feat: Instrument dev-server to expose in diagnostics in client

src/Uno.UI.RemoteControl.Messaging/DevServerDiagnostics.cs

@@ -0,0 +1,35 @@
+#nullable enable
+using System;
+using System.Linq;
+using System.Threading;
+using Uno.UI.RemoteControl.HotReload.Messages;
+
+namespace Uno.UI.RemoteControl;
+
+public static class DevServerDiagnostics
+{
+	private static readonly AsyncLocal<ISink> _current = new();
+
+	/// <summary>
+	/// Gets the current (async-local) sink for dev-server diagnostics.
+	/// </summary>
+	public static ISink Current
+	{
+		get => _current.Value ?? NullSink.Instance;
+		set => _current.Value = value;
+	}
+
+	public interface ISink
+	{
+		void ReportInvalidFrame<TContent>(Frame frame);
+	}
+
+	private class NullSink : ISink
+	{
+		public static NullSink Instance { get; } = new();
+
+		public void ReportInvalidFrame<TContent>(Frame frame)
+		{
+		}
+	}
+}

src/Uno.UI.RemoteControl.Messaging/IRemoteControlServer.cs

@@ -9,7 +9,7 @@ public interface IRemoteControlServer
 	{
 		string GetServerConfiguration(string key);
 
-		Task SendFrame(IMessage fileReload);
+		Task SendFrame(IMessage message);
 
 		Task SendMessageToIDEAsync(IdeMessage message);
 	}

src/Uno.UI.RemoteControl.Messaging/Messages/Frame.cs

@@ -1,60 +1,88 @@
-using System;
+#nullable enable
+
+using System;
 using System.Collections.Generic;
 using System.Diagnostics;
+using System.Diagnostics.CodeAnalysis;
 using System.IO;
 using System.Text;
 using Newtonsoft.Json;
 
-namespace Uno.UI.RemoteControl.HotReload.Messages
+namespace Uno.UI.RemoteControl.HotReload.Messages;
+
+[DebuggerDisplay("{Name}-{Scope}")]
+public class Frame
 {
-	[DebuggerDisplay("{Name}-{Scope}")]
-	public class Frame
+	public Frame(short version, string scope, string name, string content)
 	{
-		public Frame(short version, string scope, string name, string content)
-		{
-			Version = version;
-			Scope = scope;
-			Name = name;
-			Content = content;
-		}
+		Version = version;
+		Scope = scope;
+		Name = name;
+		Content = content;
+	}
 
-		public int Version { get; }
+	public int Version { get; }
 
-		public string Scope { get; }
+	public string Scope { get; }
 
-		public string Name { get; }
+	public string Name { get; }
 
-		public string Content { get; }
+	public string Content { get; }
 
-		public static Frame Read(Stream stream)
+	public static Frame Read(Stream stream)
+	{
+		using (var reader = new BinaryReader(stream, Encoding.UTF8))
 		{
-			using (var reader = new BinaryReader(stream, Encoding.UTF8))
-			{
-				var version = reader.ReadInt16();
-				var scope = reader.ReadString();
-				var name = reader.ReadString();
-				var content = reader.ReadString();
+			var version = reader.ReadInt16();
+			var scope = reader.ReadString();
+			var name = reader.ReadString();
+			var content = reader.ReadString();
 
-				return new Frame(version, scope, name, content);
-			}
+			return new Frame(version, scope, name, content);
 		}
+	}
 
-		public static Frame Create<T>(short version, string scope, string name, T content)
-			=> new Frame(
-				version,
-				scope,
-				name,
-				JsonConvert.SerializeObject(content)
-			);
+	public static Frame Create<T>(short version, string scope, string name, T content)
+		=> new Frame(
+			version,
+			scope,
+			name,
+			JsonConvert.SerializeObject(content)
+		);
 
-		public void WriteTo(Stream stream)
-		{
-			var writer = new BinaryWriter(stream, Encoding.UTF8);
+	public T GetContent<T>()
+		=> TryGetContent<T>(out var content) ? content : throw new InvalidOperationException("Invalid frame");
 
