SEBWIN-405: Implemented scaffolding for detection of session identifier.

SafeExamBrowser.Browser.Contracts/Events/SessionIdentifierDetectedEventHandler.cs

@@ -0,0 +1,15 @@
+/*
+ * Copyright (c) 2020 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.Browser.Contracts.Events
+{
+	/// <summary>
+	/// Event handler used to indicate that the browser has detected a session identifier of a LMS.
+	/// </summary>
+	public delegate void SessionIdentifierDetectedEventHandler(string identifier);
+}

SafeExamBrowser.Browser.Contracts/IBrowserApplication.cs

@@ -21,6 +21,11 @@ namespace SafeExamBrowser.Browser.Contracts
 		/// </summary>
 		event DownloadRequestedEventHandler ConfigurationDownloadRequested;
 
+		/// <summary>
+		/// Event fired when the browser application detects a session identifier of an LMS.
+		/// </summary>
+		event SessionIdentifierDetectedEventHandler SessionIdentifierDetected;
+
 		/// <summary>
 		/// Event fired when the browser application detects a request to terminate SEB.
 		/// </summary>

SafeExamBrowser.Browser.Contracts/SafeExamBrowser.Browser.Contracts.csproj

@@ -57,6 +57,7 @@
     <Compile Include="Events\DownloadEventArgs.cs" />
     <Compile Include="Events\DownloadFinishedCallback.cs" />
     <Compile Include="Events\DownloadRequestedEventHandler.cs" />
+    <Compile Include="Events\SessionIdentifierDetectedEventHandler.cs" />
     <Compile Include="Events\TerminationRequestedEventHandler.cs" />
     <Compile Include="Filters\IRequestFilter.cs" />
     <Compile Include="Filters\IRule.cs" />

SafeExamBrowser.Browser/BrowserApplication.cs

@@ -10,6 +10,7 @@ using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
+using System.Timers;
 using CefSharp;
 using CefSharp.WinForms;
 using SafeExamBrowser.Applications.Contracts;
@@ -39,8 +40,10 @@ namespace SafeExamBrowser.Browser
 		private IFileSystemDialog fileSystemDialog;
 		private IMessageBox messageBox;
 		private IModuleLogger logger;
+		private List<string> sessionCookies;
 		private BrowserSettings settings;
 		private IText text;
+		private Timer timer;
 		private IUserInterfaceFactory uiFactory;
 
 		public bool AutoStart { get; private set; }
@@ -50,8 +53,9 @@ namespace SafeExamBrowser.Browser
 		public string Tooltip { get; private set; }
 
 		public event DownloadRequestedEventHandler ConfigurationDownloadRequested;
-		public event WindowsChangedEventHandler WindowsChanged;
+		public event SessionIdentifierDetectedEventHandler SessionIdentifierDetected;
 		public event TerminationRequestedEventHandler TerminationRequested;
+		public event WindowsChangedEventHandler WindowsChanged;
 
 		public BrowserApplication(
 			AppConfig appConfig,
@@ -67,8 +71,10 @@ namespace SafeExamBrowser.Browser
 			this.instances = new List<BrowserApplicationInstance>();
 			this.logger = logger;
 			this.messageBox = messageBox;
+			this.sessionCookies = new List<string>();
 			this.settings = settings;
 			this.text = text;
+			this.timer = new Timer();
 			this.uiFactory = uiFactory;
 		}
 
@@ -104,12 +110,15 @@ namespace SafeExamBrowser.Browser
 		public void Start()
 		{
 			CreateNewInstance();
+			StartMonitoringCookies();
 		}
 
 		public void Terminate()
 		{
 			logger.Info("Initiating termination...");
 
+			StopMonitoringCookies();
+
 			foreach (var instance in instances)
 			{
 				instance.Terminated -= Instance_Terminated;
@@ -294,6 +303,19 @@ namespace SafeExamBrowser.Browser
 			return userAgent;
 		}
 
