Replace NetMQ with custom TCP logic

Agent/Phantom.Agent.Rpc/ControllerConnection.cs

@@ -1,21 +0,0 @@
-using Phantom.Common.Messages.Agent;
-using Phantom.Utils.Logging;
-using Phantom.Utils.Rpc.Runtime;
-using Serilog;
-
-namespace Phantom.Agent.Rpc;
-
-public sealed class ControllerConnection {
-	private static readonly ILogger Logger = PhantomLogger.Create(nameof(ControllerConnection));
-	
-	private readonly RpcConnectionToServer<IMessageToController> connection;
-	
-	public ControllerConnection(RpcConnectionToServer<IMessageToController> connection) {
-		this.connection = connection;
-		Logger.Information("Connection ready.");
-	}
-	
-	public Task Send<TMessage>(TMessage message) where TMessage : IMessageToController {
-		return connection.Send(message);
-	}
-}

Agent/Phantom.Agent.Rpc/KeepAliveLoop.cs

@@ -1,44 +0,0 @@
-using Phantom.Common.Messages.Agent;
-using Phantom.Common.Messages.Agent.ToController;
-using Phantom.Utils.Logging;
-using Phantom.Utils.Rpc.Runtime;
-using Serilog;
-
-namespace Phantom.Agent.Rpc;
-
-sealed class KeepAliveLoop {
-	private static readonly ILogger Logger = PhantomLogger.Create<KeepAliveLoop>();
-	
-	private static readonly TimeSpan KeepAliveInterval = TimeSpan.FromSeconds(10);
-	
-	private readonly RpcConnectionToServer<IMessageToController> connection;
-	private readonly CancellationTokenSource cancellationTokenSource = new ();
-	
-	public KeepAliveLoop(RpcConnectionToServer<IMessageToController> connection) {
-		this.connection = connection;
-		Task.Run(Run);
-	}
-	
-	private async Task Run() {
-		var cancellationToken = cancellationTokenSource.Token;
-		
-		try {
-			await connection.IsReady.WaitAsync(cancellationToken);
-			Logger.Information("Started keep-alive loop.");
-			
-			while (true) {
-				await Task.Delay(KeepAliveInterval, cancellationToken);
-				await connection.Send(new AgentIsAliveMessage()).WaitAsync(cancellationToken);
-			}
-		} catch (OperationCanceledException) {
-			// Ignore.
-		} finally {
-			cancellationTokenSource.Dispose();
-			Logger.Information("Stopped keep-alive loop.");
-		}
-	}
-	
-	public void Cancel() {
-		cancellationTokenSource.Cancel();
-	}
-}

Agent/Phantom.Agent.Rpc/Phantom.Agent.Rpc.csproj

@@ -1,12 +0,0 @@
-<Project Sdk="Microsoft.NET.Sdk">
-  
-  <PropertyGroup>
-    <ImplicitUsings>enable</ImplicitUsings>
-    <Nullable>enable</Nullable>
-  </PropertyGroup>
-  
-  <ItemGroup>
-    <ProjectReference Include="..\..\Common\Phantom.Common.Messages.Agent\Phantom.Common.Messages.Agent.csproj" />
-  </ItemGroup>
-
-</Project>

Agent/Phantom.Agent.Rpc/RpcClientAgentHandshake.cs

@@ -1,7 +0,0 @@
-using Phantom.Common.Data;
-
-namespace Phantom.Agent.Rpc;
-
-sealed class RpcClientAgentHandshake(AuthToken authToken) {
-	
-}

Agent/Phantom.Agent.Rpc/RpcClientRuntime.cs

@@ -1,37 +0,0 @@
-using NetMQ;
-using NetMQ.Sockets;
-using Phantom.Common.Messages.Agent;
-using Phantom.Common.Messages.Agent.BiDirectional;
-using Phantom.Common.Messages.Agent.ToController;
-using Phantom.Utils.Actor;
-using Phantom.Utils.Rpc.Runtime;
-using Phantom.Utils.Rpc.Sockets;
-using Serilog;
-
-namespace Phantom.Agent.Rpc;
-
-public sealed class RpcClientRuntime : RpcClientRuntime<IMessageToAgent, IMessageToController, ReplyMessage> {
-	public static Task Launch(RpcClientSocket<IMessageToAgent, IMessageToController, ReplyMessage> socket, ActorRef<IMessageToAgent> handlerActorRef, SemaphoreSlim disconnectSemaphore, CancellationToken receiveCancellationToken) {
-		return new RpcClientRuntime(socket, handlerActorRef, disconnectSemaphore, receiveCancellationToken).Launch();
-	}
-	
-	private RpcClientRuntime(RpcClientSocket<IMessageToAgent, IMessageToController, ReplyMessage> socket, ActorRef<IMessageToAgent> handlerActor, SemaphoreSlim disconnectSemaphore, CancellationToken receiveCancellationToken) : base(socket, handlerActor, disconnectSemaphore, receiveCancellationToken) {}
-	
-	protected override async Task RunWithConnection(ClientSocket socket, RpcConnectionToServer<IMessageToController> connection) {
-		var keepAliveLoop = new KeepAliveLoop(connection);
-		try {
-			await base.RunWithConnection(socket, connection);
-		} finally {
-			keepAliveLoop.Cancel();
-		}
-	}
-	
-	protected override async Task SendDisconnectMessage(ClientSocket socket, ILogger logger) {
-		var unregisterMessageBytes = AgentMessageRegistries.ToController.Write(new UnregisterAgentMessage()).ToArray();
-		try {
-			await socket.SendAsync(unregisterMessageBytes).AsTask().WaitAsync(TimeSpan.FromSeconds(5), CancellationToken.None);
-		} catch (TimeoutException) {
-			logger.Error("Timed out communicating agent shutdown with the controller.");
-		}
-	}
-}

Agent/Phantom.Agent.Services/AgentServices.cs

@@ -1,9 +1,13 @@
-using Akka.Actor;
+using System.Collections.Immutable;
+using Akka.Actor;
 using Phantom.Agent.Minecraft.Java;
-using Phantom.Agent.Rpc;
 using Phantom.Agent.Services.Backups;
 using Phantom.Agent.Services.Instances;
+using Phantom.Agent.Services.Rpc;
 using Phantom.Common.Data.Agent;
+using Phantom.Common.Data.Replies;
+using Phantom.Common.Messages.Agent.ToAgent;
+using Phantom.Common.Messages.Agent.ToController;
 using Phantom.Utils.Actor;
 using Phantom.Utils.Logging;
 using Serilog;
@@ -15,6 +19,7 @@ public sealed class AgentServices {
 	
 	public ActorSystem ActorSystem { get; }
 	
+	private AgentInfo AgentInfo { get; }
 	private AgentFolders AgentFolders { get; }
 	private AgentState AgentState { get; }
 	private BackupManager BackupManager { get; }
@@ -26,6 +31,7 @@ public sealed class AgentServices {
 	public AgentServices(AgentInfo agentInfo, AgentFolders agentFolders, AgentServiceConfiguration serviceConfiguration, ControllerConnection controllerConnection) {
 		this.ActorSystem = ActorSystemFactory.Create("Agent");
 		
+		this.AgentInfo = agentInfo;
 		this.AgentFolders = agentFolders;
 		this.AgentState = new AgentState();
 		this.BackupManager = new BackupManager(agentFolders, serviceConfiguration.MaxConcurrentCompressionTasks);
@@ -43,6 +49,41 @@ public sealed class AgentServices {
 		}
 	}
 	
+	public  async Task<bool> Register(ControllerConnection connection, 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);
+		} catch (Exception e) {
+			Logger.Fatal(e, "Registration failed.");
+			return false;
+		}
+		
+		foreach (var configureInstanceMessage in configureInstanceMessages) {
+			var configureInstanceCommand = new InstanceManagerActor.ConfigureInstanceCommand(
+				configureInstanceMessage.InstanceGuid,
+				configureInstanceMessage.Configuration,
+				configureInstanceMessage.LaunchProperties,
+				configureInstanceMessage.LaunchNow,
+				AlwaysReportStatus: true
+			);
+			
+			var configureInstanceResult = await InstanceManager.Request(configureInstanceCommand, cancellationToken);
+			if (!configureInstanceResult.Is(ConfigureInstanceResult.Success)) {
+				Logger.Fatal("Unable to configure instance \"{Name}\" (GUID {Guid}), shutting down.", configureInstanceMessage.Configuration.InstanceName, configureInstanceMessage.InstanceGuid);
+				return false;
+			}
+		}
+		
+		await connection.Send(new AdvertiseJavaRuntimesMessage(JavaRuntimeRepository.All), cancellationToken);
+		InstanceTicketManager.RefreshAgentStatus();
+		
+		return true;
+	}
+	
 	public async Task Shutdown() {
 		Logger.Information("Stopping services...");
 		

Agent/Phantom.Agent.Services/Instances/InstanceActor.cs

@@ -58,7 +58,7 @@ sealed class InstanceActor : ReceiveActor<InstanceActor.ICommand> {
 	
 	private void ReportCurrentStatus() {
 		agentState.UpdateInstance(new Instance(instanceGuid, currentStatus));
-		instanceServices.ControllerConnection.Send(new ReportInstanceStatusMessage(instanceGuid, currentStatus));
+		instanceServices.ControllerConnection.TrySend(new ReportInstanceStatusMessage(instanceGuid, currentStatus));
 	}
 	
 	private void TransitionState(InstanceRunningState? newState) {

Agent/Phantom.Agent.Services/Instances/InstanceContext.cs

@@ -7,6 +7,6 @@ namespace Phantom.Agent.Services.Instances;
 
 sealed record InstanceContext(Guid InstanceGuid, string ShortName, ILogger Logger, InstanceServices Services, ActorRef<InstanceActor.ICommand> Actor, CancellationToken ActorCancellationToken) {
 	public void ReportEvent(IInstanceEvent instanceEvent) {
-		Services.ControllerConnection.Send(new ReportInstanceEventMessage(Guid.NewGuid(), DateTime.UtcNow, InstanceGuid, instanceEvent));
+		Services.ControllerConnection.TrySend(new ReportInstanceEventMessage(Guid.NewGuid(), DateTime.UtcNow, InstanceGuid, instanceEvent));
 	}
 }

Agent/Phantom.Agent.Services/Instances/InstanceManagerActor.cs

@@ -4,8 +4,8 @@ using Phantom.Agent.Minecraft.Launcher;
 using Phantom.Agent.Minecraft.Launcher.Types;
 using Phantom.Agent.Minecraft.Properties;
 using Phantom.Agent.Minecraft.Server;
-using Phantom.Agent.Rpc;
 using Phantom.Agent.Services.Backups;
+using Phantom.Agent.Services.Rpc;
 using Phantom.Common.Data;
 using Phantom.Common.Data.Instance;
 using Phantom.Common.Data.Minecraft;
@@ -56,11 +56,6 @@ sealed class InstanceManagerActor : ReceiveActor<InstanceManagerActor.ICommand>
 		ReceiveAsync<ShutdownCommand>(Shutdown);
 	}
 	
-	private string GetInstanceLoggerName(Guid guid) {
-		var prefix = guid.ToString();
-		return prefix[..prefix.IndexOf('-')] + "/" + Interlocked.Increment(ref instanceLoggerSequenceId);
-	}
-	
 	private sealed record InstanceInfo(ActorRef<InstanceActor.ICommand> Actor, InstanceConfiguration Configuration, IServerLauncher Launcher);
 	
 	public interface ICommand {}
@@ -118,7 +113,8 @@ sealed class InstanceManagerActor : ReceiveActor<InstanceManagerActor.ICommand>
 			}
 		}
 		else {
-			var instanceInit = new InstanceActor.Init(agentState, instanceGuid, GetInstanceLoggerName(instanceGuid), instanceServices, instanceTicketManager, shutdownCancellationToken);
+			var instanceLoggerName = PhantomLogger.ShortenGuid(instanceGuid) + "/" + Interlocked.Increment(ref instanceLoggerSequenceId);;
+			var instanceInit = new InstanceActor.Init(agentState, instanceGuid, instanceLoggerName, instanceServices, instanceTicketManager, shutdownCancellationToken);
 			instances[instanceGuid] = instance = new InstanceInfo(Context.ActorOf(InstanceActor.Factory(instanceInit), "Instance-" + instanceGuid), configuration, launcher);
 			
 			Logger.Information("Created instance \"{Name}\" (GUID {Guid}).", configuration.InstanceName, instanceGuid);

Agent/Phantom.Agent.Services/Instances/InstanceServices.cs

@@ -1,6 +1,6 @@
 using Phantom.Agent.Minecraft.Launcher;
-using Phantom.Agent.Rpc;
 using Phantom.Agent.Services.Backups;
+using Phantom.Agent.Services.Rpc;
 
 namespace Phantom.Agent.Services.Instances;
 

Agent/Phantom.Agent.Services/Instances/InstanceTicketManager.cs

@@ -1,4 +1,4 @@
-using Phantom.Agent.Rpc;
+using Phantom.Agent.Services.Rpc;
 using Phantom.Common.Data;
 using Phantom.Common.Data.Agent;
 using Phantom.Common.Data.Instance;
@@ -91,7 +91,7 @@ sealed class InstanceTicketManager {
 	
 	public void RefreshAgentStatus() {
 		lock (this) {
-			controllerConnection.Send(new ReportAgentStatusMessage(activeTicketGuids.Count, usedMemory));
+			controllerConnection.TrySend(new ReportAgentStatusMessage(activeTicketGuids.Count, usedMemory));
 		}
 	}
 	

Agent/Phantom.Agent.Services/Instances/State/InstanceLogSender.cs

@@ -1,6 +1,6 @@
 using System.Collections.Immutable;
 using System.Threading.Channels;
-using Phantom.Agent.Rpc;
+using Phantom.Agent.Services.Rpc;
 using Phantom.Common.Messages.Agent.ToController;
 using Phantom.Utils.Logging;
 using Phantom.Utils.Tasks;
@@ -63,7 +63,7 @@ sealed class InstanceLogSender : CancellableBackgroundTask {
 	
 	private void SendOutputToServer(ImmutableArray<string> lines) {
 		if (!lines.IsEmpty) {
-			controllerConnection.Send(new InstanceOutputMessage(instanceGuid, lines));
+			controllerConnection.TrySend(new InstanceOutputMessage(instanceGuid, lines));
 		}
 	}
 	

Agent/Phantom.Agent.Services/Instances/State/InstancePlayerCountTracker.cs

@@ -1,6 +1,6 @@
 using Phantom.Agent.Minecraft.Instance;
 using Phantom.Agent.Minecraft.Server;
-using Phantom.Agent.Rpc;
+using Phantom.Agent.Services.Rpc;
 using Phantom.Common.Data.Instance;
 using Phantom.Common.Messages.Agent.ToController;
 using Phantom.Utils.Logging;
@@ -38,7 +38,7 @@ sealed class InstancePlayerCountTracker : CancellableBackgroundTask {
 			}
 			
 			onlinePlayerCountChanged?.Invoke(this, value?.Online);
-			controllerConnection.Send(new ReportInstancePlayerCountsMessage(instanceGuid, value));
+			controllerConnection.TrySend(new ReportInstancePlayerCountsMessage(instanceGuid, value));
 		}
 	}
 	

Agent/Phantom.Agent.Services/Phantom.Agent.Services.csproj

@@ -8,7 +8,6 @@
   <ItemGroup>
     <ProjectReference Include="..\..\Common\Phantom.Common.Messages.Agent\Phantom.Common.Messages.Agent.csproj" />
     <ProjectReference Include="..\Phantom.Agent.Minecraft\Phantom.Agent.Minecraft.csproj" />
-    <ProjectReference Include="..\Phantom.Agent.Rpc\Phantom.Agent.Rpc.csproj" />
   </ItemGroup>
 
 </Project>

Agent/Phantom.Agent.Services/Rpc/ControllerConnection.cs

@@ -0,0 +1,20 @@
+using Phantom.Common.Messages.Agent;
+using Phantom.Utils.Actor;
+using Phantom.Utils.Rpc.Runtime;
+
+namespace Phantom.Agent.Services.Rpc;
+
+public sealed class ControllerConnection(RpcSendChannel<IMessageToController> sendChannel) {
+	public ValueTask Send<TMessage>(TMessage message, CancellationToken cancellationToken) where TMessage : IMessageToController {
+		return sendChannel.SendMessage(message, cancellationToken);
+	}
+	
+	// TODO handle properly
+	public bool TrySend<TMessage>(TMessage message) where TMessage : IMessageToController {
+		return sendChannel.TrySendMessage(message);
+	}
+	
+	public Task<TReply> Send<TMessage, TReply>(TMessage message, TimeSpan waitForReplyTime, CancellationToken cancellationToken) where TMessage : IMessageToController, ICanReply<TReply> {
+		return sendChannel.SendMessage<TMessage, TReply>(message, waitForReplyTime, cancellationToken);
+	}
+}

Agent/Phantom.Agent.Services/Rpc/ControllerMessageHandlerActor.cs

@@ -1,86 +1,32 @@
 using Phantom.Agent.Services.Instances;
 using Phantom.Common.Data;
-using Phantom.Common.Data.Instance;
 using Phantom.Common.Data.Replies;
 using Phantom.Common.Messages.Agent;
-using Phantom.Common.Messages.Agent.BiDirectional;
 using Phantom.Common.Messages.Agent.ToAgent;
-using Phantom.Common.Messages.Agent.ToController;
 using Phantom.Utils.Actor;
-using Phantom.Utils.Logging;
-using Phantom.Utils.Rpc.Runtime;
-using Serilog;
 
 namespace Phantom.Agent.Services.Rpc;
 
 public sealed class ControllerMessageHandlerActor : ReceiveActor<IMessageToAgent> {
-	private static ILogger Logger { get; } = PhantomLogger.Create<ControllerMessageHandlerActor>();
-	
-	public readonly record struct Init(RpcConnectionToServer<IMessageToController> Connection, AgentServices Agent, CancellationTokenSource ShutdownTokenSource);
+	public readonly record struct Init(AgentServices Agent);
 	
 	public static Props<IMessageToAgent> Factory(Init init) {
 		return Props<IMessageToAgent>.Create(() => new ControllerMessageHandlerActor(init), new ActorConfiguration { SupervisorStrategy = SupervisorStrategies.Resume });
 	}
 	
-	private readonly RpcConnectionToServer<IMessageToController> connection;
 	private readonly AgentServices agent;
-	private readonly CancellationTokenSource shutdownTokenSource;
 	
 	private ControllerMessageHandlerActor(Init init) {
-		this.connection = init.Connection;
 		this.agent = init.Agent;
-		this.shutdownTokenSource = init.ShutdownTokenSource;
 		
-		ReceiveAsync<RegisterAgentSuccessMessage>(HandleRegisterAgentSuccess);
-		Receive<RegisterAgentFailureMessage>(HandleRegisterAgentFailure);
 		ReceiveAndReplyLater<ConfigureInstanceMessage, Result<ConfigureInstanceResult, InstanceActionFailure>>(HandleConfigureInstance);
 		ReceiveAndReplyLater<LaunchInstanceMessage, Result<LaunchInstanceResult, InstanceActionFailure>>(HandleLaunchInstance);
 		ReceiveAndReplyLater<StopInstanceMessage, Result<StopInstanceResult, InstanceActionFailure>>(HandleStopInstance);
 		ReceiveAndReplyLater<SendCommandToInstanceMessage, Result<SendCommandToInstanceResult, InstanceActionFailure>>(HandleSendCommandToInstance);
-		Receive<ReplyMessage>(HandleReply);
-	}
-	
-	private async Task HandleRegisterAgentSuccess(RegisterAgentSuccessMessage message) {
-		Logger.Information("Agent authentication successful.");
-		
-		void ShutdownAfterConfigurationFailed(Guid instanceGuid, InstanceConfiguration configuration) {
-			Logger.Fatal("Unable to configure instance \"{Name}\" (GUID {Guid}), shutting down.", configuration.InstanceName, instanceGuid);
-			shutdownTokenSource.Cancel();
-		}
-		
-		foreach (var configureInstanceMessage in message.InitialInstanceConfigurations) {
-			var result = await HandleConfigureInstance(configureInstanceMessage, alwaysReportStatus: true);
-			if (!result.Is(ConfigureInstanceResult.Success)) {
-				ShutdownAfterConfigurationFailed(configureInstanceMessage.InstanceGuid, configureInstanceMessage.Configuration);
-				return;
-			}
-		}
-		
-		connection.SetIsReady();
-		
-		await connection.Send(new AdvertiseJavaRuntimesMessage(agent.JavaRuntimeRepository.All));
-		agent.InstanceTicketManager.RefreshAgentStatus();
-	}
-	
-	private void HandleRegisterAgentFailure(RegisterAgentFailureMessage message) {
-		string errorMessage = message.FailureKind switch {
-			RegisterAgentFailure.ConnectionAlreadyHasAnAgent => "This connection already has an associated agent.",
-			RegisterAgentFailure.InvalidToken                => "Invalid token.",
-			_                                                => "Unknown error " + (byte) message.FailureKind + "."
-		};
-		
-		Logger.Fatal("Agent authentication failed: {Error}", errorMessage);
-		
-		PhantomLogger.Dispose();
-		Environment.Exit(1);
-	}
-	
-	private Task<Result<ConfigureInstanceResult, InstanceActionFailure>> HandleConfigureInstance(ConfigureInstanceMessage message, bool alwaysReportStatus) {
-		return agent.InstanceManager.Request(new InstanceManagerActor.ConfigureInstanceCommand(message.InstanceGuid, message.Configuration, message.LaunchProperties, message.LaunchNow, alwaysReportStatus));
 	}
 	
 	private async Task<Result<ConfigureInstanceResult, InstanceActionFailure>> HandleConfigureInstance(ConfigureInstanceMessage message) {
-		return await HandleConfigureInstance(message, alwaysReportStatus: false);
+		return await agent.InstanceManager.Request(new InstanceManagerActor.ConfigureInstanceCommand(message.InstanceGuid, message.Configuration, message.LaunchProperties, message.LaunchNow, AlwaysReportStatus: false));
 	}
 	
 	private async Task<Result<LaunchInstanceResult, InstanceActionFailure>> HandleLaunchInstance(LaunchInstanceMessage message) {
@@ -94,8 +40,4 @@ public sealed class ControllerMessageHandlerActor : ReceiveActor<IMessageToAgent
 	private async Task<Result<SendCommandToInstanceResult, InstanceActionFailure>> HandleSendCommandToInstance(SendCommandToInstanceMessage message) {
 		return await agent.InstanceManager.Request(new InstanceManagerActor.SendCommandToInstanceCommand(message.InstanceGuid, message.Command));
 	}
-	
-	private void HandleReply(ReplyMessage message) {
-		connection.Receive(message);
-	}
 }

