drewby/dapr-http-binding-testapp-csharp

Simple ASP.NET core application to test tracing with a Dapr HTTP Binding.

dapr-http-binding-testapp-csharp

Simple ASP.NET core application to test tracing with an HTTP Binding.

Current versions of the Dapr HTTP Binding to not pass traceparent and tracestate to the HTTP endpoint.

I'm using this app to verify code changes to the HTTP Binding to support trace header propogation.

The devcontainer includes a self-hosted instance of Dapr. If you do not use the devcontainer, you will need to install your own copy of the Dapr cli and run dapr init (with the -s for self-hosting).

To run the app with dapr, execute ./runwithdapr.sh.

Or run the command directly:

dapr run --app-id http-test --components-path ./components/ --config ./config/config.yaml --app-port 5000 -H 3500 -- dotnet run --project .

In a different terminal, send a request to the app using curl:

curl http://localhost:5000/Send

This will generate a response similar to:

Sent Traceparent: 00-39fa28e206037ae76349dd0154aec9db-f446d05a9b6fa499-00
Received Traceparent: 00-39fa28e206037ae76349dd0154aec9db-07e891d91fb093ee-01, Tracestate: 

We want to see the service return the return the same traceid but a different spanid (representing the span from daprd). Note that in current versions of Dpar (~v1.9) the HTTP Binding does not propogate these headers. You'll need a build that includes the propogation logic (likely v1.10).

Traceparent format: version - traceid - spanid - traceflags

What it does

[ GET /send ] --> [ DAPR Binding ] --> [ POST /receive ]

The /send endpoint creates a request and posts it to the daprd sidecar which is configured with an HTTP Binding. The request includes a Traceparent header assigned the value of System.Diagnostics.Activity.Current.Id

The HTTP binding points back at localhost and the request we send uses the /receive endpoint. If working correctly, Dapr will for include a new Traceparent that includes the traceid from our request and a new spanid.