Gerrit Review MCP Server

Gerrit Review MCP Server

This MCP server provides integration with Gerrit code review system, allowing AI assistants to review code changes and their details through a simple interface.

Features

The server provides a streamlined toolset for code review:

Fetch Change Details

fetch_gerrit_change(change_id: str, patchset_number: Optional[str] = None)

• Fetches complete change information including files and patch sets
• Shows detailed diff information for each modified file
• Displays file changes, insertions, and deletions
• Supports reviewing specific patch sets
• Returns comprehensive change details including:
  • Project and branch information
  • Author and reviewer details
  • Comments and review history
  • File modifications with diff content
  • Current patch set information

Compare Patchset Differences

fetch_patchset_diff(change_id: str, base_patchset: str, target_patchset: str, file_path: Optional[str] = None)

• Compare differences between two patchsets of a change
• View specific file differences or all changed files
• Analyze code modifications across patchset versions
• Track evolution of changes through review iterations

Submit Review Feedback

submit_gerrit_review(
    change_id: str,
    message: Optional[str] = None,
    patchset_number: Optional[str] = None,
    labels: Optional[Dict[str, int]] = None,
    comments: Optional[List[Dict[str, Any]]] = None,
    notify: str = "OWNER",
)

• Post summary feedback, vote labels (e.g., {"Code-Review": 1}), and inline/file-level comments
• Target a specific patchset or default to the latest revision
• Control Gerrit's notification behaviour (notify: NONE, OWNER, OWNER_REVIEWERS, ALL)
• Comment payloads accept dictionaries with path, message, and optional Gerrit comment fields (line, side, range, ...)

Example Usage

Review a complete change:

# Fetch latest patchset of change 23824
change = fetch_gerrit_change("23824")

Submit review feedback with a vote and inline comment:

submit_gerrit_review(
    change_id="23824",
    message="Looks good overall",
    labels={"Code-Review": 1},
    comments=[{"path": "src/app.py", "line": 42, "message": "Nice refactor."}],
    patchset_number="2",           # optional: target a specific patchset
    notify="OWNER_REVIEWERS",      # optional: adjust notification scope
)

Compare specific patchsets:

# Compare differences between patchsets 1 and 2 for change 23824
diff = fetch_patchset_diff("23824", "1", "2")

View specific file changes:

# Get diff for a specific file between patchsets
file_diff = fetch_patchset_diff("23824", "1", "2", "path/to/file.swift")

Prerequisites

• Python 3.10 or higher (Python 3.11 recommended)
• Gerrit HTTP access credentials
• HTTP password generated from Gerrit settings
• Access to the mcp[cli] package repository (private package)

Installation

Installing via Smithery

To install gerrit-code-review-mcp for Claude Desktop automatically via Smithery:

npx -y @smithery/cli install @cayirtepeomer/gerrit-code-review-mcp --client claude

Manual Installation

1. Clone this repository:

git clone <repository-url>
cd gerrit-review-mcp

2. Create and activate a virtual environment:

# For macOS/Linux:
python -m venv .venv
source .venv/bin/activate

# For Windows:
python -m venv .venv
.venv\Scripts\activate

3. Install this package in editable mode with its dependencies:

pip install -e .

Configuration

1. Set up environment variables:

export GERRIT_HOST="gerrit.example.com"  # Your Gerrit server hostname (without https://)
export GERRIT_USER="your-username"       # Your Gerrit account username
export GERRIT_HTTP_PASSWORD="your-http-password"  # Generated HTTP password from Gerrit Settings > HTTP Credentials
export GERRIT_EXCLUDED_PATTERNS="\.pbxproj$,\.xcworkspace$,node_modules/"  # Optional: regex patterns for files to exclude from reviews
# Optional TLS configuration for custom or self-signed certificates
export GERRIT_SSL_VERIFY="true"              # Set to 'false' to skip TLS verification in constrained environments
export GERRIT_CA_BUNDLE="/path/to/ca.pem"    # Optional custom CA bundle path used when verification stays enabled
# Note: If both are set, GERRIT_CA_BUNDLE takes precedence and verification stays enabled using that bundle.

Or create a .env file:

GERRIT_HOST=gerrit.example.com
GERRIT_USER=your-username
GERRIT_HTTP_PASSWORD=your-http-password
GERRIT_EXCLUDED_PATTERNS=\.pbxproj$,\.xcworkspace$,node_modules/
GERRIT_SSL_VERIFY=true
GERRIT_CA_BUNDLE=/path/to/ca.pem
# If both are set, the CA bundle wins.

