Chore: Python-Spanner-Driver - Added Rows class, its methods and relevant tests...

[bhatt4982]

No description provided.

[gemini-code-assist]

Summary of Changes

Hello @bhatt4982, 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 lays the foundational groundwork for a new Python client library, spannerlib-python, designed to offer a high-performance interface to Google Cloud Spanner by leveraging the official Go client's shared library. It meticulously constructs the necessary FFI layer to bridge Python and Go, ensuring safe and efficient communication and resource management. The introduction of core abstractions like AbstractLibraryObject, Pool, Connection, and especially the Rows class, provides a structured and idiomatic Python experience for interacting with Spanner, backed by extensive testing and build automation.

Highlights

• New Python Wrapper: Introduces spannerlib-python, a high-performance Python wrapper for the Go Spanner client shared library, aiming to combine Go's performance with Python's ease of use.
• Foreign Function Interface (FFI) Layer: Establishes a robust FFI using ctypes for seamless interaction between Python and the Go shared library, including custom Message, GoString, and GoSlice types for data exchange and memory management.
• Resource Management: Implements AbstractLibraryObject as a base class for native resources, providing context manager support (with statement) and __del__ finalizers to ensure proper cleanup and prevent memory leaks.
• Core Client Classes: Adds Pool and Connection classes to manage database connections and execute various Spanner operations like SQL queries, batch DML, and mutations.
• Rows Class for Results: Introduces the Rows class to efficiently handle query results, providing methods for iterating through rows, accessing result set metadata, and retrieving update counts.
• Comprehensive Testing & Build Infrastructure: Includes a full suite of unit and system tests, along with Nox automation and a build-shared-lib.sh script, to validate the wrapper's functionality across different operating systems and against a Spanner emulator.

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[gemini-code-assist]

Code Review

This pull request introduces the core Python wrapper for the Spanner Go shared library, including the Pool, Connection, and Rows classes, along with their ctypes-based internal implementation and a comprehensive set of unit and system tests. The overall structure is well-designed, particularly the use of an abstract base class for resource management and the safety nets for handling unclosed resources. My review focuses on improving error handling consistency, clarifying documentation and log messages, and making the code more robust by avoiding silent failures and brittle exception checks. These changes will enhance the library's maintainability and developer experience.

[bhatt4982]

/gemini review

[gemini-code-assist]

Code Review

This is a comprehensive pull request that introduces a new Python wrapper for the Spanner Go library. The code is well-structured, with a clear separation of concerns between the FFI layer, public-facing objects, and utility components. The use of abstract base classes for resource management, context managers, and finalizers (__del__) to warn about unclosed resources demonstrates a strong focus on correctness and memory safety, which is crucial for a C-extension wrapper. The unit and system tests are thorough and provide good coverage. I've identified a few areas for improvement, mainly concerning a potential build script issue, consistency in error handling, and a logic bug in update_count. Overall, this is an excellent foundation for the new library.