SEBWIN-220: Implemented basic logging for browser modules.

SafeExamBrowser.Browser/BrowserApplicationController.cs

@@ -10,9 +10,9 @@ using System;
 using System.Collections.Generic;
 using System.Linq;
 using CefSharp;
-using SafeExamBrowser.Contracts.Core;
 using SafeExamBrowser.Contracts.Browser;
 using SafeExamBrowser.Contracts.Configuration;
+using SafeExamBrowser.Contracts.Core;
 using SafeExamBrowser.Contracts.I18n;
 using SafeExamBrowser.Contracts.Logging;
 using SafeExamBrowser.Contracts.UserInterface;
@@ -29,7 +29,7 @@ namespace SafeExamBrowser.Browser
 		private AppConfig appConfig;
 		private IApplicationButton button;
 		private IList<IApplicationInstance> instances;
-		private ILogger logger;
+		private IModuleLogger logger;
 		private IMessageBox messageBox;
 		private BrowserSettings settings;
 		private IText text;
@@ -40,7 +40,7 @@ namespace SafeExamBrowser.Browser
 		public BrowserApplicationController(
 			AppConfig appConfig,
 			BrowserSettings settings,
-			ILogger logger,
+			IModuleLogger logger,
 			IMessageBox messageBox,
 			IText text,
 			IUserInterfaceFactory uiFactory)
@@ -92,7 +92,8 @@ namespace SafeExamBrowser.Browser
 		{
 			var id = new BrowserInstanceIdentifier(++instanceIdCounter);
 			var isMainInstance = instances.Count == 0;
-			var instance = new BrowserApplicationInstance(appConfig, settings, id, isMainInstance, text, uiFactory);
+			var instanceLogger = logger.CloneFor($"BrowserInstance {id}");
+			var instance = new BrowserApplicationInstance(appConfig, settings, id, isMainInstance, instanceLogger, text, uiFactory);
 
 			instance.Initialize();
 			instance.ConfigurationDownloadRequested += (fileName, args) => ConfigurationDownloadRequested?.Invoke(fileName, args);

SafeExamBrowser.Browser/BrowserApplicationInstance.cs

@@ -7,12 +7,13 @@
  */
 
 using SafeExamBrowser.Browser.Handlers;
-using SafeExamBrowser.Contracts.Core;
-using SafeExamBrowser.Contracts.Core.Events;
 using SafeExamBrowser.Contracts.Browser;
 using SafeExamBrowser.Contracts.Configuration;
 using SafeExamBrowser.Contracts.Configuration.Settings;
+using SafeExamBrowser.Contracts.Core;
+using SafeExamBrowser.Contracts.Core.Events;
 using SafeExamBrowser.Contracts.I18n;
+using SafeExamBrowser.Contracts.Logging;
 using SafeExamBrowser.Contracts.UserInterface;
 using SafeExamBrowser.Contracts.UserInterface.Browser;
 using SafeExamBrowser.Contracts.UserInterface.Windows;
@@ -25,6 +26,7 @@ namespace SafeExamBrowser.Browser
 		private IBrowserControl control;
 		private IBrowserWindow window;
 		private bool isMainInstance;
+		private IModuleLogger logger;
 		private BrowserSettings settings;
 		private IText text;
 		private IUserInterfaceFactory uiFactory;
@@ -42,12 +44,14 @@ namespace SafeExamBrowser.Browser
 			BrowserSettings settings,
 			InstanceIdentifier id,
 			bool isMainInstance,
+			IModuleLogger logger,
 			IText text,
 			IUserInterfaceFactory uiFactory)
 		{
 			this.appConfig = appConfig;
 			this.Id = id;
 			this.isMainInstance = isMainInstance;
+			this.logger = logger;
 			this.settings = settings;
 			this.text = text;
 			this.uiFactory = uiFactory;
@@ -55,17 +59,21 @@ namespace SafeExamBrowser.Browser
 
 		internal void Initialize()
 		{
-			var downloadHandler = new DownloadHandler(appConfig, settings);
+			var controlLogger = logger.CloneFor($"{nameof(BrowserControl)} {Id}");
+			var downloadLogger = logger.CloneFor($"{nameof(DownloadHandler)} {Id}");
+			var downloadHandler = new DownloadHandler(appConfig, settings, downloadLogger);
 
 			downloadHandler.ConfigurationDownloadRequested += (fileName, args) => ConfigurationDownloadRequested?.Invoke(fileName, args);
 
