Connexion

Connexion Python Framework

Connexion is a contract-first Python web framework that loads an OpenAPI specification and routes requests to Python handlers based on operationId. It performs request validation, parameter parsing, and response validation against the specification, with first-class support for security schemes and Swagger UI.

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API entry from apis.yml

aid: connexion:framework
name: Connexion Python Framework
description: Connexion is a contract-first Python web framework that loads an OpenAPI specification and
  routes requests to Python handlers based on operationId. It performs request validation, parameter parsing,
  and response validation against the specification, with first-class support for security schemes and
  Swagger UI.
humanURL: https://connexion.readthedocs.io/en/latest/
baseURL: https://connexion.readthedocs.io
tags:
- Framework
- OpenAPI
- Python
- Validation
properties:
- type: Documentation
  url: https://connexion.readthedocs.io/en/latest/
- type: Documentation
  url: https://connexion.readthedocs.io/en/latest/quickstart.html
- type: GitHubRepository
  url: https://github.com/spec-first/connexion
- type: License
  url: https://github.com/spec-first/connexion/blob/main/LICENSE
- type: Issue Tracker
  url: https://github.com/spec-first/connexion/issues
x-features:
- AsyncApp, FlaskApp, and ConnexionMiddleware entry points
- Native ASGI server support and Flask compatibility
- Automatic routing from operationId via RestyResolver
- Request and response validation against OpenAPI
- Security middleware honoring OpenAPI security schemes
- Swagger UI mounted from the framework
- Pythonic snake_case parameter conversion
- Strict parameter validation modes
x-useCases:
- Build Python APIs from an OpenAPI 3.x specification
- Migrate Flask applications to a contract-first model
- Add request and response validation to an existing ASGI app
- Generate Swagger UI alongside your API automatically
- Compose multiple OpenAPI specifications under a single app