Integrate BotSharp with Microsoft Agent Framework via A2A protocol

src/Infrastructure/BotSharp.Abstraction/Agents/Enums/AgentType.cs

@@ -23,5 +23,10 @@ public static class AgentType
     /// Agent that cannot use external tools
     /// </summary>
     public const string Static = "static";
+
+    /// <summary>
+    /// A2A remote agent for Microsoft Agent Framework integration
+    /// </summary>
+    public const string A2ARemote = "a2a-remote";
 }
 

src/Plugins/BotSharp.Plugin.AgentFramework/AgentFrameworkPlugin.cs

@@ -0,0 +1,61 @@
+using BotSharp.Abstraction.Agents;
+using BotSharp.Abstraction.Conversations;
+using BotSharp.Abstraction.Plugins;
+using BotSharp.Abstraction.Settings;
+using BotSharp.Plugin.AgentFramework.Hooks;
+using BotSharp.Plugin.AgentFramework.Services;
+using BotSharp.Plugin.AgentFramework.Settings;
+using Microsoft.Extensions.Caching.Memory;
+using Microsoft.Extensions.Configuration;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.DependencyInjection.Extensions;
+
+namespace BotSharp.Plugin.AgentFramework;
+
+/// <summary>
+/// Plugin for integrating BotSharp with Microsoft Agent Framework (MAF) via A2A protocol
+/// </summary>
+public class AgentFrameworkPlugin : IBotSharpPlugin
+{
+    public string Id => "3F8E4B9C-7D2A-4E1F-9B3C-5A6D8E2F1C4B";
+
+    public string Name => "Microsoft Agent Framework";
+
+    public string Description => "Integrates BotSharp with Microsoft Agent Framework (MAF) using Agent2Agent (A2A) protocol based on JSON-RPC 2.0";
+
+    public string? IconUrl => "https://learn.microsoft.com/en-us/media/logos/logo-ms-social.png";
+
+    public void RegisterDI(IServiceCollection services, IConfiguration config)
+    {
+        // Register settings
+        services.AddScoped(provider =>
+        {
+            var settingService = provider.GetRequiredService<ISettingService>();
+            return settingService.Bind<AgentFrameworkSettings>("AgentFramework");
+        });
+
+        // Register HTTP client for A2A communication with timeout configuration
+        services.AddHttpClient("A2AClient", client =>
+        {
+            client.DefaultRequestHeaders.Add("User-Agent", "BotSharp-A2A-Client/1.0");
+            client.DefaultRequestHeaders.Add("Accept", "application/json");
+        })
+        .ConfigureHttpClient((sp, client) =>
+        {
+            var settings = sp.GetRequiredService<AgentFrameworkSettings>();
+            client.Timeout = TimeSpan.FromSeconds(settings.TimeoutSeconds);
+        });
+
+        // Register memory cache for agent card caching (use TryAdd to avoid conflicts)
+        services.TryAddSingleton<IMemoryCache, MemoryCache>();
+
+        // Register A2A services
+        services.AddSingleton<IA2AClientFactory, A2AClientFactory>();
+        services.AddSingleton<A2ACardResolver>();
+        services.AddScoped<IA2AAgentService, A2AAgentService>();
+
+        // Register hooks
+        services.AddScoped<IAgentHook, AgentFrameworkHook>();
+        services.AddScoped<IConversationHook, AgentFrameworkConversationHook>();
+    }
+}

src/Plugins/BotSharp.Plugin.AgentFramework/BotSharp.Plugin.AgentFramework.csproj

@@ -0,0 +1,23 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>$(TargetFramework)</TargetFramework>
+    <Nullable>enable</Nullable>
+    <LangVersion>$(LangVersion)</LangVersion>
+    <VersionPrefix>$(BotSharpVersion)</VersionPrefix>
+    <GeneratePackageOnBuild>$(GeneratePackageOnBuild)</GeneratePackageOnBuild>
+    <GenerateDocumentationFile>$(GenerateDocumentationFile)</GenerateDocumentationFile>
+    <OutputPath>$(SolutionDir)packages</OutputPath>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Refit" />
+    <PackageReference Include="Refit.HttpClientFactory" />
+    <PackageReference Include="Rougamo.Fody" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\..\Infrastructure\BotSharp.Core\BotSharp.Core.csproj" />
+  </ItemGroup>
+
+</Project>

