.NET: [BREAKING] Subclass AgentThread so that different agents have their own threads with their own typed settings. (#798)

* Subclass AgentThread so that different agents have their own threads with their own typed settings. * Address PR comment. * Add unit tests for base abstract threads * Fix style warning * Fix stlying * FIx and suppress warnings as needed. * Remove covariant thread response types and fix some styling. * Remove unecessary json property name attributes and make OrchestratingAgentThread private * Fix break from merge from main. * Fix formatting * Fix deserialization bug in Memory sample * Remove thread deletion from basic samples. * Remove public constructors for thread subclasses and add more factory methods to concrete agent types. * Update AgentProxy thread constructors to be internal as well. * Revert AgentProxyThread to internal * Change AIContextProvider to internal set * Change conversation id and message store properties to internal set * Update styling. * Seal various thread types. * Add thread type check for thread deletion * Fix tests after latest merge from main * Add thread type checks for thread deletion. --------- Co-authored-by: Chris <66376200+crickman@users.noreply.github.com>
2026-06-16 21:04:09 +08:00 · 2025-09-23 11:30:06 +01:00
parent 230cb083ce
commit 3571a7d321
68 changed files with 1774 additions and 613 deletions
@@ -0,0 +1,96 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.Collections.Generic;
+using System.Text.Json;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace Microsoft.Extensions.AI.Agents;
+
+/// <summary>
+/// A base class for agent threads that operate entirely in memory without external storage.
+/// </summary>
+public abstract class InMemoryAgentThread : AgentThread
+{
+    /// <summary>
+    /// Initializes a new instance of the <see cref="InMemoryAgentThread"/> class.
+    /// </summary>
+    /// <param name="messageStore">An optional <see cref="InMemoryChatMessageStore"/> to use for storing chat messages. If null, a new instance will be created.</param>
+    protected InMemoryAgentThread(InMemoryChatMessageStore? messageStore = null)
+    {
+        this.MessageStore = messageStore ?? new InMemoryChatMessageStore();
+    }
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="InMemoryAgentThread"/> class with the specified initial messages.
+    /// </summary>
+    /// <param name="messages">The messages to initialize the thread with.</param>
+    protected InMemoryAgentThread(IEnumerable<ChatMessage> messages)
+    {
+        this.MessageStore = new InMemoryChatMessageStore();
+        foreach (var message in messages)
+        {
+            this.MessageStore.Add(message);
+        }
+    }
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="InMemoryAgentThread"/> class from serialized state.
+    /// </summary>
+    /// <param name="serializedThreadState">A <see cref="JsonElement"/> representing the serialized state of the thread.</param>
+    /// <param name="jsonSerializerOptions">Optional settings for customizing the JSON deserialization process.</param>
+    /// <param name="messageStoreFactory">A factory function to create the <see cref="InMemoryChatMessageStore"/> from its serialized state.</param>
+    /// <exception cref="ArgumentException">The <paramref name="serializedThreadState"/> is not a JSON object.</exception>
+    /// <exception cref="JsonException">The <paramref name="serializedThreadState"/> is invalid or cannot be deserialized to the expected type.</exception>
+    protected InMemoryAgentThread(
+        JsonElement serializedThreadState,
+        JsonSerializerOptions? jsonSerializerOptions = null,
+        Func<JsonElement, JsonSerializerOptions?, InMemoryChatMessageStore>? messageStoreFactory = null)
+    {
+        if (serializedThreadState.ValueKind != JsonValueKind.Object)
+        {
+            throw new ArgumentException("The serialized thread state must be a JSON object.", nameof(serializedThreadState));
+        }
+
+        var state = JsonSerializer.Deserialize(
+            serializedThreadState,
+            AgentAbstractionsJsonUtilities.DefaultOptions.GetTypeInfo(typeof(InMemoryAgentThreadState))) as InMemoryAgentThreadState;
+
+        this.MessageStore =
+            messageStoreFactory?.Invoke(state?.StoreState ?? default, jsonSerializerOptions) ??
+            new InMemoryChatMessageStore(state?.StoreState ?? default, jsonSerializerOptions);
+    }
+
+    /// <summary>
+    /// Gets or sets the <see cref="InMemoryChatMessageStore"/> used by this thread.
+    /// </summary>
+    public InMemoryChatMessageStore MessageStore { get; }
+
+    /// <summary>
+    /// Serializes the current object's state to a <see cref="JsonElement"/> using the specified serialization options.
+    /// </summary>
+    /// <param name="jsonSerializerOptions">The JSON serialization options to use.</param>
+    /// <param name="cancellationToken">The <see cref="CancellationToken"/> to monitor for cancellation requests. The default is <see cref="CancellationToken.None"/>.</param>
+    /// <returns>A <see cref="JsonElement"/> representation of the object's state.</returns>
+    public override async Task<JsonElement> SerializeAsync(JsonSerializerOptions? jsonSerializerOptions = null, CancellationToken cancellationToken = default)
+    {
+        var storeState = await this.MessageStore.SerializeStateAsync(jsonSerializerOptions, cancellationToken).ConfigureAwait(false);
+
+        var state = new InMemoryAgentThreadState
+        {
+            StoreState = storeState,
+        };
+
+        return JsonSerializer.SerializeToElement(state, AgentAbstractionsJsonUtilities.DefaultOptions.GetTypeInfo(typeof(InMemoryAgentThreadState)));
+    }
+
+    /// <inheritdoc />
+    protected internal override Task MessagesReceivedAsync(IEnumerable<ChatMessage> newMessages, CancellationToken cancellationToken = default)
+        => this.MessageStore.AddMessagesAsync(newMessages, cancellationToken);
+
+    internal sealed class InMemoryAgentThreadState
+    {
+        public JsonElement? StoreState { get; set; }
+    }
+}