framework-migration-assistant

Framework Migration Assistant

Overview

This skill automatically migrates Python web applications between frameworks, transforming code, configuration, and tests while preserving existing functionality. It handles route migration, request/response patterns, dependency injection, configuration updates, and test adaptations, committing changes incrementally with detailed summaries.

Quick Start

Basic Usage

# Navigate to your repository
cd /path/to/your/repo

# Run migration
python scripts/migrate.py . --from flask --to fastapi

The migration process will:

1. Create a migration branch
2. Analyze your codebase
3. Update dependencies
4. Migrate routes and handlers
5. Update configuration
6. Adapt tests
7. Generate a summary report

Example: Flask to FastAPI

# Migrate Flask app to FastAPI
python scripts/migrate.py /path/to/flask-app --from flask --to fastapi

# Output:
# ✓ Created migration branch: migrate-flask-to-fastapi
# ✓ Analyzing codebase...
# ✓ Found 15 route files
# ✓ Found 23 test files
# ✓ Migrating dependencies...
# ✓ Migrating routes...
# ✓ Migrating configuration...
# ✓ Migrating tests...
# ✓ Migration completed successfully!

Supported Migration Paths

Flask → FastAPI

What gets migrated:

• Route decorators: @app.route() → @app.get(), @app.post(), etc.
• Request handling: request.args → query parameters, request.json → Pydantic models
• Response handling: jsonify() → direct return
• Configuration: Flask config → Pydantic Settings
• Tests: Flask test client → FastAPI TestClient
• Dependencies: Flask packages → FastAPI equivalents

Example transformation:

Before (Flask):

@app.route('/users/<int:user_id>', methods=['GET'])
def get_user(user_id):
    user = db.get_user(user_id)
    return jsonify(user)

After (FastAPI):

@app.get('/users/{user_id}')
async def get_user(user_id: int) -> UserSchema:
    user = await db.get_user(user_id)
    return user

Django → FastAPI