Replace NetMQ with custom TCP logic

Agent/Phantom.Agent.Services/AgentServices.cs

@@ -19,6 +19,8 @@ public sealed class AgentServices {
 	
 	public ActorSystem ActorSystem { get; }
 	
+	private ControllerConnection ControllerConnection { get; }
+	
 	private AgentInfo AgentInfo { get; }
 	private AgentFolders AgentFolders { get; }
 	private AgentState AgentState { get; }
@@ -31,6 +33,8 @@ public sealed class AgentServices {
 	public AgentServices(AgentInfo agentInfo, AgentFolders agentFolders, AgentServiceConfiguration serviceConfiguration, ControllerConnection controllerConnection) {
 		this.ActorSystem = ActorSystemFactory.Create("Agent");
 		
+		this.ControllerConnection = controllerConnection;
+		
 		this.AgentInfo = agentInfo;
 		this.AgentFolders = agentFolders;
 		this.AgentState = new AgentState();
@@ -49,14 +53,14 @@ public sealed class AgentServices {
 		}
 	}
 	
-	public  async Task<bool> Register(ControllerConnection connection, CancellationToken cancellationToken) {
+	public async Task<bool> Register(CancellationToken cancellationToken) {
 		Logger.Information("Registering with the controller...");
 		
 		// TODO NEED TO SEND WHEN SERVER RESTARTS!!!
 		
 		ImmutableArray<ConfigureInstanceMessage> configureInstanceMessages;
 		try {
-			configureInstanceMessages = await connection.Send<RegisterAgentMessage, ImmutableArray<ConfigureInstanceMessage>>(new RegisterAgentMessage(AgentInfo), TimeSpan.FromMinutes(1), cancellationToken);
+			configureInstanceMessages = await ControllerConnection.Send<RegisterAgentMessage, ImmutableArray<ConfigureInstanceMessage>>(new RegisterAgentMessage(AgentInfo), TimeSpan.FromMinutes(1), cancellationToken);
 		} catch (Exception e) {
 			Logger.Fatal(e, "Registration failed.");
 			return false;
@@ -78,7 +82,7 @@ public sealed class AgentServices {
 			}
 		}
 		
-		await connection.Send(new AdvertiseJavaRuntimesMessage(JavaRuntimeRepository.All), cancellationToken);
+		await ControllerConnection.Send(new AdvertiseJavaRuntimesMessage(JavaRuntimeRepository.All), cancellationToken);
 		InstanceTicketManager.RefreshAgentStatus();
 		
 		return true;

Agent/Phantom.Agent/Program.cs

@@ -62,14 +62,12 @@ try {
 		return 1;
 	}
 	
-	var controllerConnection = new ControllerConnection(rpcClient.SendChannel);
-	
 	Task? rpcClientListener = null;
 	try {
 		PhantomLogger.Root.InformationHeading("Launching Phantom Panel agent...");
 		
 		var agentInfo = new AgentInfo(agentGuid.Value, agentName, ProtocolVersion, fullVersion, maxInstances, maxMemory, allowedServerPorts, allowedRconPorts);
-		var agentServices = new AgentServices(agentInfo, folders, new AgentServiceConfiguration(maxConcurrentBackupCompressionTasks), controllerConnection);
+		var agentServices = new AgentServices(agentInfo, folders, new AgentServiceConfiguration(maxConcurrentBackupCompressionTasks), new ControllerConnection(rpcClient.SendChannel));
 		await agentServices.Initialize();
 		
 		var rpcMessageHandlerInit = new ControllerMessageHandlerActor.Init(agentServices);
@@ -77,18 +75,21 @@ try {
 		
 		rpcClientListener = rpcClient.Listen(new IMessageReceiver<IMessageToAgent>.Actor(rpcMessageHandlerActor));
 		
-		if (await agentServices.Register(controllerConnection, shutdownCancellationToken)) {
+		if (await agentServices.Register(shutdownCancellationToken)) {
 			PhantomLogger.Root.Information("Phantom Panel agent is ready.");
 			await shutdownCancellationToken.WaitHandle.WaitOneAsync();
 		}
 		
 		await agentServices.Shutdown();
 	} finally {
+		PhantomLogger.Root.Information("Unregistering agent...");
 		try {
-			await controllerConnection.Send(new UnregisterAgentMessage(), CancellationToken.None);
-			// TODO wait for acknowledgment
+			using var unregisterCancellationTokenSource = new CancellationTokenSource(TimeSpan.FromSeconds(10));
+			await rpcClient.SendChannel.SendMessage(new UnregisterAgentMessage(), unregisterCancellationTokenSource.Token);
+		} catch (OperationCanceledException) {
+			PhantomLogger.Root.Warning("Could not unregister agent after shutdown.");
 		} catch (Exception e) {
-			PhantomLogger.Root.Warning(e, "Could not unregister agent after shutdown.");
+			PhantomLogger.Root.Warning(e, "Could not unregister agent during shutdown.");
 		} finally {
 			await rpcClient.Shutdown();
 			