+		private void StartMonitoringCookies()
+		{
+			timer.AutoReset = false;
+			timer.Interval = 1000;
+			timer.Elapsed += Timer_Elapsed;
+			timer.Start();
+		}
+
+		private void StopMonitoringCookies()
+		{
+			timer.Stop();
+		}
+
 		private string ToScheme(ProxyProtocol protocol)
 		{
 			switch (protocol)
@@ -322,5 +344,35 @@ namespace SafeExamBrowser.Browser
 			instances.Remove(instances.First(i => i.Id == id));
 			WindowsChanged?.Invoke();
 		}
+
+		private void Timer_Elapsed(object sender, ElapsedEventArgs args)
+		{
+			try
+			{
+				var manager = Cef.GetGlobalCookieManager();
+				var task = manager.VisitAllCookiesAsync();
+				var cookies = task.GetAwaiter().GetResult();
+				var edxLogin = cookies.FirstOrDefault(c => c.Name == "edxloggedin");
+
+				// TODO: MoodleSession
+
+				if (edxLogin != default(Cookie))
+				{
+					var edxSession = cookies.FirstOrDefault(c => c.Domain == edxLogin.Domain && c.Name == "sessionid");
+
+					if (edxSession != default(Cookie) && !sessionCookies.Contains(edxSession.Domain))
+					{
+						sessionCookies.Add(edxSession.Domain);
+						SessionIdentifierDetected?.Invoke(edxSession.Value);
+					}
+				}
+			}
+			catch (Exception e)
+			{
+				logger.Error("Failed to read cookies!", e);
+			}
+
+			timer.Start();
+		}
 	}
 }

SafeExamBrowser.Client/ClientContext.cs

@@ -49,7 +49,7 @@ namespace SafeExamBrowser.Client
 		internal IClientHost ClientHost { get; set; }
 
 		/// <summary>
-		/// The server proxy, if the current session mode is <see cref="SessionMode.Server"/>.
+		/// The server proxy (if the current session mode is <see cref="SessionMode.Server"/>).
 		/// </summary>
 		internal IServerProxy Server { get; set; }
 

SafeExamBrowser.Client/ClientController.cs

@@ -10,6 +10,7 @@ using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
+using System.Threading;
 using SafeExamBrowser.Applications.Contracts;
 using SafeExamBrowser.Browser.Contracts;
 using SafeExamBrowser.Browser.Contracts.Events;
@@ -183,6 +184,7 @@ namespace SafeExamBrowser.Client
 			applicationMonitor.ExplorerStarted += ApplicationMonitor_ExplorerStarted;
 			applicationMonitor.TerminationFailed += ApplicationMonitor_TerminationFailed;
 			Browser.ConfigurationDownloadRequested += Browser_ConfigurationDownloadRequested;
+			Browser.SessionIdentifierDetected += Browser_SessionIdentifierDetected;
 			Browser.TerminationRequested += Browser_TerminationRequested;
 			ClientHost.MessageBoxRequested += ClientHost_MessageBoxRequested;
 			ClientHost.PasswordRequested += ClientHost_PasswordRequested;
@@ -218,6 +220,8 @@ namespace SafeExamBrowser.Client
 			if (Browser != null)
 			{
 				Browser.ConfigurationDownloadRequested -= Browser_ConfigurationDownloadRequested;
+				Browser.SessionIdentifierDetected -= Browser_SessionIdentifierDetected;
+				Browser.TerminationRequested -= Browser_TerminationRequested;
 			}
 
 			if (ClientHost != null)
@@ -341,6 +345,24 @@ namespace SafeExamBrowser.Client
 			}
 		}
 
+		private void Browser_SessionIdentifierDetected(string identifier)
+		{
+			if (Settings.SessionMode == SessionMode.Server)
+			{
+				var response = Server.SendSessionIdentifier(identifier);
+
+				while (!response.Success)
+				{
+					logger.Error($"Failed to communicate session identifier with server! {response.Message}");
+					// TODO: Check that is running in separat thread (not UI thread!!) or use different mechanism to wait!
+					Thread.Sleep(Settings.Server.RequestAttemptInterval);
+					response = Server.SendSessionIdentifier(identifier);
+				}
+
+				Server.StartConnectivity();
+			}
+		}
+
 		private void Browser_TerminationRequested()
 		{
 			logger.Info("Attempting to shutdown as requested by the browser...");

SafeExamBrowser.Client/CompositionRoot.cs

@@ -244,6 +244,8 @@ namespace SafeExamBrowser.Client
 			var server = new ServerProxy(context.AppConfig, logger);
 			var operation = new ServerOperation(actionCenter, context, logger, server, taskbar);
 
+			context.Server = server;
+
 			return operation;
 		}
 

SafeExamBrowser.Client/Operations/ServerOperation.cs

@@ -48,7 +48,12 @@ namespace SafeExamBrowser.Client.Operations
 				logger.Info("Initializing server...");
 				StatusChanged?.Invoke(TextKey.OperationStatus_InitializeServer);
 
