FastOpenAPI is a library for generating and integrating OpenAPI schemas using Pydantic and various frameworks.

This project was inspired by FastAPI and aims to provide a similar developer-friendly experience.

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📦 Installation

Install only FastOpenAPI:

pip install fastopenapi

Install FastOpenAPI with a specific framework:

pip install fastopenapi[aiohttp]

pip install fastopenapi[falcon]

pip install fastopenapi[flask]

pip install fastopenapi[quart]

pip install fastopenapi[sanic]

pip install fastopenapi[starlette]

pip install fastopenapi[tornado]

pip install fastopenapi[django]

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🛠️ Quick Start

Step 1. Create an application

• Create the main.py file
• Copy the code from an example
• For some examples uvicorn is required (pip install uvicorn)

Examples:

• 

  Click to expand the AioHTTP Example

  fromaiohttpimportwebfrompydanticimportBaseModelfromfastopenapi.routersimportAioHttpRouterapp=web.Application()
  router=AioHttpRouter(app=app)
  classHelloResponse(BaseModel):
  message: str@router.get("/hello", tags=["Hello"], status_code=200, response_model=HelloResponse)asyncdefhello(name: str):
  """Say hello from aiohttp"""returnHelloResponse(message=f"Hello, {name}! It's aiohttp!")
  if__name__=="__main__":
  web.run_app(app, host="127.0.0.1", port=8000)

• 

  Click to expand the Falcon Example

  fromfalconimportAppfrompydanticimportBaseModelfromwsgiref.simple_serverimportmake_serverfromfastopenapi.routersimportFalconRouterapp=App()
  router=FalconRouter(app=app)
  classHelloResponse(BaseModel):
  message: str@router.get("/hello", tags=["Hello"], status_code=200, response_model=HelloResponse)defhello(name: str):
  """Say hello from Falcon"""returnHelloResponse(message=f"Hello, {name}! It's Falcon!")
  if__name__=="__main__":
  withmake_server("", 8000, app) ashttpd:
  print("Serving on port 8000...")
  httpd.serve_forever()

  Click to expand the Falcon Async Example

  importfalcon.asgiimportuvicornfrompydanticimportBaseModelfromfastopenapi.routersimportFalconAsyncRouterapp=falcon.asgi.App()
  router=FalconAsyncRouter(app=app)
  classHelloResponse(BaseModel):
  message: str@router.get("/hello", tags=["Hello"], status_code=200, response_model=HelloResponse)asyncdefhello(name: str):
  """Say hello from Falcon"""returnHelloResponse(message=f"Hello, {name}! It's Falcon!")
  if__name__=="__main__":
  uvicorn.run(app, host="127.0.0.1", port=8000)

• 

  Click to expand the Flask Example

  fromflaskimportFlaskfrompydanticimportBaseModelfromfastopenapi.routersimportFlaskRouterapp=Flask(__name__)
  router=FlaskRouter(app=app)
  classHelloResponse(BaseModel):
  message: str@router.get("/hello", tags=["Hello"], status_code=200, response_model=HelloResponse)defhello(name: str):
  """Say hello from Flask"""returnHelloResponse(message=f"Hello, {name}! It's Flask!")
  if__name__=="__main__":
  app.run(port=8000)

• 

  Click to expand the Quart Example

  frompydanticimportBaseModelfromquartimportQuartfromfastopenapi.routersimportQuartRouterapp=Quart(__name__)
  router=QuartRouter(app=app)
  classHelloResponse(BaseModel):
  message: str@router.get("/hello", tags=["Hello"], status_code=200, response_model=HelloResponse)asyncdefhello(name: str):
  """Say hello from Quart"""returnHelloResponse(message=f"Hello, {name}! It's Quart!")
  if__name__=="__main__":
  app.run(port=8000)

