feat(metrics): add opentelemetry support

[ahkui]

Signed-off-by: ahkui ahkui@outlook.com

#574

Motivation / Background

Implement metrics collection using the OpenTelemetry MeterProvider

Detail

Implement metrics collection using the OpenTelemetry MeterProvider

Alternative approaches considered (if applicable)

Checklist

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[ahkui]

Hi @roblaszczak and @m110,

Could you please help review this PR when you have a moment?

Thanks!

[roblaszczak]

We had this issue with OpenTelemtry in many projects: open-telemetry/opentelemetry-go#4476

To avoid that it would be good to move OpenTelemetry implementation to a separate package, with a separate go.mod. So the main go.mod won't be affected.

I would moving those changes to a separate components/opentelemetry package.

Do you feel you'll have time for that @ahkui? Let us know!

[ahkui]

We had this issue with OpenTelemtry in many projects: open-telemetry/opentelemetry-go#4476

To avoid that it would be good to move OpenTelemetry implementation to a separate package, with a separate go.mod. So the main go.mod won't be affected.

I would moving those changes to a separate components/opentelemetry package.

Do you feel you'll have time for that @ahkui? Let us know!

@roblaszczak yes, i can handle that

the new pkg i will move to components/metrics/opentelemetry, do you have other suggestion for the location ?

[roblaszczak]

We had this issue with OpenTelemtry in many projects: open-telemetry/opentelemetry-go#4476
To avoid that it would be good to move OpenTelemetry implementation to a separate package, with a separate go.mod. So the main go.mod won't be affected.
I would moving those changes to a separate components/opentelemetry package.
Do you feel you'll have time for that @ahkui? Let us know!

@roblaszczak yes, i can handle that

the new pkg i will move to components/metrics/opentelemetry, do you have other suggestion for the location ?

Hey, I discussed it with @m110 and since it looks orthogonal to the metrics package we can keep it flat (keeping it in sub-directory would suggest that it depends on metrics).

So I would suggest components/opentelemetry. It will be also easier to find :-)

[Thorleon]

Hey @ahkui and @roblaszczak, I would love to have OTEL metrics in Watermill, do you need any help to finalize this Pull Request?