fix(mcp): prefer ADC project for billing checks

[VishnuVardhanBR]

Description

• prefer MCP project resolution from GOOGLE_APPLICATION_CREDENTIALS (project_id / quota_project_id) over local default project context
• make MCP billing checks resilient so unauthorized billing API checks no longer fail startup/listing flows
• add regression tests for credential-project precedence and billing-failure fallback
• add changelog entry for [MCP] Startup billing check uses default project and fails init when credentials target another project #9983

Testing

• npx mocha src/mcp/index.spec.ts
• npm run test:compile

Fixes #9983

[gemini-code-assist]

Summary of Changes

Hello, 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 enhances the Firebase MCP server's project identification and billing check mechanisms. It introduces a preference for project IDs specified via GOOGLE_APPLICATION_CREDENTIALS, ensuring that the correct project context is used, especially in environments where service accounts are prevalent. Furthermore, it improves the resilience of billing status checks by preventing unauthorized API access errors from disrupting core server functionalities, thereby making the system more robust.

Highlights

• Project ID Resolution: The system now prioritizes project IDs found in GOOGLE_APPLICATION_CREDENTIALS (specifically project_id or quota_project_id) over locally configured default project contexts.
• Resilient Billing Checks: Billing API checks are now more robust; if an unauthorized billing API check occurs, it will no longer cause startup or listing flows to fail, instead gracefully returning false.
• Regression Tests Added: New tests have been introduced to verify the precedence of credential-based project IDs and the fallback mechanism for billing check failures.
• Changelog Updated: A changelog entry has been added to document these changes.

🧠 New Feature in Public Preview: You can now enable Memory to help Gemini Code Assist learn from your team's feedback. This makes future code reviews more consistent and personalized to your project's style. Click here to enable Memory in your admin console.

Changelog

• CHANGELOG.md
  • MCP now prefers the project from Application Default Credentials and no longer fails startup when billing checks are unauthorized ([MCP] Startup billing check uses default project and fails init when credentials target another project #9983)

Activity

• The author, VishnuVardhanBR, created this pull request to address issue [MCP] Startup billing check uses default project and fails init when credentials target another project #9983.
• The pull request includes new features, refactoring, and regression tests.
• No specific reviewer comments or approvals are provided in the context.

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 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. If you're interested in giving your feedback about your experience with Gemini Code Assist for Github and other Google products, sign up here.

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 improves project resolution by prioritizing Application Default Credentials and makes billing checks more resilient to permission errors, preventing startup failures. The changes are well-tested. I have a suggestion to improve the implementation by using asynchronous file I/O to prevent blocking the event loop, which is a best practice for server-side code.