-				server.Initialize(Context.AppConfig.ServerApi, Context.AppConfig.ServerConnectionToken, Context.AppConfig.ServerOauth2Token, Context.Settings.Server);
+				server.Initialize(
+					Context.AppConfig.ServerApi,
+					Context.AppConfig.ServerConnectionToken,
+					Context.AppConfig.ServerExamId,
+					Context.AppConfig.ServerOauth2Token,
+					Context.Settings.Server);
 
 				// TODO: Add action center and taskbar notifications
 			}
@@ -66,6 +71,7 @@ namespace SafeExamBrowser.Client.Operations
 				StatusChanged?.Invoke(TextKey.OperationStatus_FinalizeServer);
 
 				// TODO: Stop sending pings and logs (or in controller?)
+				server.StopConnectivity();
 				// TODO: Stop action center and taskbar notifications
 			}
 

SafeExamBrowser.Configuration.Contracts/AppConfig.cs

@@ -161,6 +161,11 @@ namespace SafeExamBrowser.Configuration.Contracts
 		/// </summary>
 		public string ServerConnectionToken { get; set; }
 
+		/// <summary>
+		/// The identifier of the selected server exam.
+		/// </summary>
+		public string ServerExamId { get; set; }
+
 		/// <summary>
 		/// The OAuth2 token for a server.
 		/// </summary>

SafeExamBrowser.Runtime/Operations/ServerOperation.cs

@@ -77,11 +77,18 @@ namespace SafeExamBrowser.Runtime.Operations
 
 								if (status == LoadStatus.Success)
 								{
+									var serverSettings = Context.Next.Settings.Server;
+
 									Context.Next.AppConfig.ServerApi = info.Api;
 									Context.Next.AppConfig.ServerConnectionToken = info.ConnectionToken;
+									Context.Next.AppConfig.ServerExamId = exam.Id;
 									Context.Next.AppConfig.ServerOauth2Token = info.Oauth2Token;
+
 									Context.Next.Settings = settings;
 									Context.Next.Settings.Browser.StartUrl = exam.Url;
+									Context.Next.Settings.Server = serverSettings;
+									Context.Next.Settings.SessionMode = SessionMode.Server;
+
 									result = OperationResult.Success;
 								}
 								else
@@ -105,6 +112,7 @@ namespace SafeExamBrowser.Runtime.Operations
 
 				if (fallback)
 				{
+					Context.Next.Settings.SessionMode = SessionMode.Normal;
 					result = OperationResult.Success;
 				}
 			}

SafeExamBrowser.Server.Contracts/IServerProxy.cs

@@ -51,11 +51,21 @@ namespace SafeExamBrowser.Server.Contracts
 		/// <summary>
 		/// Initializes the configuration and server settings to be used for communication.
 		/// </summary>
-		void Initialize(string api, string connectionToken, string oauth2Token, ServerSettings settings);
+		void Initialize(string api, string connectionToken, string examId, string oauth2Token, ServerSettings settings);
 
 		/// <summary>
 		/// TODO
 		/// </summary>
-		ServerResponse SendSessionInfo(string sessionId);
+		ServerResponse SendSessionIdentifier(string identifier);
+
+		/// <summary>
+		/// TODO
+		/// </summary>
+		void StartConnectivity();
+
+		/// <summary>
+		/// TODO
+		/// </summary>
+		void StopConnectivity();
 	}
 }

SafeExamBrowser.Server/ServerProxy.cs

@@ -29,6 +29,7 @@ namespace SafeExamBrowser.Server
 	{
 		private ApiVersion1 api;
 		private string connectionToken;
+		private string examId;
 		private HttpClient httpClient;
 		private readonly AppConfig appConfig;
 		private ILogger logger;
@@ -173,20 +174,31 @@ namespace SafeExamBrowser.Server
 			}
 		}
 
-		public void Initialize(string api, string connectionToken, string oauth2Token, ServerSettings settings)
+		public void Initialize(string api, string connectionToken, string examId, string oauth2Token, ServerSettings settings)
 		{
 			this.api = JsonConvert.DeserializeObject<ApiVersion1>(api);
 			this.connectionToken = connectionToken;
+			this.examId = examId;
 			this.oauth2Token = oauth2Token;
 
 			Initialize(settings);
 		}
 
-		public ServerResponse SendSessionInfo(string sessionId)
+		public ServerResponse SendSessionIdentifier(string identifier)
 		{
 			return new ServerResponse(false, "TODO!");
 		}
 
+		public void StartConnectivity()
+		{
+			// TODO: Start sending logs and pings
+		}
+
+		public void StopConnectivity()
+		{
+			// TODO: Stop sending logs and pings
+		}
+
 		private bool TryParseApi(HttpContent content)
 		{
 			var success = false;