End-to-end minimalistic ppl

[wu-hui]

An end-to-end ppl prototype

[gemini-code-assist]

Hello @wu-hui, 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!

Summary of Changes

This pull request introduces a new Pipeline feature to the Firestore iOS SDK, enabling the execution of complex queries through a series of stages. The changes include modifications to the Firestore example project to incorporate the new Pipeline functionality, along with updates to protobuf definitions and build configurations to support the feature.

Highlights

• Pipeline Feature: Adds Pipeline support to the Firestore iOS SDK, allowing for more complex data retrieval operations.
• Project Configuration: Updates the Firestore example project's build configuration to include new source files and dependencies required for the Pipeline feature.
• Protobuf Definitions: Includes new protobuf definitions for explain_stats and pipeline to support the Pipeline feature.

Changelog

Click here to see the changelog

• Firestore/CHANGELOG.md
  • Adds a changelog entry indicating the addition of Pipeline support.
• Firestore/Example/Firestore.xcodeproj/project.pbxproj
  • Modifies the project file to include new source files related to explain_stats, field_behavior, and pipeline.
  • Adds PipelineTests.swift to the project's sources.
  • Updates the project's build settings and file references to accommodate the new feature.
• Firestore/Protos/CMakeLists.txt
  • Updates the CMakeLists.txt file to include new protobuf definitions for explain_stats, field_behavior, and pipeline.
• Firestore/Protos/cpp/firestore/*
  • Updates copyright headers to 2025.
  • Adds new protobuf definitions for explain_stats, field_behavior, and pipeline.
• Firestore/Protos/nanopb/firestore/*
  • Adds new nanopb definitions for explain_stats, field_behavior, and pipeline.
• Firestore/Swift/Source/SwiftAPI/*
  • Adds new Swift files to implement the Pipeline feature
• Firestore/Swift/Tests/Integration/PipelineTests.swift
  • Adds new Swift tests for the Pipeline feature

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The .proto file extension is used for Protocol Buffer definition files. These files define the structure of the data you want to serialize.

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[gemini-code-assist]

Code Review

This pull request introduces the Pipeline feature to Firestore, enabling the execution of a series of operations in a structured manner. The changes span across multiple files, including updates to the iOS example project, protobuf definitions, nanopb configurations, and core C++ and Swift implementations. Overall, the feature seems well-structured, but there are several areas that need closer inspection and potential adjustments.

Summary of Findings

• Copyright Year: The copyright year in several files is updated to 2025. Ensure this is the correct and intended year.
• Missing Tests: The pull request introduces a significant new feature (Pipeline), but there's a lack of comprehensive tests, particularly in the core C++ implementation. While a Swift integration test is added, core logic requires more robust testing.
• Incomplete Error Handling: The RunPipeline methods in FirestoreClient and RemoteStore do not handle errors when creating the request or processing the response. This could lead to unhandled exceptions or incorrect states.
• Inconsistent Naming: The naming of certain variables and methods (e.g., internal_value in PipelineResult) could be more descriptive and consistent with existing conventions.

Merge Readiness

The pull request introduces a significant new feature, but it's not yet ready for merging. The copyright year, missing tests, and incomplete error handling need to be addressed before merging. I am unable to approve this pull request, and recommend that it not be merged until the above issues are addressed (at a minimum).

[google-oss-bot]

	1 Warning
⚠️	Did you forget to add a changelog entry? (Add #no-changelog to the PR description to silence this warning.)

Generated by 🚫 Danger

[cherylEnkidu]

I took a high level review of the overall structure. The obj-c layer looks really nice!