.NET: [Durable Agents] Reliable streaming sample (#2942)

* .NET: [Durable Agents] Reliable streaming sample * Add automated validation for new sample * Address Copilot PR feedback
2026-06-16 21:04:09 +08:00 · 2025-12-19 23:43:36 +00:00
parent 3b77192ad0
commit 0e152a0e33
13 changed files with 1344 additions and 0 deletions
@@ -0,0 +1,100 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+// This sample demonstrates how to implement reliable streaming for durable agents using Redis Streams.
+// It exposes two HTTP endpoints:
+// 1. Create - Starts an agent run and streams responses back via Server-Sent Events (SSE)
+// 2. Stream - Resumes a stream from a specific cursor position, enabling reliable message delivery
+//
+// This pattern is inspired by OpenAI's background mode for the Responses API, which allows clients
+// to disconnect and reconnect to ongoing agent responses without losing messages.
+
+using Azure;
+using Azure.AI.OpenAI;
+using Azure.Identity;
+using Microsoft.Agents.AI.DurableTask;
+using Microsoft.Agents.AI.Hosting.AzureFunctions;
+using Microsoft.Azure.Functions.Worker.Builder;
+using Microsoft.Extensions.AI;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Hosting;
+using OpenAI.Chat;
+using ReliableStreaming;
+using StackExchange.Redis;
+
+// Get the Azure OpenAI endpoint and deployment name from environment variables.
+string endpoint = Environment.GetEnvironmentVariable("AZURE_OPENAI_ENDPOINT")
+    ?? throw new InvalidOperationException("AZURE_OPENAI_ENDPOINT is not set.");
+string deploymentName = Environment.GetEnvironmentVariable("AZURE_OPENAI_DEPLOYMENT")
+    ?? throw new InvalidOperationException("AZURE_OPENAI_DEPLOYMENT is not set.");
+
+// Get Redis connection string from environment variable.
+string redisConnectionString = Environment.GetEnvironmentVariable("REDIS_CONNECTION_STRING")
+    ?? "localhost:6379";
+
+// Get the Redis stream TTL from environment variable (default: 10 minutes).
+int redisStreamTtlMinutes = int.TryParse(
+    Environment.GetEnvironmentVariable("REDIS_STREAM_TTL_MINUTES"),
+    out int ttlMinutes) ? ttlMinutes : 10;
+
+// Use Azure Key Credential if provided, otherwise use Azure CLI Credential.
+string? azureOpenAiKey = System.Environment.GetEnvironmentVariable("AZURE_OPENAI_KEY");
+AzureOpenAIClient client = !string.IsNullOrEmpty(azureOpenAiKey)
+    ? new AzureOpenAIClient(new Uri(endpoint), new AzureKeyCredential(azureOpenAiKey))
+    : new AzureOpenAIClient(new Uri(endpoint), new AzureCliCredential());
+
+// Travel Planner agent instructions - designed to produce longer responses for demonstrating streaming.
+const string TravelPlannerName = "TravelPlanner";
+const string TravelPlannerInstructions =
+    """
+    You are an expert travel planner who creates detailed, personalized travel itineraries.
+    When asked to plan a trip, you should:
+    1. Create a comprehensive day-by-day itinerary
+    2. Include specific recommendations for activities, restaurants, and attractions
+    3. Provide practical tips for each destination
+    4. Consider weather and local events when making recommendations
+    5. Include estimated times and logistics between activities
+    
+    Always use the available tools to get current weather forecasts and local events
+    for the destination to make your recommendations more relevant and timely.
+    
+    Format your response with clear headings for each day and include emoji icons
+    to make the itinerary easy to scan and visually appealing.
+    """;
+
+// Configure the function app to host the AI agent.
+FunctionsApplicationBuilder builder = FunctionsApplication
+    .CreateBuilder(args)
+    .ConfigureFunctionsWebApplication()
+    .ConfigureDurableAgents(options =>
+    {
+        // Define the Travel Planner agent with tools for weather and events
+        options.AddAIAgentFactory(TravelPlannerName, sp =>
+        {
+            return client.GetChatClient(deploymentName).CreateAIAgent(
+                instructions: TravelPlannerInstructions,
+                name: TravelPlannerName,
+                services: sp,
+                tools: [
+                    AIFunctionFactory.Create(TravelTools.GetWeatherForecast),
+                    AIFunctionFactory.Create(TravelTools.GetLocalEvents),
+                ]);
+        });
+    });
+
+// Register Redis connection as a singleton
+builder.Services.AddSingleton<IConnectionMultiplexer>(_ =>
+    ConnectionMultiplexer.Connect(redisConnectionString));
+
+// Register the Redis stream response handler - this captures agent responses
+// and publishes them to Redis Streams for reliable delivery.
+// Registered as both the concrete type (for FunctionTriggers) and the interface (for the agent framework).
+builder.Services.AddSingleton(sp =>
+    new RedisStreamResponseHandler(
+        sp.GetRequiredService<IConnectionMultiplexer>(),
+        TimeSpan.FromMinutes(redisStreamTtlMinutes)));
+builder.Services.AddSingleton<IAgentResponseHandler>(sp =>
+    sp.GetRequiredService<RedisStreamResponseHandler>());
+
+using IHost app = builder.Build();
+
+app.Run();