Build an API with Python: The Fastest Way Using FastAPI – Tutorial

FastAPI is a modern, fast (high-performance) web framework for building APIs with Python 3.7+ based on standard Python type hints, and it is one of the fastest Python frameworks available. In this tutorial, we will walk through the process of building an API with FastAPI.

Step 1: Install FastAPI

First, you need to install FastAPI using pip:


pip install fastapi


Step 2: Create a New Python File

Create a new Python file, such as main.py, and import the necessary modules:


import fastapi
import uvicorn


Step 3: Define Your API Endpoints

Define your API endpoints using FastAPI decorators. For example:


app = fastapi.FastAPI()

@app.get("/items/{item_id}")
def read_item(item_id: int, q: str = None):
return {"item_id": item_id, "q": q}


Step 4: Run Your API

You can run your API using the uvicorn server. For example:


uvicorn main:app --reload


Conclusion

FastAPI is a powerful and efficient framework for building APIs with Python. It leverages Python’s type hinting system and asynchronous capabilities to provide high performance and a great developer experience. By following the steps outlined in this tutorial, you can quickly get started with building your API using FastAPI.