Resolve sync with main

dotnet/samples/Concepts/Agents/ChatCompletion_ServiceSelection.cs

@@ -8,7 +8,7 @@ namespace Agents;
 
 /// <summary>
 /// Demonstrate service selection for <see cref="ChatCompletionAgent"/> through setting service-id
-/// on <see cref="ChatCompletionAgent.Arguments"/> and also providing override <see cref="KernelArguments"/>
+/// on <see cref="ChatHistoryKernelAgent.Arguments"/> and also providing override <see cref="KernelArguments"/>
 /// when calling <see cref="ChatCompletionAgent.InvokeAsync"/>
 /// </summary>
 public class ChatCompletion_ServiceSelection(ITestOutputHelper output) : BaseTest(output)

dotnet/src/Agents/Core/ChatCompletionAgent.cs

@@ -1,11 +1,8 @@
 // Copyright (c) Microsoft. All rights reserved.
 using System.Collections.Generic;
-using System.Globalization;
 using System.Runtime.CompilerServices;
 using System.Threading;
 using System.Threading.Tasks;
-using Microsoft.Extensions.Logging;
-using Microsoft.SemanticKernel.Agents.History;
 using Microsoft.SemanticKernel.ChatCompletion;
 using Microsoft.SemanticKernel.Services;
 
@@ -16,20 +13,12 @@ namespace Microsoft.SemanticKernel.Agents;
 /// </summary>
 /// <remarks>
 /// NOTE: Enable OpenAIPromptExecutionSettings.ToolCallBehavior for agent plugins.
-/// (<see cref="ChatCompletionAgent.Arguments"/>)
+/// (<see cref="ChatHistoryKernelAgent.Arguments"/>)
 /// </remarks>
-public sealed class ChatCompletionAgent : KernelAgent, IChatHistoryHandler
+public sealed class ChatCompletionAgent : ChatHistoryKernelAgent
 {
-    /// <summary>
-    /// Optional arguments for the agent.
-    /// </summary>
-    public KernelArguments? Arguments { get; init; }
-
-    /// <inheritdoc/>
-    public IChatHistoryReducer? HistoryReducer { get; init; }
-
     /// <inheritdoc/>
-    public async IAsyncEnumerable<ChatMessageContent> InvokeAsync(
+    public override async IAsyncEnumerable<ChatMessageContent> InvokeAsync(
         ChatHistory history,
         KernelArguments? arguments = null,
         Kernel? kernel = null,
@@ -74,7 +63,7 @@ await chatCompletionService.GetChatMessageContentsAsync(
     }
 
     /// <inheritdoc/>
-    public async IAsyncEnumerable<StreamingChatMessageContent> InvokeStreamingAsync(
+    public override async IAsyncEnumerable<StreamingChatMessageContent> InvokeStreamingAsync(
         ChatHistory history,
         KernelArguments? arguments = null,
         Kernel? kernel = null,
@@ -118,36 +107,6 @@ public async IAsyncEnumerable<StreamingChatMessageContent> InvokeStreamingAsync(
         }
     }
 
-    /// <inheritdoc/>
-    protected override IEnumerable<string> GetChannelKeys()
-    {
-        // Distinguish from other channel types.
-        yield return typeof(ChatHistoryChannel).FullName!;
-
-        // Agents with different reducers shall not share the same channel.
-        // Agents with the same or equivalent reducer shall share the same channel.
-        if (this.HistoryReducer != null)
-        {
-            // Explicitly include the reducer type to eliminate the possibility of hash collisions
-            // with custom implementations of IChatHistoryReducer.
-            yield return this.HistoryReducer.GetType().FullName!;
-
-            yield return this.HistoryReducer.GetHashCode().ToString(CultureInfo.InvariantCulture);
-        }
-    }
-
-    /// <inheritdoc/>
-    protected override Task<AgentChannel> CreateChannelAsync(CancellationToken cancellationToken)
-    {
-        ChatHistoryChannel channel =
-            new()
-            {
-                Logger = this.LoggerFactory.CreateLogger<ChatHistoryChannel>()
-            };
-
-        return Task.FromResult<AgentChannel>(channel);
-    }
-
     internal static (IChatCompletionService service, PromptExecutionSettings? executionSettings) GetChatCompletionService(Kernel kernel, KernelArguments? arguments)
     {
         // Need to provide a KernelFunction to the service selector as a container for the execution-settings.

