Tracing / OpenTelemetry

[Juandavi1]

Hi ! Do you know how to implement distributed tracing with slim ?

[zarusz]

Hi @Juandavi1 could you please elaborate?

[Juandavi1]

Hi ! We are working with OpenTelemetry and we need to create the spans when consume and publish events. For example en Go we have otelsarama to do it ! There is an option to add an interceptor to add this functionality ?

[zarusz]

Now it is more clear, thanks. I assume you are using Kafka transport, is that correct?

There is nothing available out of box, ideally tracing/metrics/instrumentation could be done as a producer/consumer interceptors which would add the necessary spans (or other instrumentation) to the consumers or producer. The interceptor implementation could use one of these:

• System.Diagnostics as the facade
• or OpenTelemetry directly

Regarding otelsarama I do not know it, but it looks like it's meant for Go client application. Not sure if this could be used in .NET.

I am happy to review a contribution/PR for a tracing plugin to make this part of SMB, or provide help.

[Juandavi1]

Hi ! Awesome !
I was wondering whether there's a global interceptor 🤔
The currently interface requires a message type 🥲

[zarusz]

Actually, you can make a generic message interceptor as explained here
https://github.com/zarusz/SlimMessageBus/blob/master/docs/intro.md#generic-interceptors

You can see this working for the outbox plugin
https://github.com/zarusz/SlimMessageBus/blob/master/src/SlimMessageBus.Host.Outbox/Configuration/ServiceCollectionExtensions.cs#L12

[Juandavi1]

I will try it! Thank you very much!

[zarusz]

The feature should be generating instrumentation using:
https://www.nuget.org/packages/System.Diagnostics.DiagnosticSource
https://learn.microsoft.com/en-us/dotnet/core/diagnostics/diagnosticsource-diagnosticlistener

When the extension is built it needs to follow this:
https://github.com/open-telemetry/opentelemetry-dotnet/blob/main/docs/trace/extending-the-sdk/README.md#instrumentation-library