-			control = new BrowserControl(appConfig, settings, text);
+			control = new BrowserControl(appConfig, settings, controlLogger, text);
 			control.AddressChanged += Control_AddressChanged;
 			control.LoadingStateChanged += Control_LoadingStateChanged;
 			control.TitleChanged += Control_TitleChanged;
 			(control as BrowserControl).DownloadHandler = downloadHandler;
 			(control as BrowserControl).Initialize();
 
+			logger.Debug("Initialized browser control.");
+
 			window = uiFactory.CreateBrowserWindow(control, settings);
 			window.IsMainWindow = isMainInstance;
 			window.Closing += () => Terminated?.Invoke(Id);
@@ -73,6 +81,8 @@ namespace SafeExamBrowser.Browser
 			window.ReloadRequested += Window_ReloadRequested;
 			window.BackwardNavigationRequested += Window_BackwardNavigationRequested;
 			window.ForwardNavigationRequested += Window_ForwardNavigationRequested;
+
+			logger.Debug("Initialized browser window.");
 		}
 
 		private void Control_AddressChanged(string address)
@@ -93,21 +103,25 @@ namespace SafeExamBrowser.Browser
 
 		private void Window_AddressChanged(string address)
 		{
+			logger.Debug($"The user requested to navigate to '{address}'.");
 			control.NavigateTo(address);
 		}
 
 		private void Window_ReloadRequested()
 		{
+			logger.Debug($"The user requested to reload the current page.");
 			control.Reload();
 		}
 
 		private void Window_BackwardNavigationRequested()
 		{
+			logger.Debug($"The user requested to navigate backwards.");
 			control.NavigateBackwards();
 		}
 
 		private void Window_ForwardNavigationRequested()
 		{
+			logger.Debug($"The user requested to navigate forwards.");
 			control.NavigateForwards();
 		}
 	}

SafeExamBrowser.Browser/BrowserControl.cs

@@ -7,10 +7,12 @@
  */
 
 using System;
+using CefSharp;
 using CefSharp.WinForms;
 using SafeExamBrowser.Browser.Handlers;
 using SafeExamBrowser.Contracts.Configuration;
 using SafeExamBrowser.Contracts.I18n;
+using SafeExamBrowser.Contracts.Logging;
 using SafeExamBrowser.Contracts.UserInterface.Browser;
 using SafeExamBrowser.Contracts.UserInterface.Browser.Events;
 using BrowserSettings = SafeExamBrowser.Contracts.Configuration.Settings.BrowserSettings;
@@ -21,6 +23,7 @@ namespace SafeExamBrowser.Browser
 	{
 		private AppConfig appConfig;
 		private BrowserSettings settings;
+		private ILogger logger;
 		private IText text;
 
 		private AddressChangedEventHandler addressChanged;
@@ -45,16 +48,17 @@ namespace SafeExamBrowser.Browser
 			remove { titleChanged -= value; }
 		}
 
-		public BrowserControl(AppConfig appConfig, BrowserSettings settings, IText text) : base(settings.StartUrl)
+		public BrowserControl(AppConfig appConfig, BrowserSettings settings, ILogger logger, IText text) : base(settings.StartUrl)
 		{
 			this.appConfig = appConfig;
+			this.logger = logger;
 			this.settings = settings;
 			this.text = text;
 		}
 
 		public void Initialize()
 		{
-			AddressChanged += (o, args) => addressChanged?.Invoke(args.Address);
+			AddressChanged += BrowserControl_AddressChanged;
 			LoadingStateChanged += (o, args) => loadingStateChanged?.Invoke(args.IsLoading);
 			TitleChanged += (o, args) => titleChanged?.Invoke(args.Title);
 
@@ -62,7 +66,7 @@ namespace SafeExamBrowser.Browser
 			MenuHandler = new ContextMenuHandler(settings, text);
 			RequestHandler = new RequestHandler(appConfig);
 		}
-		
+
 		public void NavigateBackwards()
 		{
 			GetBrowser().GoBack();
@@ -85,5 +89,11 @@ namespace SafeExamBrowser.Browser
 		{
 			GetBrowser().Reload();
 		}
+
+		private void BrowserControl_AddressChanged(object sender, AddressChangedEventArgs args)
+		{
+			logger.Debug($"Navigated to '{args.Address}'.");
+			addressChanged?.Invoke(args.Address);
+		}
 	}
 }

