fw-gear

fw-gear is a Python package maintained by Flywheel that simplifies the development of Flywheel gears. It provides a comprehensive toolkit for interacting with gear runtime objects, managing inputs/outputs, and integrating with the Flywheel platform.

Note: The fw-gear package is the successor to the older flywheel-gear-toolkit package. New gear development should use fw-gear.

Features

• GearContext: Context manager for gear lifecycle management
  • Access configuration values and input files
  • Manage output files and directories
  • Write metadata without SDK authentication
  • Configure logging
• SDK Integration: Automatic Flywheel SDK client instantiation when API key provided
• Metadata Management: Update container and file metadata via .metadata.json
• Utilities: Command execution, ZIP management, resource monitoring, and more
• Nipype Integration: Generate Nipype interfaces from gear manifests

Installation

Basic Installation

pip install fw-gear

With Optional Dependencies

Install specific extras for additional functionality:

# Install with SDK support
pip install fw-gear[sdk]

# Install with all extras (SDK, Nipype, NumPy, psutil)
pip install fw-gear[all]

Available extras:

• sdk: Flywheel SDK integration
• nipype: Nipype workflow integration
• numpy: NumPy array support
• monitoring: Resource monitoring with psutil
• all: All optional dependencies

Quick Start

Create a simple gear in run.py:

from fw_gear.context import GearContext

def main(context):
    # Get configuration
    greeting = context.config.opts.get("greeting", "Hello")

    # Get input file
    input_file = context.config.get_input_path("input_file")

    # Write output
    with context.open_output("output.txt", "w") as f:
        f.write(f"{greeting} from {input_file}\n")

if __name__ == "__main__":
    with GearContext() as context:
        context.init_logging()
        main(context)

Documentation

Comprehensive documentation is available at: https://flywheel-io.gitlab.io/scientific-solutions/lib/fw-gear/

• Getting Started - Tutorial with practical examples
• GearContext Guide - Detailed usage guide
• Utils Module - Helper utilities
• API Reference - Complete API documentation
• Migration Guide - Migrating from flywheel-gear-toolkit

Contributing

We welcome contributions! Please see CONTRIBUTING.md for guidelines on contributing.

License

fw-gear is released under the MIT License.

Support

• Documentation: https://flywheel-io.gitlab.io/scientific-solutions/lib/fw-gear/
• Issues: GitLab Issue Tracker
• Flywheel Docs: https://docs.flywheel.io/