Add specs for proxy support in exporters

[ecourreges-orange]

What are you trying to achieve?

Specs of Environment Variables needs to be added here, following added support for exporting via proxies in java and in the collector

Then PRs and implementation need to be added to the java and/or java-instrumentation and in the collector.

What did you expect to see?
Some proxy environment variables corresponding to the functionalities that were coded in February or March 2024.
So that they can be used without code in java and without digging too much.

[jack-berg]

Now that file configuration has enough pieces to build prototypes, its time to reevaluate the environment variable moratoirum, and make a choice about the future of environment variables:

Do we put a pause on future environment variables and instead only add new configurable surface area to file configuration? This incentivizes implementations of file configuration, but obviously makes things more difficult for languages which are lagging behind, and for users which aren't ready to adopt experimental features.

[austinlparker]

Question -- Is the ask here that the OTLP Exporter spec be extended to codify proxy options (potentially as SHOULD rather than MUST) and then add config support?

[ecourreges-orange]

Question -- Is the ask here that the OTLP Exporter spec be extended to codify proxy options (potentially as SHOULD rather than MUST) and then add config support?

Yes this exactly the intent of my demand. I can submit a PR for the specs if this would help (although probably not within 3 weeks because of vacations).

[krismarc]

Hey, do we have any update on this? Seems like java exporter doesn't honor -DnonProxyHosts and yet causes exporter to use proxy while it shouldn't if endpoint is whitelited. open-telemetry/opentelemetry-java-instrumentation#12240 (comment)

[trask]

@krismarc do I understand from open-telemetry/opentelemetry-java-instrumentation#12240 (comment) that issue is resolved? thanks