Controller/Phantom.Controller.Services/Agents/AgentConnection.cs

@@ -14,7 +14,7 @@ sealed class AgentConnection(Guid agentGuid, string agentName) {
 	
 	public void UpdateConnection(RpcServerToClientConnection<IMessageToController, IMessageToAgent> newConnection, string newAgentName) {
 		lock (this) {
-			connection?.CloseSession();
+			connection?.ClientClosedSession();
 			connection = newConnection;
 			agentName = newAgentName;
 		}
@@ -23,7 +23,7 @@ sealed class AgentConnection(Guid agentGuid, string agentName) {
 	public bool CloseIfSame(RpcServerToClientConnection<IMessageToController, IMessageToAgent> expected) {
 		lock (this) {
 			if (connection != null && ReferenceEquals(connection, expected)) {
-				connection.CloseSession();
+				connection.ClientClosedSession();
 				connection = null;
 				return true;
 			}

Controller/Phantom.Controller.Services/Rpc/AgentMessageHandlerActor.cs

@@ -1,4 +1,5 @@
 using System.Collections.Immutable;
+using Akka.Actor;
 using Phantom.Common.Messages.Agent;
 using Phantom.Common.Messages.Agent.ToAgent;
 using Phantom.Common.Messages.Agent.ToController;
@@ -31,7 +32,7 @@ sealed class AgentMessageHandlerActor : ReceiveActor<IMessageToController> {
 		this.eventLogManager = init.EventLogManager;
 		
 		ReceiveAsyncAndReply<RegisterAgentMessage, ImmutableArray<ConfigureInstanceMessage>>(HandleRegisterAgent);
-		Receive<UnregisterAgentMessage>(HandleUnregisterAgent);
+		ReceiveAsync<UnregisterAgentMessage>(HandleUnregisterAgent);
 		Receive<AdvertiseJavaRuntimesMessage>(HandleAdvertiseJavaRuntimes);
 		Receive<ReportAgentStatusMessage>(HandleReportAgentStatus);
 		Receive<ReportInstanceStatusMessage>(HandleReportInstanceStatus);
@@ -49,11 +50,13 @@ sealed class AgentMessageHandlerActor : ReceiveActor<IMessageToController> {
 		return agentManager.RegisterAgent(message.AgentInfo, connection);
 	}
 	
-	private void HandleUnregisterAgent(UnregisterAgentMessage message) {
+	private Task HandleUnregisterAgent(UnregisterAgentMessage message) {
 		Guid agentGuid = RequireAgentGuid();
 		agentManager.TellAgent(agentGuid, new AgentActor.UnregisterCommand(connection));
 		agentManager.OnSessionClosed(connection.SessionId, agentGuid);
-		connection.CloseSession();
+		
+		Self.Tell(PoisonPill.Instance);
+		return connection.ClientClosedSession();
 	}
 	
 	private void HandleAdvertiseJavaRuntimes(AdvertiseJavaRuntimesMessage message) {

Controller/Phantom.Controller.Services/Rpc/WebClientRegistrar.cs

@@ -27,7 +27,7 @@ sealed class WebClientRegistrar(
 ) : IRpcServerClientRegistrar<IMessageToController, IMessageToWeb> {
 	public IMessageReceiver<IMessageToController> Register(RpcServerToClientConnection<IMessageToController, IMessageToWeb> connection) {
 		var name = "WebClient-" + connection.SessionId;
-		var init = new WebMessageHandlerActor.Init(connection, this, controllerState, instanceLogManager, userManager, roleManager, userRoleManager, userLoginManager, auditLogManager, agentManager, minecraftVersions, eventLogManager);
+		var init = new WebMessageHandlerActor.Init(connection, controllerState, instanceLogManager, userManager, roleManager, userRoleManager, userLoginManager, auditLogManager, agentManager, minecraftVersions, eventLogManager);
 		return new IMessageReceiver<IMessageToController>.Actor(actorSystem.ActorOf(WebMessageHandlerActor.Factory(init), name));
 	}
 }

Controller/Phantom.Controller.Services/Rpc/WebMessageHandlerActor.cs

@@ -1,4 +1,5 @@
 using System.Collections.Immutable;
+using Akka.Actor;
 using Phantom.Common.Data;
 using Phantom.Common.Data.Java;
 using Phantom.Common.Data.Minecraft;
@@ -23,7 +24,6 @@ namespace Phantom.Controller.Services.Rpc;
 sealed class WebMessageHandlerActor : ReceiveActor<IMessageToController> {
 	public readonly record struct Init(
 		RpcServerToClientConnection<IMessageToController, IMessageToWeb> Connection,
-		WebClientRegistrar WebClientRegistrar,
 		ControllerState ControllerState,
 		InstanceLogManager InstanceLogManager,
 		UserManager UserManager,
@@ -88,7 +88,8 @@ sealed class WebMessageHandlerActor : ReceiveActor<IMessageToController> {
 	}
 	
 	private Task HandleUnregisterWeb(UnregisterWebMessage message) {
-		return connection.CloseSession();
+		Self.Tell(PoisonPill.Instance);
+		return connection.ClientClosedSession();
 	}
 	
 	private Task<Optional<LogInSuccess>> HandleLogIn(LogInMessage message) {

Utils/Phantom.Utils.Rpc/Frame/IFrame.cs

@@ -24,7 +24,7 @@ interface IFrame {
 			switch (oneByteBuffer[0]) {
 				case TypePingId:
 					var pingTime = await PingFrame.Read(stream, cancellationToken);
-					await reader.OnPing(pingTime, cancellationToken);
+					await reader.OnPingFrame(pingTime, cancellationToken);
 					break;
 				
 				case TypePongId:
@@ -48,7 +48,7 @@ interface IFrame {
 					break;
 				
 				default:
-					reader.OnUnknownFrameStart(oneByteBuffer[0]);
+					reader.OnUnknownFrameId(oneByteBuffer[0]);
 					break;
 			}
 		}

