SEBWIN-183: Changed startup- and shutdown-controller to continue reverting operations, even if one or more of them fail.

SafeExamBrowser.Core.UnitTests/Behaviour/ShutdownControllerTests.cs

@@ -6,6 +6,7 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
  */
 
+using System;
 using System.Collections.Generic;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
 using Moq;
@@ -84,6 +85,29 @@ namespace SafeExamBrowser.Core.UnitTests.Behaviour
 			Assert.IsTrue(c == 3);
 		}
 
+		[TestMethod]
+		public void MustContinueToRevertOperationsInCaseOfError()
+		{
+			var operationA = new Mock<IOperation>();
+			var operationB = new Mock<IOperation>();
+			var operationC = new Mock<IOperation>();
+			var operations = new Queue<IOperation>();
+
+			operationA.Setup(o => o.Revert()).Throws<Exception>();
+			operationB.Setup(o => o.Revert()).Throws<Exception>();
+			operationC.Setup(o => o.Revert()).Throws<Exception>();
+
+			operations.Enqueue(operationA.Object);
+			operations.Enqueue(operationB.Object);
+			operations.Enqueue(operationC.Object);
+
+			sut.FinalizeApplication(operations);
+
+			operationA.Verify(o => o.Revert(), Times.Once);
+			operationB.Verify(o => o.Revert(), Times.Once);
+			operationC.Verify(o => o.Revert(), Times.Once);
+		}
+
 		[TestMethod]
 		public void MustNotFailWithEmptyQueue()
 		{

SafeExamBrowser.Core.UnitTests/Behaviour/StartupControllerTests.cs

@@ -149,6 +149,33 @@ namespace SafeExamBrowser.Core.UnitTests.Behaviour
 			Assert.IsTrue(a == 3);
 		}
 
+		[TestMethod]
+		public void MustContinueToRevertOperationsInCaseOfError()
+		{
+			var operationA = new Mock<IOperation>();
+			var operationB = new Mock<IOperation>();
+			var operationC = new Mock<IOperation>();
+			var operations = new Queue<IOperation>();
+
+			operationC.Setup(o => o.Perform()).Throws<Exception>();
+			operationC.Setup(o => o.Revert()).Throws<Exception>();
+			operationB.Setup(o => o.Revert()).Throws<Exception>();
+			operationA.Setup(o => o.Revert()).Throws<Exception>();
+
+			operations.Enqueue(operationA.Object);
+			operations.Enqueue(operationB.Object);
+			operations.Enqueue(operationC.Object);
+
+			var result = sut.TryInitializeApplication(operations);
+
+			operationA.Verify(o => o.Perform(), Times.Once);
+			operationA.Verify(o => o.Revert(), Times.Once);
+			operationB.Verify(o => o.Perform(), Times.Once);
+			operationB.Verify(o => o.Revert(), Times.Once);
+			operationC.Verify(o => o.Perform(), Times.Once);
+			operationC.Verify(o => o.Revert(), Times.Once);
+		}
+
 		[TestMethod]
 		public void MustSucceedWithEmptyQueue()
 		{

SafeExamBrowser.Core/Behaviour/ShutdownController.cs

@@ -52,8 +52,16 @@ namespace SafeExamBrowser.Core.Behaviour
 			foreach (var operation in operations)
 			{
 				operation.SplashScreen = splashScreen;
+
+				try
+				{
 					operation.Revert();
 				}
+				catch (Exception e)
+				{
+					logger.Error($"Failed to revert operation '{operation.GetType().Name}'!", e);
+				}
+			}
 		}
 
 		private void Initialize()

SafeExamBrowser.Core/Behaviour/StartupController.cs

@@ -77,7 +77,15 @@ namespace SafeExamBrowser.Core.Behaviour
 			{
 				var operation = stack.Pop();
 
+				try
+				{
 					operation.Revert();
+				}
+				catch (Exception e)
+				{
+					logger.Error($"Failed to revert operation '{operation.GetType().Name}'!", e);
+				}
+
 				splashScreen.Regress();
 			}
 		}

SafeExamBrowser.sln

@@ -1,7 +1,7 @@
 
 Microsoft Visual Studio Solution File, Format Version 12.00
 # Visual Studio 15
-VisualStudioVersion = 15.0.26730.8
+VisualStudioVersion = 15.0.26730.16
 MinimumVisualStudioVersion = 10.0.40219.1
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "SafeExamBrowser", "SafeExamBrowser\SafeExamBrowser.csproj", "{E3AED2F8-B5DF-45D1-AC19-48066923D6D8}"
 EndProject
@@ -10,7 +10,6 @@ EndProject
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Solution Items", "Solution Items", "{0A9E6674-2FB4-42EA-85DE-B2445B9AE2D9}"
 	ProjectSection(SolutionItems) = preProject
 		LICENSE.txt = LICENSE.txt
-		README.md = README.md
 	EndProjectSection
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "SafeExamBrowser.UserInterface.Windows10", "SafeExamBrowser.UserInterface.Windows10\SafeExamBrowser.UserInterface.Windows10.csproj", "{E1BE031A-4354-41E7-83E8-843DED4489FF}"

SafeExamBrowser/App.cs

@@ -8,6 +8,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.ComponentModel;
 using System.Linq;
 using System.Threading;
 using System.Windows;
@@ -65,7 +66,7 @@ namespace SafeExamBrowser
 			if (success)
 			{
 				MainWindow = instances.Taskbar;
-				MainWindow.Closing += (o, args) => ShutdownApplication();
+				MainWindow.Closing += MainWindow_Closing;
 				MainWindow.Show();
 			}
 			else
@@ -74,7 +75,7 @@ namespace SafeExamBrowser
 			}
 		}
 
-		private void ShutdownApplication()
+		private void MainWindow_Closing(object sender, CancelEventArgs e)
 		{
 			var operations = new Queue<IOperation>(instances.StartupOperations.Reverse());