Introduction to FastAPI

FastAPI is a modern, fast (high-performance), web framework for building APIs with Python 3.7+ based on standard Python type hints. The key features of FastAPI are:

• Automatic generation of OpenAPI and JSON Schema documentation.
• Asynchronous request handling for improved performance.
• Validation and serialization of request and response data.
• Dependency injection system.

To install FastAPI, you can use pip. Additionally, you may also want to install an ASGI server, such as uvicorn, to run your application.

pip install fastapi uvicorn

FastAPI comes with several features that enhance API development:

• Fast performance: One of the fastest Python frameworks available.
• Easy to use: Designed to be easy to learn and use.
• Robust: Based on standard Python type hints, leading to fewer bugs.
• Highly customizable: Support for middleware, authentication, and more.

Let’s create a simple API with FastAPI:

from fastapi import FastAPI

app = FastAPI()

@app.get("/")
async def read_root():
    return {"Hello": "World"}

if __name__ == "__main__":
    import uvicorn
    uvicorn.run(app, host="127.0.0.1", port=8000)

Here are some best practices to consider when working with FastAPI:

• Use Pydantic models for data validation and serialization.
• Organize your code into routers to keep the application modular.
• Utilize dependency injection to manage shared resources.
• Document your API using the built-in OpenAPI documentation.