SEBWIN-219: Extended unit tests for BaseProxy.

SafeExamBrowser.Core.UnitTests/Communication/BaseProxyImpl.cs

@@ -35,5 +35,30 @@ namespace SafeExamBrowser.Core.UnitTests.Communication
 		{
 			return base.Send(message);
 		}
+
+		public new Response Send(SimpleMessagePurport purport)
+		{
+			return base.Send(purport);
+		}
+
+		public new bool IsAcknowledged(Response response)
+		{
+			return base.IsAcknowledged(response);
+		}
+
+		public new void TestConnection()
+		{
+			base.TestConnection();
+		}
+
+		public new string ToString(Message message)
+		{
+			return base.ToString(message);
+		}
+
+		public new string ToString(Response response)
+		{
+			return base.ToString(response);
+		}
 	}
 }

SafeExamBrowser.Core.UnitTests/Communication/BaseProxyTests.cs

@@ -14,7 +14,6 @@ using SafeExamBrowser.Contracts.Communication;
 using SafeExamBrowser.Contracts.Communication.Messages;
 using SafeExamBrowser.Contracts.Communication.Responses;
 using SafeExamBrowser.Contracts.Logging;
-using SafeExamBrowser.Core.Communication;
 
 namespace SafeExamBrowser.Core.UnitTests.Communication
 {
@@ -23,7 +22,7 @@ namespace SafeExamBrowser.Core.UnitTests.Communication
 	{
 		private Mock<IProxyObjectFactory> proxyObjectFactory;
 		private Mock<ILogger> logger;
-		private BaseProxy sut;
+		private BaseProxyImpl sut;
 
 		[TestInitialize]
 		public void Initialize()
@@ -139,7 +138,7 @@ namespace SafeExamBrowser.Core.UnitTests.Communication
 		[ExpectedException(typeof(InvalidOperationException))]
 		public void MustFailToSendIfNotConnected()
 		{
-			(sut as BaseProxyImpl).Send(new Mock<Message>().Object);
+			sut.Send(new Mock<Message>().Object);
 		}
 
 		[TestMethod]
@@ -160,14 +159,14 @@ namespace SafeExamBrowser.Core.UnitTests.Communication
 			var token = Guid.NewGuid();
 
 			sut.Connect(token);
-			(sut as BaseProxyImpl).Send(new Mock<Message>().Object);
+			sut.Send(new Mock<Message>().Object);
 		}
 
 		[TestMethod]
 		[ExpectedException(typeof(ArgumentNullException))]
 		public void MustNotAllowSendingNull()
 		{
-			(sut as BaseProxyImpl).Send(null);
+			sut.Send(null);
 		}
 
 		[TestMethod]
@@ -189,10 +188,143 @@ namespace SafeExamBrowser.Core.UnitTests.Communication
 
 			var token = Guid.NewGuid();
 			var connected = sut.Connect(token);
-			var received = (sut as BaseProxyImpl).Send(message);
+			var received = sut.Send(message);
 
