OpenTelemetry counter

[cthiebault]

Hello,

I'm new to OpenTelemetry, and I'm trying to create a simple counter to send metrics to Datadog.

Here is my Kotlin code:

import io.opentelemetry.api.OpenTelemetry
import io.opentelemetry.api.metrics.LongCounter
import jakarta.enterprise.context.ApplicationScoped
import jakarta.inject.Inject

@ApplicationScoped
class Metrics @Inject constructor(private val openTelemetry: OpenTelemetry) {

  fun incrementCounter() {
    val counter: LongCounter = openTelemetry.getMeter("my-metrics")
      .counterBuilder("counter")
      .build()
    counter.add(1)
  }
}

And the Quarkus configuration:

quarkus:
  otel:
    sdk:
      disabled: false
    exporter:
      otlp:
        traces:
          endpoint: ${OTEL_EXPORTER_OTLP_ENDPOINT}

When I run it, the counter is an instance of io.opentelemetry.api.metrics.DefaultMeter$NoopLongCounter, so of course I
don't get any metrics in Datadog :(

It seems that the MeterProvider is a io.opentelemetry.api.metrics.DefaultMeterProvider$NoopMeterBuilder and I don't
know how to configure Quarkus to not use a NOOP MeterProvider.

Any ideas?

Thanks in advance for your help :)

[quarkus-bot[bot]]

/cc @brunobat (opentelemetry), @evanchooly (kotlin), @geoand (kotlin), @radcortez (opentelemetry)

[brunobat]

Quarkus doesn't support Micrometer metrics yet.
You can use Micrometer metrics and the quarkiverse OTLP registry to send the output in an OTel compatible format.

[cthiebault]

Ah ok :-)
Thanks for your answer! I will have a look to the quarkiverse stuff!