Fall back to otel env vars for tracing endpoint, headers, and resource attributes, in a similar way as micrometer does for metrics.
This gives users the option to use the same settings for tracing and metrics - and even the same as in other languages.
Why no spring properties? - to make it more similar to metrics - resource attributes and headers need to be parsed from a string - this approach doesn't require a converter.
Note: tests will be added later - need a hint how to test env vars.
Comment From: zeitlinger
I'm wondering if this logic should actually be in micrometer tracing, since it only depends on env vars.
Comment From: wilkinsona
We discussed this today and our feeling is that if this logic belongs anywhere, it should go in Micrometer as it doesn't appear to be Spring Boot-specific. That said, if we wanted to use Spring's Environment rather than working directly with System.getEnv(), it could not be done in Micrometer. We'll discuss further soon, hopefully next week.
Comment From: zeitlinger
We discussed this today and our feeling is that if this logic belongs anywhere, it should go in Micrometer as it doesn't appear to be Spring Boot-specific.
I think this would be a good idea.
Comment From: wilkinsona
We discussed this again today and concluded that this does belong in Micrometer tracing as a companion to the existing, similar logic for metrics. Thanks anyway for the proposal.