Deprecate JaegerPropagator in OpenTelemetry.Extensions.Propagators

[neeraj542]

Description

This PR deprecates the JaegerPropagator class and all its public members in the OpenTelemetry.Extensions.Propagators package, following the OpenTelemetry specification change (opentelemetry-specification#4827) and Jaeger's migration guide.

Changes

• Added [Obsolete] attributes to JaegerPropagator class
• Added [Obsolete] attributes to all public members (Fields, Extract, Inject)
• Updated README.md with deprecation notice and migration guidance
• Added #pragma warning disable CS0809 to handle obsolete member overrides

Related Issues

Fixes #6814

Migration Path

Users should migrate to TraceContextPropagator from the OpenTelemetry package instead. See:

• Jaeger's migration guide
• OpenTelemetry specification issue #4827

Testing

• ✅ Build succeeds for all target frameworks
• ✅ All tests pass (54/54 on net10.0)
• ✅ Obsolete warnings appear correctly when using JaegerPropagator
• ✅ Markdown linting passes
• ✅ No PublicAPI file changes needed (only adding attributes, not changing signatures)

Screenshot:

[neeraj542]

Hi @Kielek,

I've implemented the deprecation of JaegerPropagator per #6814. The changes include:

• Added [Obsolete] attributes to the class and all public members
• Updated README.md with deprecation notice
• Fixed formatting (formatter also added [Obsolete] to test methods)

I have a few questions:

1. Is adding [Obsolete] to test methods the right approach, or should we suppress warnings differently?
2. Are the deprecation messages appropriate?
3. Should I wait for all CI checks to complete, or address specific issues now?

This is my first contribution here, so I'd appreciate any feedback or guidance. Happy to make adjustments as needed!

Thanks!

[neeraj542]

I've done this [!NOTE] syntax change. Thanks, @martincostello!

[neeraj542]

the PR is now updated and ready for your review. Please let me know if there's anything else that needs to be adjusted.

[martincostello]

There's a bunch of compiler errors that need addressing.

[neeraj542]

@martincostello I've fixed the compiler errors. CI completed but shows 35 failing checks. I'm reviewing the error messages to see if they're related to my changes or infrastructure issues.

Could you help clarify which failures (if any) are related to the deprecation changes? I want to make sure I address the right issues. Thanks!

[martincostello]

They're all related to the changes you've made.

[neeraj542]

They're all related to the changes you've made.

I'm reviewing the error logs now. I'll fix all issues related to my changes. Should I focus on any particular checks first (markdown linting, sanity check, build errors, etc.)?

[martincostello]

The order doesn't really matter. They'd all have to be resolved for merge.

[neeraj542]

I'm having trouble seeing the specific error messages from the failing CI checks. The build is clean locally (0 warnings/errors in Release, all 54 tests pass on net10.0), but CI shows 35 failing checks.

Could you help me understand:

1. What are the specific error messages I should be looking at?
2. Are there particular failing checks I should focus on first?
3. Is there a way to see the detailed test failure output in CI?

I want to fix all the issues but need to see the actual errors to address them. Thanks for your help! @martincostello

[martincostello]

All the logs are here: https://github.com/open-telemetry/opentelemetry-dotnet/actions/runs/21004722193

[martincostello]

Also note that in CI all warnings as treated as errors, so if you have any warnings in your build locally, those also need to be fixed.

[Kielek]

Also note that in CI all warnings as treated as errors, so if you have any warnings in your build locally, those also need to be fixed.

The bare minimum local check is to execute solution build in the Release mode. If it fails locally, it will fail also in the CI.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 86.99%. Comparing base (518fcf1) to head (059c893).
⚠️ Report is 13 commits behind head on main.
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6819      +/-   ##
==========================================
+ Coverage   86.91%   86.99%   +0.08%     
==========================================
  Files         262      263       +1     
  Lines       12355    12490     +135     
==========================================
+ Hits        10738    10866     +128     
- Misses       1617     1624       +7     

Flag	Coverage Δ
unittests-Project-Experimental	86.54% <ø> (-0.25%)	⬇️
unittests-Project-Stable	86.56% <ø> (-0.29%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
...lemetry.Extensions.Propagators/JaegerPropagator.cs	94.02% <ø> (ø)

... and 6 files with indirect coverage changes

[neeraj542]

All CI checks have passed now..

Fixed the CS0809 error by adding pragma warnings around the Fields property, and removed the trailing space in README.md. All 46 checks are now passing, including build tests, package validation, and AOT compatibility tests.

The PR is ready for review. Thanks!

cc: @martincostello @Kielek

[Kielek]

LGTM. Thanks.

Note for myseld/other approvers: Jaeger propagator was never part of OpenTelemetry.Context.Propagation namespace. It was implemented only in this package.

[neeraj542]

Thanks for the review and approval.. If everything looks good here, could you please merge this PR?

cc: @martincostello , @Kielek

[rajkumar-rangaraj]

@Kielek Merging is blocked due to validation failure. Have you seen this earlier?

[rajkumar-rangaraj]

@Kielek Merging is blocked due to validation failure. Have you seen this earlier?

Nevermind, it took few minutes to show merge button.

[neeraj542]

Thanks for the review and merge! Appreciate it 🙌