Enhance bit Boilerplate Bswup update (#11159)

src/Templates/Boilerplate/Bit.Boilerplate/src/Client/Boilerplate.Client.Core/Scripts/app.ts

@@ -74,16 +74,6 @@ class App {
         };
     };
     //#endif
-
-    public static async forceUpdate() {
-        const bswup = (window as any).BitBswup;
-        const bswupProgress = (window as any).BitBswupProgress;
-
-        if (await bswup.skipWaiting()) return;
-
-        bswupProgress.config({ autoReload: true });
-        bswup.checkForUpdate();
-    }
 }
 
 (window as any).App = App;

src/Templates/Boilerplate/Bit.Boilerplate/src/Client/Boilerplate.Client.Core/Scripts/bswup.ts

@@ -0,0 +1,33 @@
+/**
+ * Checks for and applies updates if available.
+ * Called by `WebAppUpdateService.cs` when the user clicks the app version in `AppShell.razor`
+ * or when `ForceUpdateSnackbar.razor` appears after a forced update.
+ */
+async function tryUpdatePwa(autoReload?: boolean) {
+    const bswup = (window as any).BitBswup; // https://bitplatform.dev/bswup
+    const bswupProgress = (window as any).BitBswupProgress;
+
+    if (await bswup.skipWaiting()) return;
+
+    bswupProgress.config({ autoReload: autoReload ?? true });
+    bswup.checkForUpdate();
+}
+
+// To minimize user-facing force updates, the following code attempts to update the PWA ASAP.
+window.addEventListener('beforeunload', () => tryUpdatePwa(true));
+
+let appIsInBackground = false; // App is in the background if visibilityState is 'hidden' for 20 seconds.
+let visibilityChangeTimeout: number;
+window.addEventListener('visibilitychange', () => {
+    if (document.visibilityState === 'hidden') {
+        visibilityChangeTimeout = window.setTimeout(() => {
+            appIsInBackground = true;
+        }, 20 * 1000 /* 20 seconds */);
+    } else {
+        clearTimeout(visibilityChangeTimeout);
+        appIsInBackground = false;
+    }
+});
+
+// This would download the updates, but reloads the app only if it's in the background.
+setInterval(() => tryUpdatePwa(appIsInBackground), 60 * 1000 /* 1 minute */);

src/Templates/Boilerplate/Bit.Boilerplate/src/Client/Boilerplate.Client.Web/Services/WebAppUpdateService.cs

@@ -7,6 +7,6 @@ public partial class WebAppUpdateService : IAppUpdateService
 
     public async Task ForceUpdate()
     {
-        await jsRuntime.InvokeVoidAsync("tryUpdatingPWA");
+        await jsRuntime.InvokeVoidAsync("tryUpdatePwa");
     }
 }