Agent/Phantom.Agent/Program.cs

@@ -1,12 +1,16 @@
 using System.Reflection;
 using Phantom.Agent;
-using Phantom.Agent.Rpc;
 using Phantom.Agent.Services;
+using Phantom.Agent.Services.Rpc;
 using Phantom.Common.Data.Agent;
 using Phantom.Common.Messages.Agent;
+using Phantom.Common.Messages.Agent.ToController;
+using Phantom.Utils.Actor;
 using Phantom.Utils.Logging;
-using Phantom.Utils.Rpc.New;
+using Phantom.Utils.Rpc.Message;
+using Phantom.Utils.Rpc.Runtime.Client;
 using Phantom.Utils.Runtime;
+using Phantom.Utils.Threading;
 
 const int ProtocolVersion = 1;
 
@@ -43,46 +47,56 @@ try {
 		return 1;
 	}
 	
-	var (certificateThumbprint, authToken) = agentKey.Value;
-	var agentInfo = new AgentInfo(agentGuid.Value, agentName, ProtocolVersion, fullVersion, maxInstances, maxMemory, allowedServerPorts, allowedRconPorts);
+	var rpcClientConnectionParameters = new RpcClientConnectionParameters(
+		Host: controllerHost,
+		Port: controllerPort,
+		DistinguishedName: "phantom-controller",
+		CertificateThumbprint: agentKey.Value.CertificateThumbprint,
+		AuthToken: agentKey.Value.AuthToken,
+		SendQueueCapacity: 500,
+		PingInterval: TimeSpan.FromSeconds(10)
+	);
 	
-	PhantomLogger.Root.InformationHeading("Launching Phantom Panel agent...");
-	
-	var rpcClient = new RpcClient<IMessageToController, IMessageToAgent>("Controller", controllerHost, controllerPort, "phantom-controller", certificateThumbprint, null);
-	var rpcConnection = await rpcClient.Connect(shutdownCancellationToken);
-	if (rpcConnection == null) {
+	using var rpcClient = await RpcClient<IMessageToController, IMessageToAgent>.Connect("Controller", rpcClientConnectionParameters, AgentMessageRegistries.Definitions, shutdownCancellationToken);
+	if (rpcClient == null) {
 		return 1;
 	}
 	
-	// var rpcConfiguration = new RpcConfiguration("Agent", controllerHost, controllerPort, controllerCertificate);
-	// var rpcSocket = RpcClientSocket.Connect(rpcConfiguration, AgentMessageRegistries.Definitions, new RegisterAgentMessage(agentToken, agentInfo));
-	//
-	var agentServices = new AgentServices(agentInfo, folders, new AgentServiceConfiguration(maxConcurrentBackupCompressionTasks), new ControllerConnection(rpcSocket.Connection));
-	await agentServices.Initialize();
+	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);
+		await agentServices.Initialize();
+		
+		var rpcMessageHandlerInit = new ControllerMessageHandlerActor.Init(agentServices);
+		var rpcMessageHandlerActor = agentServices.ActorSystem.ActorOf(ControllerMessageHandlerActor.Factory(rpcMessageHandlerInit), "ControllerMessageHandler");
+		
+		rpcClientListener = rpcClient.Listen(new IMessageReceiver<IMessageToAgent>.Actor(rpcMessageHandlerActor));
+		
+		if (await agentServices.Register(controllerConnection, shutdownCancellationToken)) {
+			PhantomLogger.Root.Information("Phantom Panel agent is ready.");
+			await shutdownCancellationToken.WaitHandle.WaitOneAsync();
+		}
 		
-	} finally {
 		await agentServices.Shutdown();
+	} finally {
+		try {
+			await controllerConnection.Send(new UnregisterAgentMessage(), CancellationToken.None);
+			// TODO wait for acknowledgment
+		} catch (Exception e) {
+			PhantomLogger.Root.Warning(e, "Could not unregister agent after shutdown.");
+		} finally {
+			await rpcClient.Shutdown();
+			
+			if (rpcClientListener != null) {
+				await rpcClientListener;
+			}
+		}
 	}
-	//
-	// var rpcMessageHandlerInit = new ControllerMessageHandlerActor.Init(rpcSocket.Connection, agentServices, shutdownCancellationTokenSource);
-	// var rpcMessageHandlerActor = agentServices.ActorSystem.ActorOf(ControllerMessageHandlerActor.Factory(rpcMessageHandlerInit), "ControllerMessageHandler");
-	//
-	// var rpcDisconnectSemaphore = new SemaphoreSlim(0, 1);
-	// var rpcTask = RpcClientRuntime.Launch(rpcSocket, rpcMessageHandlerActor, rpcDisconnectSemaphore, shutdownCancellationToken);
-	// try {
-	// 	await rpcTask.WaitAsync(shutdownCancellationToken);
-	// } finally {
-	// 	shutdownCancellationTokenSource.Cancel();
-	// 	await agentServices.Shutdown();
-	// 	
-	// 	rpcDisconnectSemaphore.Release();
-	// 	await rpcTask;
-	// 	rpcDisconnectSemaphore.Dispose();
-	// 	
-	// 	NetMQConfig.Cleanup();
-	// }
 	
 	return 0;
 } catch (OperationCanceledException) {

Common/Phantom.Common.Data/ConnectionKey.cs

@@ -1,4 +1,5 @@
-using Phantom.Utils.Rpc.New;
+using Phantom.Utils.Rpc;
+using Phantom.Utils.Rpc.Runtime.Tls;
 
 namespace Phantom.Common.Data;
 
@@ -7,7 +8,7 @@ public readonly record struct ConnectionKey(RpcCertificateThumbprint Certificate
 
 	public byte[] ToBytes() {
 		Span<byte> result = stackalloc byte[TokenLength + CertificateThumbprint.Bytes.Length];
-		AuthToken.WriteTo(result[..TokenLength]);
+		AuthToken.Bytes.CopyTo(result[..TokenLength]);
 		CertificateThumbprint.Bytes.CopyTo(result[TokenLength..]);
 		return result.ToArray();
 	}

Common/Phantom.Common.Data/Replies/RegisterAgentFailure.cs

@@ -1,6 +0,0 @@
-namespace Phantom.Common.Data.Replies;
-
-public enum RegisterAgentFailure : byte {
-	ConnectionAlreadyHasAnAgent,
-	InvalidToken
-}

Common/Phantom.Common.Data/Result.cs

@@ -1,5 +1,6 @@
 using System.Diagnostics.CodeAnalysis;
 using MemoryPack;
+using Phantom.Utils.Monads;
 using Phantom.Utils.Result;
 
 namespace Phantom.Common.Data;
@@ -24,6 +25,9 @@ public sealed partial class Result<TValue, TError> {
 	[MemoryPackIgnore]
 	public TError Error => !hasValue ? error! : throw new InvalidOperationException("Attempted to get error from a success result.");
 	
+	[MemoryPackIgnore]
+	public Either<TValue, TError> AsEither => hasValue ? Either.Left(value!) : Either.Right(error!);
+	
 	private Result(bool hasValue, TValue? value, TError? error) {
 		this.hasValue = hasValue;
 		this.value = value;

Common/Phantom.Common.Messages.Agent/AgentMessageRegistries.cs

@@ -1,6 +1,6 @@
-using Phantom.Common.Data;
+using System.Collections.Immutable;
+using Phantom.Common.Data;
 using Phantom.Common.Data.Replies;
-using Phantom.Common.Messages.Agent.BiDirectional;
 using Phantom.Common.Messages.Agent.ToAgent;
 using Phantom.Common.Messages.Agent.ToController;
 using Phantom.Utils.Logging;
@@ -12,35 +12,26 @@ public static class AgentMessageRegistries {
 	public static MessageRegistry<IMessageToAgent> ToAgent { get; } = new (PhantomLogger.Create("MessageRegistry", nameof(ToAgent)));
 	public static MessageRegistry<IMessageToController> ToController { get; } = new (PhantomLogger.Create("MessageRegistry", nameof(ToController)));
 	
-	public static IMessageDefinitions<IMessageToAgent, IMessageToController, ReplyMessage> Definitions { get; } = new MessageDefinitions();
+	public static IMessageDefinitions<IMessageToController, IMessageToAgent> Definitions { get; } = new MessageDefinitions();
 	
 	static AgentMessageRegistries() {
-		ToAgent.Add<RegisterAgentSuccessMessage>(0);
-		ToAgent.Add<RegisterAgentFailureMessage>(1);
 		ToAgent.Add<ConfigureInstanceMessage, Result<ConfigureInstanceResult, InstanceActionFailure>>(2);
 		ToAgent.Add<LaunchInstanceMessage, Result<LaunchInstanceResult, InstanceActionFailure>>(3);
 		ToAgent.Add<StopInstanceMessage, Result<StopInstanceResult, InstanceActionFailure>>(4);
 		ToAgent.Add<SendCommandToInstanceMessage, Result<SendCommandToInstanceResult, InstanceActionFailure>>(5);
-		ToAgent.Add<ReplyMessage>(127);
 		
-		ToController.Add<RegisterAgentMessage>(0);
+		ToController.Add<RegisterAgentMessage, ImmutableArray<ConfigureInstanceMessage>>(0);
 		ToController.Add<UnregisterAgentMessage>(1);
-		ToController.Add<AgentIsAliveMessage>(2);
 		ToController.Add<AdvertiseJavaRuntimesMessage>(3);
 		ToController.Add<ReportInstanceStatusMessage>(4);
 		ToController.Add<InstanceOutputMessage>(5);
 		ToController.Add<ReportAgentStatusMessage>(6);
 		ToController.Add<ReportInstanceEventMessage>(7);
 		ToController.Add<ReportInstancePlayerCountsMessage>(8);
-		ToController.Add<ReplyMessage>(127);
 	}
 	
-	private sealed class MessageDefinitions : IMessageDefinitions<IMessageToAgent, IMessageToController, ReplyMessage> {
+	private sealed class MessageDefinitions : IMessageDefinitions<IMessageToController, IMessageToAgent> {
 		public MessageRegistry<IMessageToAgent> ToClient => ToAgent;
 		public MessageRegistry<IMessageToController> ToServer => ToController;
-		
-		public ReplyMessage CreateReplyMessage(uint sequenceId, byte[] serializedReply) {
-			return new ReplyMessage(sequenceId, serializedReply);
-		}
 	}
 }

Common/Phantom.Common.Messages.Agent/BiDirectional/ReplyMessage.cs

@@ -1,10 +0,0 @@
-using MemoryPack;
-using Phantom.Utils.Rpc.Message;
-
-namespace Phantom.Common.Messages.Agent.BiDirectional;
-
-[MemoryPackable(GenerateType.VersionTolerant)]
-public sealed partial record ReplyMessage(
-	[property: MemoryPackOrder(0)] uint SequenceId,
-	[property: MemoryPackOrder(1)] byte[] SerializedReply
-) : IMessageToController, IMessageToAgent, IReply;

Common/Phantom.Common.Messages.Agent/ToAgent/RegisterAgentFailureMessage.cs

@@ -1,9 +0,0 @@
-using MemoryPack;
-using Phantom.Common.Data.Replies;
-
-namespace Phantom.Common.Messages.Agent.ToAgent;
-
-[MemoryPackable(GenerateType.VersionTolerant)]
-public sealed partial record RegisterAgentFailureMessage(
-	[property: MemoryPackOrder(0)] RegisterAgentFailure FailureKind
-) : IMessageToAgent;

Common/Phantom.Common.Messages.Agent/ToAgent/RegisterAgentSuccessMessage.cs

@@ -1,9 +0,0 @@
-using System.Collections.Immutable;
-using MemoryPack;
-
-namespace Phantom.Common.Messages.Agent.ToAgent;
-
-[MemoryPackable(GenerateType.VersionTolerant)]
-public sealed partial record RegisterAgentSuccessMessage(
-	[property: MemoryPackOrder(0)] ImmutableArray<ConfigureInstanceMessage> InitialInstanceConfigurations
-) : IMessageToAgent;

Common/Phantom.Common.Messages.Agent/ToController/AgentIsAliveMessage.cs

@@ -1,6 +0,0 @@
-using MemoryPack;
-
-namespace Phantom.Common.Messages.Agent.ToController;
-
-[MemoryPackable(GenerateType.VersionTolerant)]
-public sealed partial record AgentIsAliveMessage : IMessageToController;

Common/Phantom.Common.Messages.Agent/ToController/RegisterAgentMessage.cs

@@ -1,11 +1,12 @@
-using MemoryPack;
-using Phantom.Common.Data;
+using System.Collections.Immutable;
+using MemoryPack;
 using Phantom.Common.Data.Agent;
+using Phantom.Common.Messages.Agent.ToAgent;
+using Phantom.Utils.Actor;
 
 namespace Phantom.Common.Messages.Agent.ToController;
 
 [MemoryPackable(GenerateType.VersionTolerant)]
 public sealed partial record RegisterAgentMessage(
-	[property: MemoryPackOrder(0)] AuthToken AuthToken,
-	[property: MemoryPackOrder(1)] AgentInfo AgentInfo
-) : IMessageToController;
+	[property: MemoryPackOrder(0)] AgentInfo AgentInfo
+) : IMessageToController, ICanReply<ImmutableArray<ConfigureInstanceMessage>>;

Common/Phantom.Common.Messages.Web/BiDirectional/ReplyMessage.cs

@@ -1,10 +0,0 @@
-using MemoryPack;
-using Phantom.Utils.Rpc.Message;
-
-namespace Phantom.Common.Messages.Web.BiDirectional;
-
-[MemoryPackable(GenerateType.VersionTolerant)]
-public sealed partial record ReplyMessage(
-	[property: MemoryPackOrder(0)] uint SequenceId,
-	[property: MemoryPackOrder(1)] byte[] SerializedReply
-) : IMessageToController, IMessageToWeb, IReply;

Common/Phantom.Common.Messages.Web/ToController/RegisterWebMessage.cs

@@ -1,9 +0,0 @@
-using MemoryPack;
-using Phantom.Common.Data;
-
-namespace Phantom.Common.Messages.Web.ToController;
-
-[MemoryPackable(GenerateType.VersionTolerant)]
-public sealed partial record RegisterWebMessage(
-	[property: MemoryPackOrder(0)] AuthToken AuthToken
-) : IMessageToController;

Common/Phantom.Common.Messages.Web/ToWeb/RegisterWebResultMessage.cs

@@ -1,8 +0,0 @@
-using MemoryPack;
-
-namespace Phantom.Common.Messages.Web.ToWeb;
-
-[MemoryPackable(GenerateType.VersionTolerant)]
-public sealed partial record RegisterWebResultMessage(
-	[property: MemoryPackOrder(0)] bool Success
-) : IMessageToWeb;

Common/Phantom.Common.Messages.Web/WebMessageRegistries.cs

@@ -7,7 +7,6 @@ using Phantom.Common.Data.Web.AuditLog;
 using Phantom.Common.Data.Web.EventLog;
 using Phantom.Common.Data.Web.Instance;
 using Phantom.Common.Data.Web.Users;
-using Phantom.Common.Messages.Web.BiDirectional;
 using Phantom.Common.Messages.Web.ToController;
 using Phantom.Common.Messages.Web.ToWeb;
 using Phantom.Utils.Logging;
@@ -19,10 +18,9 @@ public static class WebMessageRegistries {
 	public static MessageRegistry<IMessageToController> ToController { get; } = new (PhantomLogger.Create("MessageRegistry", nameof(ToController)));
 	public static MessageRegistry<IMessageToWeb> ToWeb { get; } = new (PhantomLogger.Create("MessageRegistry", nameof(ToWeb)));
 	
-	public static IMessageDefinitions<IMessageToWeb, IMessageToController, ReplyMessage> Definitions { get; } = new MessageDefinitions();
+	public static IMessageDefinitions<IMessageToController, IMessageToWeb> Definitions { get; } = new MessageDefinitions();
 	
 	static WebMessageRegistries() {
-		ToController.Add<RegisterWebMessage>(0);
 		ToController.Add<UnregisterWebMessage>(1);
 		ToController.Add<LogInMessage, Optional<LogInSuccess>>(2);
 		ToController.Add<LogOutMessage>(3);
@@ -42,22 +40,15 @@ public static class WebMessageRegistries {
 		ToController.Add<GetAgentJavaRuntimesMessage, ImmutableDictionary<Guid, ImmutableArray<TaggedJavaRuntime>>>(17);
 		ToController.Add<GetAuditLogMessage, Result<ImmutableArray<AuditLogItem>, UserActionFailure>>(18);
 		ToController.Add<GetEventLogMessage, Result<ImmutableArray<EventLogItem>, UserActionFailure>>(19);
-		ToController.Add<ReplyMessage>(127);
 		
-		ToWeb.Add<RegisterWebResultMessage>(0);
 		ToWeb.Add<RefreshAgentsMessage>(1);
 		ToWeb.Add<RefreshInstancesMessage>(2);
 		ToWeb.Add<InstanceOutputMessage>(3);
 		ToWeb.Add<RefreshUserSessionMessage>(4);
-		ToWeb.Add<ReplyMessage>(127);
 	}
 	
-	private sealed class MessageDefinitions : IMessageDefinitions<IMessageToWeb, IMessageToController, ReplyMessage> {
+	private sealed class MessageDefinitions : IMessageDefinitions<IMessageToController, IMessageToWeb> {
 		public MessageRegistry<IMessageToWeb> ToClient => ToWeb;
 		public MessageRegistry<IMessageToController> ToServer => ToController;
-		
-		public ReplyMessage CreateReplyMessage(uint sequenceId, byte[] serializedReply) {
-			return new ReplyMessage(sequenceId, serializedReply);
-		}
 	}
 }

Controller/Phantom.Controller.Services/Agents/AgentActor.cs

@@ -21,7 +21,7 @@ using Phantom.Utils.Actor.Mailbox;
 using Phantom.Utils.Actor.Tasks;
 using Phantom.Utils.Collections;
 using Phantom.Utils.Logging;
-using Phantom.Utils.Rpc.Runtime;
+using Phantom.Utils.Rpc.Runtime.Server;
 using Serilog;
 
 namespace Phantom.Controller.Services.Agents;
@@ -168,13 +168,13 @@ sealed class AgentActor : ReceiveActor<AgentActor.ICommand> {
 		return configurationMessages.ToImmutable();
 	}
 	
-	public interface ICommand {}
+	public interface ICommand;
 	
 	private sealed record InitializeCommand : ICommand;
 	
-	public sealed record RegisterCommand(AgentConfiguration Configuration, RpcConnectionToClient<IMessageToAgent> Connection) : ICommand, ICanReply<ImmutableArray<ConfigureInstanceMessage>>;
+	public sealed record RegisterCommand(AgentConfiguration Configuration, RpcServerToClientConnection<IMessageToController, IMessageToAgent> Connection) : ICommand, ICanReply<ImmutableArray<ConfigureInstanceMessage>>;
 	
-	public sealed record UnregisterCommand(RpcConnectionToClient<IMessageToAgent> Connection) : ICommand;
+	public sealed record UnregisterCommand(RpcServerToClientConnection<IMessageToController, IMessageToAgent> Connection) : ICommand;
 	
 	private sealed record RefreshConnectionStatusCommand : ICommand;
 	

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

@@ -1,36 +1,30 @@
 using Phantom.Common.Messages.Agent;
 using Phantom.Utils.Actor;
 using Phantom.Utils.Logging;
-using Phantom.Utils.Rpc.Runtime;
+using Phantom.Utils.Rpc.Runtime.Server;
 using Serilog;
 
 namespace Phantom.Controller.Services.Agents;
 
-sealed class AgentConnection {
+sealed class AgentConnection(Guid agentGuid, string agentName) {
 	private static readonly ILogger Logger = PhantomLogger.Create<AgentConnection>();
 	
-	private readonly Guid agentGuid;
-	private string agentName;
+	private string agentName = agentName;
+	private RpcServerToClientConnection<IMessageToController, IMessageToAgent>? connection;
 	
-	private RpcConnectionToClient<IMessageToAgent>? connection;
-	
-	public AgentConnection(Guid agentGuid, string agentName) {
-		this.agentName = agentName;
-		this.agentGuid = agentGuid;
-	}
-	
-	public void UpdateConnection(RpcConnectionToClient<IMessageToAgent> newConnection, string newAgentName) {
+	public void UpdateConnection(RpcServerToClientConnection<IMessageToController, IMessageToAgent> newConnection, string newAgentName) {
 		lock (this) {
-			connection?.Close();
+			connection?.CloseSession();
 			connection = newConnection;
 			agentName = newAgentName;
 		}
 	}
 	
-	public bool CloseIfSame(RpcConnectionToClient<IMessageToAgent> expected) {
+	public bool CloseIfSame(RpcServerToClientConnection<IMessageToController, IMessageToAgent> expected) {
 		lock (this) {
-			if (connection != null && connection.IsSame(expected)) {
-				connection.Close();
+			if (connection != null && ReferenceEquals(connection, expected)) {
+				connection.CloseSession();
+				connection = null;
 				return true;
 			}
 		}
@@ -45,7 +39,7 @@ sealed class AgentConnection {
 				return Task.CompletedTask;
 			}
 			
-			return connection.Send(message);
+			return connection.SendChannel.SendMessage(message).AsTask();
 		}
 	}
 	
@@ -53,10 +47,10 @@ sealed class AgentConnection {
 		lock (this) {
 			if (connection == null) {
 				LogAgentOffline();
-				return Task.FromResult<TReply?>(default);
+				return Task.FromResult<TReply?>(null);
 			}
 			
-			return connection.Send<TMessage, TReply>(message, waitForReplyTime, waitForReplyCancellationToken)!;
+			return connection.SendChannel.SendMessage<TMessage, TReply>(message, waitForReplyTime, waitForReplyCancellationToken)!;
 		}
 	}
 	

Controller/Phantom.Controller.Services/Agents/AgentManager.cs

@@ -13,7 +13,7 @@ using Phantom.Controller.Minecraft;
 using Phantom.Controller.Services.Users.Sessions;
 using Phantom.Utils.Actor;
 using Phantom.Utils.Logging;
-using Phantom.Utils.Rpc.Runtime;
+using Phantom.Utils.Rpc.Runtime.Server;
 using Serilog;
 
 namespace Phantom.Controller.Services.Agents;
@@ -22,19 +22,18 @@ sealed class AgentManager {
 	private static readonly ILogger Logger = PhantomLogger.Create<AgentManager>();
 	
 	private readonly IActorRefFactory actorSystem;
-	private readonly AuthToken authToken;
 	private readonly ControllerState controllerState;
 	private readonly MinecraftVersions minecraftVersions;
 	private readonly UserLoginManager userLoginManager;
 	private readonly IDbContextProvider dbProvider;
 	private readonly CancellationToken cancellationToken;
 	
-	private readonly ConcurrentDictionary<Guid, ActorRef<AgentActor.ICommand>> agentsByGuid = new ();
+	private readonly ConcurrentDictionary<Guid, ActorRef<AgentActor.ICommand>> agentsByAgentGuid = new ();
+	private readonly ConcurrentDictionary<Guid, Guid> agentGuidsBySessionGuid = new ();
 	private readonly Func<Guid, AgentConfiguration, ActorRef<AgentActor.ICommand>> addAgentActorFactory;
 	
