Add more logging for BlazorWebView (#12357)

Fixes #9792

src/BlazorWebView/samples/BlazorWinFormsApp/BlazorWinFormsApp.csproj

@@ -15,6 +15,10 @@
     <ProjectReference Include="..\WebViewAppShared\WebViewAppShared.csproj" />
   </ItemGroup>
 
+  <ItemGroup>
+    <PackageReference Include="Microsoft.Extensions.Logging.Debug" />
+  </ItemGroup>
+
   <Import Project="..\..\src\WindowsForms\build\Microsoft.AspNetCore.Components.WebView.WindowsForms.targets" />
 
 </Project>

src/BlazorWebView/samples/BlazorWinFormsApp/Form1.cs

@@ -6,6 +6,7 @@
 using Microsoft.AspNetCore.Components.Web;
 using Microsoft.AspNetCore.Components.WebView.WindowsForms;
 using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Logging;
 using WebViewAppShared;
 
 namespace BlazorWinFormsApp
@@ -17,6 +18,12 @@ public partial class Form1 : Form
 		public Form1()
 		{
 			var services1 = new ServiceCollection();
+			services1.AddLogging(c =>
+			{
+				c.AddDebug();
+				// Enable maximum logging for BlazorWebView
+				c.AddFilter("Microsoft.AspNetCore.Components.WebView", LogLevel.Trace);
+			});
 			services1.AddWindowsFormsBlazorWebView();
 #if DEBUG
 			services1.AddBlazorWebViewDeveloperTools();

src/BlazorWebView/samples/BlazorWpfApp/BlazorWpfApp.csproj

@@ -15,6 +15,10 @@
     <ProjectReference Include="..\WebViewAppShared\WebViewAppShared.csproj" />
   </ItemGroup>
 
+  <ItemGroup>
+    <PackageReference Include="Microsoft.Extensions.Logging.Debug" />
+  </ItemGroup>
+
   <Import Project="..\..\src\Wpf\build\Microsoft.AspNetCore.Components.WebView.Wpf.targets" />
 
 </Project>

src/BlazorWebView/samples/BlazorWpfApp/MainWindow.xaml.cs

@@ -4,6 +4,7 @@
 using System.Windows;
 using Microsoft.AspNetCore.Components.Web;
 using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Logging;
 using WebViewAppShared;
 
 namespace BlazorWpfApp
@@ -18,6 +19,12 @@ public partial class MainWindow : Window
 		public MainWindow()
 		{
 			var services1 = new ServiceCollection();
+			services1.AddLogging(c =>
+			{
+				c.AddDebug();
+				// Enable maximum logging for BlazorWebView
+				c.AddFilter("Microsoft.AspNetCore.Components.WebView", LogLevel.Trace);
+			});
 			services1.AddWpfBlazorWebView();
 #if DEBUG
 			services1.AddBlazorWebViewDeveloperTools();

src/BlazorWebView/src/Maui/Android/AndroidWebKitWebViewManager.cs

@@ -2,11 +2,11 @@
 using System.Collections.Generic;
 using System.IO;
 using System.Runtime.Versioning;
-using System.Threading.Tasks;
 using Android.Webkit;
 using Microsoft.AspNetCore.Components.Web;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.FileProviders;
+using Microsoft.Extensions.Logging;
 using AUri = Android.Net.Uri;
 using AWebView = Android.Webkit.WebView;
 
@@ -25,6 +25,7 @@ internal class AndroidWebKitWebViewManager : WebViewManager
 		private static readonly string AppOrigin = $"https://{BlazorWebView.AppHostAddress}/";
 		private static readonly Uri AppOriginUri = new(AppOrigin);
 		private static readonly AUri AndroidAppOriginUri = AUri.Parse(AppOrigin)!;
+		private readonly ILogger _logger;
 		private readonly AWebView _webview;
 		private readonly string _contentRootRelativeToAppRoot;
 
