Adding common tags to all metrics

[stefano-salmaso]

Hi all!
We are using opentelemetry java-agent and we need to add some common tags to all the metrics generated by our application.
The value is fixed and defined at startup.
We are able to add common tags to the Micrometer MeterRegistry.. but we need the same tags also to the metric generated directly by the auto instrumentation, like Tomcat metrics.
We tried in several way but with no luck!
Adding metrics using the collector is not an option for us.

Any way to do that?
Thanks

[laurit]

You could try using a resource attribute https://github.com/open-telemetry/opentelemetry-java/blob/main/sdk-extensions/autoconfigure/README.md#opentelemetry-resource

[stefano-salmaso]

Hi @laurit
I tried... but the resources added are not present as tags into the metrics!

[mateuszrzeszutek]

Hey @stefano-salmaso ,

Are you perhaps using the prometheus metrics exporter?

[stefano-salmaso]

I tried both with prometheus and otlp (to the collector) but again... nothing I added with otel.resource.attributes is present into metrics

[mateuszrzeszutek]

OTLP definitely captures all resource attributes -- if you're not seeing them in your chosen observability backend it may be that it does not support resource attributes.

The Prometheus exporter unfortunately has a limited support for resource attributes, see open-telemetry/opentelemetry-java#5529

[stefano-salmaso]

Hi @mateuszrzeszutek
with OTLP exporter I have all resource attributes as tags into metrics. My point was the resource_to_telemetry_conversion with false in the collector. Changing it everything is working!
Thanks!