SafeExamBrowser.Browser/Handlers/DownloadHandler.cs

@@ -13,6 +13,7 @@ using System.Threading.Tasks;
 using CefSharp;
 using SafeExamBrowser.Contracts.Browser;
 using SafeExamBrowser.Contracts.Configuration;
+using SafeExamBrowser.Contracts.Logging;
 using BrowserSettings = SafeExamBrowser.Contracts.Configuration.Settings.BrowserSettings;
 
 namespace SafeExamBrowser.Browser.Handlers
@@ -25,13 +26,15 @@ namespace SafeExamBrowser.Browser.Handlers
 		private AppConfig appConfig;
 		private BrowserSettings settings;
 		private ConcurrentDictionary<int, DownloadFinishedCallback> callbacks;
+		private ILogger logger;
 
 		public event DownloadRequestedEventHandler ConfigurationDownloadRequested;
 
-		public DownloadHandler(AppConfig appConfig, BrowserSettings settings)
+		public DownloadHandler(AppConfig appConfig, BrowserSettings settings, ILogger logger)
 		{
 			this.appConfig = appConfig;
 			this.callbacks = new ConcurrentDictionary<int, DownloadFinishedCallback>();
+			this.logger = logger;
 			this.settings = settings;
 		}
 
@@ -41,17 +44,25 @@ namespace SafeExamBrowser.Browser.Handlers
 			var extension = Path.GetExtension(uri.AbsolutePath);
 			var isConfigFile = String.Equals(extension, appConfig.ConfigurationFileExtension, StringComparison.InvariantCultureIgnoreCase);
 
+			logger.Debug($"Handling download request for '{uri}'.");
+
 			if (isConfigFile)
 			{
 				Task.Run(() => RequestConfigurationFileDownload(downloadItem, callback));
 			}
-			else if (!isConfigFile && settings.AllowDownloads)
+			else if (settings.AllowDownloads)
 			{
+				logger.Debug($"Starting download of '{uri}'...");
+
 				using (callback)
 				{
 					callback.Continue(null, true);
 				}
 			}
+			else
+			{
+				logger.Info($"Aborted download request for '{uri}', as downloading is not allowed.");
+			}
 		}
 
 		public void OnDownloadUpdated(IBrowser browser, DownloadItem downloadItem, IDownloadItemCallback callback)
@@ -62,6 +73,8 @@ namespace SafeExamBrowser.Browser.Handlers
 				{
 					Task.Run(() => finished.Invoke(downloadItem.IsComplete, downloadItem.FullPath));
 				}
+
+				logger.Debug($"Download of '{downloadItem.Url}' {(downloadItem.IsComplete ? "is complete" : "was cancelled")}.");
 			}
 		}
 
@@ -70,6 +83,7 @@ namespace SafeExamBrowser.Browser.Handlers
 			var args = new DownloadEventArgs();
 
 			ConfigurationDownloadRequested?.Invoke(downloadItem.SuggestedFileName, args);
+			logger.Debug($"Download of configuration file '{downloadItem.Url}' was {(args.AllowDownload ? "granted" : "denied")}.");
 
 			if (args.AllowDownload)
 			{

SafeExamBrowser.Client/CompositionRoot.cs

@@ -80,15 +80,15 @@ namespace SafeExamBrowser.Client
 			InitializeText();
 
 			messageBox = new MessageBox(text);
-			processMonitor = new ProcessMonitor(new ModuleLogger(logger, typeof(ProcessMonitor)), nativeMethods);
+			processMonitor = new ProcessMonitor(new ModuleLogger(logger, nameof(ProcessMonitor)), nativeMethods);
 			uiFactory = new UserInterfaceFactory(text);
-			runtimeProxy = new RuntimeProxy(runtimeHostUri, new ProxyObjectFactory(), new ModuleLogger(logger, typeof(RuntimeProxy)));
+			runtimeProxy = new RuntimeProxy(runtimeHostUri, new ProxyObjectFactory(), new ModuleLogger(logger, nameof(RuntimeProxy)));
 
-			var displayMonitor = new DisplayMonitor(new ModuleLogger(logger, typeof(DisplayMonitor)), nativeMethods);
+			var displayMonitor = new DisplayMonitor(new ModuleLogger(logger, nameof(DisplayMonitor)), nativeMethods);
-			var explorerShell = new ExplorerShell(new ModuleLogger(logger, typeof(ExplorerShell)), nativeMethods);
+			var explorerShell = new ExplorerShell(new ModuleLogger(logger, nameof(ExplorerShell)), nativeMethods);
-			var windowMonitor = new WindowMonitor(new ModuleLogger(logger, typeof(WindowMonitor)), nativeMethods);
+			var windowMonitor = new WindowMonitor(new ModuleLogger(logger, nameof(WindowMonitor)), nativeMethods);
 
-			Taskbar = new Taskbar(new ModuleLogger(logger, typeof(Taskbar)));
+			Taskbar = new Taskbar(new ModuleLogger(logger, nameof(Taskbar)));
 
 			var operations = new Queue<IOperation>();
 
