feat: PWA update strategy with hashed assets and cache control

Move frontend sources to frontend/, build content-hashed assets at deploy, network-first SW for shell/JS, immutable cache for /assets/, version.json update banner, and Cache-Control middleware. Docs in docs/PWA-STRATEGY.md. Co-authored-by: Cursor <cursoragent@cursor.com>
2026-07-08 08:51:12 +02:00
parent bff14167c9
commit 7cec3030c1
29 changed files with 779 additions and 61 deletions
@@ -0,0 +1,69 @@
+let deferredInstallPrompt = null;
+
+function isStandalone() {
+  return window.matchMedia("(display-mode: standalone)").matches || window.navigator.standalone === true;
+}
+
+export function wirePwaInstall({ sectionId = "pwaInstallSection", buttonId = "installPwa" } = {}) {
+  const section = document.getElementById(sectionId);
+  const button = document.getElementById(buttonId);
+  if (!section || !button) return;
+
+  const hide = () => { section.hidden = true; };
+  if (isStandalone()) { hide(); return; }
+  hide();
+
+  window.addEventListener("beforeinstallprompt", (e) => {
+    e.preventDefault();
+    deferredInstallPrompt = e;
+    section.hidden = false;
+  });
+
+  window.addEventListener("appinstalled", () => {
+    deferredInstallPrompt = null;
+    hide();
+  });
+
+  button.addEventListener("click", async () => {
+    if (!deferredInstallPrompt) return;
+    deferredInstallPrompt.prompt();
+    await deferredInstallPrompt.userChoice;
+    deferredInstallPrompt = null;
+    hide();
+  });
+}
+
+export async function registerPwa() {
+  if (!("serviceWorker" in navigator)) return;
+  try {
+    const reg = await navigator.serviceWorker.register("/sw.js");
+    if ("sync" in ServiceWorkerRegistration.prototype) {
+      navigator.serviceWorker.ready.then((readyReg) => {
+        readyReg.sync?.register("sync-logs").catch(() => {});
+      });
+    }
+    return reg;
+  } catch (e) {
+    console.error("SW registration failed:", e);
+  }
+}
+
+export async function subscribePush(vapidPublicKey) {
+  if (!("PushManager" in window)) throw new Error("Push nicht unterstützt");
+  const reg = await navigator.serviceWorker.ready;
+  let sub = await reg.pushManager.getSubscription();
+  if (!sub) {
+    sub = await reg.pushManager.subscribe({
+      userVisibleOnly: true,
+      applicationServerKey: urlBase64ToUint8Array(vapidPublicKey),
+    });
+  }
+  return sub.toJSON();
+}
+
+function urlBase64ToUint8Array(base64String) {
+  const padding = "=".repeat((4 - (base64String.length % 4)) % 4);
+  const base64 = (base64String + padding).replace(/-/g, "+").replace(/_/g, "/");
+  const raw = atob(base64);
+  return Uint8Array.from([...raw].map((c) => c.charCodeAt(0)));
+}