maintainer: add mode information in barrier logs

[hongyunyan]

What problem does this PR solve?

Issue Number: close #4427

What is changed and how it works?

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

Questions

Will it cause performance regression or break compatibility?

Do you need to update user documentation, design documentation or monitoring documentation?

Release note

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[gemini-code-assist]

Summary of Changes

Hello, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request addresses a logging deficiency in the maintainer's barrier system. Previously, barrier logs lacked replication mode information, making it difficult to differentiate between redo DDL handling and default table DDL paths. The changes introduce the replication mode into barrier event data and log outputs, providing crucial context for investigating barrier behavior and DDL execution.

Highlights

• Barrier Mode Propagation: The barrier mode is now stored on BarrierEvent objects and passed through all relevant creation paths, ensuring its availability throughout the barrier lifecycle.
• Enhanced Logging: Barrier logs in barrier.go and barrier_event.go have been updated to include the mode field, utilizing common.StringMode for clear identification of the replication mode.
• Test Updates: Barrier event tests have been adjusted to accommodate the new constructor signature for NewBlockEvent, which now accepts the barrier mode.

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Changelog

• maintainer/barrier.go
  • Added a modeField helper method to the Barrier struct for consistent logging of the barrier mode.
  • Modified HandleStatus, handleBootstrapResponse, handleEventDone, handleBlockState, getOrInsertNewEvent, checkEventFinish, and tryScheduleEvent methods to include the barrier mode in their log statements.
  • Updated calls to NewBlockEvent to pass the b.mode value.
• maintainer/barrier_event.go
  • Added a mode field to the BarrierEvent struct.
  • Modified the NewBlockEvent constructor to accept and initialize the mode field.
  • Added a modeField helper method to the BarrierEvent struct for consistent logging.
  • Updated NewBlockEvent's internal logging to include the mode.
  • Modified createRangeCheckerForTypeAll, createRangeCheckerForTypeDB, onAllDispatcherReportedBlockEvent, scheduleBlockEvent, markDispatcherEventDone, allDispatcherReported, checkBlockedDispatchers, and resend methods to include the barrier mode in their log statements.
  • Updated a log.Panic call to include the barrier mode.
• maintainer/barrier_event_test.go
  • Updated all calls to NewBlockEvent in test functions (TestScheduleEvent, TestResendAction, TestSendPassActionTypeDBIncludesWriterNode, TestUpdateSchemaID) to pass common.DefaultMode as the new mode parameter.

Activity

• No human activity has been recorded on this pull request yet.

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[coderabbitai]

📝 Walkthrough

Walkthrough

The changes add a mode parameter to the barrier event creation flow and introduce enriched logging. A new helper method logs barrier modes, the NewBlockEvent function signature is expanded to accept a mode parameter, and all call sites are updated to pass the mode. Test cases are updated accordingly with no behavioral logic modifications.

Changes

Cohort / File(s)	Summary
Barrier Mode Propagation maintainer/barrier.go, maintainer/barrier_event.go	Added modeField() helper method and updated NewBlockEvent() signature to accept an additional mode int64 parameter. Mode is now logged throughout the barrier event lifecycle (creation, range checking, dispatch, blocking, resends, scheduling) for enhanced tracing and debugging.
Test Case Updates maintainer/barrier_event_test.go	Updated all NewBlockEvent() call sites to pass common.DefaultMode as the final parameter, aligning test invocations with the updated function signature.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~12 minutes

Poem

🐰 A mode field hops through logs so bright,
The barrier tracks each event's flight,
With enriched context, debugging's delight,
New parameters bloom in test and in sight,
Our logs now sparkle with detail just right! ✨

🚥 Pre-merge checks | ✅ 1 | ❌ 2

❌ Failed checks (2 warnings)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 14.29% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.
Description check	⚠️ Warning	The PR description is mostly empty. While it includes an issue number, the critical sections 'What is changed and how it works?', test selection, and release note are completely blank.	Complete the 'What is changed and how it works?' section with a clear explanation, mark which tests were run, and provide a release note (or write 'None' if not applicable).

✅ Passed checks (1 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title 'maintainer: add mode information in barrier logs' accurately describes the main change: adding mode context to barrier event logging for better troubleshooting of redo vs. default DDL paths.

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[gemini-code-assist]

Code Review

This pull request introduces logging of the replication mode in barrier events within the maintainer. This is a valuable addition for debugging, as it helps differentiate between the redo DDL path and the default DDL path. The implementation is clean and consistent: the mode is stored in BarrierEvent and passed through all creation paths. A new modeField helper method is used to add the mode to log entries, which improves code readability and maintainability. The tests have been updated to reflect these changes. The pull request is well-executed and I have no further recommendations.

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: flowbehappy, wk989898

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Details

Needs approval from an approver in each of these files:

• OWNERS [flowbehappy,wk989898]

Approvers can indicate their approval by writing /approve in a comment
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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2026-03-11 03:21:39.317599202 +0000 UTC m=+406730.829656893: ☑️ agreed by wk989898.
• 2026-03-11 03:44:46.644148541 +0000 UTC m=+408118.156206212: ☑️ agreed by flowbehappy.

[hongyunyan]

/retest