OTel metrics for Microprofile Telemetry 2.0

[brunobat]

Provides OpenTelemetry metrics according to https://github.com/eclipse/microprofile-telemetry/blob/2.0/spec/src/main/asciidoc/metrics.adoc

[quarkus-bot]

/cc @radcortez (opentelemetry)

[brunobat]

Will include the TCK updates as well... Set to draft until then.

[github-actions]

🙈 The PR is closed and the preview is expired.

[Ladicek]

Off topic (but not all that much I guess): are you planning to support MetricsCapabilityBuildItem? (And the related SPIs too, probably?)

[brunobat]

Off topic (but not all that much I guess): are you planning to support MetricsCapabilityBuildItem? (And the related SPIs too, probably?)

I'll decide that after evaluating the future Micrometer to OpenTelemetry bridge.
It it goes well, there might be no more automatic metrics for OTel.

[brunobat]

#43752 is needed for the native image tests to pass because it includes an OTel side instrumentation fix.

[brunobat]

There are 2 implementations for this failing metric ThreadCountMetric. One for Java 17:
io.opentelemetry.instrumentation.runtimemetrics.java17.internal.threads.ThreadCountHandler#METRIC_DESCRIPTION
Another one for Java 8:
https://github.com/open-telemetry/opentelemetry-java-instrumentation/blob/745d880c06676a28d75c5567aa7bd5ad68c5da2d/instrumentation/runtime-telemetry/runtime-telemetry-java8/library/src/main/java/io/opentelemetry/instrumentation/runtimemetrics/java8/Threads.java#L69

They both use different descriptions and the TCK requires the Java 8 flavour:
https://github.com/eclipse/microprofile-telemetry/blob/88735b74308d123a324b66cc9c4a132f980cb541/tck/metrics/src/main/java/org/eclipse/microprofile/telemetry/metrics/tck/jvm/JvmThreadTest.java#L59

[gsmet]

The changes look good to me except for some minor nitpicking in the doc - but I might have misunderstood the sentence.

As for the failing test, should we raise an issue in the TCK and for now ignore this test?

[brunobat]

Created eclipse/microprofile-telemetry#241

[radcortez]

Created eclipse/microprofile-telemetry#241

You can also exclude the failing test (because of the challenge) so we can proceed with the PR. Check:
https://github.com/smallrye/smallrye-opentelemetry/blob/a750353e55ccede3fe498bbc693be21621dac7a5/testsuite/tck/pom.xml#L97-L105

[quarkus-bot]

Status for workflow Quarkus Documentation CI

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✅ The latest workflow run for the pull request has completed successfully.

It should be safe to merge provided you have a look at the other checks in the summary.

Warning

There are other workflow runs running, you probably need to wait for their status before merging.

[quarkus-bot]

Status for workflow Quarkus CI

This is the status report for running Quarkus CI on commit 7853d67.

✅ The latest workflow run for the pull request has completed successfully.

It should be safe to merge provided you have a look at the other checks in the summary.

You can consult the Develocity build scans.

[gsmet]

@radcortez I will let you review this one. I could be convinced to shoe it in 3.16.0 post CR1 if we think it has high value for 3.16.

[radcortez]

We want this for MP 7.0 compatibility. Let me check what is the state of the missing pieces. If the other pieces are not ready, we don't need to rush this.