Utils/Phantom.Utils.Rpc/Frame/IFrameReader.cs

@@ -3,10 +3,10 @@
 namespace Phantom.Utils.Rpc.Frame;
 
 interface IFrameReader {
-	ValueTask OnPing(DateTimeOffset pingTime, CancellationToken cancellationToken);
+	ValueTask OnPingFrame(DateTimeOffset pingTime, CancellationToken cancellationToken);
 	void OnPongFrame(PongFrame frame);
 	Task OnMessageFrame(MessageFrame frame, CancellationToken cancellationToken);
 	void OnReplyFrame(ReplyFrame frame);
 	void OnErrorFrame(ErrorFrame frame);
-	void OnUnknownFrameStart(byte id);
+	void OnUnknownFrameId(byte frameId);
 }

Utils/Phantom.Utils.Rpc/Message/MessageReceiveTracker.cs

@@ -0,0 +1,13 @@
+using Phantom.Utils.Collections;
+
+namespace Phantom.Utils.Rpc.Message;
+
+sealed class MessageReceiveTracker {
+	private readonly RangeSet<uint> receivedMessageIds = new ();
+	
+	public bool ReceiveMessage(uint messageId) {
+		lock (receivedMessageIds) {
+			return receivedMessageIds.Add(messageId);
+		}
+	}
+}

Utils/Phantom.Utils.Rpc/Runtime/Client/RpcClient.cs

@@ -13,15 +13,17 @@ public sealed class RpcClient<TClientToServerMessage, TServerToClientMessage> :
 	
 	private readonly string loggerName;
 	private readonly ILogger logger;
-	private readonly MessageRegistry<TServerToClientMessage> serverToClientMessageRegistry;
+	private readonly MessageRegistry<TServerToClientMessage> messageRegistry;
+	private readonly MessageReceiveTracker messageReceiveTracker = new ();
 	private readonly RpcClientToServerConnection connection;
+	private readonly CancellationTokenSource shutdownCancellationTokenSource = new ();
 	
 	public RpcSendChannel<TClientToServerMessage> SendChannel { get; }
 	
 	private RpcClient(string loggerName, RpcClientConnectionParameters connectionParameters, IMessageDefinitions<TClientToServerMessage, TServerToClientMessage> messageDefinitions, RpcClientToServerConnector connector, RpcClientToServerConnector.Connection connection) {
 		this.loggerName = loggerName;
 		this.logger = PhantomLogger.Create<RpcClient<TClientToServerMessage, TServerToClientMessage>>(loggerName);
-		this.serverToClientMessageRegistry = messageDefinitions.ToClient;
+		this.messageRegistry = messageDefinitions.ToClient;
 		
 		this.connection = new RpcClientToServerConnection(loggerName, connector, connection);
 		this.SendChannel = new RpcSendChannel<TClientToServerMessage>(loggerName, connectionParameters.Common, this.connection, messageDefinitions.ToServer);
@@ -29,9 +31,9 @@ public sealed class RpcClient<TClientToServerMessage, TServerToClientMessage> :
 	
 	public async Task Listen(IMessageReceiver<TServerToClientMessage> receiver) {
 		var messageHandler = new RpcMessageHandler<TServerToClientMessage>(receiver, SendChannel);
-		var frameReader = new RpcFrameReader<TClientToServerMessage, TServerToClientMessage>(loggerName, serverToClientMessageRegistry, messageHandler, SendChannel);
+		var frameReader = new RpcFrameReader<TClientToServerMessage, TServerToClientMessage>(loggerName, messageRegistry, messageReceiveTracker, messageHandler, SendChannel);
 		try {
-			await connection.ReadConnection(frameReader, CancellationToken.None);
+			await connection.ReadConnection(frameReader, shutdownCancellationTokenSource.Token);
 		} catch (OperationCanceledException) {
 			// Ignore.
 		}
@@ -47,11 +49,13 @@ public sealed class RpcClient<TClientToServerMessage, TServerToClientMessage> :
 		}
 		
 		try {
-			connection.Close();
+			connection.StopReconnecting();
 		} catch (Exception e) {
 			logger.Error(e, "Caught exception while closing connection.");
 		}
 		
+		await shutdownCancellationTokenSource.CancelAsync();
+		
 		logger.Information("Client shut down.");
 	}
 	

Utils/Phantom.Utils.Rpc/Runtime/Client/RpcClientToServerConnection.cs

@@ -1,4 +1,5 @@
-using Phantom.Utils.Logging;
+using System.Net.Sockets;
+using Phantom.Utils.Logging;
 using Phantom.Utils.Rpc.Frame;
 using Serilog;
 
@@ -12,7 +13,7 @@ sealed class RpcClientToServerConnection(string loggerName, RpcClientToServerCon
 	
 	private readonly CancellationTokenSource newConnectionCancellationTokenSource = new ();
 	
-	public async Task<Stream> GetStream() {
+	public async Task<Stream> GetStream(CancellationToken cancellationToken) {
 		return (await GetConnection()).Stream;
 	}
 	