src/Plugins/BotSharp.Plugin.AgentFramework/Examples/README.md

@@ -0,0 +1,248 @@
+# MAF Integration Examples
+
+This directory contains example configurations and usage patterns for the BotSharp MAF integration plugin.
+
+## Files
+
+- **appsettings.example.json**: Example application settings configuration
+- **agent-config.example.json**: Example agent configuration for a remote MAF agent
+- **agent-card.example.json**: Example agent card that would be returned from a MAF service
+
+## Quick Start
+
+### 1. Configure the Plugin
+
+Add the configuration to your `appsettings.json`:
+
+```json
+{
+  "AgentFramework": {
+    "Enabled": true,
+    "TimeoutSeconds": 30,
+    "PollingIntervalMs": 2000,
+    "MaxPollingAttempts": 60,
+    "AgentCardCacheDurationMinutes": 30
+  }
+}
+```
+
+### 2. Create a Remote Agent Configuration
+
+Create an agent configuration file (e.g., `agents/hr-assistant.json`):
+
+```json
+{
+  "id": "hr-assistant-remote",
+  "name": "HR Assistant (Remote)",
+  "description": "Handles employee leave requests and policy inquiries",
+  "type": "a2a-remote",
+  "templateDict": {
+    "a2a_endpoint": "https://your-maf-service.azurewebsites.net"
+  }
+}
+```
+
+### 3. Deploy MAF Service
+
+Your MAF service should expose the following endpoints:
+
+#### Agent Discovery Endpoint
+```
+GET https://your-maf-service.azurewebsites.net/.well-known/agent-card.json
+
+Response:
+{
+  "name": "HR_Assistant",
+  "description": "Handles employee leave requests...",
+  "version": "1.0.0",
+  "capabilities": ["leave_management", "policy_inquiry"]
+}
+```
+
+#### Task Execution Endpoint
+```
+POST https://your-maf-service.azurewebsites.net/a2a/tasks
+Content-Type: application/json
+
+Request (sendTask):
+{
+  "jsonrpc": "2.0",
+  "method": "sendTask",
+  "id": "unique-request-id",
+  "params": {
+    "input": "I want to book leave for next week",
+    "context": {
+      "history": [...]
+    }
+  }
+}
+
+Response:
+{
+  "jsonrpc": "2.0",
+  "id": "unique-request-id",
+  "result": {
+    "taskId": "task_123",
+    "status": "completed",
+    "output": "Your leave request has been submitted successfully."
+  }
+}
+```
+
+#### Task Status Endpoint
+```
+POST https://your-maf-service.azurewebsites.net/a2a/tasks
+Content-Type: application/json
+
+Request (getTask):
+{
+  "jsonrpc": "2.0",
+  "method": "getTask",
+  "id": "unique-request-id",
+  "params": {
+    "taskId": "task_123"
+  }
+}
+
+Response:
+{
+  "jsonrpc": "2.0",
+  "id": "unique-request-id",
+  "result": {
+    "taskId": "task_123",
+    "status": "completed",
+    "output": "Your leave request has been submitted successfully."
+  }
+}
+```
+
+## Testing
+
+### Manual Testing with curl
+
+#### Test Agent Card Discovery
+```bash
+curl https://your-maf-service.azurewebsites.net/.well-known/agent-card.json
+```
+
+#### Test Task Submission
+```bash
+curl -X POST https://your-maf-service.azurewebsites.net/a2a/tasks \
+  -H "Content-Type: application/json" \
+  -d '{
+    "jsonrpc": "2.0",
+    "method": "sendTask",
+    "id": "test-1",
+    "params": {
+      "input": "What is the leave policy?"
+    }
+  }'
+```
+
+#### Test Task Status
+```bash
+curl -X POST https://your-maf-service.azurewebsites.net/a2a/tasks \
+  -H "Content-Type: application/json" \
+  -d '{
+    "jsonrpc": "2.0",
+    "method": "getTask",
+    "id": "test-2",
+    "params": {
+      "taskId": "task_123"
+    }
+  }'
+```
+
+## Integration Flow
+
+1. **Agent Loading**: When BotSharp loads an agent with type "a2a-remote":
+   - The plugin fetches the agent card from `/.well-known/agent-card.json`
+   - Updates the agent description for routing purposes
+   - Caches the agent card metadata
+
+2. **Message Routing**: When a user message is routed to an A2A agent:
+   - The conversation hook intercepts the message
+   - Converts conversation history to A2A format
+   - Submits task via `sendTask` method
+
+3. **Response Handling**:
+   - If task completes immediately, returns the output
+   - If task is queued/running, polls using `getTask` method
+   - Returns the final output to the user
+
+## Troubleshooting
+
+### Agent not loading
+- Check that `a2a_endpoint` is set in agent's `templateDict`
+- Verify the endpoint is accessible and returns a valid agent card
+- Check logs for HTTP errors or network issues
+
+### Messages not being intercepted
+- Ensure `AgentFramework.Enabled` is set to `true`
+- Verify agent `type` is set to `"a2a-remote"`
+- Check that the agent is not disabled
+
+### Polling timeouts
+- Increase `MaxPollingAttempts` in settings
+- Verify the MAF service is returning task status updates
+- Check network latency between BotSharp and MAF service
+
+## Development Notes
+
+### Creating a Mock MAF Service
+
+For development and testing, you can create a simple mock MAF service using ASP.NET Core:
+
+```csharp
+// Program.cs
+var builder = WebApplication.CreateBuilder(args);
+var app = builder.Build();
+
+// Agent Card endpoint
+app.MapGet("/.well-known/agent-card.json", () => 
+{
+    return Results.Json(new
+    {
+        name = "Test_Agent",
+        description = "Test agent for development",
+        version = "1.0.0",
+        capabilities = new[] { "test" }
+    });
+});
+
+// Task endpoint
+app.MapPost("/a2a/tasks", async (HttpContext context) =>
+{
+    var request = await context.Request.ReadFromJsonAsync<JsonDocument>();
+    var method = request.RootElement.GetProperty("method").GetString();
+
+    if (method == "sendTask")
+    {
+        return Results.Json(new
+        {
+            jsonrpc = "2.0",
+            id = request.RootElement.GetProperty("id").GetString(),
+            result = new
+            {
+                taskId = Guid.NewGuid().ToString(),
+                status = "completed",
+                output = "Mock response from MAF service"
+            }
+        });
+    }
+
+    return Results.BadRequest();
+});
+
+app.Run();
+```
+
+### Testing with Postman
+
+Import the example requests from this directory into Postman to test your MAF service endpoints before integrating with BotSharp.
+
+## Additional Resources
+
+- [BotSharp Documentation](https://github.com/Ai4c-AI/BotSharp)
+- [Microsoft Agent Framework](https://github.com/microsoft/agent-framework)
+- [JSON-RPC 2.0 Specification](https://www.jsonrpc.org/specification)

