Support batch operation in Transaction API

[brfrn169]

Description

This PR adds support for batch operations that perform multiple operations in the Transaction API.

Related issues and/or PRs

N/A

Changes made

• Introduced a new batch() method in the CrudOperable interface that accepts a list of operations and returns batch results
• Implemented batch operation support across all transaction types (distributed, two-phase commit, JDBC, and single CRUD)
• Added BatchResult interface and BatchResultImpl class to encapsulate operation results
• Removed unnecessary consistency settings from test utility methods

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

Added support for batch operations that perform multiple operations in the Transaction API.

[Copilot]

Pull Request Overview

This PR adds support for batch operations in the Transaction API, enabling multiple operations to be executed together in a single batch call. The implementation includes support for both read operations (Get, Scan) and mutation operations (Put, Insert, Upsert, Update, Delete) across various transaction implementations.

Key Changes:

• Introduced a new batch() method in the CrudOperable interface that accepts a list of operations and returns batch results
• Implemented batch operation support across all transaction types (distributed, two-phase commit, JDBC, and single CRUD)
• Added BatchResult interface and BatchResultImpl class to encapsulate operation results
• Removed unnecessary consistency settings from test utility methods

Reviewed Changes

Copilot reviewed 42 out of 42 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
core/src/main/java/com/scalar/db/api/CrudOperable.java	Added batch() method signature and BatchResult interface to the core API
core/src/main/java/com/scalar/db/common/BatchResultImpl.java	New implementation class for batch operation results
core/src/main/java/com/scalar/db/common/AbstractDistributedTransaction.java	Implemented batch() and mutate() methods with operation dispatching logic
core/src/main/java/com/scalar/db/common/AbstractTwoPhaseCommitTransaction.java	Implemented batch() and mutate() methods for two-phase commit transactions
core/src/main/java/com/scalar/db/common/ReadOnlyDistributedTransaction.java	Added validation to prevent mutations in read-only batch operations
core/src/main/java/com/scalar/db/util/ScalarDbUtils.java	Updated utility to handle Operation type instead of just Mutation
core/src/main/java/com/scalar/db/transaction/singlecrudoperation/SingleCrudOperationTransactionManager.java	Implemented batch() with single operation restriction
integration-test/src/main/java/com/scalar/db/api/TwoPhaseCommitTransactionIntegrationTestBase.java	Added comprehensive integration tests for batch operations and removed unnecessary consistency settings
integration-test/src/main/java/com/scalar/db/api/DistributedTransactionIntegrationTestBase.java	Added integration tests for batch operations in distributed transactions
core/src/test/java/com/scalar/db/transaction/consensuscommit/TwoPhaseConsensusCommitTest.java	Added unit tests for batch operations

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[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 Transaction API by introducing a batch operation, enabling users to execute multiple CRUD operations efficiently within a single transaction. This new functionality streamlines interactions with the database, potentially reducing network overhead and simplifying application logic. The changes involve extending core interfaces, providing concrete implementations, and updating utility classes and error handling to support this new batch capability, ensuring robust and consistent behavior across different transaction types.

Highlights

• New Batch Operation API: Introduced a new batch method in the CrudOperable interface, allowing multiple Operation commands (Get, Scan, Put, Insert, Upsert, Update, Delete) to be executed as a single unit within a transaction. This method returns a list of BatchResult objects, corresponding to the results of each operation.
• BatchResult Interface and Implementation: Added a new BatchResult interface and its implementation BatchResultImpl to encapsulate the outcome of individual operations within a batch. It provides methods to retrieve the operation type and specific results for GET and SCAN operations.
• Consolidated Mutation Handling: Refactored the mutate method implementation into AbstractDistributedTransaction and AbstractTwoPhaseCommitTransaction, centralizing the logic for handling lists of mutations. This reduces code duplication across various transaction implementations.
• Updated ScalarDbUtils: Modified ScalarDbUtils to support copying and setting target information for a list of generic Operation objects, ensuring consistency across different operation types.
• Error Handling and Single CRUD Transaction Support: Introduced new error codes for empty operation lists and unsupported multiple operations in single CRUD operation transactions. The SingleCrudOperationTransactionManager now explicitly restricts mutate and batch methods to a single operation.
• Thread Safety for Scanners: Synchronized the getScanner methods within ActiveTransactionManagedDistributedTransactionManager and ActiveTransactionManagedTwoPhaseCommitTransactionManager to ensure thread safety when accessing scanners.
• Integration Tests: Added comprehensive integration tests for the new batch functionality across various transaction managers, including scenarios with default namespaces and mixed operation types, and updated existing tests to reflect the new API.

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[gemini-code-assist]

Code Review

This PR adds support for batch operations in the Transaction API. The changes are extensive, touching many interfaces and their implementations to add the batch method. The core logic is centralized in abstract classes like AbstractDistributedTransaction, which is a good design choice. The integration tests are also updated to cover the new functionality. My review includes a few suggestions to improve the Javadoc clarity and the immutability of the new BatchResultImpl class.

[komamitsu]

LGTM! 👍

[feeblefakie]

LGTM! Thank you!
Left one question for clarification. PTAL!

[Torch3333]

LGTM, thank you!

[feeblefakie]

LGTM! Thank you!