Is it possible to add attributes to "instrumentation scope"?

[tigrannajaryan]

This OTEP proposed to add attributes to instrumentation scope.

This issue is a question for the maintainers of this repo: are we able to do this in a non-breaking manner and without significant performance impact?

[jack-berg]

Yes, I believe so. @anuraaga / @jkwatson I imagine scope attributes would be settable on MeterBuilder / TracerBuilder / LogEmitterBuilder via a new method setAttributes(Attributes). Attributes will default to empty. When ComponentRegistry#get is called to obtain a meter / tracer / logemitter, it will have to evaluate InstrumentationScopeInfo equality with attributes, in addition to the scope name, version, and schema URL.

In most cases attributes will be empty and the addition of attributes to InstrumentationScopeInfo will have minimal performance impact. In cases where attributes are not empty, performance will dictated by the performance of Attributes.equals() which I understand is reasonably good.

[jkwatson]

Yep. The builders are the place to add it to the API, for sure. In the SDK, we'll need to add some sort of creational method for InstrumentationScopeInfo, but I'm sure we can cook something up for that.

[tigrannajaryan]

Thanks, @jack-berg @jkwatson