-	public AgentManager(IActorRefFactory actorSystem, AuthToken authToken, ControllerState controllerState, MinecraftVersions minecraftVersions, UserLoginManager userLoginManager, IDbContextProvider dbProvider, CancellationToken cancellationToken) {
+	public AgentManager(IActorRefFactory actorSystem, ControllerState controllerState, MinecraftVersions minecraftVersions, UserLoginManager userLoginManager, IDbContextProvider dbProvider, CancellationToken cancellationToken) {
 		this.actorSystem = actorSystem;
-		this.authToken = authToken;
 		this.controllerState = controllerState;
 		this.minecraftVersions = minecraftVersions;
 		this.userLoginManager = userLoginManager;
@@ -57,28 +56,21 @@ sealed class AgentManager {
 			var agentGuid = entity.AgentGuid;
 			var agentConfiguration = new AgentConfiguration(entity.Name, entity.ProtocolVersion, entity.BuildVersion, entity.MaxInstances, entity.MaxMemory);
 			
-			if (agentsByGuid.TryAdd(agentGuid, CreateAgentActor(agentGuid, agentConfiguration))) {
+			if (agentsByAgentGuid.TryAdd(agentGuid, CreateAgentActor(agentGuid, agentConfiguration))) {
 				Logger.Information("Loaded agent \"{AgentName}\" (GUID {AgentGuid}) from database.", agentConfiguration.AgentName, agentGuid);
 			}
 		}
 	}
 	
-	public async Task<bool> RegisterAgent(AuthToken authToken, AgentInfo agentInfo, RpcConnectionToClient<IMessageToAgent> connection) {
-		if (!this.authToken.FixedTimeEquals(authToken)) {
-			await connection.Send(new RegisterAgentFailureMessage(RegisterAgentFailure.InvalidToken));
-			return false;
-		}
-		
+	public async Task<ImmutableArray<ConfigureInstanceMessage>> RegisterAgent(AgentInfo agentInfo, RpcServerToClientConnection<IMessageToController, IMessageToAgent> connection) {
 		var agentProperties = AgentConfiguration.From(agentInfo);
-		var agentActor = agentsByGuid.GetOrAdd(agentInfo.AgentGuid, addAgentActorFactory, agentProperties);
-		var configureInstanceMessages = await agentActor.Request(new AgentActor.RegisterCommand(agentProperties, connection), cancellationToken);
-		await connection.Send(new RegisterAgentSuccessMessage(configureInstanceMessages));
-		
-		return true;
+		var agentActor = agentsByAgentGuid.GetOrAdd(agentInfo.AgentGuid, addAgentActorFactory, agentProperties);
+		agentGuidsBySessionGuid[connection.SessionId] = agentInfo.AgentGuid;
+		return await agentActor.Request(new AgentActor.RegisterCommand(agentProperties, connection), cancellationToken);
 	}
 	
 	public bool TellAgent(Guid agentGuid, AgentActor.ICommand command) {
-		if (agentsByGuid.TryGetValue(agentGuid, out var agent)) {
+		if (agentsByAgentGuid.TryGetValue(agentGuid, out var agent)) {
 			agent.Tell(command);
 			return true;
 		}
@@ -94,7 +86,7 @@ sealed class AgentManager {
 			return (UserInstanceActionFailure) UserActionFailure.NotAuthorized;
 		}
 		
-		if (!agentsByGuid.TryGetValue(agentGuid, out var agent)) {
+		if (!agentsByAgentGuid.TryGetValue(agentGuid, out var agent)) {
 			return (UserInstanceActionFailure) InstanceActionFailure.AgentDoesNotExist;
 		}
 		
@@ -102,4 +94,12 @@ sealed class AgentManager {
 		var result = await agent.Request(command, cancellationToken);
 		return result.MapError(static error => (UserInstanceActionFailure) error);
 	}
+	
+	public bool TryGetAgentGuidBySessionGuid(Guid sessionGuid, out Guid agentGuid) {
+		return agentGuidsBySessionGuid.TryGetValue(sessionGuid, out agentGuid);
+	}
+	
+	public void OnSessionClosed(Guid sessionId, Guid agentGuid) {
+		agentGuidsBySessionGuid.TryRemove(new KeyValuePair<Guid, Guid>(sessionId, agentGuid));
+	}
 }

Controller/Phantom.Controller.Services/ControllerServices.cs

@@ -1,9 +1,4 @@
 using Akka.Actor;
-using Phantom.Common.Data;
-using Phantom.Common.Messages.Agent;
-using Phantom.Common.Messages.Agent.ToController;
-using Phantom.Common.Messages.Web;
-using Phantom.Common.Messages.Web.ToController;
 using Phantom.Controller.Database;
 using Phantom.Controller.Minecraft;
 using Phantom.Controller.Services.Agents;
@@ -13,9 +8,9 @@ using Phantom.Controller.Services.Rpc;
 using Phantom.Controller.Services.Users;
 using Phantom.Controller.Services.Users.Sessions;
 using Phantom.Utils.Actor;
-using Phantom.Utils.Rpc.Runtime;
-using IMessageFromAgentToController = Phantom.Common.Messages.Agent.IMessageToController;
-using IMessageFromWebToController = Phantom.Common.Messages.Web.IMessageToController;
+using Phantom.Utils.Rpc;
+using IRpcAgentRegistrar = Phantom.Utils.Rpc.Runtime.Server.IRpcServerClientRegistrar<Phantom.Common.Messages.Agent.IMessageToController, Phantom.Common.Messages.Agent.IMessageToAgent>;
+using IRpcWebRegistrar = Phantom.Utils.Rpc.Runtime.Server.IRpcServerClientRegistrar<Phantom.Common.Messages.Web.IMessageToController, Phantom.Common.Messages.Web.IMessageToWeb>;
 
 namespace Phantom.Controller.Services;
 
@@ -38,13 +33,13 @@ public sealed class ControllerServices : IDisposable {
 	private AuditLogManager AuditLogManager { get; }
 	private EventLogManager EventLogManager { get; }
 	
-	public IRegistrationHandler<IMessageToAgent, IMessageFromAgentToController, RegisterAgentMessage> AgentRegistrationHandler { get; }
-	public IRegistrationHandler<IMessageToWeb, IMessageFromWebToController, RegisterWebMessage> WebRegistrationHandler { get; }
+	public IRpcAgentRegistrar AgentRegistrar { get; }
+	public IRpcWebRegistrar WebRegistrar { get; }
 	
 	private readonly IDbContextProvider dbProvider;
 	private readonly CancellationToken cancellationToken;
 	
-	public ControllerServices(IDbContextProvider dbProvider, AuthToken agentAuthToken, AuthToken webAuthToken, CancellationToken shutdownCancellationToken) {
+	public ControllerServices(IDbContextProvider dbProvider, AuthToken agentAuthToken, CancellationToken shutdownCancellationToken) {
 		this.dbProvider = dbProvider;
 		this.cancellationToken = shutdownCancellationToken;
 		
@@ -60,14 +55,14 @@ public sealed class ControllerServices : IDisposable {
 		this.UserLoginManager = new UserLoginManager(AuthenticatedUserCache, UserManager, dbProvider);
 		this.PermissionManager = new PermissionManager(dbProvider);
 		
-		this.AgentManager = new AgentManager(ActorSystem, agentAuthToken, ControllerState, MinecraftVersions, UserLoginManager, dbProvider, cancellationToken);
+		this.AgentManager = new AgentManager(ActorSystem, ControllerState, MinecraftVersions, UserLoginManager, dbProvider, cancellationToken);
 		this.InstanceLogManager = new InstanceLogManager();
 		
 		this.AuditLogManager = new AuditLogManager(dbProvider);
 		this.EventLogManager = new EventLogManager(ControllerState, ActorSystem, dbProvider, shutdownCancellationToken);
 		
-		this.AgentRegistrationHandler = new AgentRegistrationHandler(AgentManager, InstanceLogManager, EventLogManager);
-		this.WebRegistrationHandler = new WebRegistrationHandler(webAuthToken, ControllerState, InstanceLogManager, UserManager, RoleManager, UserRoleManager, UserLoginManager, AuditLogManager, AgentManager, MinecraftVersions, EventLogManager);
+		this.AgentRegistrar = new AgentClientRegistrar(ActorSystem, AgentManager, InstanceLogManager, EventLogManager);
+		this.WebRegistrar = new WebClientRegistrar(ActorSystem, ControllerState, InstanceLogManager, UserManager, RoleManager, UserRoleManager, UserLoginManager, AuditLogManager, AgentManager, MinecraftVersions, EventLogManager);
 	}
 	
 	public async Task Initialize() {

Controller/Phantom.Controller.Services/Rpc/AgentClientRegistrar.cs

@@ -0,0 +1,31 @@
+using Akka.Actor;
+using Phantom.Common.Messages.Agent;
+using Phantom.Controller.Services.Agents;
+using Phantom.Controller.Services.Events;
+using Phantom.Controller.Services.Instances;
+using Phantom.Utils.Actor;
+using Phantom.Utils.Rpc.Message;
+using Phantom.Utils.Rpc.Runtime.Server;
+
+namespace Phantom.Controller.Services.Rpc;
+
+sealed class AgentClientRegistrar(
+	IActorRefFactory actorSystem,
+	AgentManager agentManager,
+	InstanceLogManager instanceLogManager,
+	EventLogManager eventLogManager
+) : IRpcServerClientRegistrar<IMessageToController, IMessageToAgent> {
+	public IMessageReceiver<IMessageToController> Register(RpcServerToClientConnection<IMessageToController, IMessageToAgent> connection) {
+		var name = "AgentClient-" + connection.SessionId;
+		var init = new AgentMessageHandlerActor.Init(connection, agentManager, instanceLogManager, eventLogManager);
+		return new Receiver(connection.SessionId, agentManager, actorSystem.ActorOf(AgentMessageHandlerActor.Factory(init), name));
+	}
+	
+	private sealed class Receiver(Guid sessionId, AgentManager agentManager, ActorRef<IMessageToController> actor) : IMessageReceiver<IMessageToController>.Actor(actor) {
+		public override void OnPing() {
+			if (agentManager.TryGetAgentGuidBySessionGuid(sessionId, out var agentGuid)) {
+				agentManager.TellAgent(agentGuid, new AgentActor.NotifyIsAliveCommand());
+			}
+		}
+	}
+}

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

@@ -1,93 +1,82 @@
-using Phantom.Common.Data.Replies;
+using System.Collections.Immutable;
 using Phantom.Common.Messages.Agent;
-using Phantom.Common.Messages.Agent.BiDirectional;
 using Phantom.Common.Messages.Agent.ToAgent;
 using Phantom.Common.Messages.Agent.ToController;
 using Phantom.Controller.Services.Agents;
 using Phantom.Controller.Services.Events;
 using Phantom.Controller.Services.Instances;
 using Phantom.Utils.Actor;
-using Phantom.Utils.Rpc.Runtime;
+using Phantom.Utils.Rpc.Runtime.Server;
 
 namespace Phantom.Controller.Services.Rpc;
 
 sealed class AgentMessageHandlerActor : ReceiveActor<IMessageToController> {
-	public readonly record struct Init(Guid AgentGuid, RpcConnectionToClient<IMessageToAgent> Connection, AgentRegistrationHandler AgentRegistrationHandler, AgentManager AgentManager, InstanceLogManager InstanceLogManager, EventLogManager EventLogManager);
+	public readonly record struct Init(RpcServerToClientConnection<IMessageToController, IMessageToAgent> Connection, AgentManager AgentManager, InstanceLogManager InstanceLogManager, EventLogManager EventLogManager);
 	
 	public static Props<IMessageToController> Factory(Init init) {
 		return Props<IMessageToController>.Create(() => new AgentMessageHandlerActor(init), new ActorConfiguration { SupervisorStrategy = SupervisorStrategies.Resume });
 	}
 	
-	private readonly Guid agentGuid;
-	private readonly RpcConnectionToClient<IMessageToAgent> connection;
-	private readonly AgentRegistrationHandler agentRegistrationHandler;
+	private readonly RpcServerToClientConnection<IMessageToController, IMessageToAgent> connection;
 	private readonly AgentManager agentManager;
 	private readonly InstanceLogManager instanceLogManager;
 	private readonly EventLogManager eventLogManager;
 	
+	private Guid? registeredAgentGuid;
+	
 	private AgentMessageHandlerActor(Init init) {
-		this.agentGuid = init.AgentGuid;
 		this.connection = init.Connection;
-		this.agentRegistrationHandler = init.AgentRegistrationHandler;
 		this.agentManager = init.AgentManager;
 		this.instanceLogManager = init.InstanceLogManager;
 		this.eventLogManager = init.EventLogManager;
 		
-		ReceiveAsync<RegisterAgentMessage>(HandleRegisterAgent);
+		ReceiveAsyncAndReply<RegisterAgentMessage, ImmutableArray<ConfigureInstanceMessage>>(HandleRegisterAgent);
 		Receive<UnregisterAgentMessage>(HandleUnregisterAgent);
-		Receive<AgentIsAliveMessage>(HandleAgentIsAlive);
 		Receive<AdvertiseJavaRuntimesMessage>(HandleAdvertiseJavaRuntimes);
 		Receive<ReportAgentStatusMessage>(HandleReportAgentStatus);
 		Receive<ReportInstanceStatusMessage>(HandleReportInstanceStatus);
 		Receive<ReportInstancePlayerCountsMessage>(HandleReportInstancePlayerCounts);
 		Receive<ReportInstanceEventMessage>(HandleReportInstanceEvent);
 		Receive<InstanceOutputMessage>(HandleInstanceOutput);
-		Receive<ReplyMessage>(HandleReply);
 	}
 	
-	private async Task HandleRegisterAgent(RegisterAgentMessage message) {
-		if (agentGuid != message.AgentInfo.AgentGuid) {
-			await connection.Send(new RegisterAgentFailureMessage(RegisterAgentFailure.ConnectionAlreadyHasAnAgent));
-		}
-		else {
-			await agentRegistrationHandler.TryRegisterImpl(connection, message);
-		}
+	private Guid RequireAgentGuid() {
+		return registeredAgentGuid ?? throw new InvalidOperationException("Agent has not registered yet.");
+	}
+	
+	private Task<ImmutableArray<ConfigureInstanceMessage>> HandleRegisterAgent(RegisterAgentMessage message) {
+		registeredAgentGuid = message.AgentInfo.AgentGuid;
+		return agentManager.RegisterAgent(message.AgentInfo, connection);
 	}
 	
 	private void HandleUnregisterAgent(UnregisterAgentMessage message) {
+		Guid agentGuid = RequireAgentGuid();
 		agentManager.TellAgent(agentGuid, new AgentActor.UnregisterCommand(connection));
-		connection.Close();
-	}
-	
-	private void HandleAgentIsAlive(AgentIsAliveMessage message) {
-		agentManager.TellAgent(agentGuid, new AgentActor.NotifyIsAliveCommand());
+		agentManager.OnSessionClosed(connection.SessionId, agentGuid);
+		connection.CloseSession();
 	}
 	
 	private void HandleAdvertiseJavaRuntimes(AdvertiseJavaRuntimesMessage message) {
-		agentManager.TellAgent(agentGuid, new AgentActor.UpdateJavaRuntimesCommand(message.Runtimes));
+		agentManager.TellAgent(RequireAgentGuid(), new AgentActor.UpdateJavaRuntimesCommand(message.Runtimes));
 	}
 	
 	private void HandleReportAgentStatus(ReportAgentStatusMessage message) {
-		agentManager.TellAgent(agentGuid, new AgentActor.UpdateStatsCommand(message.RunningInstanceCount, message.RunningInstanceMemory));
+		agentManager.TellAgent(RequireAgentGuid(), new AgentActor.UpdateStatsCommand(message.RunningInstanceCount, message.RunningInstanceMemory));
 	}
 	
 	private void HandleReportInstanceStatus(ReportInstanceStatusMessage message) {
-		agentManager.TellAgent(agentGuid, new AgentActor.UpdateInstanceStatusCommand(message.InstanceGuid, message.InstanceStatus));
+		agentManager.TellAgent(RequireAgentGuid(), new AgentActor.UpdateInstanceStatusCommand(message.InstanceGuid, message.InstanceStatus));
 	}
 	
 	private void HandleReportInstancePlayerCounts(ReportInstancePlayerCountsMessage message) {
-		agentManager.TellAgent(agentGuid, new AgentActor.UpdateInstancePlayerCountsCommand(message.InstanceGuid, message.PlayerCounts));
+		agentManager.TellAgent(RequireAgentGuid(), new AgentActor.UpdateInstancePlayerCountsCommand(message.InstanceGuid, message.PlayerCounts));
 	}
 	
 	private void HandleReportInstanceEvent(ReportInstanceEventMessage message) {
-		message.Event.Accept(eventLogManager.CreateInstanceEventVisitor(message.EventGuid, message.UtcTime, agentGuid, message.InstanceGuid));
+		message.Event.Accept(eventLogManager.CreateInstanceEventVisitor(message.EventGuid, message.UtcTime, RequireAgentGuid(), message.InstanceGuid));
 	}
 	
 	private void HandleInstanceOutput(InstanceOutputMessage message) {
 		instanceLogManager.ReceiveLines(message.InstanceGuid, message.Lines);
 	}
-	
-	private void HandleReply(ReplyMessage message) {
-		connection.Receive(message);
-	}
 }

Controller/Phantom.Controller.Services/Rpc/AgentRegistrationHandler.cs

@@ -1,34 +0,0 @@
-using Phantom.Common.Messages.Agent;
-using Phantom.Common.Messages.Agent.ToController;
-using Phantom.Controller.Services.Agents;
-using Phantom.Controller.Services.Events;
-using Phantom.Controller.Services.Instances;
-using Phantom.Utils.Actor;
-using Phantom.Utils.Rpc.Runtime;
-
-namespace Phantom.Controller.Services.Rpc;
-
-sealed class AgentRegistrationHandler : IRegistrationHandler<IMessageToAgent, IMessageToController, RegisterAgentMessage> {
-	private readonly AgentManager agentManager;
-	private readonly InstanceLogManager instanceLogManager;
-	private readonly EventLogManager eventLogManager;
-	
-	public AgentRegistrationHandler(AgentManager agentManager, InstanceLogManager instanceLogManager, EventLogManager eventLogManager) {
-		this.agentManager = agentManager;
-		this.instanceLogManager = instanceLogManager;
-		this.eventLogManager = eventLogManager;
-	}
-	
-	async Task<Props<IMessageToController>?> IRegistrationHandler<IMessageToAgent, IMessageToController, RegisterAgentMessage>.TryRegister(RpcConnectionToClient<IMessageToAgent> connection, RegisterAgentMessage message) {
-		return await TryRegisterImpl(connection, message) ? CreateMessageHandlerActorProps(message.AgentInfo.AgentGuid, connection) : null;
-	}
-	
-	public Task<bool> TryRegisterImpl(RpcConnectionToClient<IMessageToAgent> connection, RegisterAgentMessage message) {
-		return agentManager.RegisterAgent(message.AuthToken, message.AgentInfo, connection);
-	}
-	
-	private Props<IMessageToController> CreateMessageHandlerActorProps(Guid agentGuid, RpcConnectionToClient<IMessageToAgent> connection) {
-		var init = new AgentMessageHandlerActor.Init(agentGuid, connection, this, agentManager, instanceLogManager, eventLogManager);
-		return AgentMessageHandlerActor.Factory(init);
-	}
-}

Controller/Phantom.Controller.Services/Rpc/RpcServerAgentHandshake.cs

@@ -1,34 +0,0 @@
-using Phantom.Common.Data;
-using Phantom.Common.Data.Agent;
-using Phantom.Common.Messages.Agent.Handshake;
-using Phantom.Utils.Logging;
-using Phantom.Utils.Rpc.New;
-using Serilog;
-
-namespace Phantom.Controller.Services.Rpc;
-
-public sealed class RpcServerAgentHandshake(AuthToken authToken) : RpcServerHandshake {
-	private static readonly ILogger Logger = PhantomLogger.Create<RpcServerAgentHandshake>();
-	
-	protected override async Task<bool> AcceptClient(string remoteAddress, Stream stream, CancellationToken cancellationToken) {
-		Memory<byte> buffer = new Memory<byte>(new byte[AuthToken.Length]);
-		await stream.ReadExactlyAsync(buffer, cancellationToken: cancellationToken);
-		
-		if (!authToken.FixedTimeEquals(buffer.Span)) {
-			Logger.Warning("Rejected client {}, invalid authorization token.", remoteAddress);
-			await Respond(remoteAddress, stream, new InvalidAuthToken(), cancellationToken);
-			return false;
-		}
-		
-		AgentInfo agentInfo = await Serialization.Deserialize<AgentInfo>(stream, cancellationToken);
-		return true;
-	}
-	
-	private async ValueTask Respond(string remoteAddress, Stream stream, IAgentHandshakeResult result, CancellationToken cancellationToken) {
-		try {
-			await Serialization.Serialize(result, stream, cancellationToken);
-		} catch (Exception e) {
-			Logger.Error(e, "Could not send handshake result to client {}.", remoteAddress);
-		}
-	}
-}

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

@@ -0,0 +1,33 @@
+using Akka.Actor;
+using Phantom.Common.Messages.Web;
+using Phantom.Controller.Minecraft;
+using Phantom.Controller.Services.Agents;
+using Phantom.Controller.Services.Events;
+using Phantom.Controller.Services.Instances;
+using Phantom.Controller.Services.Users;
+using Phantom.Controller.Services.Users.Sessions;
+using Phantom.Utils.Actor;
+using Phantom.Utils.Rpc.Message;
+using Phantom.Utils.Rpc.Runtime.Server;
+
+namespace Phantom.Controller.Services.Rpc;
+
+sealed class WebClientRegistrar(
+	IActorRefFactory actorSystem,
+	ControllerState controllerState,
+	InstanceLogManager instanceLogManager,
+	UserManager userManager,
+	RoleManager roleManager,
+	UserRoleManager userRoleManager,
+	UserLoginManager userLoginManager,
+	AuditLogManager auditLogManager,
+	AgentManager agentManager,
+	MinecraftVersions minecraftVersions,
+	EventLogManager eventLogManager
+) : 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);
+		return new IMessageReceiver<IMessageToController>.Actor(actorSystem.ActorOf(WebMessageHandlerActor.Factory(init), name));
+	}
+}

Controller/Phantom.Controller.Services/Rpc/WebMessageDataUpdateSenderActor.cs

@@ -10,13 +10,13 @@ using Phantom.Utils.Rpc.Runtime;
 namespace Phantom.Controller.Services.Rpc;
 
 sealed class WebMessageDataUpdateSenderActor : ReceiveActor<WebMessageDataUpdateSenderActor.ICommand> {
-	public readonly record struct Init(RpcConnectionToClient<IMessageToWeb> Connection, ControllerState ControllerState, InstanceLogManager InstanceLogManager);
+	public readonly record struct Init(RpcSendChannel<IMessageToWeb> Connection, ControllerState ControllerState, InstanceLogManager InstanceLogManager);
 	
 	public static Props<ICommand> Factory(Init init) {
 		return Props<ICommand>.Create(() => new WebMessageDataUpdateSenderActor(init), new ActorConfiguration { SupervisorStrategy = SupervisorStrategies.Resume });
 	}
 	
