Update OTLP Metrics Exporter with latest Metrics SDK

[legendecas]

After the major refactoring of Metrics SDK, we should update the OTLP Metrics Exporter to adopt the changes.

• Refactor metrics export data model to match proto #2775

[rauno56]

What kind of discussion this and #2773 requires?

[legendecas]

@rauno56 This is a tracker issue like #2574 to track the implementation progress of the OTLP metrics exporter. Any topics about the implementations are welcome.

[dyladan]

This will depend on #2775

[mplachter]

Any update on this as #2775 seems to be closed now. Seems this no longer works with any OTEL Collector past 0.42.0

[dyladan]

We are approaching a useable release of the metrics rewrite and this is one of the last things that will be required before we can release an alpha so I expect it to be on deck soon

[pichlermarc]

I'd like to 'pick this one up if nobody is working on this yet. 🙂

[pichlermarc]

After #2871 has merged, the exporters still need to be updated to use the otlp-transformer package for this issue to be actually done. They will be in a usable state, but they it will be quite outdated on the OTLP side.

I will do that in a follow-up PR to unblock everyone who is currently waiting on #2871.

[pichlermarc]

Since #2871 technically updates the OTLP Metrics Exporters to use the latest SDK. Should I create follow up issues to track changes that are still needed in the exporters? 🤔

I think there a a few steps left to get all exporters into a more manageable state:

• refactor: Move OTLPExporter*Base from exporter-trace-otlp-http to a new package otlp-exporter-base so that the metrics exporters do not need to depend on the trace exporters anymore. (I would start working on that right away)
• feature/fix: Update metrics exporters to newer proto version (which will also fix opentelemetry/exporter-metrics-otlp-http Does not send metrics to collector (with last collector version 0.40.0) #2675)
  • also make the metrics exporter use the otlp-transformer package to reduce duplicated code.
• feature/fix: Update trace exporters to newer proto version
  • also make the trace exporter use the otlp-transformer package to reduce duplicated code.

[legendecas]

@pichlermarc you can track all of the items that need to be done by listing them in the OP. Or if you prefer tracking them in separate issues, I'm fine with either way.

[pichlermarc]

Thanks! I created a single issue with all of these items on it (#2886) 🙂

[pichlermarc]

This issue is done and can be closed 🙂

[legendecas]

Well done @pichlermarc 🎉