@@ -181,7 +181,7 @@ namespace SafeExamBrowser.Client
 		{
 			var processId = Process.GetCurrentProcess().Id;
 			var factory = new HostObjectFactory();
-			var host = new ClientHost(configuration.AppConfig.ClientAddress, factory, new ModuleLogger(logger, typeof(ClientHost)), processId);
+			var host = new ClientHost(configuration.AppConfig.ClientAddress, factory, new ModuleLogger(logger, nameof(ClientHost)), processId);
 			var operation = new CommunicationOperation(host, logger);
 
 			clientHost = host;
@@ -192,7 +192,7 @@ namespace SafeExamBrowser.Client
 
 		private IOperation BuildKeyboardInterceptorOperation()
 		{
-			var keyboardInterceptor = new KeyboardInterceptor(configuration.Settings.Keyboard, new ModuleLogger(logger, typeof(KeyboardInterceptor)));
+			var keyboardInterceptor = new KeyboardInterceptor(configuration.Settings.Keyboard, new ModuleLogger(logger, nameof(KeyboardInterceptor)));
 			var operation = new KeyboardInterceptorOperation(keyboardInterceptor, logger, nativeMethods);
 
 			return operation;
@@ -200,7 +200,7 @@ namespace SafeExamBrowser.Client
 
 		private IOperation BuildMouseInterceptorOperation()
 		{
-			var mouseInterceptor = new MouseInterceptor(new ModuleLogger(logger, typeof(MouseInterceptor)), configuration.Settings.Mouse);
+			var mouseInterceptor = new MouseInterceptor(new ModuleLogger(logger, nameof(MouseInterceptor)), configuration.Settings.Mouse);
 			var operation = new MouseInterceptorOperation(logger, mouseInterceptor, nativeMethods);
 
 			return operation;
@@ -213,11 +213,11 @@ namespace SafeExamBrowser.Client
 
 		private IOperation BuildTaskbarOperation()
 		{
-			var keyboardLayout = new KeyboardLayout(new ModuleLogger(logger, typeof(KeyboardLayout)), text);
+			var keyboardLayout = new KeyboardLayout(new ModuleLogger(logger, nameof(KeyboardLayout)), text);
 			var logController = new LogNotificationController(logger, uiFactory);
 			var logInfo = new LogNotificationInfo(text);
-			var powerSupply = new PowerSupply(new ModuleLogger(logger, typeof(PowerSupply)), text);
+			var powerSupply = new PowerSupply(new ModuleLogger(logger, nameof(PowerSupply)), text);
-			var wirelessNetwork = new WirelessNetwork(new ModuleLogger(logger, typeof(WirelessNetwork)), text);
+			var wirelessNetwork = new WirelessNetwork(new ModuleLogger(logger, nameof(WirelessNetwork)), text);
 			var operation = new TaskbarOperation(logger, logInfo, logController, keyboardLayout, powerSupply, wirelessNetwork, systemInfo, Taskbar, configuration.Settings.Taskbar, text, uiFactory);
 
 			return operation;

SafeExamBrowser.Contracts/Logging/IModuleLogger.cs

@@ -0,0 +1,21 @@
+/*
+ * Copyright (c) 2018 ETH Zürich, Educational Development and Technology (LET)
+ * 
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+namespace SafeExamBrowser.Contracts.Logging
+{
+	/// <summary>
+	/// An implementation of <see cref="ILogger"/> which automatically appends information about the module from which messages are logged.
+	/// </summary>
+	public interface IModuleLogger : ILogger
+	{
+		/// <summary>
+		/// Creates a new instance which will automatically append the given module information.
+		/// </summary>
+		IModuleLogger CloneFor(string moduleInfo);
+	}
+}

SafeExamBrowser.Contracts/SafeExamBrowser.Contracts.csproj

@@ -129,6 +129,7 @@
     <Compile Include="Logging\ILogMessage.cs" />
     <Compile Include="Logging\ILogObserver.cs" />
     <Compile Include="Logging\ILogText.cs" />
+    <Compile Include="Logging\IModuleLogger.cs" />
     <Compile Include="Logging\IThreadInfo.cs" />
     <Compile Include="Logging\LogLevel.cs" />
     <Compile Include="Monitoring\Events\DisplayChangedEventHandler.cs" />