@@ -54,20 +55,22 @@ sealed class RpcClientToServerConnection(string loggerName, RpcClientToServerCon
 					throw;
 				} catch (EndOfStreamException) {
 					logger.Warning("Socket was closed.");
+				} catch (SocketException e) {
+					logger.Error("Socket reading was interrupted. Socket error {ErrorCode} ({ErrorCodeName}), reason: {ErrorMessage}", e.ErrorCode, e.SocketErrorCode, e.Message);
 				} catch (Exception e) {
-					logger.Error(e, "Closing socket due to an exception while reading it.");
+					logger.Error(e, "Socket reading was interrupted.");
+				}
 				
 				try {
 					await connection.Shutdown();
-					} catch (Exception e2) {
-						logger.Error(e2, "Caught exception closing the socket.");
-					}
+				} catch (Exception e) {
+					logger.Error(e, "Caught exception closing the socket.");
 				}
 			}
 		} finally {
 			if (connection != null) {
 				try {
-					await connection.Disconnect(); // TODO what happens if already disconnected?
+					await connection.Disconnect();
 				} finally {
 					connection.Dispose();
 				}
@@ -75,7 +78,7 @@ sealed class RpcClientToServerConnection(string loggerName, RpcClientToServerCon
 		}
 	}
 	
-	public void Close() {
+	public void StopReconnecting() {
 		newConnectionCancellationTokenSource.Cancel();
 	}
 	

Utils/Phantom.Utils.Rpc/Runtime/Client/RpcClientToServerConnector.cs

@@ -53,7 +53,8 @@ internal sealed class RpcClientToServerConnector {
 				return newConnection;
 			}
 			
-			logger.Warning("Failed to connect to server, trying again in {}.", nextAttemptDelay.TotalSeconds.ToString("F1"));
+			cancellationToken.ThrowIfCancellationRequested();
+			logger.Information("Trying to reconnect in {Seconds}s.", nextAttemptDelay.TotalSeconds.ToString("F1"));
 			
 			await Task.Delay(nextAttemptDelay, cancellationToken);
 			nextAttemptDelay = Comparables.Min(nextAttemptDelay.Multiply(1.5), MaximumRetryDelay);
@@ -66,9 +67,12 @@ internal sealed class RpcClientToServerConnector {
 		Socket clientSocket = new Socket(SocketType.Stream, ProtocolType.Tcp);
 		try {
 			await clientSocket.ConnectAsync(parameters.Host, parameters.Port, cancellationToken);
+		} catch (SocketException e) {
+			logger.Error("Could not connect. Socket error {ErrorCode} ({ErrorCodeName}), reason: {ErrorMessage}", e.ErrorCode, e.SocketErrorCode, e.Message);
+			return null;
 		} catch (Exception e) {
 			logger.Error(e, "Could not connect.");
-			throw;
+			return null;
 		}
 		
 		SslStream? stream;

Utils/Phantom.Utils.Rpc/Runtime/IRpcConnectionProvider.cs

@@ -1,5 +1,5 @@
 namespace Phantom.Utils.Rpc.Runtime;
 
 interface IRpcConnectionProvider {
-	Task<Stream> GetStream();
+	Task<Stream> GetStream(CancellationToken cancellationToken);
 }

Utils/Phantom.Utils.Rpc/Runtime/RpcError.cs

@@ -3,7 +3,8 @@
 public enum RpcError : byte {
 	InvalidData = 0,
 	UnknownMessageRegistryCode = 1,
-	MessageDeserializationError = 2,
-	MessageHandlingError = 3,
-	MessageTooLarge = 4,
+	MessageTooLarge = 2,
+	MessageDeserializationError = 3,
+	MessageHandlingError = 4,
+	MessageAlreadyHandled = 5,
 }

Utils/Phantom.Utils.Rpc/Runtime/RpcErrorException.cs

@@ -1,13 +1,14 @@
 namespace Phantom.Utils.Rpc.Runtime;
 
-public sealed class RpcErrorException : Exception {
+sealed class RpcErrorException : Exception {
 	internal static RpcErrorException From(RpcError error) {
 		return error switch {
 			RpcError.InvalidData                 => new RpcErrorException("Invalid data", error),
 			RpcError.UnknownMessageRegistryCode  => new RpcErrorException("Unknown message registry code", error),
+			RpcError.MessageTooLarge             => new RpcErrorException("Message is too large", error),
 			RpcError.MessageDeserializationError => new RpcErrorException("Message deserialization error", error),
 			RpcError.MessageHandlingError        => new RpcErrorException("Message handling error", error),
-			RpcError.MessageTooLarge             => new RpcErrorException("Message is too large", error),
+			RpcError.MessageAlreadyHandled       => new RpcErrorException("Message already handled", error),
 			_                                    => new RpcErrorException("Unknown error", error),
 		};
 	}

Utils/Phantom.Utils.Rpc/Runtime/RpcFrameReader.cs

@@ -9,12 +9,13 @@ namespace Phantom.Utils.Rpc.Runtime;
 sealed class RpcFrameReader<TSentMessage, TReceivedMessage>(
 	string loggerName,
 	MessageRegistry<TReceivedMessage> messageRegistry,
+	MessageReceiveTracker messageReceiveTracker,
 	RpcMessageHandler<TReceivedMessage> messageHandler,
 	RpcSendChannel<TSentMessage> sendChannel
 ) : IFrameReader {
 	private readonly ILogger logger = PhantomLogger.Create<RpcFrameReader<TSentMessage, TReceivedMessage>>(loggerName);
 	
