add python equiv in core

dotnet/src/Microsoft.AutoGen/Core/PythonEquiv/IHandle.cs

@@ -0,0 +1,30 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// IHandle.cs
+
+using Google.Protobuf;
+
+namespace Microsoft.AutoGen.Core.Python;
+
+/// <summary>
+/// Defines a handler interface for processing items of type <typeparamref name="T"/>.
+/// </summary>
+/// <typeparam name="T">The type of item to be handled, which must implement <see cref="IMessage"/>.</typeparam>
+public interface IHandle<in T> where T : IMessage
+{
+    /// <summary>
+    /// Handles the specified item asynchronously.
+    /// </summary>
+    /// <param name="item">The item to be handled.</param>
+    /// <returns>A task that represents the asynchronous operation.</returns>
+    Task Handle(T item, CancellationToken cancellationToken = default);
+}
+
+public interface IHandle<in InT, OutT> where InT : IMessage where OutT : IMessage
+{
+    /// <summary>
+    /// Handles the specified item asynchronously.
+    /// </summary>
+    /// <param name="item">The item to be handled.</param>
+    /// <returns>A task that represents the asynchronous operation.</returns>
+    Task<OutT> Handle(InT item, CancellationToken cancellationToken = default);
+}

dotnet/src/Microsoft.AutoGen/Core/PythonEquiv/IHandleExtensions.cs

@@ -0,0 +1,38 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// IHandleExtensions.cs
+
+using System.Reflection;
+
+namespace Microsoft.AutoGen.Core.Python;
+
+/// <summary>
+/// Provides extension methods for types implementing the IHandle interface.
+/// </summary>
+public static class IHandleExtensions
+{
+    /// <summary>
+    /// Gets all the handler methods from the interfaces implemented by the specified type.
+    /// </summary>
+    /// <param name="type">The type to get the handler methods from.</param>
+    /// <returns>An array of MethodInfo objects representing the handler methods.</returns>
+    public static MethodInfo[] GetHandlers(this Type type)
+    {
+        var handlers = type.GetInterfaces().Where(i => i.IsGenericType && (i.GetGenericTypeDefinition() == typeof(IHandle<>) || i.GetGenericTypeDefinition() == typeof(IHandle<,>)));
+        return handlers.SelectMany(h => h.GetMethods().Where(m => m.Name == "Handle")).ToArray();
+    }
+
+    /// <summary>
+    /// Gets a lookup table of handler methods from the interfaces implemented by the specified type.
+    /// </summary>
+    /// <param name="type">The type to get the handler methods from.</param>
+    /// <returns>A dictionary where the key is the generic type and the value is the MethodInfo of the handler method.</returns>
+    public static Dictionary<Type, MethodInfo> GetHandlersLookupTable(this Type type)
+    {
+        var handlers = type.GetHandlers();
+        return handlers.ToDictionary(h =>
+        {
+            var generic = h.DeclaringType!.GetGenericArguments();
+            return generic[0];
+        });
+    }
+}