Exemplars in HTTP server metrics

[akselleirv]

Hello!

I'm converting OpenTelemetry metrics to Prometheus metrics using Grafana Agent, and one of the metrics I'm using is http_server_duration_milliseconds_bucket. I've checked that Grafana Agent supports converting exemplars, so it seems that the library instrumentation does not have any exemplars.

Is this the case? If so, would exemplars be added in the future?

[trask]

I believe exemplars for http server duration metric should be working, see tests and prior issues: https://github.com/search?q=repo%3Aopen-telemetry%2Fopentelemetry-java-instrumentation%20exemplars&type=code

[akselleirv]

They do have exemplars when I test locally with:

java -javaagent:opentelemetry-javaagent.jar -Dotel.metrics.exporter=prometheus -jar target/my-app.jar

And use curl to get the exemplars:

curl -H 'Accept: application/openmetrics-text' http://localhost:9464

So it might be that the Grafana Agent is the problem.