SafeExamBrowser.Logging.UnitTests/ModuleLoggerTests.cs

@@ -10,13 +10,26 @@ using System;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
 using Moq;
 using SafeExamBrowser.Contracts.Logging;
-using SafeExamBrowser.Logging;
 
 namespace SafeExamBrowser.Logging.UnitTests
 {
 	[TestClass]
 	public class ModuleLoggerTests
 	{
+		[TestMethod]
+		public void MustCorrectlyClone()
+		{
+			var loggerMock = new Mock<ILogger>();
+			var sut = new ModuleLogger(loggerMock.Object, nameof(ModuleLoggerTests));
+			var clone = sut.CloneFor("blubb");
+
+			sut.Debug("Debug");
+			clone.Debug("Debug");
+
+			loggerMock.Verify(l => l.Debug($"[{nameof(ModuleLoggerTests)}] Debug"), Times.Once);
+			loggerMock.Verify(l => l.Debug($"[blubb] Debug"), Times.Once);
+		}
+
 		[TestMethod]
 		public void MustCorrectlyForwardCalls()
 		{
@@ -24,7 +37,7 @@ namespace SafeExamBrowser.Logging.UnitTests
 			var loggerMock = new Mock<ILogger>();
 			var logObserverMock = new Mock<ILogObserver>();
 			var logText = new LogText("Log text");
-			var sut = new ModuleLogger(loggerMock.Object, typeof(ModuleLoggerTests));
+			var sut = new ModuleLogger(loggerMock.Object, nameof(ModuleLoggerTests));
 
 			sut.Debug("Debug");
 			sut.Info("Info");

SafeExamBrowser.Logging/ModuleLogger.cs

@@ -12,10 +12,7 @@ using SafeExamBrowser.Contracts.Logging;
 
 namespace SafeExamBrowser.Logging
 {
-	/// <summary>
+	public class ModuleLogger : IModuleLogger
-	/// Wraps an implementation of <see cref="ILogger"/> in order to append information about the module from which messages are logged.
-	/// </summary>
-	public class ModuleLogger : ILogger
 	{
 		private ILogger logger;
 		private string moduleInfo;
@@ -26,8 +23,9 @@ namespace SafeExamBrowser.Logging
 			this.moduleInfo = moduleInfo;
 		}
 
-		public ModuleLogger(ILogger logger, Type module) : this(logger, module.Name)
+		public IModuleLogger CloneFor(string moduleInfo)
 		{
+			return new ModuleLogger(logger, moduleInfo);
 		}
 
 		public void Debug(string message)

SafeExamBrowser.Runtime/Communication/ProxyFactory.cs

@@ -26,7 +26,7 @@ namespace SafeExamBrowser.Runtime.Communication
 
 		public IClientProxy CreateClientProxy(string address)
 		{
-			return new ClientProxy(address, factory, new ModuleLogger(logger, typeof(ClientProxy)));
+			return new ClientProxy(address, factory, new ModuleLogger(logger, nameof(ClientProxy)));
 		}
 	}
 }

SafeExamBrowser.Runtime/CompositionRoot.cs

@@ -55,13 +55,13 @@ namespace SafeExamBrowser.Runtime
 			InitializeText();
 
 			var messageBox = new MessageBox(text);
-			var desktopFactory = new DesktopFactory(new ModuleLogger(logger, typeof(DesktopFactory)));
+			var desktopFactory = new DesktopFactory(new ModuleLogger(logger, nameof(DesktopFactory)));
-			var explorerShell = new ExplorerShell(new ModuleLogger(logger, typeof(ExplorerShell)), nativeMethods);
+			var explorerShell = new ExplorerShell(new ModuleLogger(logger, nameof(ExplorerShell)), nativeMethods);
-			var processFactory = new ProcessFactory(new ModuleLogger(logger, typeof(ProcessFactory)));
+			var processFactory = new ProcessFactory(new ModuleLogger(logger, nameof(ProcessFactory)));
 			var proxyFactory = new ProxyFactory(new ProxyObjectFactory(), logger);
 			var resourceLoader = new ResourceLoader();
-			var runtimeHost = new RuntimeHost(appConfig.RuntimeAddress, configuration, new HostObjectFactory(), new ModuleLogger(logger, typeof(RuntimeHost)));
+			var runtimeHost = new RuntimeHost(appConfig.RuntimeAddress, configuration, new HostObjectFactory(), new ModuleLogger(logger, nameof(RuntimeHost)));
-			var serviceProxy = new ServiceProxy(appConfig.ServiceAddress, new ProxyObjectFactory(), new ModuleLogger(logger, typeof(ServiceProxy)));
+			var serviceProxy = new ServiceProxy(appConfig.ServiceAddress, new ProxyObjectFactory(), new ModuleLogger(logger, nameof(ServiceProxy)));
 			var uiFactory = new UserInterfaceFactory(text);
 
 			var bootstrapOperations = new Queue<IOperation>();