-	private readonly RpcConnectionToClient<IMessageToWeb> connection;
+	private readonly RpcSendChannel<IMessageToWeb> connection;
 	private readonly ControllerState controllerState;
 	private readonly InstanceLogManager instanceLogManager;
 	private readonly ActorRef<ICommand> selfCached;
@@ -70,18 +70,18 @@ sealed class WebMessageDataUpdateSenderActor : ReceiveActor<WebMessageDataUpdate
 	private sealed record RefreshUserSessionCommand(Guid UserGuid) : ICommand;
 	
 	private Task RefreshAgents(RefreshAgentsCommand command) {
-		return connection.Send(new RefreshAgentsMessage(command.Agents.Values.ToImmutableArray()));
+		return connection.SendMessage(new RefreshAgentsMessage(command.Agents.Values.ToImmutableArray())).AsTask();
 	}
 	
 	private Task RefreshInstances(RefreshInstancesCommand command) {
-		return connection.Send(new RefreshInstancesMessage(command.Instances.Values.ToImmutableArray()));
+		return connection.SendMessage(new RefreshInstancesMessage(command.Instances.Values.ToImmutableArray())).AsTask();
 	}
 	
 	private Task ReceiveInstanceLogs(ReceiveInstanceLogsCommand command) {
-		return connection.Send(new InstanceOutputMessage(command.InstanceGuid, command.Lines));
+		return connection.SendMessage(new InstanceOutputMessage(command.InstanceGuid, command.Lines)).AsTask();
 	}
 	
 	private Task RefreshUserSession(RefreshUserSessionCommand command) {
-		return connection.Send(new RefreshUserSessionMessage(command.UserGuid));
+		return connection.SendMessage(new RefreshUserSessionMessage(command.UserGuid)).AsTask();
 	}
 }

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

@@ -7,7 +7,6 @@ using Phantom.Common.Data.Web.AuditLog;
 using Phantom.Common.Data.Web.EventLog;
 using Phantom.Common.Data.Web.Instance;
 using Phantom.Common.Data.Web.Users;
-using Phantom.Common.Messages.Agent.BiDirectional;
 using Phantom.Common.Messages.Web;
 using Phantom.Common.Messages.Web.ToController;
 using Phantom.Controller.Minecraft;
@@ -17,14 +16,14 @@ using Phantom.Controller.Services.Instances;
 using Phantom.Controller.Services.Users;
 using Phantom.Controller.Services.Users.Sessions;
 using Phantom.Utils.Actor;
-using Phantom.Utils.Rpc.Runtime;
+using Phantom.Utils.Rpc.Runtime.Server;
 
 namespace Phantom.Controller.Services.Rpc;
 
 sealed class WebMessageHandlerActor : ReceiveActor<IMessageToController> {
 	public readonly record struct Init(
-		RpcConnectionToClient<IMessageToWeb> Connection,
-		WebRegistrationHandler WebRegistrationHandler,
+		RpcServerToClientConnection<IMessageToController, IMessageToWeb> Connection,
+		WebClientRegistrar WebClientRegistrar,
 		ControllerState ControllerState,
 		InstanceLogManager InstanceLogManager,
 		UserManager UserManager,
@@ -41,8 +40,7 @@ sealed class WebMessageHandlerActor : ReceiveActor<IMessageToController> {
 		return Props<IMessageToController>.Create(() => new WebMessageHandlerActor(init), new ActorConfiguration { SupervisorStrategy = SupervisorStrategies.Resume });
 	}
 	
-	private readonly RpcConnectionToClient<IMessageToWeb> connection;
-	private readonly WebRegistrationHandler webRegistrationHandler;
+	private readonly RpcServerToClientConnection<IMessageToController, IMessageToWeb> connection;
 	private readonly ControllerState controllerState;
 	private readonly UserManager userManager;
 	private readonly RoleManager roleManager;
@@ -55,7 +53,6 @@ sealed class WebMessageHandlerActor : ReceiveActor<IMessageToController> {
 	
 	private WebMessageHandlerActor(Init init) {
 		this.connection = init.Connection;
-		this.webRegistrationHandler = init.WebRegistrationHandler;
 		this.controllerState = init.ControllerState;
 		this.userManager = init.UserManager;
 		this.roleManager = init.RoleManager;
@@ -66,11 +63,10 @@ sealed class WebMessageHandlerActor : ReceiveActor<IMessageToController> {
 		this.minecraftVersions = init.MinecraftVersions;
 		this.eventLogManager = init.EventLogManager;
 		
-		var senderActorInit = new WebMessageDataUpdateSenderActor.Init(connection, controllerState, init.InstanceLogManager);
+		var senderActorInit = new WebMessageDataUpdateSenderActor.Init(connection.SendChannel, controllerState, init.InstanceLogManager);
 		Context.ActorOf(WebMessageDataUpdateSenderActor.Factory(senderActorInit), "DataUpdateSender");
 		
-		ReceiveAsync<RegisterWebMessage>(HandleRegisterWeb);
-		Receive<UnregisterWebMessage>(HandleUnregisterWeb);
+		ReceiveAsync<UnregisterWebMessage>(HandleUnregisterWeb);
 		ReceiveAndReplyLater<LogInMessage, Optional<LogInSuccess>>(HandleLogIn);
 		Receive<LogOutMessage>(HandleLogOut);
 		ReceiveAndReply<GetAuthenticatedUser, Optional<AuthenticatedUserInfo>>(GetAuthenticatedUser);
@@ -89,15 +85,10 @@ sealed class WebMessageHandlerActor : ReceiveActor<IMessageToController> {
 		ReceiveAndReply<GetAgentJavaRuntimesMessage, ImmutableDictionary<Guid, ImmutableArray<TaggedJavaRuntime>>>(HandleGetAgentJavaRuntimes);
 		ReceiveAndReplyLater<GetAuditLogMessage, Result<ImmutableArray<AuditLogItem>, UserActionFailure>>(HandleGetAuditLog);
 		ReceiveAndReplyLater<GetEventLogMessage, Result<ImmutableArray<EventLogItem>, UserActionFailure>>(HandleGetEventLog);
-		Receive<ReplyMessage>(HandleReply);
 	}
 	
-	private async Task HandleRegisterWeb(RegisterWebMessage message) {
-		await webRegistrationHandler.TryRegisterImpl(connection, message);
-	}
-	
-	private void HandleUnregisterWeb(UnregisterWebMessage message) {
-		connection.Close();
+	private Task HandleUnregisterWeb(UnregisterWebMessage message) {
+		return connection.CloseSession();
 	}
 	
 	private Task<Optional<LogInSuccess>> HandleLogIn(LogInMessage message) {
@@ -191,8 +182,4 @@ sealed class WebMessageHandlerActor : ReceiveActor<IMessageToController> {
 	private Task<Result<ImmutableArray<EventLogItem>, UserActionFailure>> HandleGetEventLog(GetEventLogMessage message) {
 		return eventLogManager.GetMostRecentItems(userLoginManager.GetLoggedInUser(message.AuthToken), message.Count);
 	}
-	
-	private void HandleReply(ReplyMessage message) {
-		connection.Receive(message);
-	}
 }

Controller/Phantom.Controller.Services/Rpc/WebRegistrationHandler.cs

@@ -1,68 +0,0 @@
-using Phantom.Common.Data;
-using Phantom.Common.Messages.Web;
-using Phantom.Common.Messages.Web.ToController;
-using Phantom.Common.Messages.Web.ToWeb;
-using Phantom.Controller.Minecraft;
-using Phantom.Controller.Services.Agents;
-using Phantom.Controller.Services.Events;
-using Phantom.Controller.Services.Instances;
-using Phantom.Controller.Services.Users;
-using Phantom.Controller.Services.Users.Sessions;
-using Phantom.Utils.Actor;
-using Phantom.Utils.Logging;
-using Phantom.Utils.Rpc.Runtime;
-using Serilog;
-
-namespace Phantom.Controller.Services.Rpc;
-
-sealed class WebRegistrationHandler : IRegistrationHandler<IMessageToWeb, IMessageToController, RegisterWebMessage> {
-	private static readonly ILogger Logger = PhantomLogger.Create<WebRegistrationHandler>();
-	
-	private readonly AuthToken webAuthToken;
-	private readonly ControllerState controllerState;
-	private readonly InstanceLogManager instanceLogManager;
-	private readonly UserManager userManager;
-	private readonly RoleManager roleManager;
-	private readonly UserRoleManager userRoleManager;
-	private readonly UserLoginManager userLoginManager;
-	private readonly AuditLogManager auditLogManager;
-	private readonly AgentManager agentManager;
-	private readonly MinecraftVersions minecraftVersions;
-	private readonly EventLogManager eventLogManager;
-	
-	public WebRegistrationHandler(AuthToken webAuthToken, ControllerState controllerState, InstanceLogManager instanceLogManager, UserManager userManager, RoleManager roleManager, UserRoleManager userRoleManager, UserLoginManager userLoginManager, AuditLogManager auditLogManager, AgentManager agentManager, MinecraftVersions minecraftVersions, EventLogManager eventLogManager) {
-		this.webAuthToken = webAuthToken;
-		this.controllerState = controllerState;
-		this.userManager = userManager;
-		this.roleManager = roleManager;
-		this.userRoleManager = userRoleManager;
-		this.userLoginManager = userLoginManager;
-		this.auditLogManager = auditLogManager;
-		this.agentManager = agentManager;
-		this.minecraftVersions = minecraftVersions;
-		this.eventLogManager = eventLogManager;
-		this.instanceLogManager = instanceLogManager;
-	}
-	
-	async Task<Props<IMessageToController>?> IRegistrationHandler<IMessageToWeb, IMessageToController, RegisterWebMessage>.TryRegister(RpcConnectionToClient<IMessageToWeb> connection, RegisterWebMessage message) {
-		return await TryRegisterImpl(connection, message) ? CreateMessageHandlerActorProps(connection) : null;
-	}
-	
-	public async Task<bool> TryRegisterImpl(RpcConnectionToClient<IMessageToWeb> connection, RegisterWebMessage message) {
-		if (webAuthToken.FixedTimeEquals(message.AuthToken)) {
-			Logger.Information("Web authorized successfully.");
-			await connection.Send(new RegisterWebResultMessage(true));
-			return true;
-		}
-		else {
-			Logger.Warning("Web failed to authorize, invalid token.");
-			await connection.Send(new RegisterWebResultMessage(false));
-			return false;
-		}
-	}
-	
-	private Props<IMessageToController> CreateMessageHandlerActorProps(RpcConnectionToClient<IMessageToWeb> connection) {
-		var init = new WebMessageHandlerActor.Init(connection, this, controllerState, instanceLogManager, userManager, roleManager, userRoleManager, userLoginManager, auditLogManager, agentManager, minecraftVersions, eventLogManager);
-		return WebMessageHandlerActor.Factory(init);
-	}
-}

Controller/Phantom.Controller/ConnectionKeyData.cs

@@ -1,5 +1,5 @@
-using Phantom.Common.Data;
-using Phantom.Utils.Rpc.New;
+using Phantom.Utils.Rpc;
+using Phantom.Utils.Rpc.Runtime.Tls;
 
 namespace Phantom.Controller;
 

Controller/Phantom.Controller/ConnectionKeyFiles.cs

@@ -3,7 +3,8 @@ using Phantom.Utils.Cryptography;
 using Phantom.Utils.IO;
 using Phantom.Utils.Logging;
 using Phantom.Utils.Monads;
-using Phantom.Utils.Rpc.New;
+using Phantom.Utils.Rpc;
+using Phantom.Utils.Rpc.Runtime.Tls;
 using Serilog;
 
 namespace Phantom.Controller;

Controller/Phantom.Controller/Program.cs

@@ -1,13 +1,16 @@
 using System.Reflection;
+using Phantom.Common.Messages.Agent;
+using Phantom.Common.Messages.Web;
 using Phantom.Controller;
 using Phantom.Controller.Database.Postgres;
 using Phantom.Controller.Services;
-using Phantom.Controller.Services.Rpc;
 using Phantom.Utils.IO;
 using Phantom.Utils.Logging;
-using Phantom.Utils.Rpc.New;
+using Phantom.Utils.Rpc.Runtime.Server;
 using Phantom.Utils.Runtime;
 using Phantom.Utils.Tasks;
+using RpcAgentServer = Phantom.Utils.Rpc.Runtime.Server.RpcServer<Phantom.Common.Messages.Agent.IMessageToController, Phantom.Common.Messages.Agent.IMessageToAgent>;
+using RpcWebServer = Phantom.Utils.Rpc.Runtime.Server.RpcServer<Phantom.Common.Messages.Web.IMessageToController, Phantom.Common.Messages.Web.IMessageToWeb>;
 
 var shutdownCancellationTokenSource = new CancellationTokenSource();
 var shutdownCancellationToken = shutdownCancellationTokenSource.Token;
@@ -54,12 +57,28 @@ try {
 	
 	var dbContextFactory = new ApplicationDbContextFactory(sqlConnectionString);
 	
-	using var controllerServices = new ControllerServices(dbContextFactory, agentKeyData.AuthToken, webKeyData.AuthToken, shutdownCancellationToken);
+	using var controllerServices = new ControllerServices(dbContextFactory, agentKeyData.AuthToken, shutdownCancellationToken);
 	await controllerServices.Initialize();
 	
+	var agentConnectionParameters = new RpcServerConnectionParameters(
+		EndPoint: agentRpcServerHost,
+		Certificate: agentKeyData.Certificate,
+		AuthToken: agentKeyData.AuthToken,
+		SendQueueCapacity: 100,
+		PingInterval: TimeSpan.FromSeconds(10)
+	);
+	
+	var webConnectionParameters = new RpcServerConnectionParameters(
+		EndPoint: webRpcServerHost,
+		Certificate: webKeyData.Certificate,
+		AuthToken: webKeyData.AuthToken,
+		SendQueueCapacity: 500,
+		PingInterval: TimeSpan.FromMinutes(1)
+	);
+	
 	LinkedTasks<bool> rpcServerTasks = new LinkedTasks<bool>([
-		new RpcServer("Agent", agentRpcServerHost, agentKeyData.Certificate, new RpcServerAgentHandshake(agentKeyData.AuthToken)).Run(shutdownCancellationToken),
-		// new RpcServer("Web", webRpcServerHost, webKeyData.Certificate).Run(shutdownCancellationToken),
+		new RpcAgentServer("Agent", agentConnectionParameters, AgentMessageRegistries.Definitions, controllerServices.AgentRegistrar).Run(shutdownCancellationToken),
+		new RpcWebServer("Web", webConnectionParameters, WebMessageRegistries.Definitions, controllerServices.WebRegistrar).Run(shutdownCancellationToken),
 	]);
 	
 	// If either RPC server crashes, stop the whole process.
@@ -72,11 +91,6 @@ try {
 	}
 	
 	return 0;
-	
-	// await Task.WhenAll(
-	// 	RpcServerRuntime.Launch(ConfigureRpc("Agent", agentRpcServerHost, agentRpcServerPort, agentKeyData), AgentMessageRegistries.Definitions, controllerServices.AgentRegistrationHandler, controllerServices.ActorSystem, shutdownCancellationToken),
-	// 	RpcServerRuntime.Launch(ConfigureRpc("Web", webRpcServerHost, webRpcServerPort, webKeyData), WebMessageRegistries.Definitions, controllerServices.WebRegistrationHandler, controllerServices.ActorSystem, shutdownCancellationToken)
-	// );
 } catch (OperationCanceledException) {
 	return 0;
 } catch (StopProcedureException) {

Controller/Phantom.Controller/Variables.cs

@@ -26,7 +26,7 @@ sealed record Variables(
 		
 		EndPoint webRpcServerHost = new IPEndPoint(
 			EnvironmentVariables.GetIpAddress("WEB_RPC_SERVER_HOST").WithDefault(IPAddress.Any),
-			EnvironmentVariables.GetPortNumber("WEB_RPC_SERVER_PORT").WithDefault(9401)
+			EnvironmentVariables.GetPortNumber("WEB_RPC_SERVER_PORT").WithDefault(9402)
 		);
 		
 		return new Variables(

Packages.props

@@ -23,7 +23,6 @@
   <ItemGroup>
     <PackageReference Update="BCrypt.Net-Next.StrongName" Version="4.0.3" />
     <PackageReference Update="MemoryPack"                 Version="1.10.0" />
-    <PackageReference Update="NetMQ"                      Version="4.0.1.13" />
   </ItemGroup>
   
   <ItemGroup>

PhantomPanel.sln

@@ -18,8 +18,6 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Phantom.Agent", "Agent\Phan
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Phantom.Agent.Minecraft", "Agent\Phantom.Agent.Minecraft\Phantom.Agent.Minecraft.csproj", "{9FE000D0-91AC-4CB4-8956-91CCC0270015}"
 EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Phantom.Agent.Rpc", "Agent\Phantom.Agent.Rpc\Phantom.Agent.Rpc.csproj", "{665C7B87-0165-48BC-B6A6-17A3812A70C9}"
-EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Phantom.Agent.Services", "Agent\Phantom.Agent.Services\Phantom.Agent.Services.csproj", "{AEE8B77E-AB07-423F-9981-8CD829ACB834}"
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Phantom.Common.Data", "Common\Phantom.Common.Data\Phantom.Common.Data.csproj", "{6C3DB1E5-F695-4D70-8F3A-78C2957274BE}"
@@ -76,10 +74,6 @@ Global
 		{9FE000D0-91AC-4CB4-8956-91CCC0270015}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{9FE000D0-91AC-4CB4-8956-91CCC0270015}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{9FE000D0-91AC-4CB4-8956-91CCC0270015}.Release|Any CPU.Build.0 = Release|Any CPU
-		{665C7B87-0165-48BC-B6A6-17A3812A70C9}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
-		{665C7B87-0165-48BC-B6A6-17A3812A70C9}.Debug|Any CPU.Build.0 = Debug|Any CPU
-		{665C7B87-0165-48BC-B6A6-17A3812A70C9}.Release|Any CPU.ActiveCfg = Release|Any CPU
-		{665C7B87-0165-48BC-B6A6-17A3812A70C9}.Release|Any CPU.Build.0 = Release|Any CPU
 		{AEE8B77E-AB07-423F-9981-8CD829ACB834}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
 		{AEE8B77E-AB07-423F-9981-8CD829ACB834}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{AEE8B77E-AB07-423F-9981-8CD829ACB834}.Release|Any CPU.ActiveCfg = Release|Any CPU
@@ -164,7 +158,6 @@ Global
 	GlobalSection(NestedProjects) = preSolution
 		{418BE1BF-9F63-4B46-B4E4-DF64C3B3DDA7} = {F5878792-64C8-4ECF-A075-66341FF97127}
 		{9FE000D0-91AC-4CB4-8956-91CCC0270015} = {F5878792-64C8-4ECF-A075-66341FF97127}
-		{665C7B87-0165-48BC-B6A6-17A3812A70C9} = {F5878792-64C8-4ECF-A075-66341FF97127}
 		{AEE8B77E-AB07-423F-9981-8CD829ACB834} = {F5878792-64C8-4ECF-A075-66341FF97127}
 		{6C3DB1E5-F695-4D70-8F3A-78C2957274BE} = {01CB1A81-8950-471C-BFDF-F135FDDB2C18}
 		{95B55357-F8F0-48C2-A1C2-5EA997651783} = {01CB1A81-8950-471C-BFDF-F135FDDB2C18}

Utils/Phantom.Utils.Logging/PhantomLogger.cs

@@ -31,25 +31,48 @@ public static class PhantomLogger {
 	}
 	
 	public static ILogger Create<T>() {
-		return Create(typeof(T).Name);
+		return Create(TypeName<T>());
 	}
 	
 	public static ILogger Create<T>(string name) {
-		return Create(typeof(T).Name, name);
+		return Create(ConcatNames(TypeName<T>(), name));
 	}
 	
 	public static ILogger Create<T>(string name1, string name2) {
-		return Create(typeof(T).Name, ConcatNames(name1, name2));
+		return Create(ConcatNames(TypeName<T>(), name1, name2));
 	}
 	
 	public static ILogger Create<T1, T2>() {
-		return Create(typeof(T1).Name, typeof(T2).Name);
+		return Create(ConcatNames(TypeName<T1>(), TypeName<T2>()));
 	}
 	
-	private static string ConcatNames(string name1, string name2) {
+	public static ILogger Create<T1, T2>(string name) {
+		return Create(ConcatNames(TypeName<T1>(), TypeName<T2>(), name));
+	}
+	
+	public static ILogger Create<T1, T2>(string name1, string name2) {
+		return Create(ConcatNames(TypeName<T1>(), TypeName<T2>(), ConcatNames(name1, name2)));
+	}
+	
+	private static string TypeName<T>() {
+		string typeName = typeof(T).Name;
+		int genericsStartIndex = typeName.IndexOf('`');
+		return genericsStartIndex > 0 ? typeName[..genericsStartIndex] : typeName;
+	}
+	
+	public static string ConcatNames(string name1, string name2) {
 		return name1 + ":" + name2;
 	}
 	
+	public static string ConcatNames(string name1, string name2, string name3) {
+		return ConcatNames(name1, ConcatNames(name2, name3));
+	}
+	
+	public static string ShortenGuid(Guid guid) {
+		var prefix = guid.ToString();
+		return prefix[..prefix.IndexOf('-')];
+	}
+	
 	public static void Dispose() {
 		Root.Dispose();
 		Base.Dispose();

Utils/Phantom.Utils.Rpc/AuthToken.cs

@@ -1,18 +1,12 @@
 using System.Collections.Immutable;
-using System.Diagnostics.CodeAnalysis;
 using System.Security.Cryptography;
-using MemoryPack;
 
-namespace Phantom.Common.Data;
+namespace Phantom.Utils.Rpc;
 
-[MemoryPackable(GenerateType.VersionTolerant)]
-[SuppressMessage("ReSharper", "MemberCanBePrivate.Global")]
-public sealed partial class AuthToken {
+public sealed class AuthToken {
 	public const int Length = 12;
 	
-	[MemoryPackOrder(0)]
-	[MemoryPackInclude]
-	public readonly ImmutableArray<byte> Bytes;
+	public ImmutableArray<byte> Bytes { get; }
 	
 	public AuthToken(ImmutableArray<byte> bytes) {
 		if (bytes.Length != Length) {
@@ -30,10 +24,6 @@ public sealed partial class AuthToken {
 		return CryptographicOperations.FixedTimeEquals(Bytes.AsSpan(), other);
 	}
 	
-	internal void WriteTo(Span<byte> span) {
-		Bytes.CopyTo(span);
-	}
-	
 	public static AuthToken Generate() {
 		return new AuthToken([..RandomNumberGenerator.GetBytes(Length)]);
 	}