src/Plugins/BotSharp.Plugin.AgentFramework/Examples/agent-card.example.json

@@ -0,0 +1,15 @@
+{
+  "name": "HR_Assistant",
+  "description": "Handles employee leave requests, policy inquiries, and HR-related questions. Can check leave balances, book leave, and answer HR policy questions.",
+  "version": "1.0.0",
+  "capabilities": [
+    "leave_management",
+    "policy_inquiry",
+    "employee_information"
+  ],
+  "metadata": {
+    "author": "HR Team",
+    "category": "Human Resources",
+    "supported_languages": ["en", "zh-CN"]
+  }
+}

src/Plugins/BotSharp.Plugin.AgentFramework/Examples/agent-config.example.json

@@ -0,0 +1,16 @@
+{
+  "id": "hr-assistant-remote",
+  "name": "HR Assistant (Remote)",
+  "description": "Handles employee leave requests and policy inquiries via remote MAF service",
+  "type": "a2a-remote",
+  "isPublic": true,
+  "disabled": false,
+  "profiles": ["maf_integration"],
+  "llmConfig": {
+    "provider": "openai",
+    "model": "gpt-4"
+  },
+  "templateDict": {
+    "a2a_endpoint": "https://your-maf-service.azurewebsites.net"
+  }
+}

src/Plugins/BotSharp.Plugin.AgentFramework/Examples/appsettings.example.json

@@ -0,0 +1,9 @@
+{
+  "AgentFramework": {
+    "Enabled": true,
+    "TimeoutSeconds": 30,
+    "PollingIntervalMs": 2000,
+    "MaxPollingAttempts": 60,
+    "AgentCardCacheDurationMinutes": 30
+  }
+}