dotnet/src/Agents/Core/ChatHistoryChannel.cs

@@ -5,13 +5,12 @@
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.SemanticKernel.Agents.Extensions;
-using Microsoft.SemanticKernel.Agents.History;
 using Microsoft.SemanticKernel.ChatCompletion;
 
 namespace Microsoft.SemanticKernel.Agents;
 
 /// <summary>
-/// A <see cref="AgentChannel"/> specialization for that acts upon a <see cref="IChatHistoryHandler"/>.
+/// A <see cref="AgentChannel"/> specialization for that acts upon a <see cref="ChatHistoryKernelAgent"/>.
 /// </summary>
 public sealed class ChatHistoryChannel : AgentChannel
 {
@@ -22,13 +21,13 @@ public sealed class ChatHistoryChannel : AgentChannel
         Agent agent,
         [EnumeratorCancellation] CancellationToken cancellationToken = default)
     {
-        if (agent is not IChatHistoryHandler historyHandler)
+        if (agent is not ChatHistoryKernelAgent historyAgent)
         {
             throw new KernelException($"Invalid channel binding for agent: {agent.Id} ({agent.GetType().FullName})");
         }
 
         // Pre-process history reduction.
-        await this._history.ReduceAsync(historyHandler.HistoryReducer, cancellationToken).ConfigureAwait(false);
+        await historyAgent.ReduceAsync(this._history, cancellationToken).ConfigureAwait(false);
 
         // Capture the current message count to evaluate history mutation.
         int messageCount = this._history.Count;
@@ -38,7 +37,7 @@ public sealed class ChatHistoryChannel : AgentChannel
         Queue<ChatMessageContent> messageQueue = [];
 
         ChatMessageContent? yieldMessage = null;
-        await foreach (ChatMessageContent responseMessage in historyHandler.InvokeAsync(this._history, null, null, cancellationToken).ConfigureAwait(false))
+        await foreach (ChatMessageContent responseMessage in historyAgent.InvokeAsync(this._history, null, null, cancellationToken).ConfigureAwait(false))
         {
             // Capture all messages that have been included in the mutated the history.
             for (int messageIndex = messageCount; messageIndex < this._history.Count; messageIndex++)

dotnet/src/Agents/Core/ChatHistoryKernelAgent.cs

@@ -0,0 +1,80 @@
+// Copyright (c) Microsoft. All rights reserved.
+using System.Collections.Generic;
+using System.Globalization;
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.Extensions.Logging;
+using Microsoft.SemanticKernel.Agents.History;
+using Microsoft.SemanticKernel.ChatCompletion;
+
+namespace Microsoft.SemanticKernel.Agents;
+
+/// <summary>
+/// A <see cref="KernelAgent"/> specialization bound to a <see cref="ChatHistoryChannel"/>.
+/// </summary>
+/// <remarks>
+/// NOTE: Enable OpenAIPromptExecutionSettings.ToolCallBehavior for agent plugins.
+/// (<see cref="ChatHistoryKernelAgent.Arguments"/>)
+/// </remarks>
+public abstract class ChatHistoryKernelAgent : KernelAgent
+{
+    /// <summary>
+    /// Optional arguments for the agent.
+    /// </summary>
+    public KernelArguments? Arguments { get; init; }
+
+    /// <inheritdoc/>
+    public IChatHistoryReducer? HistoryReducer { get; init; }
+
+    /// <inheritdoc/>
+    public abstract IAsyncEnumerable<ChatMessageContent> InvokeAsync(
+        ChatHistory history,
+        KernelArguments? arguments = null,
+        Kernel? kernel = null,
+        CancellationToken cancellationToken = default);
+
+    /// <inheritdoc/>
+    public abstract IAsyncEnumerable<StreamingChatMessageContent> InvokeStreamingAsync(
+        ChatHistory history,
+        KernelArguments? arguments = null,
+        Kernel? kernel = null,
+        CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// Reduce the provided history
+    /// </summary>
+    /// <param name="history">The source history</param>
+    /// <param name="cancellationToken">The <see cref="CancellationToken"/> to monitor for cancellation requests. The default is <see cref="CancellationToken.None"/>.</param>
+    /// <returns></returns>
+    public Task<bool> ReduceAsync(ChatHistory history, CancellationToken cancellationToken = default) =>
+        history.ReduceAsync(this.HistoryReducer, cancellationToken);
+
+    /// <inheritdoc/>
+    protected sealed override IEnumerable<string> GetChannelKeys()
+    {
+        yield return typeof(ChatHistoryChannel).FullName!;
+
+        // Agents with different reducers shall not share the same channel.
+        // Agents with the same or equivalent reducer shall share the same channel.
+        if (this.HistoryReducer != null)
+        {
+            // Explicitly include the reducer type to eliminate the possibility of hash collisions
+            // with custom implementations of IChatHistoryReducer.
+            yield return this.HistoryReducer.GetType().FullName!;
+
+            yield return this.HistoryReducer.GetHashCode().ToString(CultureInfo.InvariantCulture);
+        }
+    }
+
+    /// <inheritdoc/>
+    protected sealed override Task<AgentChannel> CreateChannelAsync(CancellationToken cancellationToken)
+    {
+        ChatHistoryChannel channel =
+            new()
+            {
+                Logger = this.LoggerFactory.CreateLogger<ChatHistoryChannel>()
+            };
+
+        return Task.FromResult<AgentChannel>(channel);
+    }
+}

