py-openapi-tools

Generate starter code for your API from an OpenAPI v3 file.

Supported frameworks:

• Django REST Framework (DRF)
• FastAPI

Who is this for?

• You have an OpenAPI file and want a quick starting point for a Python web project.
• You’ll get basic serializers/models and view functions you can customize — no OpenAPI internals required.

What gets generated

• DRF
  • serializers.py: one DRF Serializer per schema in your OpenAPI file
  • views.py: API views with request/response serialization and status codes
  • urls.py: url patterns wiring view functions/classes
• FastAPI
  • serializers.py: Pydantic models for request/response bodies and components
  • views.py: FastAPI route handlers using the generated models

All files are auto-formatted (isort + black).

Requirements

• Python 3.13 or newer

Install

Option A: Using uv (recommended)

• Install uv if you don’t have it yet: https://docs.astral.sh/uv/
• In this project folder run: uv sync

Option B: Using pip

• Create/activate a virtual environment
• In this project folder run: pip install -e .

After installation, the CLI py-openapi-tools is available.

Quick start

Try with the provided example spec:

• DRF

  • py-openapi-tools tests/openapi.yaml --framework drf --export-folder out
  • Generated: out/serializers.py, out/views.py, out/urls.py

• FastAPI

  • py-openapi-tools tests/openapi.yaml --framework fastapi --export-folder out
  • Generated: out/serializers.py, out/views.py

You can also run via Python module:

• python -m py_openapi_tools.reader tests/openapi.yaml --framework drf --export-folder out

Using the generated code

• DRF
  • Move or copy generated files into your Django app, e.g. myapp/serializers.py, myapp/views.py, myapp/urls.py
  • Include urls in your project’s urlconf
  • Replace placeholder logic in the views with real code (queries, permissions, etc.)
  • Adjust serializer field types as needed
• FastAPI
  • Import generated models and routes into your FastAPI app
  • Fill in the route implementations

Command options

• --export-folder PATH Write generated files into PATH (defaults to a temporary file preview when omitted)
• --framework [drf|fastapi] Select target framework (default: drf)

Examples

• See the tests/ folder for example OpenAPI files:
  • tests/openapi.yaml
  • tests/openapi_examples.yaml
• Also check examples/ for simple integration sketches.

Troubleshooting

• Command not found / Python mismatch
  • Ensure Python 3.13+: python --version
  • Activate your virtual environment
• "OpenAPI schema file not found"
  • Verify the path to your OpenAPI file
• Import errors or formatting issues
  • Install dependencies with uv sync or pip install -e .

FAQ

• Where are files written?
  • Only to the chosen export folder (or a temporary preview when not specified).
• Is the code production-ready?
  • It’s a starting point. You should adapt view logic, security, and data access for your app.
• Can I re-run the generator?
  • Yes. Running again will overwrite previously generated files in the target location.

Happy building with DRF and FastAPI!