dataconnect(test): ConnectRPCIntegrationTest.kt: add more tests

[dconeybe]

This PR significantly expands the integration tests for the Data Connect Connect RPC service and introduces several utility methods for proto manipulation and debugging.

Highlights

• Expanded Integration Tests: Added a wide range of new test cases to ConnectRPCIntegrationTest.kt, covering successful operations, error conditions (e.g., non-existent operations, missing init), and various coroutine/channel lifecycle scenarios (cancellation, closure, etc.).
• Property-Based Testing: Introduced Kotest property-based testing for StreamRequest using a new validStreamRequestArb generator.
• Proto Utilities: Added several helper methods to ProtoUtil.kt for converting StreamRequest and StreamResponse objects to compact strings and Struct protos, facilitating better logging and testing.
• Structured Header Support: Implemented putHeaders in DataConnectGrpcMetadata and StructProtoBuilder to allow for consistent, structured representation of gRPC metadata.
• Enhanced Test Output: Expanded KotestPrinters.kt to include custom printers for various Data Connect proto types, improving the readability of test failure messages.

Changelog

5 files changed

• ConnectRPCIntegrationTest.kt: Significantly expanded with new test cases for queries, mutations, error handling, and channel lifecycle management. Added property-based testing support.
• DataConnectGrpcClient.kt: Minor import and visibility adjustments.
• DataConnectGrpcMetadata.kt: Added putHeaders utility for structured metadata representation.
• ProtoUtil.kt: Implemented compact string and Struct proto conversion helpers for StreamRequest and StreamResponse.
• KotestPrinters.kt: Added custom printers for GraphqlError, StreamRequest, StreamResponse, and SourceLocation protos.

[github-actions]

📝 PRs merging into main branch

Our main branch should always be in a releasable state. If you are working on a larger change, or if you don't want this change to see the light of the day just yet, consider using a feature branch first, and only merge into the main branch when the code complete and ready to be released.

[dconeybe]

/gemini review

[gemini-code-assist]

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 by creating a comment using either /gemini <command> or @gemini-code-assist <command>. Below is a summary of the supported commands on the current page.

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 pull request comments and review comments.
Help	/gemini help	Displays a list of available commands.

Customization

To customize the 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 counterproductive. You can react with 👍 and 👎 on @gemini-code-assist comments. If you're interested in giving your feedback about your experience with Gemini Code Assist for GitHub and other Google products, sign up here.

[gemini-code-assist]

Code Review

This pull request significantly expands the integration testing suite for Data Connect RPC, adding coverage for various success and failure scenarios, including stream cancellation and lifecycle management. It also introduces utility methods and Kotest printers to facilitate the conversion of gRPC stream messages to human-readable formats for debugging. Feedback includes addressing a potential compilation error in ProtoUtil.kt regarding subscribe request handling, simplifying the conversion logic for StreamResponse data, and improving the robustness of test helper methods to prevent potential hangs.