Clarify logs export concurrency

[pellared]

Towards https://github.com/open-telemetry/opentelemetry-specification/issues/4134 (the same should be done for trace and metrics signal)

Inspired by https://github.com/open-telemetry/opentelemetry-specification/pull/4163

Related PR in Go SDK: https://github.com/open-telemetry/opentelemetry-go/pull/5666

Changes

• Add normative requirements for simple and batching processor.
• Change the wording in log record exporter description (we are unable to enforce how custom exporters are implemented)
• Move Each implementation MUST document the concurrency characteristics the SDK requires of the exporter. to a better place

Currently the spec says only "Export will never be called concurrently for the same exporter instance"

Remarks

For exporting to OS native tracing systems like ETW (Windows), user_events (Linux) we may provide dedicated LogRecordProcessor implementations which emit directly to them (without even implementing LogRecordExporter).

This is a change in Stable portion of specification which does not include normative language. Therefore, it may be considered as a breaking change or a as a bugfix (clarification) of the specification.

[cijothomas]

For exporting to OS native tracing systems like ETW (Windows), user_events (Linux) we may provide dedicated LogRecordProcessor implementations which emit directly to them (without even implementing LogRecordExporter).

While this is definitely feasible (and was done before too), I think its best to model them as exporters itself. Anyway, that should not block this PR, which is clarifying existing wording.

[github-actions[bot]]

This PR was marked stale due to lack of activity. It will be closed in 7 days.