dotnet/src/Agents/UnitTests/Core/ChatHistoryChannelTests.cs

@@ -15,7 +15,7 @@ public class ChatHistoryChannelTests
 {
     /// <summary>
     /// Verify a <see cref="ChatHistoryChannel"/> throws if passed an agent that
-    /// does not implement <see cref="IChatHistoryHandler"/>.
+    /// does not implement <see cref="ChatHistoryKernelAgent"/>.
     /// </summary>
     [Fact]
     public async Task VerifyAgentWithoutIChatHistoryHandlerAsync()

dotnet/src/Agents/UnitTests/MockAgent.cs

@@ -1,29 +1,23 @@
 // Copyright (c) Microsoft. All rights reserved.
-using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Threading;
-using System.Threading.Tasks;
-using Microsoft.Extensions.Logging;
 using Microsoft.SemanticKernel;
 using Microsoft.SemanticKernel.Agents;
-using Microsoft.SemanticKernel.Agents.History;
 using Microsoft.SemanticKernel.ChatCompletion;
 
 namespace SemanticKernel.Agents.UnitTests;
 
 /// <summary>
-/// Mock definition of <see cref="KernelAgent"/> with a <see cref="IChatHistoryHandler"/> contract.
+/// Mock definition of <see cref="KernelAgent"/> with a <see cref="ChatHistoryKernelAgent"/> contract.
 /// </summary>
-internal class MockAgent : KernelAgent, IChatHistoryHandler
+internal class MockAgent : ChatHistoryKernelAgent
 {
     public int InvokeCount { get; private set; }
 
     public IReadOnlyList<ChatMessageContent> Response { get; set; } = [];
 
-    public IChatHistoryReducer? HistoryReducer { get; init; }
-
-    public IAsyncEnumerable<ChatMessageContent> InvokeAsync(
+    public override IAsyncEnumerable<ChatMessageContent> InvokeAsync(
         ChatHistory history,
         KernelArguments? arguments = null,
         Kernel? kernel = null,
@@ -34,7 +28,7 @@ public IAsyncEnumerable<ChatMessageContent> InvokeAsync(
         return this.Response.ToAsyncEnumerable();
     }
 
-    public IAsyncEnumerable<StreamingChatMessageContent> InvokeStreamingAsync(
+    public override IAsyncEnumerable<StreamingChatMessageContent> InvokeStreamingAsync(
         ChatHistory history,
         KernelArguments? arguments = null,
         Kernel? kernel = null,
@@ -43,22 +37,4 @@ public IAsyncEnumerable<StreamingChatMessageContent> InvokeStreamingAsync(
         this.InvokeCount++;
         return this.Response.Select(m => new StreamingChatMessageContent(m.Role, m.Content)).ToAsyncEnumerable();
     }
-
-    /// <inheritdoc/>
-    protected internal override IEnumerable<string> GetChannelKeys()
-    {
-        yield return Guid.NewGuid().ToString();
-    }
-
-    /// <inheritdoc/>
-    protected internal override Task<AgentChannel> CreateChannelAsync(CancellationToken cancellationToken)
-    {
-        ChatHistoryChannel channel =
-            new()
-            {
-                Logger = this.LoggerFactory.CreateLogger<ChatHistoryChannel>()
-            };
-
-        return Task.FromResult<AgentChannel>(channel);
-    }
 }