FastAPI is a modern, fast (high-performance), web framework for building APIs with Python. It is designed to be easy to use and highly productive. Here are some key features and concepts of FastAPI:
- Asynchronous Programming: FastAPI is built on top of Python’s async and await features, making it suitable for handling asynchronous operations efficiently. This is especially useful for handling I/O-bound tasks such as database queries or making API calls.
- Automatic Documentation: FastAPI automatically generates interactive documentation for your APIs using the OpenAPI and JSON Schema standards. You can access the documentation at
/docs
or/redoc
endpoints when running your FastAPI application. - Data Validation: FastAPI simplifies data validation by allowing you to define data models using Python’s type hints. It automatically validates incoming request data and converts it to Python objects.
- Dependency Injection: You can use dependency injection to manage the dependencies of your API functions. This makes it easy to handle things like database connections, authentication, and other common tasks.
- Automatic Serialization: FastAPI automatically serializes your Python data models to JSON, making it easy to return data from your API endpoints.
- Security: FastAPI provides built-in security features for common authentication and authorization mechanisms like OAuth2 and JWT.
- Middleware: You can use middleware to add functionality to your application, such as logging, authentication, or request/response modification.
- WebSocket Support: FastAPI also supports WebSocket communication, allowing you to build real-time applications.
Here’s a basic example of creating a FastAPI application:
from fastapi import FastAPI
app = FastAPI()
@app.get("/")
def read_root():
return {"message": "Hello, World!"}
To run this application, you can use uvicorn
(ASGI server):
uvicorn your_app_name:app --reload
Replace your_app_name
with the name of your Python file containing the FastAPI app. The --reload
flag enables auto-reloading during development.
FastAPI’s official documentation is comprehensive and a great resource to learn more: https://fastapi.tiangolo.com/
FastAPI has become very popular in the Python community due to its speed, automatic documentation generation, and ease of use for building APIs.