Improve logging in Consensus Commit

[brfrn169]

Description

This PR improves logging in Consensus Commit to improve observability and debugging.

Related issues and/or PRs

N/A

Changes made

• Improved logging in Consensus Commit.

Checklist

The following is a best-effort checklist. If any items in this checklist are not applicable to this PR or are dependent on other, unmerged PRs, please still mark the checkboxes after you have read and understood each item.

• I have commented my code, particularly in hard-to-understand areas.
• I have updated the documentation to reflect the changes.
• I have considered whether similar issues could occur in other products, components, or modules if this PR is for bug fixes.
• Any remaining open issues linked to this PR are documented and up-to-date (Jira, GitHub, etc.).
• Tests (unit, integration, etc.) have been added for the changes.
• My changes generate no new warnings.
• Any dependent changes in other PRs have been merged and published.

Additional notes (optional)

N/A

Release notes

N/A

[Copilot]

Pull Request Overview

This PR improves observability and debugging capabilities in the Consensus Commit module by enhancing logging throughout the codebase. The changes add detailed transaction context to error and warning messages, providing better debugging information when issues occur.

Key changes:

• Enhanced error messages to include specific transaction details like Transaction IDs, table names, and partition/clustering keys
• Improved exception handling with more detailed error messages and better context propagation
• Refactored NoMutationException to include mutation details for better error reporting

Reviewed Changes

Copilot reviewed 25 out of 26 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
RecoveryHandlerTest.java	Updated test setup to mock additional transaction metadata components
RecoveryExecutorTest.java	Fixed test to use proper transaction ID in coordinator state mocking
TwoPhaseConsensusCommitManager.java	Added transaction ID to rollback failure warning logs
TwoPhaseConsensusCommit.java	Enhanced error messages with exception details and replaced snapshot ID calls with direct getId()
Snapshot.java	Added transaction ID to scanner closure warning logs
RecoveryHandler.java	Extensively improved logging with detailed table, key, and transaction information
RecoveryExecutor.java	Enhanced error messages and added detailed uncommitted record exception context
ParallelExecutor.java	Improved task naming and added exception details to parallel execution logs
CrudHandler.java	Enhanced error handling and scanner closure logging with transaction context
Coordinator.java	Improved retry logic with better exception handling and detailed logging
ConsensusCommitMutationOperationChecker.java	Refactored to use utility method for table metadata retrieval
ConsensusCommitManager.java	Added transaction ID to rollback failure warning logs
ConsensusCommit.java	Enhanced error messages and replaced snapshot ID calls with direct getId()
CommitMutationComposer.java	Added assertion to validate transaction state
CommitHandler.java	Comprehensive error message improvements with exception details
JdbcDatabase.java	Updated NoMutationException constructor calls to include mutation details
Storage handlers	Updated NoMutationException usage across DynamoDB, Cosmos, and Cassandra handlers
NoMutationException.java	Major refactor to include mutation details and enhanced error messaging
CoreError.java	Updated error message templates to include placeholders for detailed information

Comments suppressed due to low confidence (2)

core/src/main/java/com/scalar/db/transaction/consensuscommit/Coordinator.java:326

• Missing closing brace for the while loop. The code structure shows an incomplete while loop that needs proper closure.

  }

core/src/main/java/com/scalar/db/transaction/consensuscommit/Coordinator.java:372

• Missing closing brace for the while loop. The code structure shows an incomplete while loop that needs proper closure.

  }

[gemini-code-assist]

Summary of Changes

Hello @brfrn169, 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 significantly enhances the logging and error reporting capabilities within the Consensus Commit transaction framework. The primary goal is to improve observability and debugging by providing more detailed and contextual information in error messages and log outputs. This includes enriching exception details, adding transaction-specific identifiers to logs, and refining the handling of internal exceptions to offer clearer insights into transaction states and failures.

Highlights

• Enhanced Error Messages: Many CoreError messages related to Consensus Commit have been updated to include %s placeholders, allowing for dynamic insertion of specific details. Notably, the CONSENSUS_COMMIT_READ_UNCOMMITTED_RECORD error now provides comprehensive information including the table, partition key, clustering key, and the transaction ID that wrote the record, significantly aiding debugging.
• Improved NoMutationException Details: The NoMutationException class has been refactored to accept and store the list of Mutation objects that failed to apply. This enhancement allows the exception message to include detailed information about the specific mutations (type, table, and keys), making it much easier to diagnose issues when conditional mutations do not satisfy their conditions.
• Detailed Logging Across Components: Log messages throughout various Consensus Commit components, including CommitHandler, ConsensusCommit, CrudHandler, Coordinator, ParallelExecutor, and RecoveryHandler, have been enriched. They now consistently include transaction IDs and more specific error details, greatly improving the observability and traceability of transaction flows.
• Refined Exception Handling and Retries: Exception handling in the Coordinator and CrudHandler has been improved to aggregate suppressed exceptions, providing a more complete picture of the error chain during retries or recovery processes. This helps in understanding the root cause of transient failures.
• Adjusted Logging Levels for Expected Flows: Some logger.warn calls that previously indicated expected or non-critical scenarios (such as certain lazy recovery operations) have been changed to logger.info. This adjustment reduces noise in the logs, allowing developers to focus on genuinely problematic warnings while still retaining visibility into normal operational flows.

Using Gemini Code Assist

The full guide for Gemini Code Assist can be found on our documentation page, here are some quick tips.

Invoking Gemini

You can request assistance from Gemini at any point in your pull request via creating an issue comment (i.e. comment on the pull request page) using either /gemini <command> or @gemini-code-assist <command>. Below is a summary of the supported commands.

Feature	Command	Description
Code Review	/gemini review	Performs a code review for the current pull request in its current state.
Pull Request Summary	/gemini summary	Provides a summary of the current pull request in its current state.
Comment	@gemini-code-assist	Responds in comments when explicitly tagged, both in issue comments and review comments.
Help	/gemini help	Displays a list of available commands.

Customization

To customize Gemini Code Assist for GitHub experience, repository maintainers can create a configuration file and/or provide a custom code review style guide (such as PEP-8 for Python) by creating and adding files to a .gemini/ folder in the base of the repository. Detailed instructions can be found here.

Limitations & Feedback

Gemini Code Assist may make mistakes. Please leave feedback on any instances where its feedback is incorrect or counter productive. You can react with 👍 and 👎 on @gemini-code-assist comments or fill out our survey to provide feedback.

You can also get AI-powered code generation, chat, as well as code reviews directly in the IDE at no cost with the Gemini Code Assist IDE Extension.

Footnotes

1. Review the Privacy Notices, Generative AI Prohibited Use Policy, Terms of Service, and learn how to configure Gemini Code Assist in GitHub here. Gemini can make mistakes, so double check it and use code with caution. ↩

[gemini-code-assist]

Code Review

This pull request significantly improves logging and observability within the Consensus Commit protocol. Key changes include:

• Enhancing error messages in CoreError to include detailed, context-specific information.
• Refactoring NoMutationException to include a list of mutations that failed, providing crucial debugging information.
• Improving retry logic in the Coordinator with better exception handling and more informative logging.
• Adding transaction IDs to numerous log messages for easier tracing.
• Refactoring code for better organization, such as moving utility methods to ConsensusCommitUtils.

The changes are well-implemented and will be very beneficial for debugging and monitoring. I have a couple of minor suggestions for improving code style and consistency.

[komamitsu]

LGTM, thank you!

[feeblefakie]

LGTM! Thank you!

[Torch3333]

LGTM, thank you!