-	public ValueTask OnPing(DateTimeOffset pingTime, CancellationToken cancellationToken) {
+	public ValueTask OnPingFrame(DateTimeOffset pingTime, CancellationToken cancellationToken) {
 		messageHandler.OnPing();
 		return sendChannel.SendPong(pingTime, cancellationToken);
 	}
@@ -24,6 +25,11 @@ sealed class RpcFrameReader<TSentMessage, TReceivedMessage>(
 	}
 	
 	public Task OnMessageFrame(MessageFrame frame, CancellationToken cancellationToken) {
+		if (!messageReceiveTracker.ReceiveMessage(frame.MessageId)) {
+			logger.Warning("Received duplicate message {MessageId}.", frame.MessageId);
+			return messageHandler.SendError(frame.MessageId, RpcError.MessageAlreadyHandled, cancellationToken).AsTask();
+		}
+		
 		if (messageRegistry.TryGetType(frame, out var messageType)) {
 			logger.Verbose("Received message {MesageId} of type {MessageType} ({Bytes} B).", frame.MessageId, messageType.Name, frame.SerializedMessage.Length);
 		}
@@ -41,7 +47,7 @@ sealed class RpcFrameReader<TSentMessage, TReceivedMessage>(
 		sendChannel.ReceiveError(frame.ReplyingToMessageId, frame.Error);
 	}
 	
-	public void OnUnknownFrameStart(byte id) {
-		logger.Error("Received unknown frame ID: {FrameId}", id);
+	public void OnUnknownFrameId(byte frameId) {
+		logger.Error("Received unknown frame ID: {FrameId}", frameId);
 	}
 }

Utils/Phantom.Utils.Rpc/Runtime/RpcSendChannel.cs

@@ -19,6 +19,7 @@ public sealed class RpcSendChannel<TMessageBase> : IRpcReplySender, IDisposable
 	private readonly Task sendQueueTask;
 	private readonly Task pingTask;
 	
+	private readonly CancellationTokenSource sendQueueCancellationTokenSource = new ();
 	private readonly CancellationTokenSource pingCancellationTokenSource = new ();
 	
 	private uint nextMessageId;
@@ -88,13 +89,15 @@ public sealed class RpcSendChannel<TMessageBase> : IRpcReplySender, IDisposable
 	}
 	
 	private async Task ProcessSendQueue() {
-		await foreach (IFrame frame in sendQueue.Reader.ReadAllAsync()) {
+		CancellationToken cancellationToken = sendQueueCancellationTokenSource.Token;
+		
+		await foreach (IFrame frame in sendQueue.Reader.ReadAllAsync(cancellationToken)) {
 			while (true) {
 				try {
-					Stream stream = await connectionProvider.GetStream();
-					await stream.WriteAsync(frame.FrameType);
-					await frame.Write(stream);
-					await stream.FlushAsync();
+					Stream stream = await connectionProvider.GetStream(cancellationToken);
+					await stream.WriteAsync(frame.FrameType, cancellationToken);
+					await frame.Write(stream, cancellationToken);
+					await stream.FlushAsync(cancellationToken);
 					break;
 				} catch (OperationCanceledException) {
 					throw;
@@ -115,15 +118,16 @@ public sealed class RpcSendChannel<TMessageBase> : IRpcReplySender, IDisposable
 			pongTask = new TaskCompletionSource<DateTimeOffset>();
 			
 			if (!sendQueue.Writer.TryWrite(PingFrame.Instance)) {
+				cancellationToken.ThrowIfCancellationRequested();
 				logger.Warning("Skipped a ping due to a full queue.");
 				continue;
 			}
 			
-			DateTimeOffset pingTime = await pongTask.Task;
+			DateTimeOffset pingTime = await pongTask.Task.WaitAsync(cancellationToken);
 			DateTimeOffset currentTime = DateTimeOffset.UtcNow;
 			
 			TimeSpan roundTripTime = currentTime - pingTime;
-			logger.Information("Received pong (rtt: {RoundTripTime} ms).", (long) roundTripTime.TotalMilliseconds);
+			logger.Information("Received pong, round trip time: {RoundTripTime} ms", (long) roundTripTime.TotalMilliseconds);
 		}
 	}
 	
@@ -144,7 +148,16 @@ public sealed class RpcSendChannel<TMessageBase> : IRpcReplySender, IDisposable
 		sendQueue.Writer.TryComplete();
 		
 		try {
-			await Task.WhenAll(sendQueueTask, pingTask);
+			await pingTask;
+		} catch (Exception) {
+			// Ignore.
+		}
+		
+		try {
+			await sendQueueTask.WaitAsync(TimeSpan.FromSeconds(15));
+		} catch (TimeoutException) {
+			logger.Warning("Could not finish processing send queue before timeout, forcibly shutting it down.");
+			await sendQueueCancellationTokenSource.CancelAsync();
 		} catch (Exception) {
 			// Ignore.
 		}
@@ -152,6 +165,7 @@ public sealed class RpcSendChannel<TMessageBase> : IRpcReplySender, IDisposable
 	
 	public void Dispose() {
 		sendQueueTask.Dispose();
+		sendQueueCancellationTokenSource.Dispose();
 		pingCancellationTokenSource.Dispose();
 	}
 }