2. Generate HTTP password:

• Log into your Gerrit web interface
• Go to Settings > HTTP Credentials
• Generate new password
• Copy the password to your environment or .env file

3. Configure file exclusions (optional):

• Set GERRIT_EXCLUDED_PATTERNS to exclude specific file types from change reviews
• Use comma-separated regex patterns (e.g., \.pbxproj$,\.xcworkspace$,node_modules/)
• Leave empty or unset to use default exclusions
• This helps prevent infinite loops with large files

MCP Configuration

To use this MCP server with Cursor or RooCode, you need to add its configuration to your ~/.cursor/mcp.json or .roo/mcp.json file. Here's the required configuration:

{
  "mcpServers": {
    "gerrit-review-mcp": {
      "command": "/path/to/your/workspace/gerrit-code-review-mcp/.venv/bin/python",
      "args": [
        "/path/to/your/workspace/gerrit-code-review-mcp/server.py",
        "--transport",
        "stdio"
      ],
      "cwd": "/path/to/your/workspace/gerrit-code-review-mcp",
      "env": {
        "PYTHONPATH": "/path/to/your/workspace/gerrit-code-review-mcp",
        "VIRTUAL_ENV": "/path/to/your/workspace/gerrit-code-review-mcp/.venv",
        "PATH": "/path/to/your/workspace/gerrit-code-review-mcp/.venv/bin:/usr/local/bin:/usr/bin:/bin"
      },
      "stdio": true
    }
  }
}

Replace /path/to/your/workspace with your actual workspace path. For example, if your project is in /Users/username/projects/gerrit-code-review-mcp, use that path instead.

Make sure all paths in the configuration point to:

• Your virtual environment's Python interpreter
• The project's server.py file
• The correct working directory
• The virtual environment's bin directory in the PATH

Implementation Details

The server uses Gerrit REST API to interact with Gerrit, providing:

• Fast and reliable change information retrieval
• Secure authentication using HTTP digest auth
• Support for various Gerrit REST endpoints
• Clean and maintainable codebase
• HTTPS encryption for secure communication

Troubleshooting

If you encounter connection issues:

1. Verify your HTTP password is correctly set in GERRIT_HTTP_PASSWORD
2. Check GERRIT_HOST setting (hostname only, without https://)
3. Ensure HTTPS access is enabled on Gerrit server
4. Test connection using curl with the /a/ prefix for authenticated API calls:

   curl -u "your-username:your-http-password" https://your-gerrit-server.com/a/changes/?q=status:open
   

5. Verify Gerrit access permissions for your account

HTTP Credentials Authentication Issues

If you're having trouble with authentication, check your Gerrit config for gitBasicAuthPolicy = HTTP (or HTTP_LDAP).

Working with Self-Signed Certificates

• GERRIT_SSL_VERIFY=false disables TLS verification when Gerrit uses an internally issued certificate lacking required Subject Alternative Name (SAN) entries.
• Provide a custom certificate bundle via GERRIT_CA_BUNDLE=/path/to/ca.pem to keep verification enabled while trusting a private CA.
• Treat disabled verification as a temporary workaround until a certificate with matching SANs is issued for the Gerrit hostnames you access.

License

This project is licensed under the MIT License.

Testing

This project includes comprehensive Docker integration tests using testcontainers-python for reliable cross-platform testing.

Running Tests

To run the full test suite:

# Install development dependencies
pip install -e ".[dev]"

# Run all tests
pytest

# Run only integration tests
pytest -m integration

# Run with verbose output
pytest -v

# Run with coverage
pytest --cov=. --cov-report=html

Test Environment Variables

The following environment variables can be used to configure test behavior:

• TEST_STARTUP_TIMEOUT: Container startup timeout in seconds (default: 30)
• TEST_LOGS_SETTLE_DELAY: Delay before checking logs in seconds (default: 0)
• DOCKER_HOST: Docker daemon host for remote Docker (optional)

Example:

# Run tests with custom timeouts
TEST_STARTUP_TIMEOUT=60 TEST_LOGS_SETTLE_DELAY=1 pytest tests/test_docker_integration.py -v

Docker Requirements

Docker integration tests require:

• Docker daemon running and accessible
• Docker socket available at /var/run/docker.sock (Linux/macOS) or DOCKER_HOST set
• Sufficient permissions to build and run containers

Tests will be automatically skipped if Docker is not available.

CI/CD Integration

For CI/CD environments, ensure:

• Docker-in-Docker (DinD) service is available
• Docker socket is mounted or DOCKER_HOST is configured
• Sufficient timeout values are set for slower environments

Contributing

We welcome contributions! Please:

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Run the test suite to ensure everything works
5. Submit a pull request