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

@@ -0,0 +1,60 @@
+using Phantom.Utils.Rpc.Frame.Types;
+
+namespace Phantom.Utils.Rpc.Frame;
+
+interface IFrame {
+	private const byte TypePingId = 0;
+	private const byte TypePongId = 1;
+	private const byte TypeMessageId = 2;
+	private const byte TypeReplyId = 3;
+	private const byte TypeErrorId = 4;
+	
+	static readonly ReadOnlyMemory<byte> TypePing = new ([TypePingId]);
+	static readonly ReadOnlyMemory<byte> TypePong = new ([TypePongId]);
+	static readonly ReadOnlyMemory<byte> TypeMessage = new ([TypeMessageId]);
+	static readonly ReadOnlyMemory<byte> TypeReply = new ([TypeReplyId]);
+	static readonly ReadOnlyMemory<byte> TypeError = new ([TypeErrorId]);
+	
+	internal static async Task ReadFrom(Stream stream, IFrameReader reader, CancellationToken cancellationToken) {
+		byte[] oneByteBuffer = new byte[1];
+		
+		while (!cancellationToken.IsCancellationRequested) {
+			await stream.ReadExactlyAsync(oneByteBuffer, cancellationToken);
+			
+			switch (oneByteBuffer[0]) {
+				case TypePingId:
+					var pingTime = await PingFrame.Read(stream, cancellationToken);
+					await reader.OnPing(pingTime, cancellationToken);
+					break;
+				
+				case TypePongId:
+					var pongFrame = await PongFrame.Read(stream, cancellationToken);
+					reader.OnPongFrame(pongFrame);
+					break;
+				
+				case TypeMessageId:
+					var messageFrame = await MessageFrame.Read(stream, cancellationToken);
+					await reader.OnMessageFrame(messageFrame, cancellationToken);
+					break;
+				
+				case TypeReplyId:
+					var replyFrame = await ReplyFrame.Read(stream, cancellationToken);
+					reader.OnReplyFrame(replyFrame);
+					break;
+				
+				case TypeErrorId:
+					var errorFrame = await ErrorFrame.Read(stream, cancellationToken);
+					reader.OnErrorFrame(errorFrame);
+					break;
+				
+				default:
+					reader.OnUnknownFrameStart(oneByteBuffer[0]);
+					break;
+			}
+		}
+	}
+	
+	ReadOnlyMemory<byte> FrameType { get; }
+	
+	Task Write(Stream stream, CancellationToken cancellationToken = default);
+}

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

@@ -0,0 +1,12 @@
+using Phantom.Utils.Rpc.Frame.Types;
+
+namespace Phantom.Utils.Rpc.Frame;
+
+interface IFrameReader {
+	ValueTask OnPing(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);
+}

Utils/Phantom.Utils.Rpc/Frame/Types/ErrorFrame.cs

@@ -0,0 +1,18 @@
+using Phantom.Utils.Rpc.Runtime;
+
+namespace Phantom.Utils.Rpc.Frame.Types;
+
+sealed record ErrorFrame(uint ReplyingToMessageId, RpcError Error) : IFrame {
+	public ReadOnlyMemory<byte> FrameType => IFrame.TypeError;
+	
+	public async Task Write(Stream stream, CancellationToken cancellationToken) {
+		await Serialization.WriteUnsignedInt(ReplyingToMessageId, stream, cancellationToken);
+		await Serialization.WriteByte((byte) Error, stream, cancellationToken);
+	}
+	
+	public static async Task<ErrorFrame> Read(Stream stream, CancellationToken cancellationToken) {
+		var replyingToMessageId = await Serialization.ReadUnsignedInt(stream, cancellationToken);
+		var messageError = (RpcError) await Serialization.ReadByte(stream, cancellationToken);
+		return new ErrorFrame(replyingToMessageId, messageError);
+	}
+}

Utils/Phantom.Utils.Rpc/Frame/Types/MessageFrame.cs

@@ -0,0 +1,39 @@
+using Phantom.Utils.Rpc.Runtime;
+
+namespace Phantom.Utils.Rpc.Frame.Types;
+
+sealed record MessageFrame(uint MessageId, ushort RegistryCode, ReadOnlyMemory<byte> SerializedMessage) : IFrame {
+	public const int MaxMessageBytes = 1024 * 1024 * 8;
+	
+	public ReadOnlyMemory<byte> FrameType => IFrame.TypeMessage;
+	
+	public async Task Write(Stream stream, CancellationToken cancellationToken) {
+		int messageLength = SerializedMessage.Length;
+		CheckMessageLength(messageLength);
+		
+		await Serialization.WriteUnsignedInt(MessageId, stream, cancellationToken);
+		await Serialization.WriteUnsignedShort(RegistryCode, stream, cancellationToken);
+		await Serialization.WriteSignedInt(messageLength, stream, cancellationToken);
+		await stream.WriteAsync(SerializedMessage, cancellationToken);
+	}
+	
+	public static async Task<MessageFrame> Read(Stream stream, CancellationToken cancellationToken) {
+		var messageId = await Serialization.ReadUnsignedInt(stream, cancellationToken);
+		var registryCode = await Serialization.ReadUnsignedShort(stream, cancellationToken);
+		var essageLength = await Serialization.ReadSignedInt(stream, cancellationToken);
+		CheckMessageLength(essageLength);
+		var serializedMessage = await Serialization.ReadBytes(essageLength, stream, cancellationToken);
+		
+		return new MessageFrame(messageId, registryCode, serializedMessage);
+	}
+	
+	private static void CheckMessageLength(int messageLength) {
+		if (messageLength < 0) {
+			throw new RpcErrorException("Message length is negative.", RpcError.InvalidData);
+		}
+		
+		if (messageLength > MaxMessageBytes) {
+			throw new RpcErrorException("Message is too large: " + messageLength + " > " + MaxMessageBytes + " bytes", RpcError.MessageTooLarge);
+		}
+	}
+}

Utils/Phantom.Utils.Rpc/Frame/Types/PingFrame.cs

@@ -0,0 +1,15 @@
+namespace Phantom.Utils.Rpc.Frame.Types;
+
+sealed record PingFrame : IFrame {
+	public static PingFrame Instance { get; } = new ();
+	
+	public ReadOnlyMemory<byte> FrameType => IFrame.TypePing;
+	
+	public async Task Write(Stream stream, CancellationToken cancellationToken) {
+		await Serialization.WriteSignedLong(DateTimeOffset.UtcNow.ToUnixTimeMilliseconds(), stream, cancellationToken);
+	}
+	
+	public static async Task<DateTimeOffset> Read(Stream stream, CancellationToken cancellationToken) {
+		return DateTimeOffset.FromUnixTimeMilliseconds(await Serialization.ReadSignedLong(stream, cancellationToken));
+	}
+}

Utils/Phantom.Utils.Rpc/Frame/Types/PongFrame.cs

@@ -0,0 +1,13 @@
+namespace Phantom.Utils.Rpc.Frame.Types;
+
+sealed record PongFrame(DateTimeOffset PingTime) : IFrame {
+	public ReadOnlyMemory<byte> FrameType => IFrame.TypePong;
+	
+	public async Task Write(Stream stream, CancellationToken cancellationToken) {
+		await Serialization.WriteSignedLong(PingTime.ToUnixTimeMilliseconds(), stream, cancellationToken);
+	}
+	
+	public static async Task<PongFrame> Read(Stream stream, CancellationToken cancellationToken) {
+		return new PongFrame(DateTimeOffset.FromUnixTimeMilliseconds(await Serialization.ReadSignedLong(stream, cancellationToken)));
+	}
+}

Utils/Phantom.Utils.Rpc/Frame/Types/ReplyFrame.cs

@@ -0,0 +1,37 @@
+using Phantom.Utils.Rpc.Runtime;
+
+namespace Phantom.Utils.Rpc.Frame.Types;
+
+sealed record ReplyFrame(uint ReplyingToMessageId, ReadOnlyMemory<byte> SerializedReply) : IFrame {
+	public const int MaxReplyBytes = 1024 * 1024 * 32;
+	
+	public ReadOnlyMemory<byte> FrameType => IFrame.TypeReply;
+	
+	public async Task Write(Stream stream, CancellationToken cancellationToken) {
+		int replyLength = SerializedReply.Length;
+		CheckReplyLength(replyLength);
+		
+		await Serialization.WriteUnsignedInt(ReplyingToMessageId, stream, cancellationToken);
+		await Serialization.WriteSignedInt(replyLength, stream, cancellationToken);
+		await stream.WriteAsync(SerializedReply, cancellationToken);
+	}
+	
+	public static async Task<ReplyFrame> Read(Stream stream, CancellationToken cancellationToken) {
+		var replyingToMessageId = await Serialization.ReadUnsignedInt(stream, cancellationToken);
+		var replyLength = await Serialization.ReadSignedInt(stream, cancellationToken);
+		CheckReplyLength(replyLength);
+		var reply = await Serialization.ReadBytes(replyLength, stream, cancellationToken);
+		
+		return new ReplyFrame(replyingToMessageId, reply);
+	}
+	
+	private static void CheckReplyLength(int replyLength) {
+		if (replyLength < 0) {
+			throw new RpcErrorException("Reply length is negative.", RpcError.InvalidData);
+		}
+		
+		if (replyLength > MaxReplyBytes) {
+			throw new RpcErrorException("Reply is too large: " + replyLength + " > " + MaxReplyBytes + " bytes", RpcError.MessageTooLarge);
+		}
+	}
+}

Utils/Phantom.Utils.Rpc/IRpcListener.cs

@@ -0,0 +1,5 @@
+namespace Phantom.Utils.Rpc;
+
+public interface IRpcListener {
+	
+}

Utils/Phantom.Utils.Rpc/IRpcReplySender.cs

@@ -0,0 +1,8 @@
+using Phantom.Utils.Rpc.Runtime;
+
+namespace Phantom.Utils.Rpc;
+
+interface IRpcReplySender {
+	ValueTask SendReply<TReply>(uint replyingToMessageId, TReply reply, CancellationToken cancellationToken);
+	ValueTask SendError(uint replyingToMessageId, RpcError error, CancellationToken cancellationToken);
+}

Utils/Phantom.Utils.Rpc/Message/IMessageDefinitions.cs

@@ -1,6 +1,6 @@
 namespace Phantom.Utils.Rpc.Message;
 
-public interface IMessageDefinitions<TClientMessage, TServerMessage, TReplyMessage> : IReplyMessageFactory<TReplyMessage> where TReplyMessage : TClientMessage, TServerMessage {
-	MessageRegistry<TClientMessage> ToClient { get; }
-	MessageRegistry<TServerMessage> ToServer { get; }
+public interface IMessageDefinitions<TClientToServerMessage, TServerToClientMessage> {
+	MessageRegistry<TServerToClientMessage> ToClient { get; }
+	MessageRegistry<TClientToServerMessage> ToServer { get; }
 }

Utils/Phantom.Utils.Rpc/Message/IMessageReceiver.cs

@@ -0,0 +1,21 @@
+using Phantom.Utils.Actor;
+
+namespace Phantom.Utils.Rpc.Message;
+
+public interface IMessageReceiver<TMessageBase> {
+	void OnPing();
+	void OnMessage(TMessageBase message);
+	Task<TReply> OnMessage<TMessage, TReply>(TMessage message, CancellationToken cancellationToken = default) where TMessage : TMessageBase, ICanReply<TReply>;
+	
+	class Actor(ActorRef<TMessageBase> actor) : IMessageReceiver<TMessageBase> {
+		public virtual void OnPing() {}
+		
+		public void OnMessage(TMessageBase message) {
+			actor.Tell(message);
+		}
+		
+		public Task<TReply> OnMessage<TMessage, TReply>(TMessage message, CancellationToken cancellationToken = default) where TMessage : TMessageBase, ICanReply<TReply> {
+			return actor.Request(message, cancellationToken);
+		}
+	}
+}

Utils/Phantom.Utils.Rpc/Message/IReply.cs

@@ -1,6 +0,0 @@
-namespace Phantom.Utils.Rpc.Message;
-
-public interface IReply {
-	uint SequenceId { get; }
-	byte[] SerializedReply { get; }
-}

Utils/Phantom.Utils.Rpc/Message/IReplyMessageFactory.cs

@@ -1,5 +0,0 @@
-namespace Phantom.Utils.Rpc.Message;
-
-public interface IReplyMessageFactory<TReplyMessage> {
-	TReplyMessage CreateReplyMessage(uint sequenceId, byte[] serializedReply);
-}

Utils/Phantom.Utils.Rpc/Message/IReplySender.cs

@@ -1,5 +0,0 @@
-namespace Phantom.Utils.Rpc.Message;
-
-interface IReplySender {
-	Task SendReply(uint sequenceId, byte[] serializedReply);
-}

Utils/Phantom.Utils.Rpc/Message/MessageHandler.cs

@@ -1,35 +0,0 @@
-using Phantom.Utils.Actor;
-using Phantom.Utils.Logging;
-using Serilog;
-
-namespace Phantom.Utils.Rpc.Message;
-
-sealed class MessageHandler<TMessageBase> {
-	private readonly ILogger logger;
-	private readonly ActorRef<TMessageBase> handlerActor;
-	private readonly IReplySender replySender;
-	
-	public MessageHandler(string loggerName, ActorRef<TMessageBase> handlerActor, IReplySender replySender) {
-		this.logger = PhantomLogger.Create("MessageHandler", loggerName);
-		this.handlerActor = handlerActor;
-		this.replySender = replySender;
-	}
-	
-	public void Tell(TMessageBase message) {
-		handlerActor.Tell(message);
-	}
-	
-	public Task TellAndReply<TMessage, TReply>(TMessage message, uint sequenceId) where TMessage : ICanReply<TReply> {
-		return handlerActor.Request(message).ContinueWith(task => {
-			if (task.IsCompletedSuccessfully) {
-				return replySender.SendReply(sequenceId, MessageSerializer.Serialize(task.Result));
-			}
-			
-			if (task.IsFaulted) {
-				logger.Error(task.Exception, "Failed to handle message {Type}.", message.GetType().Name);
-			}
-			
-			return task;
-		}, TaskScheduler.Default);
-	}
-}

Utils/Phantom.Utils.Rpc/Message/MessageRegistry.cs

@@ -1,26 +1,19 @@
-using System.Buffers;
-using System.Diagnostics.CodeAnalysis;
+using System.Diagnostics.CodeAnalysis;
 using Phantom.Utils.Actor;
+using Phantom.Utils.Rpc.Frame.Types;
+using Phantom.Utils.Rpc.Runtime;
 using Serilog;
-using Serilog.Events;
 
 namespace Phantom.Utils.Rpc.Message;
 
-public sealed class MessageRegistry<TMessageBase> {
-	private const int DefaultBufferSize = 512;
-	
-	private readonly ILogger logger;
+public sealed class MessageRegistry<TMessageBase>(ILogger logger) {
 	private readonly Dictionary<Type, ushort> typeToCodeMapping = new ();
 	private readonly Dictionary<ushort, Type> codeToTypeMapping = new ();
-	private readonly Dictionary<ushort, Action<ReadOnlyMemory<byte>, ushort, MessageHandler<TMessageBase>>> codeToHandlerMapping = new ();
-	
-	public MessageRegistry(ILogger logger) {
-		this.logger = logger;
-	}
+	private readonly Dictionary<ushort, Func<uint, ReadOnlyMemory<byte>, RpcMessageHandler<TMessageBase>, CancellationToken, Task>> codeToHandlerMapping = new ();
 	
 	public void Add<TMessage>(ushort code) where TMessage : TMessageBase {
 		if (HasReplyType(typeof(TMessage))) {
-			throw new ArgumentException("This overload is for messages without a reply");
+			throw new ArgumentException("This overload is for messages without a reply.");
 		}
 		
 		AddTypeCodeMapping<TMessage>(code);
@@ -44,140 +37,68 @@ public sealed class MessageRegistry<TMessageBase> {
 		return messageType.GetInterfaces().Any(type => type.FullName is {} name && name.StartsWith(replyInterfaceName, StringComparison.Ordinal));
 	}
 	
-	internal bool TryGetType(ReadOnlyMemory<byte> data, [NotNullWhen(true)] out Type? type) {
-		try {
-			var code = MessageSerializer.ReadCode(ref data);
-			return codeToTypeMapping.TryGetValue(code, out type);
-		} catch (Exception) {
-			type = null;
-			return false;
-		}
+	internal bool TryGetType(MessageFrame frame, [NotNullWhen(true)] out Type? type) {
+		return codeToTypeMapping.TryGetValue(frame.RegistryCode, out type);
 	}
 	
-	public ReadOnlySpan<byte> Write<TMessage>(TMessage message) where TMessage : TMessageBase {
-		if (!GetMessageCode<TMessage>(out var code)) {
-			return default;
-		}
-		
-		var buffer = new ArrayBufferWriter<byte>(DefaultBufferSize);
-		
-		try {
-			MessageSerializer.WriteCode(buffer, code);
-			MessageSerializer.Serialize(buffer, message);
-			
-			CheckWrittenBufferLength<TMessage>(buffer);
-			return buffer.WrittenSpan;
-		} catch (Exception e) {
-			LogWriteFailure<TMessage>(e);
-			return default;
-		}
-	}
-	
-	public ReadOnlySpan<byte> Write<TMessage, TReply>(uint sequenceId, TMessage message) where TMessage : TMessageBase, ICanReply<TReply> {
-		if (!GetMessageCode<TMessage>(out var code)) {
-			return default;
-		}
-		
-		var buffer = new ArrayBufferWriter<byte>(DefaultBufferSize);
-		
-		try {
-			MessageSerializer.WriteCode(buffer, code);
-			MessageSerializer.WriteSequenceId(buffer, sequenceId);
-			MessageSerializer.Serialize(buffer, message);
-			
-			CheckWrittenBufferLength<TMessage>(buffer);
-			return buffer.WrittenSpan;
-		} catch (Exception e) {
-			LogWriteFailure<TMessage>(e);
-			return default;
-		}
-	}
-	
-	private bool GetMessageCode<TMessage>(out ushort code) where TMessage : TMessageBase {
-		if (typeToCodeMapping.TryGetValue(typeof(TMessage), out code)) {
-			return true;
+	internal MessageFrame CreateFrame<TMessage>(uint messageId, TMessage message) where TMessage : TMessageBase {
+		if (typeToCodeMapping.TryGetValue(typeof(TMessage), out ushort code)) {
+			return new MessageFrame(messageId, code, Serialization.Serialize(message));
 		}
 		else {
-			logger.Error("Unknown message type {Type}.", typeof(TMessage));
-			return false;
+			throw new ArgumentException("Unknown message type: " + typeof(TMessage));
 		}
 	}
 	
-	private void CheckWrittenBufferLength<TMessage>(ArrayBufferWriter<byte> buffer) where TMessage : TMessageBase {
-		if (buffer.WrittenCount > DefaultBufferSize && logger.IsEnabled(LogEventLevel.Verbose)) {
-			logger.Verbose("Serializing {Type} exceeded default buffer size: {WrittenSize} B > {DefaultBufferSize} B", typeof(TMessage).Name, buffer.WrittenCount, DefaultBufferSize);
-		}
-	}
-	
-	private void LogWriteFailure<TMessage>(Exception e) where TMessage : TMessageBase {
-		logger.Error(e, "Failed to serialize message {Type}.", typeof(TMessage).Name);
-	}
-	
-	internal bool Read<TMessage>(ReadOnlyMemory<byte> data, out TMessage message) where TMessage : TMessageBase {
-		if (ReadTypeCode(ref data, out ushort code) && codeToTypeMapping.TryGetValue(code, out var expectedType) && expectedType == typeof(TMessage) && ReadMessage(data, out message)) {
-			return true;
+	internal async Task Handle(MessageFrame frame, RpcMessageHandler<TMessageBase> handler, CancellationToken cancellationToken) {
+		uint messageId = frame.MessageId;
+		
+		if (codeToHandlerMapping.TryGetValue(frame.RegistryCode, out var action)) {
+			await action(messageId, frame.SerializedMessage, handler, cancellationToken);
 		}
 		else {
-			message = default!;
-			return false;
+			logger.Error("Unknown message code {Code} for message {MessageId}.", frame.RegistryCode, messageId);
+			await handler.SendError(messageId, RpcError.UnknownMessageRegistryCode, cancellationToken);
 		}
 	}
 	
-	internal void Handle(ReadOnlyMemory<byte> data, MessageHandler<TMessageBase> handler) {
-		if (!ReadTypeCode(ref data, out var code)) {
+	private async Task DeserializationHandler<TMessage>(uint messageId, ReadOnlyMemory<byte> serializedMessage, RpcMessageHandler<TMessageBase> handler, CancellationToken cancellationToken) where TMessage : TMessageBase {
+		TMessage message;
+		try {
+			message = Serialization.Deserialize<TMessage>(serializedMessage);
+		} catch (Exception e) {
+			logger.Error(e, "Could not deserialize message {MessageId} ({MessageType}).", messageId, typeof(TMessage).Name);
+			await handler.SendError(messageId, RpcError.MessageDeserializationError, cancellationToken);
 			return;
 		}
 		
-		if (!codeToHandlerMapping.TryGetValue(code, out var handle)) {
-			logger.Error("Unknown message code {Code}.", code);
+		handler.Receiver.OnMessage(message);
+	}
+	
+	private async Task DeserializationHandler<TMessage, TReply>(uint messageId, ReadOnlyMemory<byte> serializedMessage, RpcMessageHandler<TMessageBase> handler, CancellationToken cancellationToken) where TMessage : TMessageBase, ICanReply<TReply> {
+		TMessage message;
+		try {
+			message = Serialization.Deserialize<TMessage>(serializedMessage);
+		} catch (Exception e) {
+			logger.Error(e, "Could not deserialize message {MessageId} ({MessageType}).", messageId, typeof(TMessage).Name);
+			await handler.SendError(messageId, RpcError.MessageDeserializationError, cancellationToken);
 			return;
 		}
 		
-		handle(data, code, handler);
-	}
-	
-	private bool ReadTypeCode(ref ReadOnlyMemory<byte> data, out ushort code) {
+		TReply reply;
 		try {
-			code = MessageSerializer.ReadCode(ref data);
-			return true;
+			reply = await handler.Receiver.OnMessage<TMessage, TReply>(message, cancellationToken);
 		} catch (Exception e) {
-			code = default;
-			logger.Error(e, "Failed to deserialize message code.");
-			return false;
+			logger.Error(e, "Could not handle message {MessageId} ({MessageType}).", messageId, typeof(TMessage).Name);
+			await handler.SendError(messageId, RpcError.MessageHandlingError, cancellationToken);
+			return;
 		}
-	}
-	
-	private bool ReadSequenceId<TMessage, TReply>(ref ReadOnlyMemory<byte> data, out uint sequenceId) where TMessage : TMessageBase, ICanReply<TReply> {
+		
 		try {
-			sequenceId = MessageSerializer.ReadSequenceId(ref data);
-			return true;
+			await handler.SendReply(messageId, reply, cancellationToken);
 		} catch (Exception e) {
-			sequenceId = default;
-			logger.Error(e, "Failed to deserialize sequence ID of message {Type}.", typeof(TMessage).Name);
-			return false;
-		}
-	}
-	
-	private bool ReadMessage<TMessage>(ReadOnlyMemory<byte> data, out TMessage message) where TMessage : TMessageBase {
-		try {
-			message = MessageSerializer.Deserialize<TMessage>(data);
-			return true;
-		} catch (Exception e) {
-			message = default!;
-			logger.Error(e, "Failed to deserialize message {Type}.", typeof(TMessage).Name);
-			return false;
-		}
-	}
-	
-	private void DeserializationHandler<TMessage>(ReadOnlyMemory<byte> data, ushort code, MessageHandler<TMessageBase> handler) where TMessage : TMessageBase {
-		if (ReadMessage<TMessage>(data, out var message)) {
-			handler.Tell(message);
-		}
-	}
-	
-	private void DeserializationHandler<TMessage, TReply>(ReadOnlyMemory<byte> data, ushort code, MessageHandler<TMessageBase> handler) where TMessage : TMessageBase, ICanReply<TReply> {
-		if (ReadSequenceId<TMessage, TReply>(ref data, out var sequenceId) && ReadMessage<TMessage>(data, out var message)) {
-			handler.TellAndReply<TMessage, TReply>(message, sequenceId);
+			logger.Error(e, "Could not reply to message {MessageId} ({MessageType}).", messageId, typeof(TMessage).Name);
+			await handler.SendError(messageId, RpcError.MessageHandlingError, cancellationToken);
 		}
 	}
 }