-			writer.Write((short)Version);
-			writer.Write(Scope);
-			writer.Write(Name);
-			writer.Write(Content);
+	public bool TryGetContent<T>([NotNullWhen(true)] out T? content)
+	{
+		try
+		{
+			content = JsonConvert.DeserializeObject<T>(Content);
+			if (content is not null)
+			{
+				return true;
+			}
+			else
+			{
+				DevServerDiagnostics.Current.ReportInvalidFrame<T>(this);
+				return false;
+			}
 		}
+		catch (Exception)
+		{
+			DevServerDiagnostics.Current.ReportInvalidFrame<T>(this);
+			content = default;
+			return false;
+		}
+	}
+
+	public void WriteTo(Stream stream)
+	{
+		var writer = new BinaryWriter(stream, Encoding.UTF8);
+
+		writer.Write((short)Version);
+		writer.Write(Scope);
+		writer.Write(Name);
+		writer.Write(Content);
 	}
 }

src/Uno.UI.RemoteControl.Messaging/WellKnownScopes.cs

@@ -0,0 +1,28 @@
+#nullable enable
+using System;
+using System.Linq;
+
+namespace Uno.UI.RemoteControl;
+
+public static class WellKnownScopes
+{
+	/// <summary>
+	/// Reserved for internal usage of communication channel between dev-server and IDE (i.e. KeepAliveIdeMessage).
+	/// </summary>
+	public const string IdeChannel = "IdeChannel";
+
+	/// <summary>
+	/// Reserved for internal usage of communication channel between dev-server and client (i.e. KeepAliveMessage).
+	/// </summary>
+	public const string DevServerChannel = "RemoteControlServer";
+
+	/// <summary>
+	/// For hot-reload messages, client, server and IDE.
+	/// </summary>
+	public const string HotReload = "HotReload";
+
+	/// <summary>
+	/// For messages used for testing purpose (e.g. UpdateFile)
+	/// </summary>
+	public const string Testing = "UnoRuntimeTests";
+}

src/Uno.UI.RemoteControl.Messaging/_Compat/IsExternalInit.cs

@@ -0,0 +1,9 @@
+#nullable enable
+using System;
+using System.Linq;
+
+namespace System.Runtime.CompilerServices;
+
+internal static class IsExternalInit
+{
+}

src/Uno.UI.RemoteControl.Messaging/_Compat/NotNullWhenAttribute.cs

@@ -0,0 +1,25 @@
+#nullable enable
+using System;
+using System.Linq;
+
+namespace System.Diagnostics.CodeAnalysis;
+
+/// <summary>
+/// Specifies that when a method returns <see cref="ReturnValue"/>, the parameter will not be null even if the corresponding type allows it.
+/// </summary>
+[global::System.AttributeUsage(global::System.AttributeTargets.Parameter, Inherited = false)]
+[global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
+internal sealed class NotNullWhenAttribute : global::System.Attribute
+{
+	/// <summary>
+	/// Initializes the attribute with the specified return value condition.
+	/// </summary>
+	/// <param name="returnValue">The return value condition. If the method returns this value, the associated parameter will not be null.</param>
+	public NotNullWhenAttribute(bool returnValue)
+	{
+		ReturnValue = returnValue;
+	}
+
+	/// <summary>Gets the return value condition.</summary>
+	public bool ReturnValue { get; }
+}

src/Uno.UI.RemoteControl.Server/Uno.UI.RemoteControl.Server.csproj

@@ -7,6 +7,7 @@
 	</PropertyGroup>
 
 	<ItemGroup>
+		<Compile Include="..\Uno.UI.RemoteControl\Helpers\VersionHelper.cs" Link="Helpers/%(Filename)" />
 		<Compile Include="..\Uno.UI.RemoteControl\Messages\**\*.cs" Link="Messages/%(Filename)" />
 	</ItemGroup>
 

src/Uno.UI.RemoteControl/Helpers/VersionHelper.cs

@@ -0,0 +1,32 @@
+using System;
+using System.Linq;
+using System.Reflection;
+
+namespace Uno.UI.RemoteControl.Helpers;
+
+internal class VersionHelper
+{
+	public static string GetVersion(Type type)
+		=> GetVersion(type.Assembly);
+
+	public static string GetVersion(Assembly assembly)
+	{
+		if (assembly
+			.GetCustomAttributesData()
+			.FirstOrDefault(data => data.AttributeType.Name.Contains("AssemblyInformationalVersion", StringComparison.OrdinalIgnoreCase))
+			?.ConstructorArguments
+			.FirstOrDefault()
+			.Value
+			?.ToString() is { Length: > 0 } informationalVersion)
+		{
+			return informationalVersion;
+		}
+
+		if (assembly.GetName().Version is { } assemblyVersion)
+		{
+			return assemblyVersion.ToString();
+		}
+
+		return "--unknown--";
+	}
+}

src/Uno.UI.RemoteControl/HotReload/ClientHotReloadProcessor.cs

@@ -15,7 +15,7 @@
 
 namespace Uno.UI.RemoteControl.HotReload;
 
