fix: handle shutdown in logs exporter

[stefanobaghino]

Fixes #2777

Changes

This follows the approach suggested here by @scottgerring:

The issue is in TonicLogsClient which uses tokio::sync::Mutex (async) but the LogExporter::shutdown_with_timeout() trait method is synchronous. This prevents calling .lock().await, so the current implementation has a TODO and just returns Ok() without actually shutting down the gRPC client.

Comparing shutdown on TonicMetricsClient , and in particular the type of the mutex used for the inner client and locked in the shutdown, seems to show a workable pattern.

Merge requirement checklist

• CONTRIBUTING guidelines followed
• Unit tests added/updated (if applicable)
• Appropriate CHANGELOG.md files updated for non-trivial, user-facing changes
• Changes in public API reviewed (if applicable)

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: cijothomas / name: Cijo Thomas (a92adb7)

[codecov]

Codecov Report

❌ Patch coverage is 0% with 23 lines in your changes missing coverage. Please review.
✅ Project coverage is 80.7%. Comparing base (53c9f47) to head (a92adb7).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
opentelemetry-otlp/src/exporter/tonic/logs.rs	0.0%	22 Missing ⚠️
opentelemetry-otlp/src/exporter/tonic/metrics.rs	0.0%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##            main   #3255     +/-   ##
=======================================
- Coverage   80.8%   80.7%   -0.1%     
=======================================
  Files        129     129             
  Lines      23203   23212      +9     
=======================================
  Hits       18750   18750             
- Misses      4453    4462      +9     

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[scottgerring]

Thanks! LGTM

[scottgerring]

I think this is helpful; I don't think the user would necessarily see which failed otherwise

[scottgerring]

@stefanobaghino that was a quick turnaround :D

[stefanobaghino]

I'd be happy to take any additional feedback on this. If this is not a satisfactory approach, I also have nothing against closing this. Please let me know how to progress. Thanks.

[scottgerring]

I'd be happy to take any additional feedback on this. If this is not a satisfactory approach, I also have nothing against closing this. Please let me know how to progress. Thanks.

Hey @stefanobaghino should be fine; let's just wait on @cijothomas 's feedback! He ultimately holds the merge approval.

[cijothomas]

LGTM. Thank you!