• 

  Click to expand the Sanic Example

  frompydanticimportBaseModelfromsanicimportSanicfromfastopenapi.routersimportSanicRouterapp=Sanic("MySanicApp")
  router=SanicRouter(app=app)
  classHelloResponse(BaseModel):
  message: str@router.get("/hello", tags=["Hello"], status_code=200, response_model=HelloResponse)asyncdefhello(name: str):
  """Say hello from Sanic"""returnHelloResponse(message=f"Hello, {name}! It's Sanic!")
  if__name__=="__main__":
  app.run(host="0.0.0.0", port=8000)

• 

  Click to expand the Starlette Example

  importuvicornfrompydanticimportBaseModelfromstarlette.applicationsimportStarlettefromfastopenapi.routersimportStarletteRouterapp=Starlette()
  router=StarletteRouter(app=app)
  classHelloResponse(BaseModel):
  message: str@router.get("/hello", tags=["Hello"], status_code=200, response_model=HelloResponse)asyncdefhello(name: str):
  """Say hello from Starlette"""returnHelloResponse(message=f"Hello, {name}! It's Starlette!")
  if__name__=="__main__":
  uvicorn.run(app, host="127.0.0.1", port=8000)

• 

  Click to expand the Tornado Example

  importasynciofrompydanticimportBaseModelfromtornado.webimportApplicationfromfastopenapi.routersimportTornadoRouterapp=Application()
  router=TornadoRouter(app=app)
  classHelloResponse(BaseModel):
  message: str@router.get("/hello", tags=["Hello"], status_code=200, response_model=HelloResponse)defhello(name: str):
  """Say hello from Tornado"""returnHelloResponse(message=f"Hello, {name}! It's Tornado!")
  asyncdefmain():
  app.listen(8000)
  awaitasyncio.Event().wait()
  if__name__=="__main__":
  asyncio.run(main())

• 

  Click to expand the Django Example

  fromdjango.confimportsettingsfromdjango.core.managementimportcall_commandfromdjango.core.wsgiimportget_wsgi_applicationfromdjango.urlsimportpathfrompydanticimportBaseModelfromfastopenapi.routersimportDjangoRoutersettings.configure(DEBUG=True, SECRET_KEY="__CHANGEME__", ROOT_URLCONF=__name__)
  application=get_wsgi_application()
  router=DjangoRouter(app=True)
  classHelloResponse(BaseModel):
  message: str@router.get("/hello", tags=["Hello"], status_code=200, response_model=HelloResponse)defhello(name: str):
  """Say hello from django"""returnHelloResponse(message=f"Hello, {name}! It's Django!")
  urlpatterns= [path("", router.urls)]
  if__name__=="__main__":
  call_command("runserver")

Step 2. Run the server

Launch the application:

python main.py

Once launched, the documentation will be available at:

Swagger UI:

http://127.0.0.1:8000/docs

ReDoc UI:

http://127.0.0.1:8000/redoc

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⚙️ Features

• Generate OpenAPI schemas with Pydantic v2.
• Data validation using Pydantic models.
• Supports multiple frameworks: AIOHTTP, Falcon, Flask, Quart, Sanic, Starlette, Tornado, Django.
• Proxy routing provides FastAPI-style routing

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📖 Documentation

Explore the Docs for an overview of FastOpenAPI, its core components, and usage guidelines. The documentation is continuously updated and improved.

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📂 Advanced Examples

Examples of integration and detailed usage for each framework are available in the examples directory.

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📊 Quick & Dirty Benchmarks

Fast but not perfect benchmarks. Check the benchmarks directory for details.

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✅ Development Recommendations

• Use Pydantic models for strict typing and data validation.
• Follow the project structure similar to provided examples for easy scalability.
• Regularly update dependencies and monitor library updates for new features.

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🛠️ Contributing

If you have suggestions or find a bug, please open an issue or create a pull request on GitHub.

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🤝 Acknowledgements

_{Supported by JetBrains under the Open Source Support Program.}

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📄 License

This project is licensed under the terms of the MIT license.