@@ -37,7 +38,8 @@ internal class AndroidWebKitWebViewManager : WebViewManager
 		/// <param name="fileProvider">Provides static content to the webview.</param>
 		/// <param name="contentRootRelativeToAppRoot">Path to the directory containing application content files.</param>
 		/// <param name="hostPageRelativePath">Path to the host page within the <paramref name="fileProvider"/>.</param>
-		public AndroidWebKitWebViewManager(AWebView webview, IServiceProvider services, Dispatcher dispatcher, IFileProvider fileProvider, JSComponentConfigurationStore jsComponents, string contentRootRelativeToAppRoot, string hostPageRelativePath)
+		/// <param name="logger">Logger to send log messages to.</param>
+		public AndroidWebKitWebViewManager(AWebView webview, IServiceProvider services, Dispatcher dispatcher, IFileProvider fileProvider, JSComponentConfigurationStore jsComponents, string contentRootRelativeToAppRoot, string hostPageRelativePath, ILogger logger)
 			: base(services, dispatcher, AppOriginUri, fileProvider, jsComponents, hostPageRelativePath)
 		{
 			ArgumentNullException.ThrowIfNull(webview);
@@ -50,13 +52,16 @@ public AndroidWebKitWebViewManager(AWebView webview, IServiceProvider services,
 					$"Please add all the required services by calling '{nameof(IServiceCollection)}.{nameof(BlazorWebViewServiceCollectionExtensions.AddMauiBlazorWebView)}' in the application startup code.");
 			}
 #endif
+			_logger = logger;
+
 			_webview = webview;
 			_contentRootRelativeToAppRoot = contentRootRelativeToAppRoot;
 		}
 
 		/// <inheritdoc />
 		protected override void NavigateCore(Uri absoluteUri)
 		{
+			_logger.NavigatingToUri(absoluteUri);
 			_webview.LoadUrl(absoluteUri.AbsoluteUri);
 		}
 

src/BlazorWebView/src/Maui/Android/BlazorWebViewHandler.Android.cs

@@ -2,6 +2,8 @@
 using Android.Webkit;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.FileProviders;
+using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.Logging.Abstractions;
 using Microsoft.Maui;
 using Microsoft.Maui.Dispatching;
 using Microsoft.Maui.Handlers;
@@ -18,8 +20,13 @@ public partial class BlazorWebViewHandler : ViewHandler<IBlazorWebView, AWebView
 		private AndroidWebKitWebViewManager? _webviewManager;
 		internal AndroidWebKitWebViewManager? WebviewManager => _webviewManager;
 
+		private ILogger? _logger;
+		internal ILogger Logger => _logger ??= Services!.GetService<ILogger<BlazorWebViewHandler>>() ?? NullLogger<BlazorWebViewHandler>.Instance;
+
 		protected override AWebView CreatePlatformView()
 		{
+			Logger.CreatingAndroidWebkitWebView();
+
 #pragma warning disable CA1416, CA1412, CA1422 // Validate platform compatibility
 			var blazorAndroidWebView = new BlazorAndroidWebView(Context!)
 			{
@@ -46,6 +53,8 @@ protected override AWebView CreatePlatformView()
 			_webChromeClient = new BlazorWebChromeClient();
 			blazorAndroidWebView.SetWebChromeClient(_webChromeClient);
 
+			Logger.CreatedAndroidWebkitWebView();
+
 			return blazorAndroidWebView;
 		}
 
@@ -92,6 +101,8 @@ private void StartWebViewCoreIfPossible()
 			var contentRootDir = Path.GetDirectoryName(HostPage!) ?? string.Empty;
 			var hostPageRelativePath = Path.GetRelativePath(contentRootDir, HostPage!);
 
+			Logger.CreatingFileProvider(contentRootDir, hostPageRelativePath);
+
 			var fileProvider = VirtualView.CreateFileProvider(contentRootDir);
 
 			_webviewManager = new AndroidWebKitWebViewManager(
@@ -101,7 +112,8 @@ private void StartWebViewCoreIfPossible()
 				fileProvider,
 				VirtualView.JSComponents,
 				contentRootDir,
-				hostPageRelativePath);
+				hostPageRelativePath,
+				Logger);
 
 			StaticContentHotReloadManager.AttachToWebViewManagerIfEnabled(_webviewManager);
 
@@ -115,11 +127,14 @@ private void StartWebViewCoreIfPossible()
 			{
 				foreach (var rootComponent in RootComponents)
 				{
+					Logger.AddingRootComponent(rootComponent.ComponentType?.FullName ?? string.Empty, rootComponent.Selector ?? string.Empty, rootComponent.Parameters?.Count ?? 0);
+
 					// Since the page isn't loaded yet, this will always complete synchronously
 					_ = rootComponent.AddToWebViewManagerAsync(_webviewManager);
 				}
 			}
 