Utils/Phantom.Utils.Rpc/Message/MessageReplyTracker.cs

@@ -1,5 +1,6 @@
 using System.Collections.Concurrent;
 using Phantom.Utils.Logging;
+using Phantom.Utils.Rpc.Runtime;
 using Phantom.Utils.Tasks;
 using Serilog;
 
@@ -7,55 +8,57 @@ namespace Phantom.Utils.Rpc.Message;
 
 sealed class MessageReplyTracker {
 	private readonly ILogger logger;
-	private readonly ConcurrentDictionary<uint, TaskCompletionSource<byte[]>> replyTasks = new (4, 16);
-	
-	private uint lastSequenceId;
+	private readonly ConcurrentDictionary<uint, TaskCompletionSource<ReadOnlyMemory<byte>>> replyTasks = new (concurrencyLevel: 2, capacity: 16);
 	
 	internal MessageReplyTracker(string loggerName) {
 		this.logger = PhantomLogger.Create<MessageReplyTracker>(loggerName);
 	}
 	
-	public uint RegisterReply() {
-		var sequenceId = Interlocked.Increment(ref lastSequenceId);
-		replyTasks[sequenceId] = AsyncTasks.CreateCompletionSource<byte[]>();
-		return sequenceId;
+	public void RegisterReply(uint messageId) {
+		replyTasks[messageId] = AsyncTasks.CreateCompletionSource<ReadOnlyMemory<byte>>();
 	}
 	
-	public async Task<TReply> WaitForReply<TReply>(uint sequenceId, TimeSpan waitForReplyTime, CancellationToken cancellationToken) {
-		if (!replyTasks.TryGetValue(sequenceId, out var completionSource)) {
-			logger.Warning("No reply callback for id {SequenceId}.", sequenceId);
-			throw new ArgumentException("No reply callback for id: " + sequenceId, nameof(sequenceId));
+	public async Task<TReply> WaitForReply<TReply>(uint messageId, TimeSpan waitForReplyTime, CancellationToken cancellationToken) {
+		if (!replyTasks.TryGetValue(messageId, out var completionSource)) {
+			logger.Warning("No reply callback for id {MessageId}.", messageId);
+			throw new ArgumentException("No reply callback for id: " + messageId, nameof(messageId));
 		}
 		
 		try {
-			byte[] replyBytes = await completionSource.Task.WaitAsync(waitForReplyTime, cancellationToken);
-			return MessageSerializer.Deserialize<TReply>(replyBytes);
+			ReadOnlyMemory<byte> serializedReply = await completionSource.Task.WaitAsync(waitForReplyTime, cancellationToken);
+			return Serialization.Deserialize<TReply>(serializedReply);
 		} catch (TimeoutException) {
-			logger.Debug("Timed out waiting for reply with id {SequenceId}.", sequenceId);
+			logger.Debug("Timed out waiting for reply with id {MessageId}.", messageId);
 			throw;
 		} catch (OperationCanceledException) {
-			logger.Debug("Cancelled waiting for reply with id {SequenceId}.", sequenceId);
+			logger.Debug("Cancelled waiting for reply with id {MessageId}.", messageId);
 			throw;
 		} catch (Exception e) {
-			logger.Warning(e, "Error processing reply with id {SequenceId}.", sequenceId);
+			logger.Warning(e, "Error processing reply with id {MessageId}.", messageId);
 			throw;
 		} finally {
-			ForgetReply(sequenceId);
+			ForgetReply(messageId);
 		}
 	}
 	
-	public void ForgetReply(uint sequenceId) {
-		if (replyTasks.TryRemove(sequenceId, out var task)) {
+	public void ForgetReply(uint messageId) {
+		if (replyTasks.TryRemove(messageId, out var task)) {
 			task.SetCanceled();
 		}
 	}
 	
-	public void ReceiveReply(uint sequenceId, byte[] serializedReply) {
-		if (replyTasks.TryRemove(sequenceId, out var task)) {
+	public void FailReply(uint messageId, RpcErrorException e) {
+		if (replyTasks.TryRemove(messageId, out var task)) {
+			task.SetException(e);
+		}
+	}
+	
+	public void ReceiveReply(uint messageId, ReadOnlyMemory<byte> serializedReply) {
+		if (replyTasks.TryRemove(messageId, out var task)) {
 			task.SetResult(serializedReply);
 		}
 		else {
-			logger.Warning("Received a reply with id {SequenceId} but no registered callback.", sequenceId);
+			logger.Warning("Received a reply with id {MessageId} but no registered callback.", messageId);
 		}
 	}
 }

Utils/Phantom.Utils.Rpc/Message/MessageSerializer.cs

@@ -1,45 +0,0 @@
-using System.Buffers;
-using System.Buffers.Binary;
-using MemoryPack;
-
-namespace Phantom.Utils.Rpc.Message;
-
-static class MessageSerializer {
-	private static readonly MemoryPackSerializerOptions SerializerOptions = MemoryPackSerializerOptions.Utf8;
-	
-	public static byte[] Serialize<T>(T message) {
-		return MemoryPackSerializer.Serialize(message, SerializerOptions);
-	}
-	
-	public static void Serialize<T>(IBufferWriter<byte> destination, T message) {
-		MemoryPackSerializer.Serialize(typeof(T), destination, message, SerializerOptions);
-	}
-	
-	public static T Deserialize<T>(ReadOnlyMemory<byte> memory) {
-		return MemoryPackSerializer.Deserialize<T>(memory.Span) ?? throw new NullReferenceException();
-	}
-	
-	public static void WriteCode(IBufferWriter<byte> destination, ushort value) {
-		Span<byte> buffer = stackalloc byte[2];
-		BinaryPrimitives.WriteUInt16LittleEndian(buffer, value);
-		destination.Write(buffer);
-	}
-	
-	public static ushort ReadCode(ref ReadOnlyMemory<byte> memory) {
-		ushort value = BinaryPrimitives.ReadUInt16LittleEndian(memory.Span);
-		memory = memory[2..];
-		return value;
-	}
-	
-	public static void WriteSequenceId(IBufferWriter<byte> destination, uint sequenceId) {
-		Span<byte> buffer = stackalloc byte[4];
-		BinaryPrimitives.WriteUInt32LittleEndian(buffer, sequenceId);
-		destination.Write(buffer);
-	}
-	
-	public static uint ReadSequenceId(ref ReadOnlyMemory<byte> memory) {
-		uint value = BinaryPrimitives.ReadUInt32LittleEndian(memory.Span);
-		memory = memory[4..];
-		return value;
-	}
-}

Utils/Phantom.Utils.Rpc/Message/ReplySender.cs

@@ -1,17 +0,0 @@
-using Phantom.Utils.Rpc.Runtime;
-
-namespace Phantom.Utils.Rpc.Message;
-
-sealed class ReplySender<TMessageBase, TReplyMessage> : IReplySender where TReplyMessage : TMessageBase {
-	private readonly RpcConnection<TMessageBase> connection;
-	private readonly IReplyMessageFactory<TReplyMessage> replyMessageFactory;
-	
-	public ReplySender(RpcConnection<TMessageBase> connection, IReplyMessageFactory<TReplyMessage> replyMessageFactory) {
-		this.connection = connection;
-		this.replyMessageFactory = replyMessageFactory;
-	}
-	
-	public Task SendReply(uint sequenceId, byte[] serializedReply) {
-		return connection.Send(replyMessageFactory.CreateReplyMessage(sequenceId, serializedReply));
-	}
-}

Utils/Phantom.Utils.Rpc/New/RpcClient.cs

@@ -1,100 +0,0 @@
-using System.Net.Security;
-using System.Net.Sockets;
-using System.Security.Authentication;
-using System.Security.Cryptography.X509Certificates;
-using Phantom.Utils.Logging;
-using Serilog;
-
-namespace Phantom.Utils.Rpc.New;
-
-public sealed class RpcClient<TClientToServerMessage, TServerToClientMessage>(string loggerName, string host, ushort port, string distinguishedName, RpcCertificateThumbprint certificateThumbprint, RpcClientHandshake handshake) {
-	private readonly ILogger logger = PhantomLogger.Create<RpcClient<TClientToServerMessage, TServerToClientMessage>>(loggerName);
-	
-	private bool loggedCertificateValidationError = false;
-	
-	private bool ValidateServerCertificate(object sender, X509Certificate? certificate, X509Chain? chain, SslPolicyErrors sslPolicyErrors) {
-		if (certificate == null || sslPolicyErrors.HasFlag(SslPolicyErrors.RemoteCertificateNotAvailable)) {
-			logger.Error("Could not establish a secure connection, server did not provide a certificate.");
-		}
-		else if (sslPolicyErrors.HasFlag(SslPolicyErrors.RemoteCertificateNameMismatch)) {
-			logger.Error("Could not establish a secure connection, server certificate has the wrong name: {Name}", certificate.Subject);
-		}
-		else if (!certificateThumbprint.Check(certificate)) {
-			logger.Error("Could not establish a secure connection, server certificate does not match.");
-		}
-		else if (TlsSupport.CheckAlgorithm((X509Certificate2) certificate) is {} error) {
-			logger.Error("Could not establish a secure connection, server certificate rejected because it uses {ActualAlgorithmName} instead of {ExpectedAlgorithmName}.", error.ActualAlgorithmName, error.ExpectedAlgorithmName);
-		}
-		else if ((sslPolicyErrors & ~SslPolicyErrors.RemoteCertificateChainErrors) != SslPolicyErrors.None) {
-			logger.Error("Could not establish a secure connection, server certificate validation failed.");
-		}
-		else {
-			return true;
-		}
-		
-		loggedCertificateValidationError = true;
-		return false;
-	}
-	
-	public async Task<RpcClientConnection<TClientToServerMessage>?> Connect(CancellationToken shutdownToken) {
-		SslClientAuthenticationOptions sslOptions = new () {
-			AllowRenegotiation = false,
-			AllowTlsResume = true,
-			CertificateRevocationCheckMode = X509RevocationMode.NoCheck,
-			EnabledSslProtocols = TlsSupport.SupportedProtocols,
-			EncryptionPolicy = EncryptionPolicy.RequireEncryption,
-			RemoteCertificateValidationCallback = ValidateServerCertificate,
-			TargetHost = distinguishedName,
-		};
-		
-		try {
-			using var clientSocket = new Socket(SocketType.Stream, ProtocolType.Tcp);
-			
-			logger.Information("Connecting to {Host}:{Port}...", host, port);
-			
-			try {
-				await clientSocket.ConnectAsync(host, port, shutdownToken);
-			} catch (Exception e) {
-				logger.Error(e, "Could not connect.");
-				return null;
-			}
-			
-			await using var stream = new SslStream(new NetworkStream(clientSocket, ownsSocket: false), leaveInnerStreamOpen: false);
-			
-			try {
-				loggedCertificateValidationError = false;
-				await stream.AuthenticateAsClientAsync(sslOptions, shutdownToken);
-			} catch (AuthenticationException e) {
-				if (!loggedCertificateValidationError) {
-					logger.Error(e, "Could not establish a secure connection.");
-				}
-				
-				return null;
-			}
-			
-			logger.Information("Established a secure connection.");
-			
-			try {
-				await handshake.AcceptServer(stream, shutdownToken);
-			} catch (EndOfStreamException) {
-				logger.Warning("Could not perform application handshake, connection lost.");
-				return null;
-			} catch (Exception e) {
-				logger.Warning(e, "Could not perform application handshake.");
-				return null;
-			}
-			// await stream.WriteAsync(new byte[] { 1, 2, 3 }, shutdownToken);
-			
-			byte[] buffer = new byte[1024];
-			int readBytes;
-			while ((readBytes = await stream.ReadAsync(buffer, shutdownToken)) > 0) {}
-		} catch (Exception e) {
-			logger.Error(e, "Client crashed with uncaught exception.");
-			return null;
-		} finally {
-			logger.Information("Client stopped.");
-		}
-		
-		return true;
-	}
-}

Utils/Phantom.Utils.Rpc/New/RpcClientConnection.cs

@@ -1,30 +0,0 @@
-using System.Threading.Channels;
-using Phantom.Utils.Logging;
-using Serilog;
-
-namespace Phantom.Utils.Rpc.New;
-
-public class RpcClientConnection<TClientToServerMessage>(string loggerName, CancellationToken shutdownCancellationToken) : IAsyncDisposable {
-	private readonly ILogger logger = PhantomLogger.Create<RpcClientConnection<TClientToServerMessage>>(loggerName);
-	
-	private readonly Channel<TClientToServerMessage> sendQueue = Channel.CreateBounded<TClientToServerMessage>(new BoundedChannelOptions(500) {
-		AllowSynchronousContinuations = false,
-		FullMode = BoundedChannelFullMode.Wait,
-		SingleReader = true,
-		SingleWriter = false,
-	});
-	
-	public async Task WaitFor() {
-		
-	}
-	
-	public async Task Send(TClientToServerMessage message, CancellationToken cancellationToken) {
-		if (!sendQueue.Writer.TryWrite(message)) {
-			await sendQueue.Writer.WriteAsync(message, cancellationToken);
-		}
-	}
-	
-	public async ValueTask DisposeAsync() {
-		// TODO release managed resources here
-	}
-}

Utils/Phantom.Utils.Rpc/New/RpcClientHandshake.cs

@@ -1,5 +0,0 @@
-namespace Phantom.Utils.Rpc.New;
-
-public abstract class RpcClientHandshake {
-	protected internal abstract Task<bool> AcceptServer(Stream stream, CancellationToken cancellationToken);
-}

Utils/Phantom.Utils.Rpc/New/RpcHandshakeResult.cs

@@ -1,6 +0,0 @@
-namespace Phantom.Utils.Rpc.New;
-
-public enum RpcHandshakeResult : byte {
-	UnknownError = 0,
-	InvalidFormat = 1,
-}

Utils/Phantom.Utils.Rpc/New/RpcServer.cs

@@ -1,122 +0,0 @@
-using System.Net;
-using System.Net.Security;
-using System.Net.Sockets;
-using System.Security.Cryptography.X509Certificates;
-using Phantom.Utils.Logging;
-using Serilog;
-
-namespace Phantom.Utils.Rpc.New;
-
-public sealed class RpcServer(string loggerName, EndPoint endPoint, RpcServerCertificate certificate, RpcServerHandshake handshake) {
-	private readonly ILogger logger = PhantomLogger.Create<RpcServer>(loggerName);
-	
-	private readonly List<Client> clients = [];
-	
-	public async Task<bool> Run(CancellationToken shutdownToken) {
-		SslServerAuthenticationOptions sslOptions = new () {
-			AllowRenegotiation = false,
-			AllowTlsResume = true,
-			CertificateRevocationCheckMode = X509RevocationMode.NoCheck,
-			ClientCertificateRequired = false,
-			EnabledSslProtocols = TlsSupport.SupportedProtocols,
-			EncryptionPolicy = EncryptionPolicy.RequireEncryption,
-			ServerCertificate = certificate.Certificate,
-		};
-		
-		try {
-			using var serverSocket = new Socket(endPoint.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
-			
-			try {
-				serverSocket.Bind(endPoint);
-				serverSocket.Listen(5);
-			} catch (Exception e) {
-				logger.Error(e, "Could not bind to {EndPoint}.", endPoint);
-				return false;
-			}
-			
-			try {
-				logger.Information("Server listening on {EndPoint}.", endPoint);
-				
-				while (!shutdownToken.IsCancellationRequested) {
-					Socket clientSocket = await serverSocket.AcceptAsync(shutdownToken);
-					clients.Add(new Client(logger, clientSocket, sslOptions, handshake, shutdownToken));
-					clients.RemoveAll(static client => client.Task.IsCompleted);
-				}
-			} finally {
-				await Stop(serverSocket);
-			}
-		} catch (Exception e) {
-			logger.Error(e, "Server crashed with uncaught exception.");
-			return false;
-		}
-		
-		return true;
-	}
-	
-	private async Task Stop(Socket serverSocket) {
-		try {
-			serverSocket.Close();
-		} catch (Exception e) {
-			logger.Error(e, "Server socket failed to close.");
-			return;
-		}
-		
-		logger.Information("Server socket closed, waiting for client sockets to close.");
-		
-		try {
-			await Task.WhenAll(clients.Select(static client => client.Task));
-		} catch (Exception) {
-			// Ignore exceptions when shutting down.
-		}
-		
-		logger.Information("Server stopped.");
-	}
-	
-	private sealed class Client {
-		public Task Task { get; }
-		
-		private readonly ILogger logger;
-		private readonly Socket socket;
-		private readonly SslServerAuthenticationOptions sslOptions;
-		private readonly RpcServerHandshake handshake;
-		private readonly CancellationToken shutdownToken;
-		
-		public Client(ILogger logger, Socket socket, SslServerAuthenticationOptions sslOptions, RpcServerHandshake handshake, CancellationToken shutdownToken) {
-			this.logger = logger;
-			this.socket = socket;
-			this.sslOptions = sslOptions;
-			this.handshake = handshake;
-			this.shutdownToken = shutdownToken;
-			this.Task = Run();
-		}
-		
-		private async Task Run() {
-			try {
-				await using var stream = new SslStream(new NetworkStream(socket, ownsSocket: false), leaveInnerStreamOpen: false);
-				
-				try {
-					await stream.AuthenticateAsServerAsync(sslOptions, shutdownToken);
-				} catch (Exception e) {
-					logger.Error(e, "Could not establish a secure connection.");
-					return;
-				}
-				
-				try {
-					await handshake.AcceptClient(socket.RemoteEndPoint?.ToString() ?? "<unknown address>", stream, shutdownToken);
-				} catch (EndOfStreamException) {
-					logger.Warning("Could not perform application handshake, connection lost.");
-					return;
-				} catch (Exception e) {
-					logger.Warning(e, "Could not perform application handshake.");
-					return;
-				}
-				
-				byte[] buffer = new byte[1024];
-				int readBytes;
-				while ((readBytes = await stream.ReadAsync(buffer, shutdownToken)) > 0) {}
-			} finally {
-				socket.Close();
-			}
-		}
-	}
-}

Utils/Phantom.Utils.Rpc/New/RpcServerHandshake.cs

@@ -1,5 +0,0 @@
-namespace Phantom.Utils.Rpc.New;
-
-public abstract class RpcServerHandshake {
-	protected internal abstract Task<bool> AcceptClient(string remoteAddress, Stream stream, CancellationToken cancellationToken);
-}

Utils/Phantom.Utils.Rpc/New/Serialization.cs

@@ -1,15 +0,0 @@
-using MemoryPack;
-
-namespace Phantom.Utils.Rpc.New;
-
-public static class Serialization {
-	private static readonly MemoryPackSerializerOptions SerializerOptions = MemoryPackSerializerOptions.Utf8;
-	
-	public static ValueTask Serialize<T>(T value, Stream stream, CancellationToken cancellationToken) {
-		return MemoryPackSerializer.SerializeAsync(stream, value, SerializerOptions, cancellationToken);
-	}
-	
-	public static async ValueTask<T> Deserialize<T>(Stream stream, CancellationToken cancellationToken) {
-		return (await MemoryPackSerializer.DeserializeAsync<T>(stream, SerializerOptions, cancellationToken))!;
-	}
-}

Utils/Phantom.Utils.Rpc/Phantom.Utils.Rpc.csproj

@@ -7,7 +7,6 @@
   
   <ItemGroup>
     <PackageReference Include="MemoryPack" />
-    <PackageReference Include="NetMQ" />
     <PackageReference Include="Serilog" />
   </ItemGroup>
   

Utils/Phantom.Utils.Rpc/RpcConfiguration.cs

@@ -1,8 +0,0 @@
-using NetMQ;
-
-namespace Phantom.Utils.Rpc;
-
-public sealed record RpcConfiguration(string ServiceName, string Host, ushort Port, NetMQCertificate ServerCertificate) {
-	internal string LoggerName => "Rpc:" + ServiceName;
-	internal string TcpUrl => "tcp://" + Host + ":" + Port;
-}

Utils/Phantom.Utils.Rpc/RpcExtensions.cs

@@ -1,32 +0,0 @@
-using NetMQ;
-using NetMQ.Sockets;
-
-namespace Phantom.Utils.Rpc;
-
-static class RpcExtensions {
-	public static ReadOnlyMemory<byte> Receive(this ClientSocket socket, CancellationToken cancellationToken) {
-		var msg = new Msg();
-		msg.InitEmpty();
-		
-		try {
-			socket.Receive(ref msg, cancellationToken);
-			return msg.SliceAsMemory();
-		} finally {
-			// Only releases references, so the returned ReadOnlyMemory is safe.
-			msg.Close();
-		}
-	}
-	
-	public static (uint, ReadOnlyMemory<byte>) Receive(this ServerSocket socket, CancellationToken cancellationToken) {
-		var msg = new Msg();
-		msg.InitEmpty();
-		
-		try {
-			socket.Receive(ref msg, cancellationToken);
-			return (msg.RoutingId, msg.SliceAsMemory());
-		} finally {
-			// Only releases references, so the returned ReadOnlyMemory is safe.
-			msg.Close();
-		}
-	}
-}

