FAI Aspire Orchestration

Configures .NET Aspire to compose multi-container AI applications with automatic service discovery, environment variable injection, OpenTelemetry pipeline, and local Azure emulators. Solves the dev-setup friction where developers spend a day configuring connection strings that Aspire injects automatically.

When to Invoke

Workflow

Step 1 — AppHost Setup

// AppHost/Program.cs -- the orchestration entry point
var builder = DistributedApplication.CreateBuilder(args);

// Backing services -- Aspire manages lifecycle and connection strings
var redis      = builder.AddRedis("redis-cache");
var cosmos     = builder.AddAzureCosmosDB("cosmos").AddDatabase("chatdb");
var storage    = builder.AddAzureStorage("storage").AddBlobs("documents");
var servicebus = builder.AddAzureServiceBus("servicebus").AddQueue("embedding-jobs");

// AI service endpoints from environment (Managed Identity in prod, env vars locally)
var aoai   = builder.AddConnectionString("aoai-endpoint");
var search = builder.AddConnectionString("search-endpoint");

// Application projects -- Aspire injects all connection strings automatically
var api = builder.AddProject<Projects.Api>("api")
    .WithReference(redis)
    .WithReference(cosmos)
    .WithReference(aoai)
    .WithReference(search)
    .WithReference(servicebus);

var worker = builder.AddProject<Projects.EmbeddingWorker>("worker")
    .WithReference(storage)
    .WithReference(servicebus)
    .WithReference(aoai);

builder.Build().Run();

Step 2 — Service Discovery in Application Code

// api/Program.cs -- inject discovered endpoints, no hardcoded URLs
var builder = WebApplication.CreateBuilder(args);
builder.AddServiceDefaults();   // Aspire extension: health, OTEL, discovery

// Redis -- name matches the AppHost reference name
builder.AddRedisDistributedCache("redis-cache");

// Cosmos DB -- connection string injected from AppHost
builder.AddAzureCosmosClient("cosmos");

// HTTP client to worker -- resolved via Aspire service discovery
builder.Services.AddHttpClient<EmbeddingClient>(c =>
    c.BaseAddress = new Uri("https+http://worker"));   // Aspire resolves this at runtime

var app = builder.Build();
app.MapDefaultEndpoints();   // /health/live, /health/ready
app.Run();

Step 3 — OpenTelemetry Pipeline

// ServiceDefaults/Extensions.cs -- generated by Aspire, customise here
public static IHostApplicationBuilder AddServiceDefaults(
    this IHostApplicationBuilder builder)
{
    builder.ConfigureOpenTelemetry();
    builder.AddDefaultHealthChecks();
    builder.Services.AddServiceDiscovery();
    builder.Services.ConfigureHttpClientDefaults(http =>
    {
        http.AddStandardResilienceHandler();   // Retry + circuit breaker
        http.AddServiceDiscovery();
    });
    return builder;
}

// OpenTelemetry -- traces, metrics, logs to OTEL collector
builder.Services.AddOpenTelemetry()
    .WithTracing(t => t
        .AddAspNetCoreInstrumentation()
        .AddHttpClientInstrumentation()
        .AddRedisInstrumentation()
        .AddOtlpExporter())
    .WithMetrics(m => m
        .AddAspNetCoreInstrumentation()
        .AddRuntimeInstrumentation()
        .AddOtlpExporter());

Step 4 — Local Azure Emulators

// AppHost -- use emulators locally, real Azure services in CI/prod
var storage = builder.AddAzureStorage("storage")
    .RunAsEmulator(cfg => cfg
        .WithBlobPort(10000)
        .WithQueuePort(10001));

var servicebus = builder.AddAzureServiceBus("servicebus")
    .RunAsEmulator();   // Uses the Service Bus emulator Docker image

var cosmos = builder.AddAzureCosmosDB("cosmos")
    .RunAsEmulator(cfg => cfg.WithGatewayPort(8081));

Step 5 — Azure Container Apps Deployment

# Deploy Aspire manifest to Azure Container Apps
azd init --template aspire
azd env new prod
azd env set AZURE_SUBSCRIPTION_ID <sub>
azd env set AZURE_LOCATION eastus2
azd up   # Provisions ACA environment, deploys all projects

# Verify running services
az containerapp list --resource-group rg-aspire-prod \
  --query "[].{name:name, url:properties.configuration.ingress.fqdn}" \
  --output table

Aspire Developer Dashboard

Aspire provides a local developer dashboard at http://localhost:15888:

Service Discovery Reference

WAF Alignment

Compatible Solution Plays

• Play 07 — Multi-Agent Service (.NET agent orchestration)
• Play 20 — Real-Time Analytics (event streaming pipeline)
• Play 37 — DevOps AI (CI/CD pipeline components)

Notes

• Aspire requires .NET 8+ and Docker Desktop (or Podman) for container management
• AddServiceDefaults() must be called as the first extension in every app project
• Use RunAsEmulator() for local dev; emulators are not started in CI unless explicitly configured
• WithReference() on a project creates both the connection string env var and a health dependency