chore: import upstream snapshot with attribution

dotnet/src/Microsoft.Agents.AI.DurableTask/DurableDataConverter.cs

@@ -0,0 +1,66 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System.Diagnostics.CodeAnalysis;
+using System.Text.Json;
+using System.Text.Json.Serialization.Metadata;
+using Microsoft.Agents.AI.DurableTask.State;
+using Microsoft.DurableTask;
+
+namespace Microsoft.Agents.AI.DurableTask;
+
+/// <summary>
+/// Custom data converter for durable agents and workflows that ensures proper JSON serialization.
+/// </summary>
+/// <remarks>
+/// This converter handles special cases like <see cref="DurableAgentState"/> using source-generated
+/// JSON contexts for AOT compatibility, and falls back to reflection-based serialization for other types.
+/// </remarks>
+internal sealed class DurableDataConverter : DataConverter
+{
+    private static readonly JsonSerializerOptions s_options = new(DurableAgentJsonUtilities.DefaultOptions)
+    {
+        PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
+        PropertyNameCaseInsensitive = true,
+    };
+
+    [UnconditionalSuppressMessage("Trimming", "IL2026", Justification = "Fallback uses reflection when metadata unavailable.")]
+    [UnconditionalSuppressMessage("AOT", "IL3050", Justification = "Fallback uses reflection when metadata unavailable.")]
+    public override object? Deserialize(string? data, Type targetType)
+    {
+        if (data is null)
+        {
+            return null;
+        }
+
+        if (targetType == typeof(DurableAgentState))
+        {
+            return JsonSerializer.Deserialize(data, DurableAgentStateJsonContext.Default.DurableAgentState);
+        }
+
+        JsonTypeInfo? typeInfo = s_options.GetTypeInfo(targetType);
+        return typeInfo is not null
+            ? JsonSerializer.Deserialize(data, typeInfo)
+            : JsonSerializer.Deserialize(data, targetType, s_options);
+    }
+
+    [return: NotNullIfNotNull(nameof(value))]
+    [UnconditionalSuppressMessage("Trimming", "IL2026", Justification = "Fallback uses reflection when metadata unavailable.")]
+    [UnconditionalSuppressMessage("AOT", "IL3050", Justification = "Fallback uses reflection when metadata unavailable.")]
+    public override string? Serialize(object? value)
+    {
+        if (value is null)
+        {
+            return null;
+        }
+
+        if (value is DurableAgentState durableAgentState)
+        {
+            return JsonSerializer.Serialize(durableAgentState, DurableAgentStateJsonContext.Default.DurableAgentState);
+        }
+
+        JsonTypeInfo? typeInfo = s_options.GetTypeInfo(value.GetType());
+        return typeInfo is not null
+            ? JsonSerializer.Serialize(value, typeInfo)
+            : JsonSerializer.Serialize(value, s_options);
+    }
+}