.ttf"
 			])
 		})
-}
+	}
 	
-function fromCache(request) {
+	fromCache(request) {
-	return caches.open(CACHE).then(cache => {
+		return caches.open(this.cache.version).then(cache => {
 			return cache.match(request).then(matching => {
 				if(matching) {
 					// console.log("Cache HIT:", request.url)
@@ -290,4 +336,7 @@ function fromCache(request) {
 				return Promise.reject("no-match")
 			})
 		})
+	}
 }
+
+const serviceWorker = new MyServiceWorker()