Utils/Phantom.Utils.Rpc/Runtime/Server/RpcServer.cs

@@ -17,7 +17,7 @@ public sealed class RpcServer<TClientToServerMessage, TServerToClientMessage>(
 	IRpcServerClientRegistrar<TClientToServerMessage, TServerToClientMessage> clientRegistrar
 ) {
 	private readonly ILogger logger = PhantomLogger.Create<RpcServer<TClientToServerMessage, TServerToClientMessage>>(loggerName);
-	private readonly RpcServerClientSessions<TServerToClientMessage> clientSessions = new (loggerName, connectionParameters.Common, messageDefinitions.ToClient);
+	private readonly RpcServerClientSessions<TServerToClientMessage> clientSessions = new (connectionParameters.Common, messageDefinitions.ToClient);
 	private readonly List<Client> clients = [];
 	
 	public async Task<bool> Run(CancellationToken shutdownToken) {
@@ -102,7 +102,7 @@ public sealed class RpcServer<TClientToServerMessage, TServerToClientMessage>(
 		
 		private string Address => socket.RemoteEndPoint?.ToString() ?? "<unknown address>";
 		
-		private readonly ILogger logger;
+		private ILogger logger;
 		private readonly string serverLoggerName;
 		
 		private readonly IMessageDefinitions<TClientToServerMessage, TServerToClientMessage> messageDefinitions;
@@ -151,9 +151,10 @@ public sealed class RpcServer<TClientToServerMessage, TServerToClientMessage>(
 				}
 				
 				if (sessionIdResult.HasValue) {
-					logger.Information("Client connected.");
 					await RunConnectedSession(sessionIdResult.Value, stream);
 				}
+			} catch (Exception e) {
+				logger.Error(e, "Caught exception while processing client.");
 			} finally {
 				logger.Information("Disconnecting client...");
 				try {
@@ -220,10 +221,31 @@ public sealed class RpcServer<TClientToServerMessage, TServerToClientMessage>(
 		
 		private async Task RunConnectedSession(Guid sessionId, Stream stream) {
 			var loggerName = PhantomLogger.ConcatNames(serverLoggerName, clientSessions.NextLoggerName(sessionId));
-			var session = clientSessions.OnConnected(sessionId, stream);
+			
+			logger.Information("Client connected with session {SessionId}, new logger name: {LoggerName}", sessionId, loggerName);
+			logger = PhantomLogger.Create<RpcServer<TClientToServerMessage, TServerToClientMessage>, Client>(loggerName);
+			
+			var session = clientSessions.OnConnected(sessionId, loggerName, stream);
 			try {
 				var connection = new RpcServerToClientConnection<TClientToServerMessage, TServerToClientMessage>(loggerName, clientSessions, sessionId, messageDefinitions.ToServer, stream, session);
-				await connection.Listen(clientRegistrar.Register(connection));
+				
+				IMessageReceiver<TClientToServerMessage> messageReceiver;
+				try {
+					messageReceiver = clientRegistrar.Register(connection);
+				} catch (Exception e) {
+					logger.Error(e, "Could not register client.");
+					return;
+				}
+				
+				try {
+					await connection.Listen(messageReceiver);
+				} catch (EndOfStreamException) {
+					logger.Warning("Socket reading was interrupted, connection lost.");
+				} catch (SocketException e) {
+					logger.Error("Socket reading was interrupted. Socket error {ErrorCode} ({ErrorCodeName}), reason: {ErrorMessage}", e.ErrorCode, e.SocketErrorCode, e.Message);
+				} catch (Exception e) {
+					logger.Error(e, "Socket reading was interrupted.");
+				}
 			} finally {
 				clientSessions.OnDisconnected(sessionId);
 			}

Utils/Phantom.Utils.Rpc/Runtime/Server/RpcServerClientSession.cs

@@ -4,11 +4,13 @@ namespace Phantom.Utils.Rpc.Runtime.Server;
 
 sealed class RpcServerClientSession<TServerToClientMessage> : IRpcConnectionProvider {
 	public RpcSendChannel<TServerToClientMessage> SendChannel { get; }
+	public MessageReceiveTracker MessageReceiveTracker { get; }
 	
 	private TaskCompletionSource<Stream> nextStream = new ();
 	
 	public RpcServerClientSession(string loggerName, RpcCommonConnectionParameters connectionParameters, MessageRegistry<TServerToClientMessage> messageRegistry) {
 		this.SendChannel = new RpcSendChannel<TServerToClientMessage>(loggerName, connectionParameters, this, messageRegistry);
+		this.MessageReceiveTracker = new MessageReceiveTracker();
 	}
 	
 	public void OnConnected(Stream stream) {
@@ -29,7 +31,7 @@ sealed class RpcServerClientSession<TServerToClientMessage> : IRpcConnectionProv
 		}
 	}
 	
-	Task<Stream> IRpcConnectionProvider.GetStream() {
+	Task<Stream> IRpcConnectionProvider.GetStream(CancellationToken cancellationToken) {
 		lock (this) {
 			return nextStream.Task;
 		}

Utils/Phantom.Utils.Rpc/Runtime/Server/RpcServerClientSessions.cs

@@ -4,23 +4,34 @@ using Phantom.Utils.Rpc.Message;
 
 namespace Phantom.Utils.Rpc.Runtime.Server;
 
-sealed class RpcServerClientSessions<TServerToClientMessage>(string loggerName, RpcCommonConnectionParameters connectionParameters, MessageRegistry<TServerToClientMessage> messageRegistry) {
+sealed class RpcServerClientSessions<TServerToClientMessage> {
+	private readonly RpcCommonConnectionParameters connectionParameters;
+	private readonly MessageRegistry<TServerToClientMessage> messageRegistry;
+	
 	private readonly ConcurrentDictionary<Guid, RpcServerClientSession<TServerToClientMessage>> sessionsById = new ();
 	private readonly ConcurrentDictionary<Guid, uint> sessionLoggerSequenceIds = new ();
 	