+			Logger.StartingInitialNavigation(VirtualView.StartPath);
 			_webviewManager.Navigate(VirtualView.StartPath);
 		}
 

src/BlazorWebView/src/Maui/Android/WebKitWebViewClient.cs

@@ -49,9 +49,11 @@ private bool ShouldOverrideUrlLoadingCore(IWebResourceRequest? request)
 			// so we know we can safely invoke the UrlLoading event.
 			var callbackArgs = UrlLoadingEventArgs.CreateWithDefaultLoadingStrategy(uri, AppOriginUri);
 			_webViewHandler.UrlLoading(callbackArgs);
+			_webViewHandler.Logger.NavigationEvent(uri, callbackArgs.UrlLoadingStrategy);
 
 			if (callbackArgs.UrlLoadingStrategy == UrlLoadingStrategy.OpenExternally)
 			{
+				_webViewHandler.Logger.LaunchExternalBrowser(uri);
 				try
 				{
 					var intent = Intent.ParseUri(uri.OriginalString, IntentUriType.Scheme);
@@ -84,15 +86,23 @@ private bool ShouldOverrideUrlLoadingCore(IWebResourceRequest? request)
 			var allowFallbackOnHostPage = AppOriginUri.IsBaseOfPage(requestUri);
 			requestUri = QueryStringHelper.RemovePossibleQueryString(requestUri);
 
+			_webViewHandler?.Logger.HandlingWebRequest(requestUri);
+
 			if (requestUri != null &&
 				_webViewHandler != null &&
 				_webViewHandler.WebviewManager != null &&
 				_webViewHandler.WebviewManager.TryGetResponseContentInternal(requestUri, allowFallbackOnHostPage, out var statusCode, out var statusMessage, out var content, out var headers))
 			{
 				var contentType = headers["Content-Type"];
 
+				_webViewHandler?.Logger.ResponseContentBeingSent(requestUri, statusCode);
+
 				return new WebResourceResponse(contentType, "UTF-8", statusCode, statusMessage, headers, content);
 			}
+			else
+			{
+				_webViewHandler?.Logger.ReponseContentNotFound(requestUri ?? string.Empty);
+			}
 
 			return base.ShouldInterceptRequest(view, request);
 		}
@@ -111,6 +121,8 @@ public override void OnPageFinished(AWebView? view, string? url)
 
 		private void RunBlazorStartupScripts(AWebView view)
 		{
+			_webViewHandler?.Logger.RunningBlazorStartupScripts();
+
 			// Confirm Blazor hasn't already initialized
 			view.EvaluateJavascript(@"
 				(function() { return typeof(window.__BlazorStarted); })();
@@ -171,6 +183,7 @@ private void RunBlazorStartupScripts(AWebView view)
 						", new JavaScriptValueCallback(_ =>
 						{
 							// Done; no more action required
+							_webViewHandler?.Logger.BlazorStartupScriptsFinished();
 						}));
 					}));
 			}));

src/BlazorWebView/src/Maui/Windows/BlazorWebViewHandler.Windows.cs

@@ -3,6 +3,8 @@
 using Microsoft.AspNetCore.Components.WebView.WebView2;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.FileProviders;
+using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.Logging.Abstractions;
 using Microsoft.Maui.Dispatching;
 using Microsoft.Maui.Handlers;
 using WebView2Control = Microsoft.UI.Xaml.Controls.WebView2;
@@ -56,11 +58,14 @@ private void StartWebViewCoreIfPossible()
 				throw new InvalidOperationException($"Can't start {nameof(BlazorWebView)} without native web view instance.");
 			}
 
+			var logger = Services!.GetService<ILogger<BlazorWebViewHandler>>() ?? NullLogger<BlazorWebViewHandler>.Instance;
+
 			// We assume the host page is always in the root of the content directory, because it's
 			// unclear there's any other use case. We can add more options later if so.
 			var contentRootDir = Path.GetDirectoryName(HostPage!) ?? string.Empty;
 			var hostPageRelativePath = Path.GetRelativePath(contentRootDir, HostPage!);
 
+			logger.CreatingFileProvider(contentRootDir, hostPageRelativePath);
 			var fileProvider = VirtualView.CreateFileProvider(contentRootDir);
 
 			_webviewManager = new WinUIWebViewManager(
@@ -71,18 +76,28 @@ private void StartWebViewCoreIfPossible()
 				VirtualView.JSComponents,
 				contentRootDir,
 				hostPageRelativePath,
-				this);
+				this,
+				logger);
 
