gh-lucaspimentel-claude-code-plugins-plugins-dd-trace-dotnet/commands/create-integration.md

description

description
Create a new auto-instrumentation integration

Create a new auto-instrumentation integration for the Datadog .NET tracer.

Follow these steps:

1. Gather requirements:

   • Target library name and NuGet package
   • Supported version range
   • Methods to instrument (assembly, type, method signatures)
   • Integration category (e.g., HTTP, Database, Messaging, etc.)

2. Create integration class:

   • Location: tracer/src/Datadog.Trace/ClrProfiler/AutoInstrumentation/<Area>/<Integration>.cs
   • Add [InstrumentMethod] attribute with:
     • AssemblyName: Target assembly
     • TypeName: Fully qualified type name
     • MethodName: Method to instrument
     • ReturnTypeName: Method return type
     • ParameterTypeNames: Array of parameter types
     • MinimumVersion and MaximumVersion: Version range
     • IntegrationName: Unique integration identifier
   • Implement OnMethodBegin (for method entry)
   • Implement OnMethodEnd or OnAsyncMethodEnd (for method exit)

3. Use duck typing for third-party types:

   • Define interface with required properties/methods
   • Use where TTarget : IMyInterface, IDuckType constraint
   • Or use target.DuckCast<IMyInterface>() for runtime casting

4. Add integration tests:

   • Location: tracer/test/Datadog.Trace.ClrProfiler.IntegrationTests/<Area>/
   • Create sample application: tracer/test/test-applications/integrations/<Library>/
   • Test multiple library versions (package_versions.props)
   • Verify spans are created with correct tags

5. Generate boilerplate:

   • Run: ./tracer/build.ps1 RunInstrumentationGenerator

6. Update documentation:

   • Add integration to supported libraries list if needed

Reference files:

• docs/development/AutomaticInstrumentation.md - Complete integration guide
• docs/development/DuckTyping.md - Duck typing patterns
• tracer/src/Datadog.Trace/ClrProfiler/AutoInstrumentation/ - Existing integrations

After creating:

• Run the instrumentation generator
• Build the tracer
• Run integration tests
• Verify spans in test output