+	private readonly Func<Guid, string, RpcServerClientSession<TServerToClientMessage>> createSessionFunction;
+	
+	public RpcServerClientSessions(RpcCommonConnectionParameters connectionParameters, MessageRegistry<TServerToClientMessage> messageRegistry) {
+		this.connectionParameters = connectionParameters;
+		this.messageRegistry = messageRegistry;
+		this.createSessionFunction = CreateSession;
+	}
+	
 	public string NextLoggerName(Guid sessionId) {
 		string name = PhantomLogger.ShortenGuid(sessionId);
 		return name + "/" + sessionLoggerSequenceIds.AddOrUpdate(sessionId, static _ => 1, static (_, prev) => prev + 1);
 	}
 	
-	public RpcSendChannel<TServerToClientMessage> OnConnected(Guid sessionId, Stream stream) {
-		var session = sessionsById.GetOrAdd(sessionId, CreateSession);
+	public RpcServerClientSession<TServerToClientMessage> OnConnected(Guid sessionId, string loggerName, Stream stream) {
+		var session = sessionsById.GetOrAdd(sessionId, createSessionFunction, loggerName);
 		session.OnConnected(stream);
-		return session.SendChannel;
+		return session;
 	}
 	
-	private RpcServerClientSession<TServerToClientMessage> CreateSession(Guid sessionId) {
-		return new RpcServerClientSession<TServerToClientMessage>(PhantomLogger.ConcatNames(loggerName, sessionId.ToString()), connectionParameters, messageRegistry);
+	private RpcServerClientSession<TServerToClientMessage> CreateSession(Guid sessionId, string loggerName) {
+		return new RpcServerClientSession<TServerToClientMessage>(loggerName, connectionParameters, messageRegistry);
 	}
 	
 	public void OnDisconnected(Guid sessionId) {

Utils/Phantom.Utils.Rpc/Runtime/Server/RpcServerToClientConnection.cs

@@ -1,38 +1,49 @@
-using Phantom.Utils.Rpc.Frame;
+using Phantom.Utils.Logging;
+using Phantom.Utils.Rpc.Frame;
 using Phantom.Utils.Rpc.Message;
+using Serilog;
 
 namespace Phantom.Utils.Rpc.Runtime.Server;
 
 public sealed class RpcServerToClientConnection<TClientToServerMessage, TServerToClientMessage> {
 	private readonly string loggerName;
+	private readonly ILogger logger;
 	private readonly RpcServerClientSessions<TServerToClientMessage> sessions;
 	private readonly MessageRegistry<TClientToServerMessage> messageRegistry;
+	private readonly MessageReceiveTracker messageReceiveTracker;
 	private readonly Stream stream;
+	private readonly CancellationTokenSource closeCancellationTokenSource = new ();
 	
 	public Guid SessionId { get; }
 	public RpcSendChannel<TServerToClientMessage> SendChannel { get; }
 	
-	internal RpcServerToClientConnection(string loggerName, RpcServerClientSessions<TServerToClientMessage> sessions, Guid sessionId, MessageRegistry<TClientToServerMessage> messageRegistry, Stream stream, RpcSendChannel<TServerToClientMessage> sendChannel) {
+	internal RpcServerToClientConnection(string loggerName, RpcServerClientSessions<TServerToClientMessage> sessions, Guid sessionId, MessageRegistry<TClientToServerMessage> messageRegistry, Stream stream, RpcServerClientSession<TServerToClientMessage> session) {
 		this.loggerName = loggerName;
+		this.logger = PhantomLogger.Create<RpcServerToClientConnection<TClientToServerMessage, TServerToClientMessage>>(loggerName);
 		this.sessions = sessions;
 		this.messageRegistry = messageRegistry;
+		this.messageReceiveTracker = session.MessageReceiveTracker;
 		this.stream = stream;
 		
 		this.SessionId = sessionId;
-		this.SendChannel = sendChannel;
-	}
-	
-	public Task CloseSession() {
-		return sessions.CloseSession(SessionId);
+		this.SendChannel = session.SendChannel;
 	}
 	
 	internal async Task Listen(IMessageReceiver<TClientToServerMessage> receiver) {
 		var messageHandler = new RpcMessageHandler<TClientToServerMessage>(receiver, SendChannel);
-		var frameReader = new RpcFrameReader<TServerToClientMessage, TClientToServerMessage>(loggerName, messageRegistry, messageHandler, SendChannel);
+		var frameReader = new RpcFrameReader<TServerToClientMessage, TClientToServerMessage>(loggerName, messageRegistry, messageReceiveTracker, messageHandler, SendChannel);
 		try {
-			await IFrame.ReadFrom(stream, frameReader, CancellationToken.None);
+			await IFrame.ReadFrom(stream, frameReader, closeCancellationTokenSource.Token);
 		} catch (OperationCanceledException) {
 			// Ignore.
 		}
 	}
+	
+	public async Task ClientClosedSession() {
+		logger.Information("Client closed session.");
+		
+		Task closeSessionTask = sessions.CloseSession(SessionId);
+		await closeCancellationTokenSource.CancelAsync();
+		await closeSessionTask;
+	}
 }

