Aspire Service Defaults

When to Use This Skill

Use this skill when:

• Building Aspire-based distributed applications
• Need consistent observability (logging, tracing, metrics) across services
• Want shared health check configuration
• Configuring HttpClient resilience and service discovery

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What is ServiceDefaults?

ServiceDefaults is a shared project that provides common configuration for all services in an Aspire application:

• OpenTelemetry - Logging, tracing, and metrics
• Health Checks - Readiness and liveness endpoints
• Service Discovery - Automatic service resolution
• HTTP Resilience - Retry and circuit breaker policies

Every service references this project and calls AddServiceDefaults().

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Project Structure

src/
  MyApp.ServiceDefaults/
    Extensions.cs
    MyApp.ServiceDefaults.csproj
  MyApp.Api/
    Program.cs  # Calls AddServiceDefaults()
  MyApp.Worker/
    Program.cs  # Calls AddServiceDefaults()
  MyApp.AppHost/
    Program.cs

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ServiceDefaults Project

Project File

<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <TargetFramework>net9.0</TargetFramework>
    <IsAspireSharedProject>true</IsAspireSharedProject>
  </PropertyGroup>

  <ItemGroup>
    <FrameworkReference Include="Microsoft.AspNetCore.App" />
    <PackageReference Include="Microsoft.Extensions.Http.Resilience" />
    <PackageReference Include="Microsoft.Extensions.ServiceDiscovery" />
    <PackageReference Include="OpenTelemetry.Exporter.OpenTelemetryProtocol" />
    <PackageReference Include="OpenTelemetry.Extensions.Hosting" />
    <PackageReference Include="OpenTelemetry.Instrumentation.AspNetCore" />
    <PackageReference Include="OpenTelemetry.Instrumentation.Http" />
    <PackageReference Include="OpenTelemetry.Instrumentation.Runtime" />
  </ItemGroup>
</Project>

Extensions.cs