add b3 propagator for tracing

[snowwolf007cn]

Fixes #725

Proposed Changes

• add heads-format config entry in config-tracing, default is 'w3c'
• when the backend is 'zipkin', 'b3-multi-header' and 'b3-single-header' is supported to propagate with b3 headers
• config propagator to use 'w3c' or 'b3'

Release Note

🎁 you can now config which header format(b3 multi header, b3 single header, and w3c trace-context) to be used while using Zipkin backend

Docs

[knative-prow-robot]

Welcome @snowwolf007cn! It looks like this is your first PR to knative-sandbox/eventing-kafka-broker 🎉

[knative-prow-robot]

Hi @snowwolf007cn. Thanks for your PR.

I'm waiting for a knative-sandbox member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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[pierDipi]

Awesome @snowwolf007cn !

I left some comments inline and I'd also rename everywhere headsFormat to headersFormat for better clarity.

[pierDipi]

@snowwolf007cn there is a problem with the CLA, please take a look: https://github.com/knative-sandbox/eventing-kafka-broker/pull/1546/checks?check_run_id=4331388121

[snowwolf007cn]

@snowwolf007cn there is a problem with the CLA, please take a look: https://github.com/knative-sandbox/eventing-kafka-broker/pull/1546/checks?check_run_id=4331388121

I think you've rescanned.

[pierDipi]

/ok-to-test

Some more renaming.

[codecov]

Codecov Report

Merging #1546 (c736ef7) into main (1ae3943) will decrease coverage by 0.00%.
The diff coverage is 80.64%.

@@             Coverage Diff              @@
##               main    #1546      +/-   ##
============================================
- Coverage     75.33%   75.33%   -0.01%     
- Complexity      588      593       +5     
============================================
  Files           107      107              
  Lines          4128     4152      +24     
  Branches        165      170       +5     
============================================
+ Hits           3110     3128      +18     
- Misses          762      765       +3     
- Partials        256      259       +3     

Flag	Coverage Δ
java-unittests	82.01% <80.64%> (-0.09%)	⬇️

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

Impacted Files	Coverage Δ
...nting/kafka/broker/core/tracing/TracingConfig.java	73.72% <80.64%> (+0.32%)	⬆️

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[pierDipi]

@snowwolf007cn the failure wants you to regenerate the file with third-party licenses by running this command:

./mvnw -Dlicense.outputDirectory=. license:aggregate-add-third-party

[pierDipi]

inside the data-plane directory.

[snowwolf007cn]

/retest

[pierDipi]

/lgtm
/approve

Thank you!

[knative-prow-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: pierDipi, snowwolf007cn

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• OWNERS [pierDipi]

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[pierDipi]

/kind enhancement

[hassanbenhzaine]

Hello everyone, could someone please show me how to replace knative propagator to use B3 instead if W3C by default