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

@@ -0,0 +1,62 @@
+using Phantom.Utils.Logging;
+using Phantom.Utils.Rpc.Message;
+using Serilog;
+
+namespace Phantom.Utils.Rpc.Runtime.Client;
+
+public sealed class RpcClient<TClientToServerMessage, TServerToClientMessage> : IDisposable {
+	public static async Task<RpcClient<TClientToServerMessage, TServerToClientMessage>?> Connect(string loggerName, RpcClientConnectionParameters connectionParameters, IMessageDefinitions<TClientToServerMessage, TServerToClientMessage> messageDefinitions, CancellationToken cancellationToken) {
+		RpcClientToServerConnector connector = new RpcClientToServerConnector(loggerName, connectionParameters);
+		RpcClientToServerConnector.Connection? connection = await connector.EstablishNewConnection(cancellationToken);
+		return connection == null ? null : new RpcClient<TClientToServerMessage, TServerToClientMessage>(loggerName, connectionParameters, messageDefinitions, connector, connection);
+	}
+	
+	private readonly string loggerName;
+	private readonly ILogger logger;
+	private readonly MessageRegistry<TServerToClientMessage> serverToClientMessageRegistry;
+	private readonly RpcClientToServerConnection connection;
+	
+	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.connection = new RpcClientToServerConnection(loggerName, connector, connection);
+		this.SendChannel = new RpcSendChannel<TClientToServerMessage>(loggerName, connectionParameters.Common, this.connection, messageDefinitions.ToServer);
+	}
+	
+	public async Task Listen(IMessageReceiver<TServerToClientMessage> receiver) {
+		var messageHandler = new RpcMessageHandler<TServerToClientMessage>(receiver, SendChannel);
+		var frameReader = new RpcFrameReader<TClientToServerMessage, TServerToClientMessage>(loggerName, serverToClientMessageRegistry, messageHandler, SendChannel);
+		try {
+			await connection.ReadConnection(frameReader, CancellationToken.None);
+		} catch (OperationCanceledException) {
+			// Ignore.
+		}
+	}
+	
+	public async Task Shutdown() {
+		logger.Information("Shutting down client...");
+		
+		try {
+			await SendChannel.Close();
+		} catch (Exception e) {
+			logger.Error(e, "Caught exception while closing send channel.");
+		}
+		
+		try {
+			connection.Close();
+		} catch (Exception e) {
+			logger.Error(e, "Caught exception while closing connection.");
+		}
+		
+		logger.Information("Client shut down.");
+	}
+	
+	public void Dispose() {
+		connection.Dispose();
+		SendChannel.Dispose();
+	}
+}

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

@@ -0,0 +1,15 @@
+using Phantom.Utils.Rpc.Runtime.Tls;
+
+namespace Phantom.Utils.Rpc.Runtime.Client;
+
+public readonly record struct RpcClientConnectionParameters(
+	string Host,
+	ushort Port,
+	string DistinguishedName,
+	RpcCertificateThumbprint CertificateThumbprint,
+	AuthToken AuthToken,
+	ushort SendQueueCapacity,
+	TimeSpan PingInterval
+) {
+	internal RpcCommonConnectionParameters Common => new (SendQueueCapacity, PingInterval);
+}

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

@@ -0,0 +1,86 @@
+using Phantom.Utils.Logging;
+using Phantom.Utils.Rpc.Frame;
+using Serilog;
+
+namespace Phantom.Utils.Rpc.Runtime.Client;
+
+sealed class RpcClientToServerConnection(string loggerName, RpcClientToServerConnector connector, RpcClientToServerConnector.Connection initialConnection) : IRpcConnectionProvider, IDisposable {
+	private readonly ILogger logger = PhantomLogger.Create<RpcClientToServerConnection>(loggerName);
+	
+	private readonly SemaphoreSlim semaphore = new (1);
+	private RpcClientToServerConnector.Connection currentConnection = initialConnection;
+	
+	private readonly CancellationTokenSource newConnectionCancellationTokenSource = new ();
+	
+	public async Task<Stream> GetStream() {
+		return (await GetConnection()).Stream;
+	}
+	
+	private async Task<RpcClientToServerConnector.Connection> GetConnection() {
+		CancellationToken cancellationToken = newConnectionCancellationTokenSource.Token;
+		
+		await semaphore.WaitAsync(cancellationToken);
+		try {
+			if (!currentConnection.Socket.Connected) {
+				currentConnection = await connector.EstablishNewConnectionWithRetry(cancellationToken);
+			}
+			
+			return currentConnection;
+		} finally {
+			semaphore.Release();
+		}
+	}
+	
+	public async Task ReadConnection(IFrameReader frameReader, CancellationToken cancellationToken) {
+		RpcClientToServerConnector.Connection? connection = null;
+		
+		try {
+			while (true) {
+				connection?.Dispose();
+				connection = null;
+				
+				try {
+					connection = await GetConnection();
+				} catch (OperationCanceledException) {
+					throw;
+				} catch (Exception e) {
+					logger.Warning(e, "Could not obtain a new connection.");
+					continue;
+				}
+				
+				try {
+					await IFrame.ReadFrom(connection.Stream, frameReader, cancellationToken);
+				} catch (OperationCanceledException) {
+					throw;
+				} catch (EndOfStreamException) {
+					logger.Warning("Socket was closed.");
+				} catch (Exception e) {
+					logger.Error(e, "Closing socket due to an exception while reading it.");
+					
+					try {
+						await connection.Shutdown();
+					} catch (Exception e2) {
+						logger.Error(e2, "Caught exception closing the socket.");
+					}
+				}
+			}
+		} finally {
+			if (connection != null) {
+				try {
+					await connection.Disconnect(); // TODO what happens if already disconnected?
+				} finally {
+					connection.Dispose();
+				}
+			}
+		}
+	}
+	
+	public void Close() {
+		newConnectionCancellationTokenSource.Cancel();
+	}
+	
+	public void Dispose() {
+		semaphore.Dispose();
+		newConnectionCancellationTokenSource.Dispose();
+	}
+}

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

@@ -0,0 +1,190 @@
+using System.Net.Security;
+using System.Net.Sockets;
+using System.Security.Authentication;
+using System.Security.Cryptography.X509Certificates;
+using Phantom.Utils.Collections;
+using Phantom.Utils.Logging;
+using Phantom.Utils.Rpc.Runtime.Tls;
+using Serilog;
+
+namespace Phantom.Utils.Rpc.Runtime.Client;
+
+internal sealed class RpcClientToServerConnector {
+	private static readonly TimeSpan InitialRetryDelay = TimeSpan.FromMilliseconds(100);
+	private static readonly TimeSpan MaximumRetryDelay = TimeSpan.FromSeconds(30);
+	private static readonly TimeSpan DisconnectTimeout = TimeSpan.FromSeconds(10);
+	
+	private readonly ILogger logger;
+	private readonly Guid sessionId;
+	private readonly RpcClientConnectionParameters parameters;
+	private readonly SslClientAuthenticationOptions sslOptions;
+	
+	private bool loggedCertificateValidationError = false;
+	
+	public RpcClientToServerConnector(string loggerName, RpcClientConnectionParameters parameters) {
+		this.logger = PhantomLogger.Create<RpcClientToServerConnector>(loggerName);
+		this.sessionId = Guid.NewGuid();
+		this.parameters = parameters;
+		
+		this.sslOptions = new SslClientAuthenticationOptions {
+			AllowRenegotiation = false,
+			AllowTlsResume = true,
+			CertificateRevocationCheckMode = X509RevocationMode.NoCheck,
+			EnabledSslProtocols = TlsSupport.SupportedProtocols,
+			EncryptionPolicy = EncryptionPolicy.RequireEncryption,
+			RemoteCertificateValidationCallback = ValidateServerCertificate,
+			TargetHost = parameters.DistinguishedName,
+		};
+	}
+	
+	internal async Task<Connection> EstablishNewConnectionWithRetry(CancellationToken cancellationToken) {
+		TimeSpan nextAttemptDelay = InitialRetryDelay;
+		
+		while (true) {
+			Connection? newConnection;
+			try {
+				newConnection = await EstablishNewConnection(cancellationToken);
+			} catch (Exception e) {
+				logger.Error(e, "Caught unhandled exception while connecting.");
+				newConnection = null;
+			}
+			
+			if (newConnection != null) {
+				return newConnection;
+			}
+			
+			logger.Warning("Failed to connect to server, trying again in {}.", nextAttemptDelay.TotalSeconds.ToString("F1"));
+			
+			await Task.Delay(nextAttemptDelay, cancellationToken);
+			nextAttemptDelay = Comparables.Min(nextAttemptDelay.Multiply(1.5), MaximumRetryDelay);
+		}
+	}
+	
+	internal async Task<Connection?> EstablishNewConnection(CancellationToken cancellationToken) {
+		logger.Information("Connecting to {Host}:{Port}...", parameters.Host, parameters.Port);
+		
+		Socket clientSocket = new Socket(SocketType.Stream, ProtocolType.Tcp);
+		try {
+			await clientSocket.ConnectAsync(parameters.Host, parameters.Port, cancellationToken);
+		} catch (Exception e) {
+			logger.Error(e, "Could not connect.");
+			throw;
+		}
+		
+		SslStream? stream;
+		try {
+			stream = new SslStream(new NetworkStream(clientSocket, ownsSocket: false), leaveInnerStreamOpen: false);
+			
+			if (await FinalizeConnection(stream, cancellationToken)) {
+				logger.Information("Connected to {Host}:{Port}.", parameters.Host, parameters.Port);
+				return new Connection(clientSocket, stream);
+			}
+		} catch (Exception e) {
+			logger.Error(e, "Caught unhandled exception.");
+			stream = null;
+		}
+		
+		try {
+			await DisconnectSocket(clientSocket, stream);
+		} finally {
+			clientSocket.Close();
+		}
+		
+		return null;
+	}
+	
+	private async Task<bool> FinalizeConnection(SslStream stream, CancellationToken cancellationToken) {
+		try {
+			loggedCertificateValidationError = false;
+			await stream.AuthenticateAsClientAsync(sslOptions, cancellationToken);
+		} catch (AuthenticationException e) {
+			if (!loggedCertificateValidationError) {
+				logger.Error(e, "Could not establish a secure connection.");
+			}
+			
+			return false;
+		}
+		
+		logger.Information("Established a secure connection.");
+		
+		try {
+			if (!await PerformApplicationHandshake(stream, cancellationToken)) {
+				return false;
+			}
+		} catch (EndOfStreamException) {
+			logger.Warning("Could not perform application handshake, connection lost.");
+		} catch (Exception e) {
+			logger.Warning(e, "Could not perform application handshake.");
+		}
+		
+		return true;
+	}
+	
+	private async Task<bool> PerformApplicationHandshake(Stream stream, CancellationToken cancellationToken) {
+		await Serialization.WriteAuthToken(parameters.AuthToken, stream, cancellationToken);
+		await Serialization.WriteGuid(sessionId, stream, cancellationToken);
+		
+		var result = (RpcHandshakeResult) await Serialization.ReadByte(stream, cancellationToken);
+		switch (result) {
+			case RpcHandshakeResult.Success:
+				return true;
+			
+			case RpcHandshakeResult.InvalidAuthToken:
+				logger.Error("Server rejected authorization token.");
+				return false;
+			
+			default:
+				logger.Error("Server rejected client due to unknown error: {ErrorId}", result);
+				return false;
+		}
+	}
+	
+	private bool ValidateServerCertificate(object sender, X509Certificate? certificate, X509Chain? chain, SslPolicyErrors sslPolicyErrors) {
+		if (certificate == null || sslPolicyErrors.HasFlag(SslPolicyErrors.RemoteCertificateNotAvailable)) {
+			logger.Error("Could not establish a secure connection, server did not provide a certificate.");
+		}
+		else if (sslPolicyErrors.HasFlag(SslPolicyErrors.RemoteCertificateNameMismatch)) {
+			logger.Error("Could not establish a secure connection, server certificate has the wrong name: {Name}", certificate.Subject);
+		}
+		else if (!parameters.CertificateThumbprint.Check(certificate)) {
+			logger.Error("Could not establish a secure connection, server certificate does not match.");
+		}
+		else if (TlsSupport.CheckAlgorithm((X509Certificate2) certificate) is {} error) {
+			logger.Error("Could not establish a secure connection, server certificate rejected because it uses {ActualAlgorithmName} instead of {ExpectedAlgorithmName}.", error.ActualAlgorithmName, error.ExpectedAlgorithmName);
+		}
+		else if ((sslPolicyErrors & ~SslPolicyErrors.RemoteCertificateChainErrors) != SslPolicyErrors.None) {
+			logger.Error("Could not establish a secure connection, server certificate validation failed.");
+		}
+		else {
+			return true;
+		}
+		
+		loggedCertificateValidationError = true;
+		return false;
+	}
+	
+	private static async Task DisconnectSocket(Socket socket, Stream? stream) {
+		if (stream != null) {
+			await stream.DisposeAsync();
+		}
+		
+		using CancellationTokenSource timeoutTokenSource = new CancellationTokenSource(DisconnectTimeout);
+		await socket.DisconnectAsync(reuseSocket: false, timeoutTokenSource.Token);
+	}
+	
+	internal sealed record Connection(Socket Socket, Stream Stream) : IDisposable {
+		public async Task Disconnect() {
+			await DisconnectSocket(Socket, Stream);
+		}
+		
+		public async ValueTask Shutdown() {
+			await Stream.DisposeAsync();
+			Socket.Shutdown(SocketShutdown.Both);
+		}
+		
+		public void Dispose() {
+			Stream.Dispose();
+			Socket.Close();
+		}
+	}
+}

Utils/Phantom.Utils.Rpc/Runtime/IRegistrationHandler.cs

@@ -1,7 +0,0 @@
-using Phantom.Utils.Actor;
-
-namespace Phantom.Utils.Rpc.Runtime;
-
-public interface IRegistrationHandler<TClientMessage, TServerMessage, TRegistrationMessage> where TRegistrationMessage : TServerMessage {
-	Task<Props<TServerMessage>?> TryRegister(RpcConnectionToClient<TClientMessage> connection, TRegistrationMessage message);
-}

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

@@ -0,0 +1,5 @@
+namespace Phantom.Utils.Rpc.Runtime;
+
+interface IRpcConnectionProvider {
+	Task<Stream> GetStream();
+}

Utils/Phantom.Utils.Rpc/Runtime/RpcClientConnectionClosedEventArgs.cs

@@ -1,9 +0,0 @@
-namespace Phantom.Utils.Rpc.Runtime;
-
-sealed class RpcClientConnectionClosedEventArgs : EventArgs {
-	internal uint RoutingId { get; }
-	
-	internal RpcClientConnectionClosedEventArgs(uint routingId) {
-		RoutingId = routingId;
-	}
-}

Utils/Phantom.Utils.Rpc/Runtime/RpcClientRuntime.cs

@@ -1,72 +0,0 @@
-using NetMQ.Sockets;
-using Phantom.Utils.Actor;
-using Phantom.Utils.Rpc.Message;
-using Phantom.Utils.Rpc.Sockets;
-using Serilog;
-using Serilog.Events;
-
-namespace Phantom.Utils.Rpc.Runtime;
-
-public abstract class RpcClientRuntime<TClientMessage, TServerMessage, TReplyMessage> : RpcRuntime<ClientSocket> where TReplyMessage : TClientMessage, TServerMessage {
-	private readonly RpcConnectionToServer<TServerMessage> connection;
-	private readonly IMessageDefinitions<TClientMessage, TServerMessage, TReplyMessage> messageDefinitions;
-	private readonly ActorRef<TClientMessage> handlerActor;
-	
-	private readonly SemaphoreSlim disconnectSemaphore;
-	private readonly CancellationToken receiveCancellationToken;
-	
-	protected RpcClientRuntime(RpcClientSocket<TClientMessage, TServerMessage, TReplyMessage> socket, ActorRef<TClientMessage> handlerActor, SemaphoreSlim disconnectSemaphore, CancellationToken receiveCancellationToken) : base(socket) {
-		this.connection = socket.Connection;
-		this.messageDefinitions = socket.MessageDefinitions;
-		this.handlerActor = handlerActor;
-		this.disconnectSemaphore = disconnectSemaphore;
-		this.receiveCancellationToken = receiveCancellationToken;
-	}
-	
-	private protected sealed override Task Run(ClientSocket socket) {
-		return RunWithConnection(socket, connection);
-	}
-	
-	protected virtual async Task RunWithConnection(ClientSocket socket, RpcConnectionToServer<TServerMessage> connection) {
-		var replySender = new ReplySender<TServerMessage, TReplyMessage>(connection, messageDefinitions);
-		var messageHandler = new MessageHandler<TClientMessage>(LoggerName, handlerActor, replySender);
-		
-		try {
-			while (!receiveCancellationToken.IsCancellationRequested) {
-				var data = socket.Receive(receiveCancellationToken);
-				
-				LogMessageType(RuntimeLogger, data);
-				
-				if (data.Length > 0) {
-					messageDefinitions.ToClient.Handle(data, messageHandler);
-				}
-			}
-		} catch (OperationCanceledException) {
-			// Ignore.
-		} finally {
-			await handlerActor.Stop();
-			RuntimeLogger.Debug("ZeroMQ client stopped receiving messages.");
-			
-			await disconnectSemaphore.WaitAsync(CancellationToken.None);
-		}
-	}
-	
-	private protected sealed override async Task Disconnect(ClientSocket socket) {
-		await SendDisconnectMessage(socket, RuntimeLogger);
-	}
-	
-	protected abstract Task SendDisconnectMessage(ClientSocket socket, ILogger logger);
-	
-	private void LogMessageType(ILogger logger, ReadOnlyMemory<byte> data) {
-		if (!logger.IsEnabled(LogEventLevel.Verbose)) {
-			return;
-		}
-		
-		if (data.Length > 0 && messageDefinitions.ToClient.TryGetType(data, out var type)) {
-			logger.Verbose("Received {MessageType} ({Bytes} B).", type.Name, data.Length);
-		}
-		else {
-			logger.Verbose("Received {Bytes} B message.", data.Length);
-		}
-	}
-}

Utils/Phantom.Utils.Rpc/Runtime/RpcCommonConnectionParameters.cs

@@ -0,0 +1,6 @@
+namespace Phantom.Utils.Rpc.Runtime;
+
+readonly record struct RpcCommonConnectionParameters(
+	ushort SendQueueCapacity,
+	TimeSpan PingInterval
+);

Utils/Phantom.Utils.Rpc/Runtime/RpcConnection.cs

@@ -1,40 +0,0 @@
-using Phantom.Utils.Actor;
-using Phantom.Utils.Rpc.Message;
-
-namespace Phantom.Utils.Rpc.Runtime;
-
-public abstract class RpcConnection<TMessageBase> {
-	private readonly MessageRegistry<TMessageBase> messageRegistry;
-	private readonly MessageReplyTracker replyTracker;
-	
-	internal RpcConnection(MessageRegistry<TMessageBase> messageRegistry, MessageReplyTracker replyTracker) {
-		this.messageRegistry = messageRegistry;
-		this.replyTracker = replyTracker;
-	}
-	
-	private protected abstract ValueTask Send(byte[] bytes);
-	
-	public async Task Send<TMessage>(TMessage message) where TMessage : TMessageBase {
-		var bytes = messageRegistry.Write(message).ToArray();
-		if (bytes.Length > 0) {
-			await Send(bytes);
-		}
-	}
-	
-	public async Task<TReply> Send<TMessage, TReply>(TMessage message, TimeSpan waitForReplyTime, CancellationToken waitForReplyCancellationToken) where TMessage : TMessageBase, ICanReply<TReply> {
-		var sequenceId = replyTracker.RegisterReply();
-		
-		var bytes = messageRegistry.Write<TMessage, TReply>(sequenceId, message).ToArray();
-		if (bytes.Length == 0) {
-			replyTracker.ForgetReply(sequenceId);
-			throw new ArgumentException("Could not write message.", nameof(message));
-		}
-		
-		await Send(bytes);
-		return await replyTracker.WaitForReply<TReply>(sequenceId, waitForReplyTime, waitForReplyCancellationToken);
-	}
-	
-	public void Receive(IReply message) {
-		replyTracker.ReceiveReply(message.SequenceId, message.SerializedReply);
-	}
-}

Utils/Phantom.Utils.Rpc/Runtime/RpcConnectionToClient.cs

@@ -1,41 +0,0 @@
-using NetMQ;
-using NetMQ.Sockets;
-using Phantom.Utils.Rpc.Message;
-
-namespace Phantom.Utils.Rpc.Runtime;
-
-public sealed class RpcConnectionToClient<TMessageBase> : RpcConnection<TMessageBase> {
-	private readonly ServerSocket socket;
-	private readonly uint routingId;
-	
-	internal event EventHandler<RpcClientConnectionClosedEventArgs>? Closed;
-	private bool isClosed;
-	
-	internal RpcConnectionToClient(ServerSocket socket, uint routingId, MessageRegistry<TMessageBase> messageRegistry, MessageReplyTracker replyTracker) : base(messageRegistry, replyTracker) {
-		this.socket = socket;
-		this.routingId = routingId;
-	}
-	
-	public bool IsSame(RpcConnectionToClient<TMessageBase> other) {
-		return this.routingId == other.routingId && this.socket == other.socket;
-	}
-	
-	public void Close() {
-		bool hasClosed = false;
-		
-		lock (this) {
-			if (!isClosed) {
-				isClosed = true;
-				hasClosed = true;
-			}
-		}
-		
-		if (hasClosed) {
-			Closed?.Invoke(this, new RpcClientConnectionClosedEventArgs(routingId));
-		}
-	}
-	
-	private protected override ValueTask Send(byte[] bytes) {
-		return socket.SendAsync(routingId, bytes);
-	}
-}

Utils/Phantom.Utils.Rpc/Runtime/RpcConnectionToServer.cs

@@ -1,25 +0,0 @@
-using NetMQ;
-using NetMQ.Sockets;
-using Phantom.Utils.Rpc.Message;
-using Phantom.Utils.Tasks;
-
-namespace Phantom.Utils.Rpc.Runtime;
-
-public sealed class RpcConnectionToServer<TMessageBase> : RpcConnection<TMessageBase> {
-	private readonly ClientSocket socket;
-	private readonly TaskCompletionSource isReady = AsyncTasks.CreateCompletionSource();
-	
-	public Task IsReady => isReady.Task;
-	
-	internal RpcConnectionToServer(ClientSocket socket, MessageRegistry<TMessageBase> messageRegistry, MessageReplyTracker replyTracker) : base(messageRegistry, replyTracker) {
-		this.socket = socket;
-	}
-	
-	public void SetIsReady() {
-		isReady.TrySetResult();
-	}
-	
-	private protected override ValueTask Send(byte[] bytes) {
-		return socket.SendAsync(bytes);
-	}
-}

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

@@ -0,0 +1,9 @@
+namespace Phantom.Utils.Rpc.Runtime;
+
+public enum RpcError : byte {
+	InvalidData = 0,
+	UnknownMessageRegistryCode = 1,
+	MessageDeserializationError = 2,
+	MessageHandlingError = 3,
+	MessageTooLarge = 4,
+}

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

@@ -0,0 +1,20 @@
+namespace Phantom.Utils.Rpc.Runtime;
+
+public 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.MessageDeserializationError => new RpcErrorException("Message deserialization error", error),
+			RpcError.MessageHandlingError        => new RpcErrorException("Message handling error", error),
+			RpcError.MessageTooLarge             => new RpcErrorException("Message is too large", error),
+			_                                    => new RpcErrorException("Unknown error", error),
+		};
+	}
+	
+	public RpcError Error { get; }
+	
+	internal RpcErrorException(string message, RpcError error) : base(message) {
+		this.Error = error;
+	}
+}