 			Assert.AreEqual(response.Object, received);
 			Assert.AreEqual(connectionResponse.CommunicationToken, message.CommunicationToken);
 		}
+
+		[TestMethod]
+		public void MustSendSimpleMessageCorrectly()
+		{
+			var proxy = new Mock<ICommunication>();
+			var connectionResponse = new ConnectionResponse
+			{
+				CommunicationToken = Guid.NewGuid(),
+				ConnectionEstablished = true
+			};
+			var purport = SimpleMessagePurport.Authenticate;
+			var response = new Mock<Response>();
+
+			proxy.Setup(p => p.Connect(It.IsAny<Guid>())).Returns(connectionResponse);
+			proxy.Setup(p => p.Send(It.IsAny<Message>())).Returns(response.Object);
+			proxy.As<ICommunicationObject>().Setup(o => o.State).Returns(CommunicationState.Opened);
+			proxyObjectFactory.Setup(f => f.CreateObject(It.IsAny<string>())).Returns(proxy.Object);
+
+			var token = Guid.NewGuid();
+			var connected = sut.Connect(token);
+			var received = sut.Send(purport);
+
+			proxy.Verify(p => p.Send(It.Is<SimpleMessage>(m => m.Purport == purport)));
+		}
+
+		[TestMethod]
+		public void MustTestAcknowledgeResponsesCorrectly()
+		{
+			var nullResponse = sut.IsAcknowledged(null);
+			var notAcknowledge = sut.IsAcknowledged(new SimpleResponse(SimpleResponsePurport.Unauthorized));
+			var acknowledge = sut.IsAcknowledged(new SimpleResponse(SimpleResponsePurport.Acknowledged));
+
+			Assert.IsFalse(nullResponse);
+			Assert.IsFalse(notAcknowledge);
+			Assert.IsTrue(acknowledge);
+		}
+
+		[TestMethod]
+		public void MustToStringSafely()
+		{
+			var message = new Mock<Message>();
+			var response = new Mock<Response>();
+
+			message.Setup(m => m.ToString()).Returns(nameof(Message));
+			response.Setup(r => r.ToString()).Returns(nameof(Response));
+
+			var nullStringMessage = sut.ToString(null as Message);
+			var nullStringResponse = sut.ToString(null as Response);
+			var messageString = sut.ToString(message.Object);
+			var responseString = sut.ToString(response.Object);
+
+			Assert.IsNotNull(nullStringMessage);
+			Assert.IsNotNull(nullStringResponse);
+			Assert.IsNotNull(messageString);
+			Assert.IsNotNull(responseString);
+			Assert.AreEqual(message.Object.ToString(), messageString);
+			Assert.AreEqual(response.Object.ToString(), responseString);
+		}
+
+		[TestMethod]
+		public void TestConnectionMustPingHost()
+		{
+			var proxy = new Mock<ICommunication>();
+			var connectionResponse = new ConnectionResponse
+			{
+				CommunicationToken = Guid.NewGuid(),
+				ConnectionEstablished = true
+			};
+
+			proxy.Setup(p => p.Connect(It.IsAny<Guid>())).Returns(connectionResponse);
+			proxy.Setup(p => p.Send(It.Is<SimpleMessage>(m => m.Purport == SimpleMessagePurport.Ping))).Returns(new SimpleResponse(SimpleResponsePurport.Acknowledged));
+			proxy.As<ICommunicationObject>().Setup(o => o.State).Returns(CommunicationState.Opened);
+			proxyObjectFactory.Setup(f => f.CreateObject(It.IsAny<string>())).Returns(proxy.Object);
+
+			var token = Guid.NewGuid();
+			var connected = sut.Connect(token);
+
+			sut.TestConnection();
+
+			proxy.Verify();
+		}
+
+		[TestMethod]
+		public void TestConnectionMustInvokeConnectionLostEvent()
+		{
+			var lost = false;
+			var proxy = new Mock<ICommunication>();
+			var connectionResponse = new ConnectionResponse
+			{
+				CommunicationToken = Guid.NewGuid(),
+				ConnectionEstablished = true
+			};
+
+			sut.ConnectionLost += () => lost = true;
+
+			proxy.Setup(p => p.Connect(It.IsAny<Guid>())).Returns(connectionResponse);
+			proxy.Setup(p => p.Send(It.Is<SimpleMessage>(m => m.Purport == SimpleMessagePurport.Ping))).Returns(new SimpleResponse(SimpleResponsePurport.UnknownMessage));
+			proxy.As<ICommunicationObject>().Setup(o => o.State).Returns(CommunicationState.Opened);
+			proxyObjectFactory.Setup(f => f.CreateObject(It.IsAny<string>())).Returns(proxy.Object);
+
+			var token = Guid.NewGuid();
+			var connected = sut.Connect(token);
+
+			sut.TestConnection();
+
+			Assert.IsTrue(lost);
+		}
+
+		[TestMethod]
+		public void TestConnectionMustNotFail()
+		{
+			var lost = false;
+			var proxy = new Mock<ICommunication>();
+			var connectionResponse = new ConnectionResponse
+			{
+				CommunicationToken = Guid.NewGuid(),
+				ConnectionEstablished = true
+			};
+
+			sut.ConnectionLost += () => lost = true;
+
+			proxy.Setup(p => p.Connect(It.IsAny<Guid>())).Returns(connectionResponse);
+			proxy.Setup(p => p.Send(It.IsAny<Message>())).Throws<Exception>();
+			proxy.As<ICommunicationObject>().Setup(o => o.State).Returns(CommunicationState.Opened);
+			proxyObjectFactory.Setup(f => f.CreateObject(It.IsAny<string>())).Returns(proxy.Object);
+
+			var token = Guid.NewGuid();
+			var connected = sut.Connect(token);
+
+			sut.TestConnection();
+
+			Assert.IsTrue(lost);
+		}
 	}
 }

SafeExamBrowser.Core/Communication/BaseProxy.cs

@@ -122,6 +122,35 @@ namespace SafeExamBrowser.Core.Communication
 			return response is SimpleResponse simpleResponse && simpleResponse.Purport == SimpleResponsePurport.Acknowledged;
 		}
 
+		/// <summary>
+		/// Tests whether the connection to the host is alive by sending a ping message. If the transmission of the message fails or it is
+		/// not acknowledged, the <see cref="ConnectionLost"/> event is fired and the auto-ping timer stopped (if it was initialized).
+		/// </summary>
+		protected void TestConnection()
+		{
+			try
+			{
+				var response = Send(SimpleMessagePurport.Ping);
+
+				if (IsAcknowledged(response))
+				{
+					Logger.Info("Pinged host, connection is alive.");
+				}
+				else
+				{
+					Logger.Error($"Host did not acknowledge ping message! Received: {ToString(response)}.");
+					timer?.Stop();
+					ConnectionLost?.Invoke();
+				}
+			}
+			catch (Exception e)
+			{
+				Logger.Error("Failed to ping host!", e);
+				timer?.Stop();
+				ConnectionLost?.Invoke();
+			}
+		}
+
 		/// <summary>
 		/// Retrieves the string representation of the given <see cref="Message"/>, or indicates that a message is <c>null</c>.
 		/// </summary>
@@ -205,27 +234,7 @@ namespace SafeExamBrowser.Core.Communication
 			{
 				if (timer.Enabled)
 				{
-					try
+					TestConnection();
-					{
-						var response = Send(SimpleMessagePurport.Ping);
-
-						if (IsAcknowledged(response))
-						{
-							Logger.Info("Pinged host, connection is alive.");
-						}
-						else
-						{
-							Logger.Error($"Host did not acknowledge ping message! Received: {ToString(response)}.");
-							timer.Stop();
-							ConnectionLost?.Invoke();
-						}
-					}
-					catch (Exception e)
-					{
-						Logger.Error("Failed to ping host!", e);
-						timer.Stop();
-						ConnectionLost?.Invoke();
-					}
 				}
 			}
 		}