Utils/Phantom.Utils.Tests/Collections/RangeSetTests.cs

@@ -0,0 +1,93 @@
+using NUnit.Framework;
+using Phantom.Utils.Collections;
+using Range = Phantom.Utils.Collections.RangeSet<int>.Range;
+
+namespace Phantom.Utils.Tests.Collections;
+
+[TestFixture]
+public class RangeSetTests {
+	[Test]
+	public void OneValue() {
+		var set = new RangeSet<int>();
+		set.Add(5);
+		
+		Assert.That(set, Is.EqualTo(new[] {
+			new Range(Min: 5, Max: 5),
+		}));
+	}
+	
+	[Test]
+	public void MultipleDisjointValues() {
+		var set = new RangeSet<int>();
+		set.Add(5);
+		set.Add(7);
+		set.Add(1);
+		set.Add(3);
+		
+		Assert.That(set, Is.EqualTo(new[] {
+			new Range(Min: 1, Max: 1),
+			new Range(Min: 3, Max: 3),
+			new Range(Min: 5, Max: 5),
+			new Range(Min: 7, Max: 7),
+		}));
+	}
+	
+	[Test]
+	public void ExtendMin() {
+		var set = new RangeSet<int>();
+		set.Add(5);
+		set.Add(4);
+		
+		Assert.That(set, Is.EqualTo(new[] {
+			new Range(Min: 4, Max: 5),
+		}));
+	}
+	
+	[Test]
+	public void ExtendMax() {
+		var set = new RangeSet<int>();
+		set.Add(5);
+		set.Add(6);
+		
+		Assert.That(set, Is.EqualTo(new[] {
+			new Range(Min: 5, Max: 6),
+		}));
+	}
+	
+	[Test]
+	public void ExtendMaxAndMerge() {
+		var set = new RangeSet<int>();
+		set.Add(5);
+		set.Add(7);
+		set.Add(6);
+		
+		Assert.That(set, Is.EqualTo(new[] {
+			new Range(Min: 5, Max: 7),
+		}));
+	}
+	
+	[Test]
+	public void MultipleMergingAndDisjointValues() {
+		var set = new RangeSet<int>();
+		set.Add(1);
+		set.Add(2);
+		set.Add(5);
+		set.Add(4);
+		set.Add(10);
+		set.Add(7);
+		set.Add(9);
+		set.Add(11);
+		set.Add(16);
+		set.Add(12);
+		set.Add(3);
+		set.Add(14);
+		
+		Assert.That(set, Is.EqualTo(new[] {
+			new Range(Min: 1, Max: 5),
+			new Range(Min: 7, Max: 7),
+			new Range(Min: 9, Max: 12),
+			new Range(Min: 14, Max: 14),
+			new Range(Min: 16, Max: 16),
+		}));
+	}
+}

Utils/Phantom.Utils/Collections/RangeSet.cs

@@ -0,0 +1,69 @@
+using System.Collections;
+using System.Numerics;
+
+namespace Phantom.Utils.Collections;
+
+public sealed class RangeSet<T> : IEnumerable<RangeSet<T>.Range> where T : IBinaryInteger<T> {
+	private readonly List<Range> ranges = [];
+	
+	public bool Add(T value) {
+		int index = 0;
+		
+		for (; index < ranges.Count; index++) {
+			var range = ranges[index];
+			if (range.Contains(value)) {
+				return false;
+			}
+			
+			if (range.ExtendIfAtEdge(value, out var extendedRange)) {
+				ranges[index] = extendedRange;
+				
+				if (index < ranges.Count - 1) {
+					var nextRange = ranges[index + 1];
+					if (extendedRange.Max + T.One == nextRange.Min) {
+						ranges[index] = new Range(extendedRange.Min, nextRange.Max);
+						ranges.RemoveAt(index + 1);
+					}
+				}
+				
+				return true;
+			}
+			
+			if (range.Max > value) {
+				break;
+			}
+		}
+		
+		ranges.Insert(index, new Range(value, value));
+		return true;
+	}
+	
+	public IEnumerator<Range> GetEnumerator() {
+		return ranges.GetEnumerator();
+	}
+	
+	IEnumerator IEnumerable.GetEnumerator() {
+		return GetEnumerator();
+	}
+	
+	public readonly record struct Range(T Min, T Max) {
+		internal bool ExtendIfAtEdge(T value, out Range newRange) {
+			if (value == Min - T.One) {
+				newRange = this with { Min = value };
+				return true;
+			}
+			else if (value == Max + T.One) {
+				newRange = this with { Max = value };
+				return true;
+			}
+			else {
+				newRange = default;
+				return false;
+			}
+		}
+		
+		internal bool Contains(T value) {
+			return value >= Min && value <= Max;
+		}
+	}
+}

Web/Phantom.Web/Program.cs

@@ -93,11 +93,14 @@ try {
 		await shutdownCancellationToken.WaitHandle.WaitOneAsync();
 		await webApplication.StopAsync();
 	} finally {
+		PhantomLogger.Root.Information("Unregistering web...");
 		try {
-			await rpcClient.SendChannel.SendMessage(new UnregisterWebMessage());
-			// TODO wait for acknowledgment
+			using var unregisterCancellationTokenSource = new CancellationTokenSource(TimeSpan.FromSeconds(10));
+			await rpcClient.SendChannel.SendMessage(new UnregisterWebMessage(), unregisterCancellationTokenSource.Token);
+		} catch (OperationCanceledException) {
+			PhantomLogger.Root.Warning("Could not unregister web after shutdown.");
 		} catch (Exception e) {
-			PhantomLogger.Root.Warning(e, "Could not unregister agent after shutdown.");
+			PhantomLogger.Root.Warning(e, "Could not unregister web after shutdown.");
 		} finally {
 			await rpcClient.Shutdown();