Kielek
commented
1 year ago By default ASP.NET Core is using tracecontext propagator to inject/extract information about span context.
Your DummyWebApp does not have any any telemetry listener, but AspNetCore Activities are created and marked as non-registered. That information is propagated by http headers in the request to the DummyAPI.
What is more OpenTelemetry by default is using new ParentBasedSampler(new AlwaysOnSampler()). That means if you do not have parent based information - sample always. If you have it, respect sampling decision from the parent.
It can be overriten by in your DummyAPI package.
builder.Services
.AddOpenTelemetry()
.WithTracing(b => b
.SetSampler(new AlwaysOnSampler())
.AddAspNetCoreInstrumentation()
.AddConsoleExporter())
.StartWithHost();
After changes, call from DummyWebApp to DummyAPI (Activity.ParentSpanId is recorded) Activity.TraceId: 7aae8aede8340bdb938494b67f3b8f90 Activity.SpanId: 0bbf4f827511a35b Activity.TraceFlags: Recorded Activity.ParentSpanId: 3552debb27e61051 Activity.ActivitySourceName: OpenTelemetry.Instrumentation.AspNetCore Activity.DisplayName: WeatherForecast Activity.Kind: Server Activity.StartTime: 2023-01-12T06:15:56.8224144Z Activity.Duration: 00:00:00.0235171 Activity.Tags: net.host.name: localhost net.host.port: 7077 http.method: GET http.scheme: https http.target: /WeatherForecast http.url: https://localhost:7077/WeatherForecast http.flavor: 1.1 http.route: WeatherForecast http.status_code: 200 Resource associated with Activity: service.name: unknown_service:DummyAPI
After changes, call from broswer/console app to DummyAPI (Activity.ParentSpanId is not available) Activity.TraceId: 98ba9b17b1aac2c344ad49615fe8db95 Activity.SpanId: 7978f2606e469f39 Activity.TraceFlags: Recorded Activity.ActivitySourceName: OpenTelemetry.Instrumentation.AspNetCore Activity.DisplayName: WeatherForecast Activity.Kind: Server Activity.StartTime: 2023-01-12T06:16:00.8129651Z Activity.Duration: 00:00:00.0212744 Activity.Tags: net.host.name: localhost net.host.port: 7077 http.method: GET http.scheme: https http.target: /WeatherForecast http.url: https://localhost:7077/WeatherForecast http.flavor: 2.0 http.user_agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/109.0.0.0 Safari/537.36 http.route: WeatherForecast http.status_code: 200 Resource associated with Activity: service.name: unknown_service:DummyAPI
I would say, that it is not a bug, rather a feature.
gfournierflinks
Bug Report
Symptom
Describe the bug In the context where OpenTelemetry is configure to add AspNetCore Instrumentation, if another web app is making a server to server call to the traced API, a trace is not generated. See Steps to reproduce for all the details.
I followed the instructions here https://github.com/open-telemetry/opentelemetry-dotnet/blob/main/src/OpenTelemetry.Instrumentation.AspNetCore/README.md
Expected behavior All traces should be generated
Runtime environment (please complete the following information):
Reproduce
Steps to reproduce the behavior:
I join the code of a very simple API called DummyAPI (see zip files attached). The solution contains 3 projects:
The dummy API uses the following dependencies:
The DummyAPI is configured as such in the Program.cs:
The only endpoint of the dummy API is a GET /WeatherForecast
The API can we called in 3 different ways :
When testing from the browser, a trace is exported to the console. When testing from the ConsoleApp, a trace is exported to the console. However, when testing with the DummyWebApp, a trace is NOT exported to the console
Inspecting the System.Diagnostics.Activity.Current when calling via the DummyWebApp, I see this:
Comparing when It's called from the browser:
In the case of calling the DummyAPI via the DummyWebApp, the System.Diagnostics.Activity.Source doesn't seem to be set properly:
Compared to when the DummyAPI is called via the browser:
Am I missing something? DummyAPI.zip