-public partial class ClientHotReloadProcessor : IRemoteControlProcessor
+public partial class ClientHotReloadProcessor : IClientProcessor
 {
 	private string? _projectPath;
 	private string[]? _xamlPaths;

src/Uno.UI.RemoteControl/IRemoteControlProcessor.cs → src/Uno.UI.RemoteControl/IClientProcessor.cs

@@ -6,7 +6,7 @@
 
 namespace Uno.UI.RemoteControl;
 
-internal interface IRemoteControlProcessor
+internal interface IClientProcessor
 {
 	string Scope { get; }
 

src/Uno.UI.RemoteControl/Messages/KeepAliveMessage.cs

@@ -1,15 +1,28 @@
-namespace Uno.UI.RemoteControl.Messages
+using System;
+using Uno.UI.RemoteControl.Helpers;
+
+namespace Uno.UI.RemoteControl.Messages;
+
+public record KeepAliveMessage : IMessage
 {
-	public class KeepAliveMessage : IMessage
-	{
-		public const string Name = nameof(KeepAliveMessage);
+	private static readonly string _localVersion = VersionHelper.GetVersion(typeof(KeepAliveMessage));
+
+	public const string Name = nameof(KeepAliveMessage);
+
+	public string Scope => WellKnownScopes.DevServerChannel;
+
+	string IMessage.Name => Name;
 
-		public KeepAliveMessage()
-		{
-		}
+	/// <summary>
+	/// The version of the dev-server version of the sender.
+	/// </summary>
+	public string? AssemblyVersion { get; init; } = _localVersion;
 
-		public string Scope => "RemoteControlServer";
+	/// <summary>
+	/// Sequence ID of the ping.
+	/// </summary>
+	public ulong SequenceId { get; init; }
 
-		string IMessage.Name => Name;
-	}
+	public KeepAliveMessage Next()
+		=> this with { SequenceId = SequenceId + 1 };
 }

src/Uno.UI.RemoteControl/Messages/ProcessorsDiscovery.cs

@@ -1,21 +1,22 @@
-namespace Uno.UI.RemoteControl.Messages
+using static Uno.UI.RemoteControl.Messages.ProcessorsDiscoveryResponse;
+
+namespace Uno.UI.RemoteControl.Messages;
+
+public class ProcessorsDiscovery : IMessage
 {
-	public class ProcessorsDiscovery : IMessage
-	{
-		public const string Name = nameof(ProcessorsDiscovery);
+	public const string Name = nameof(ProcessorsDiscovery);
 
-		public ProcessorsDiscovery(string basePath, string appInstanceId = "")
-		{
-			BasePath = basePath;
-			AppInstanceId = appInstanceId;
-		}
+	public ProcessorsDiscovery(string basePath, string appInstanceId = "")
+	{
+		BasePath = basePath;
+		AppInstanceId = appInstanceId;
+	}
 
-		public string Scope => "RemoteControlServer";
+	public string Scope => WellKnownScopes.DevServerChannel;
 
-		string IMessage.Name => Name;
+	string IMessage.Name => Name;
 
-		public string BasePath { get; }
+	public string BasePath { get; }
 
-		public string AppInstanceId { get; }
-	}
+	public string AppInstanceId { get; }
 }

src/Uno.UI.RemoteControl/Messages/ProcessorsDiscoveryResponse.cs

@@ -0,0 +1,16 @@
+using System;
+using System.Collections.Immutable;
+using System.Linq;
+
+namespace Uno.UI.RemoteControl.Messages;
+
+public record ProcessorsDiscoveryResponse(IImmutableList<string> Assemblies, IImmutableList<DiscoveredProcessor> Processors) : IMessage
+{
+	public const string Name = nameof(ProcessorsDiscoveryResponse);
+
+	public string Scope => WellKnownScopes.DevServerChannel;
+
+	string IMessage.Name => Name;
+}
+
+public record DiscoveredProcessor(string AssemblyPath, string Type, string Version, bool IsLoaded, string? LoadError = null);