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

@@ -0,0 +1,47 @@
+using Phantom.Utils.Logging;
+using Phantom.Utils.Rpc.Frame;
+using Phantom.Utils.Rpc.Frame.Types;
+using Phantom.Utils.Rpc.Message;
+using Serilog;
+
+namespace Phantom.Utils.Rpc.Runtime;
+
+sealed class RpcFrameReader<TSentMessage, TReceivedMessage>(
+	string loggerName,
+	MessageRegistry<TReceivedMessage> messageRegistry,
+	RpcMessageHandler<TReceivedMessage> messageHandler,
+	RpcSendChannel<TSentMessage> sendChannel
+) : IFrameReader {
+	private readonly ILogger logger = PhantomLogger.Create<RpcFrameReader<TSentMessage, TReceivedMessage>>(loggerName);
+	
+	public ValueTask OnPing(DateTimeOffset pingTime, CancellationToken cancellationToken) {
+		messageHandler.OnPing();
+		return sendChannel.SendPong(pingTime, cancellationToken);
+	}
+	
+	public void OnPongFrame(PongFrame frame) {
+		sendChannel.ReceivePong(frame);
+	}
+	
+	public Task OnMessageFrame(MessageFrame frame, CancellationToken cancellationToken) {
+		if (messageRegistry.TryGetType(frame, out var messageType)) {
+			logger.Verbose("Received message {MesageId} of type {MessageType} ({Bytes} B).", frame.MessageId, messageType.Name, frame.SerializedMessage.Length);
+		}
+		
+		return messageRegistry.Handle(frame, messageHandler, cancellationToken);
+	}
+	
+	public void OnReplyFrame(ReplyFrame frame) {
+		logger.Verbose("Received reply to message {MesageId} ({Bytes} B).", frame.ReplyingToMessageId, frame.SerializedReply.Length);
+		sendChannel.ReceiveReply(frame);
+	}
+	
+	public void OnErrorFrame(ErrorFrame frame) {
+		logger.Warning("Received error response to message {MesageId}: {Error}", frame.ReplyingToMessageId, frame.Error);
+		sendChannel.ReceiveError(frame.ReplyingToMessageId, frame.Error);
+	}
+	
+	public void OnUnknownFrameStart(byte id) {
+		logger.Error("Received unknown frame ID: {FrameId}", id);
+	}
+}

Utils/Phantom.Utils.Rpc/Runtime/RpcHandshakeResult.cs

@@ -0,0 +1,6 @@
+namespace Phantom.Utils.Rpc.Runtime;
+
+enum RpcHandshakeResult : byte {
+	Success = 0,
+	InvalidAuthToken = 1,
+}

Utils/Phantom.Utils.Rpc/Runtime/RpcMessageHandler.cs

@@ -0,0 +1,19 @@
+using Phantom.Utils.Rpc.Message;
+
+namespace Phantom.Utils.Rpc.Runtime;
+
+sealed class RpcMessageHandler<TMessageBase>(IMessageReceiver<TMessageBase> receiver, IRpcReplySender replySender) {
+	public IMessageReceiver<TMessageBase> Receiver => receiver;
+	
+	public void OnPing() {
+		receiver.OnPing();
+	}
+	
+	public ValueTask SendReply<TReply>(uint messageId, TReply reply, CancellationToken cancellationToken) {
+		return replySender.SendReply(messageId, reply, cancellationToken);
+	}
+	
+	public ValueTask SendError(uint messageId, RpcError error, CancellationToken cancellationToken) {
+		return replySender.SendError(messageId, error, cancellationToken);
+	}
+}

Utils/Phantom.Utils.Rpc/Runtime/RpcReceiverActor.cs

@@ -1,75 +0,0 @@
-using Akka.Actor;
-using Akka.Event;
-using Phantom.Utils.Actor;
-using Phantom.Utils.Rpc.Message;
-
-namespace Phantom.Utils.Rpc.Runtime;
-
-sealed class RpcReceiverActor<TClientMessage, TServerMessage, TRegistrationMessage, TReplyMessage> : ReceiveActor<RpcReceiverActor<TClientMessage, TServerMessage, TRegistrationMessage, TReplyMessage>.ReceiveMessageCommand>, IWithStash where TRegistrationMessage : TServerMessage where TReplyMessage : TClientMessage, TServerMessage {
-	public readonly record struct Init(
-		string LoggerName,
-		IMessageDefinitions<TClientMessage, TServerMessage, TReplyMessage> MessageDefinitions,
-		IRegistrationHandler<TClientMessage, TServerMessage, TRegistrationMessage> RegistrationHandler,
-		RpcConnectionToClient<TClientMessage> Connection
-	);
-	
-	public static Props<ReceiveMessageCommand> Factory(Init init) {
-		return Props<ReceiveMessageCommand>.Create(() => new RpcReceiverActor<TClientMessage, TServerMessage, TRegistrationMessage, TReplyMessage>(init), new ActorConfiguration {
-			SupervisorStrategy = SupervisorStrategies.Resume,
-			StashCapacity = 100
-		});
-	}
-	
-	public IStash Stash { get; set; } = null!;
-	
-	private readonly string loggerName;
-	private readonly IMessageDefinitions<TClientMessage, TServerMessage, TReplyMessage> messageDefinitions;
-	private readonly IRegistrationHandler<TClientMessage, TServerMessage, TRegistrationMessage> registrationHandler;
-	private readonly RpcConnectionToClient<TClientMessage> connection;
-	
-	private RpcReceiverActor(Init init) {
-		this.loggerName = init.LoggerName;
-		this.messageDefinitions = init.MessageDefinitions;
-		this.registrationHandler = init.RegistrationHandler;
-		this.connection = init.Connection;
-		
-		ReceiveAsync<ReceiveMessageCommand>(ReceiveMessageUnauthorized);
-	}
-	
-	public sealed record ReceiveMessageCommand(Type MessageType, ReadOnlyMemory<byte> Data);
-	
-	private async Task ReceiveMessageUnauthorized(ReceiveMessageCommand command) {
-		if (command.MessageType == typeof(TRegistrationMessage)) {
-			await HandleRegistrationMessage(command);
-		}
-		else if (Stash.IsFull) {
-			Context.GetLogger().Warning("Stash is full, dropping message: {MessageType}", command.MessageType);
-		}
-		else {
-			Stash.Stash();
-		}
-	}
-	
-	private async Task HandleRegistrationMessage(ReceiveMessageCommand command) {
-		if (!messageDefinitions.ToServer.Read(command.Data, out TRegistrationMessage message)) {
-			return;
-		}
-		
-		var props = await registrationHandler.TryRegister(connection, message);
-		if (props == null) {
-			return;
-		}
-		
-		var handlerActor = Context.ActorOf(props, "Handler");
-		var replySender = new ReplySender<TClientMessage, TReplyMessage>(connection, messageDefinitions);
-		BecomeAuthorized(new MessageHandler<TServerMessage>(loggerName, handlerActor, replySender));
-	}
-	
-	private void BecomeAuthorized(MessageHandler<TServerMessage> handler) {
-		Stash.UnstashAll();
-		
-		Become(() => {
-			Receive<ReceiveMessageCommand>(command => messageDefinitions.ToServer.Handle(command.Data, handler));
-		});
-	}
-}

Utils/Phantom.Utils.Rpc/Runtime/RpcRuntime.cs

@@ -1,50 +0,0 @@
-using System.Diagnostics.CodeAnalysis;
-using NetMQ;
-using Phantom.Utils.Logging;
-using Phantom.Utils.Rpc.Message;
-using Phantom.Utils.Rpc.Sockets;
-using Serilog;
-
-namespace Phantom.Utils.Rpc.Runtime;
-
-public abstract class RpcRuntime<TSocket> where TSocket : ThreadSafeSocket {
-	private readonly TSocket socket;
-	
-	private protected string LoggerName { get; }
-	private protected ILogger RuntimeLogger { get; }
-	private protected MessageReplyTracker ReplyTracker { get; }
-	
-	protected RpcRuntime(RpcSocket<TSocket> socket) {
-		this.socket = socket.Socket;
-		
-		this.LoggerName = socket.Config.LoggerName;
-		this.RuntimeLogger = PhantomLogger.Create(LoggerName);
-		this.ReplyTracker = socket.ReplyTracker;
-	}
-	
-	protected async Task Launch() {
-		[SuppressMessage("ReSharper", "AccessToDisposedClosure")]
-		async Task RunTask() {
-			try {
-				await Run(socket);
-			} catch (Exception e) {
-				RuntimeLogger.Error(e, "Caught exception in RPC thread.");
-			}
-		}
-		
-		try {
-			await Task.Factory.StartNew(RunTask, CancellationToken.None, TaskCreationOptions.LongRunning, TaskScheduler.Default).Unwrap();
-		} catch (OperationCanceledException) {
-			// Ignore.
-		} finally {
-			await Disconnect(socket);
-			
-			socket.Dispose();
-			RuntimeLogger.Information("ZeroMQ runtime stopped.");
-		}
-	}
-	
-	private protected abstract Task Run(TSocket socket);
-	
-	private protected abstract Task Disconnect(TSocket socket);
-}

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

@@ -0,0 +1,157 @@
+using System.Diagnostics.CodeAnalysis;
+using System.Threading.Channels;
+using Phantom.Utils.Actor;
+using Phantom.Utils.Logging;
+using Phantom.Utils.Rpc.Frame;
+using Phantom.Utils.Rpc.Frame.Types;
+using Phantom.Utils.Rpc.Message;
+using Serilog;
+
+namespace Phantom.Utils.Rpc.Runtime;
+
+public sealed class RpcSendChannel<TMessageBase> : IRpcReplySender, IDisposable {
+	private readonly ILogger logger;
+	private readonly IRpcConnectionProvider connectionProvider;
+	private readonly MessageRegistry<TMessageBase> messageRegistry;
+	private readonly MessageReplyTracker messageReplyTracker;
+	
+	private readonly Channel<IFrame> sendQueue;
+	private readonly Task sendQueueTask;
+	private readonly Task pingTask;
+	
+	private readonly CancellationTokenSource pingCancellationTokenSource = new ();
+	
+	private uint nextMessageId;
+	private TaskCompletionSource<DateTimeOffset>? pongTask;
+	
+	internal RpcSendChannel(string loggerName, RpcCommonConnectionParameters connectionParameters, IRpcConnectionProvider connectionProvider, MessageRegistry<TMessageBase> messageRegistry) {
+		this.logger = PhantomLogger.Create<RpcSendChannel<TMessageBase>>(loggerName);
+		this.connectionProvider = connectionProvider;
+		this.messageRegistry = messageRegistry;
+		this.messageReplyTracker = new MessageReplyTracker(loggerName);
+		
+		this.sendQueue = Channel.CreateBounded<IFrame>(new BoundedChannelOptions(connectionParameters.SendQueueCapacity) {
+			AllowSynchronousContinuations = false,
+			FullMode = BoundedChannelFullMode.Wait,
+			SingleReader = true,
+			SingleWriter = false,
+		});
+		
+		this.sendQueueTask = ProcessSendQueue();
+		this.pingTask = Ping(connectionParameters.PingInterval);
+	}
+	
+	internal async ValueTask SendPong(DateTimeOffset pingTime, CancellationToken cancellationToken) {
+		await SendFrame(new PongFrame(pingTime), cancellationToken);
+	}
+	
+	public bool TrySendMessage<TMessage>(TMessage message) where TMessage : TMessageBase {
+		return sendQueue.Writer.TryWrite(NextMessageFrame(message));
+	}
+	
+	public async ValueTask SendMessage<TMessage>(TMessage message, CancellationToken cancellationToken = default) where TMessage : TMessageBase {
+		await SendFrame(NextMessageFrame(message), cancellationToken);
+	}
+	
+	public async Task<TReply> SendMessage<TMessage, TReply>(TMessage message, TimeSpan waitForReplyTime, CancellationToken cancellationToken) where TMessage : TMessageBase, ICanReply<TReply> {
+		MessageFrame frame = NextMessageFrame(message);
+		uint messageId = frame.MessageId;
+		
+		messageReplyTracker.RegisterReply(messageId);
+		try {
+			await SendFrame(frame, cancellationToken);
+		} catch (Exception) {
+			messageReplyTracker.ForgetReply(messageId);
+			throw;
+		}
+		
+		return await messageReplyTracker.WaitForReply<TReply>(messageId, waitForReplyTime, cancellationToken);
+	}
+	
+	async ValueTask IRpcReplySender.SendReply<TReply>(uint replyingToMessageId, TReply reply, CancellationToken cancellationToken) {
+		await SendFrame(new ReplyFrame(replyingToMessageId, Serialization.Serialize(reply)), cancellationToken);
+	}
+	
+	async ValueTask IRpcReplySender.SendError(uint replyingToMessageId, RpcError error, CancellationToken cancellationToken) {
+		await SendFrame(new ErrorFrame(replyingToMessageId, error), cancellationToken);
+	}
+	
+	private async ValueTask SendFrame(IFrame frame, CancellationToken cancellationToken) {
+		if (!sendQueue.Writer.TryWrite(frame)) {
+			await sendQueue.Writer.WriteAsync(frame, cancellationToken);
+		}
+	}
+	
+	private MessageFrame NextMessageFrame<T>(T message) where T : TMessageBase {
+		uint messageId = Interlocked.Increment(ref nextMessageId);
+		return messageRegistry.CreateFrame(messageId, message);
+	}
+	
+	private async Task ProcessSendQueue() {
+		await foreach (IFrame frame in sendQueue.Reader.ReadAllAsync()) {
+			while (true) {
+				try {
+					Stream stream = await connectionProvider.GetStream();
+					await stream.WriteAsync(frame.FrameType);
+					await frame.Write(stream);
+					await stream.FlushAsync();
+					break;
+				} catch (OperationCanceledException) {
+					throw;
+				} catch (Exception) {
+					// Retry.
+				}
+			}
+		}
+	}
+	
+	[SuppressMessage("ReSharper", "FunctionNeverReturns")]
+	private async Task Ping(TimeSpan interval) {
+		CancellationToken cancellationToken = pingCancellationTokenSource.Token;
+		
+		while (true) {
+			await Task.Delay(interval, cancellationToken);
+			
+			pongTask = new TaskCompletionSource<DateTimeOffset>();
+			
+			if (!sendQueue.Writer.TryWrite(PingFrame.Instance)) {
+				logger.Warning("Skipped a ping due to a full queue.");
+				continue;
+			}
+			
+			DateTimeOffset pingTime = await pongTask.Task;
+			DateTimeOffset currentTime = DateTimeOffset.UtcNow;
+			
+			TimeSpan roundTripTime = currentTime - pingTime;
+			logger.Information("Received pong (rtt: {RoundTripTime} ms).", (long) roundTripTime.TotalMilliseconds);
+		}
+	}
+	
+	internal void ReceivePong(PongFrame frame) {
+		pongTask?.TrySetResult(frame.PingTime);
+	}
+	
+	internal void ReceiveReply(ReplyFrame frame) {
+		messageReplyTracker.ReceiveReply(frame.ReplyingToMessageId, frame.SerializedReply);
+	}
+	
+	internal void ReceiveError(uint messageId, RpcError error) {
+		messageReplyTracker.FailReply(messageId, RpcErrorException.From(error));
+	}
+	
+	internal async Task Close() {
+		await pingCancellationTokenSource.CancelAsync();
+		sendQueue.Writer.TryComplete();
+		
+		try {
+			await Task.WhenAll(sendQueueTask, pingTask);
+		} catch (Exception) {
+			// Ignore.
+		}
+	}
+	
+	public void Dispose() {
+		sendQueueTask.Dispose();
+		pingCancellationTokenSource.Dispose();
+	}
+}

Utils/Phantom.Utils.Rpc/Runtime/RpcServerRuntime.cs

@@ -1,137 +0,0 @@
-using System.Collections.Concurrent;
-using Akka.Actor;
-using NetMQ.Sockets;
-using Phantom.Utils.Actor;
-using Phantom.Utils.Logging;
-using Phantom.Utils.Rpc.Message;
-using Phantom.Utils.Rpc.Sockets;
-using Serilog;
-using Serilog.Events;
-
-namespace Phantom.Utils.Rpc.Runtime;
-
-public static class RpcServerRuntime {
-	public static Task Launch<TClientMessage, TServerMessage, TRegistrationMessage, TReplyMessage>(
-		RpcConfiguration config,
-		IMessageDefinitions<TClientMessage, TServerMessage, TReplyMessage> messageDefinitions,
-		IRegistrationHandler<TClientMessage, TServerMessage, TRegistrationMessage> registrationHandler,
-		IActorRefFactory actorSystem,
-		CancellationToken cancellationToken
-	) where TRegistrationMessage : TServerMessage where TReplyMessage : TClientMessage, TServerMessage {
-		return RpcServerRuntime<TClientMessage, TServerMessage, TRegistrationMessage, TReplyMessage>.Launch(config, messageDefinitions, registrationHandler, actorSystem, cancellationToken);
-	}
-}
-
-internal sealed class RpcServerRuntime<TClientMessage, TServerMessage, TRegistrationMessage, TReplyMessage> : RpcRuntime<ServerSocket> where TRegistrationMessage : TServerMessage where TReplyMessage : TClientMessage, TServerMessage {
-	internal static Task Launch(RpcConfiguration config, IMessageDefinitions<TClientMessage, TServerMessage, TReplyMessage> messageDefinitions, IRegistrationHandler<TClientMessage, TServerMessage, TRegistrationMessage> registrationHandler, IActorRefFactory actorSystem, CancellationToken cancellationToken) {
-		var socket = RpcServerSocket.Connect(config);
-		return new RpcServerRuntime<TClientMessage, TServerMessage, TRegistrationMessage, TReplyMessage>(socket, messageDefinitions, registrationHandler, actorSystem, cancellationToken).Launch();
-	}
-	
-	private readonly string serviceName;
-	private readonly IMessageDefinitions<TClientMessage, TServerMessage, TReplyMessage> messageDefinitions;
-	private readonly IRegistrationHandler<TClientMessage, TServerMessage, TRegistrationMessage> registrationHandler;
-	private readonly IActorRefFactory actorSystem;
-	private readonly CancellationToken cancellationToken;
-	
-	private RpcServerRuntime(RpcServerSocket socket, IMessageDefinitions<TClientMessage, TServerMessage, TReplyMessage> messageDefinitions, IRegistrationHandler<TClientMessage, TServerMessage, TRegistrationMessage> registrationHandler, IActorRefFactory actorSystem, CancellationToken cancellationToken) : base(socket) {
-		this.serviceName = socket.Config.ServiceName;
-		this.messageDefinitions = messageDefinitions;
-		this.registrationHandler = registrationHandler;
-		this.actorSystem = actorSystem;
-		this.cancellationToken = cancellationToken;
-	}
-	
-	private protected override Task Run(ServerSocket socket) {
-		var clients = new ConcurrentDictionary<ulong, Client>();
-		
-		void OnConnectionClosed(object? sender, RpcClientConnectionClosedEventArgs e) {
-			if (clients.Remove(e.RoutingId, out var client)) {
-				client.Connection.Closed -= OnConnectionClosed;
-			}
-		}
-		
-		while (!cancellationToken.IsCancellationRequested) {
-			var (routingId, data) = socket.Receive(cancellationToken);
-			
-			if (data.Length == 0) {
-				LogUnknownMessage(routingId, data);
-				continue;
-			}
-			
-			Type? messageType = messageDefinitions.ToServer.TryGetType(data, out var type) ? type : null;
-			if (messageType == null) {
-				LogUnknownMessage(routingId, data);
-				continue;
-			}
-			
-			if (!clients.TryGetValue(routingId, out var client)) {
-				if (messageType != typeof(TRegistrationMessage)) {
-					RuntimeLogger.Warning("Received {MessageType} ({Bytes} B) from unregistered client {RoutingId}.", messageType.Name, data.Length, routingId);
-					continue;
-				}
-				
-				var clientLoggerName = LoggerName + ":" + routingId;
-				var clientActorName = "Rpc-" + serviceName + "-" + routingId;
-				
-				// TODO add pings and tear down connection after too much inactivity
-				var connection = new RpcConnectionToClient<TClientMessage>(socket, routingId, messageDefinitions.ToClient, ReplyTracker);
-				connection.Closed += OnConnectionClosed;
-				
-				client = new Client(clientLoggerName, clientActorName, connection, actorSystem, messageDefinitions, registrationHandler);
-				clients[routingId] = client;
-			}
-			
-			client.Enqueue(messageType, data);
-		}
-		
-		foreach (var client in clients.Values) {
-			client.Connection.Close();
-		}
-		
-		return Task.CompletedTask;
-	}
-	
-	private void LogUnknownMessage(uint routingId, ReadOnlyMemory<byte> data) {
-		RuntimeLogger.Warning("Received unknown message ({Bytes} B) from {RoutingId}.", data.Length, routingId);
-	}
-	
-	private protected override Task Disconnect(ServerSocket socket) {
-		return Task.CompletedTask;
-	}
-	
-	private sealed class Client {
-		public RpcConnectionToClient<TClientMessage> Connection { get; }
-		
-		private readonly ILogger logger;
-		private readonly ActorRef<RpcReceiverActor<TClientMessage, TServerMessage, TRegistrationMessage, TReplyMessage>.ReceiveMessageCommand> receiverActor;
-		
-		public Client(string loggerName, string actorName, RpcConnectionToClient<TClientMessage> connection, IActorRefFactory actorSystem, IMessageDefinitions<TClientMessage, TServerMessage, TReplyMessage> messageDefinitions, IRegistrationHandler<TClientMessage, TServerMessage, TRegistrationMessage> registrationHandler) {
-			this.Connection = connection;
-			this.Connection.Closed += OnConnectionClosed;
-			
-			this.logger = PhantomLogger.Create(loggerName);
-			
-			var receiverActorInit = new RpcReceiverActor<TClientMessage, TServerMessage, TRegistrationMessage, TReplyMessage>.Init(loggerName, messageDefinitions, registrationHandler, Connection);
-			this.receiverActor = actorSystem.ActorOf(RpcReceiverActor<TClientMessage, TServerMessage, TRegistrationMessage, TReplyMessage>.Factory(receiverActorInit), actorName + "-Receiver");
-		}
-		
-		internal void Enqueue(Type messageType, ReadOnlyMemory<byte> data) {
-			LogMessageType(messageType, data);
-			receiverActor.Tell(new RpcReceiverActor<TClientMessage, TServerMessage, TRegistrationMessage, TReplyMessage>.ReceiveMessageCommand(messageType, data));
-		}
-		
-		private void LogMessageType(Type messageType, ReadOnlyMemory<byte> data) {
-			if (logger.IsEnabled(LogEventLevel.Verbose)) {
-				logger.Verbose("Received {MessageType} ({Bytes} B).", messageType.Name, data.Length);
-			}
-		}
-		
-		private void OnConnectionClosed(object? sender, RpcClientConnectionClosedEventArgs e) {
-			Connection.Closed -= OnConnectionClosed;
-			
-			logger.Debug("Closing connection...");
-			receiverActor.Stop();
-		}
-	}
-}