Jack Berg

This makes sense 👍. Its somewhat related to #4389, which is about adding `TestMetricData` classes akin to `TestSpanData`. Would you be willing to contribute this?

There's a lot to review here. I think we can break this apart to separate the establishment of the key patterns from the repetition of applying that pattern to all...

I think the approach is promising. Can we see what it looks like for a small portion of the encoding, like resource? Refactoring resource to use this approach should allow...

> The programatic interface in the Java SDK is the properties supplier defined in the AutoConfigureOpenTelemetrySdkBuilder as Map> propertiesSupplier Incorrect. The programmatic interface are the builders for the specific components:...

> The properties supplier is generic enough and not dependent of any "environment variable" in order to work, if entries come from env. vars. or any other place, the map...

With that aide, let's get to the crux of what I think we ought to care about, which is how exactly file configuration should interact with the autoconfigure mechanism. I've...

> Are you aware of any java framework that starts the SDK without the Autoconfiguration? Spring, and specifically the opentelemetry [spring boot starter](https://github.com/open-telemetry/opentelemetry-java-instrumentation/tree/main/instrumentation/spring/spring-boot-autoconfigure). I don't have a list of all...

Also see this document explaining some of the original thinking behind SDK configuration design: https://github.com/open-telemetry/opentelemetry-java/blob/main/docs/sdk-configuration.md#goals-and-non-goals Note that all the emphasis is on the builders as the configuration mechanism. Note that...

> If the rich file model allows configurations that are not possible with env vars, would this mean some of the configurations could only be performed using the file? This...

> This sounds good to me in principle, but the current discussion seems to be file centric and requiring a file to work. At least in the Autoconfigure it currently...