 			StaticContentHotReloadManager.AttachToWebViewManagerIfEnabled(_webviewManager);
 
 			if (RootComponents != null)
 			{
 				foreach (var rootComponent in RootComponents)
 				{
+					if (rootComponent is null)
+					{
+						continue;
+					}
+
+					logger.AddingRootComponent(rootComponent.ComponentType?.FullName ?? string.Empty, rootComponent.Selector ?? string.Empty, rootComponent.Parameters?.Count ?? 0);
+
 					// Since the page isn't loaded yet, this will always complete synchronously
 					_ = rootComponent.AddToWebViewManagerAsync(_webviewManager);
 				}
 			}
+
+			logger.StartingInitialNavigation(VirtualView.StartPath);
 			_webviewManager.Navigate(VirtualView.StartPath);
 		}
 

src/BlazorWebView/src/Maui/Windows/WinUIWebViewManager.cs

@@ -5,6 +5,7 @@
 using Microsoft.AspNetCore.Components.Web;
 using Microsoft.AspNetCore.Components.WebView.WebView2;
 using Microsoft.Extensions.FileProviders;
+using Microsoft.Extensions.Logging;
 using Microsoft.Web.WebView2.Core;
 using Windows.ApplicationModel;
 using Windows.Storage.Streams;
@@ -22,6 +23,7 @@ internal class WinUIWebViewManager : WebView2WebViewManager
 		private readonly string _hostPageRelativePath;
 		private readonly string _contentRootRelativeToAppRoot;
 		private static readonly bool _isPackagedApp;
+		private readonly ILogger _logger;
 
 		static WinUIWebViewManager()
 		{
@@ -46,6 +48,7 @@ static WinUIWebViewManager()
 		/// <param name="contentRootRelativeToAppRoot">Path to the directory containing application content files.</param>
 		/// <param name="hostPagePathWithinFileProvider">Path to the host page within the <paramref name="fileProvider"/>.</param>
 		/// <param name="webViewHandler">The <see cref="BlazorWebViewHandler" />.</param>
+		/// <param name="logger">Logger to send log messages to.</param>
 		public WinUIWebViewManager(
 			WebView2Control webview,
 			IServiceProvider services,
@@ -54,9 +57,11 @@ public WinUIWebViewManager(
 			JSComponentConfigurationStore jsComponents,
 			string contentRootRelativeToAppRoot,
 			string hostPagePathWithinFileProvider,
-			BlazorWebViewHandler webViewHandler)
-			: base(webview, services, dispatcher, fileProvider, jsComponents, contentRootRelativeToAppRoot, hostPagePathWithinFileProvider, webViewHandler)
+			BlazorWebViewHandler webViewHandler,
+			ILogger logger)
+			: base(webview, services, dispatcher, fileProvider, jsComponents, contentRootRelativeToAppRoot, hostPagePathWithinFileProvider, webViewHandler, logger)
 		{
+			_logger = logger;
 			_webview = webview;
 			_hostPageRelativePath = hostPagePathWithinFileProvider;
 			_contentRootRelativeToAppRoot = contentRootRelativeToAppRoot;
@@ -77,13 +82,16 @@ protected override async Task HandleWebResourceRequest(CoreWebView2WebResourceRe
 
 			var requestUri = QueryStringHelper.RemovePossibleQueryString(eventArgs.Request.Uri);
 
+			_logger.HandlingWebRequest(requestUri);
+
 			// First, call into WebViewManager to see if it has a framework file for this request. It will
 			// fall back to an IFileProvider, but on WinUI it's always a NullFileProvider, so that will never
 			// return a file.
 			if (TryGetResponseContent(requestUri, allowFallbackOnHostPage, out var statusCode, out var statusMessage, out var content, out var headers)
 				&& statusCode != 404)
 			{
 				var headerString = GetHeaderString(headers);
+				_logger.ResponseContentBeingSent(requestUri, statusCode);
 				eventArgs.Response = _coreWebView2Environment!.CreateWebResourceResponse(content.AsRandomAccessStream(), statusCode, statusMessage, headerString);
 			}
 			else if (new Uri(requestUri) is Uri uri && AppOriginUri.IsBaseOf(uri))
@@ -130,12 +138,19 @@ protected override async Task HandleWebResourceRequest(CoreWebView2WebResourceRe
 				if (stream != null)
 				{
 					var headerString = GetHeaderString(headers);
+
+					_logger.ResponseContentBeingSent(requestUri, statusCode);
+
 					eventArgs.Response = _coreWebView2Environment!.CreateWebResourceResponse(
 						stream,
 						statusCode,
 						statusMessage,
 						headerString);
 				}
+				else
+				{
+					_logger.ReponseContentNotFound(requestUri);
+				}
 
 				async Task<IRandomAccessStream> CopyContentToRandomAccessStreamAsync(Stream content)
 				{
@@ -157,6 +172,8 @@ protected override void QueueBlazorStart()
 			// In .NET MAUI we use autostart='false' for the Blazor script reference, so we start it up manually in this event
 			_webview.CoreWebView2.DOMContentLoaded += async (_, __) =>
 			{
+				_logger.CallingBlazorStart();
+
 				await _webview.CoreWebView2!.ExecuteScriptAsync(@"
 					Blazor.start();
 					");