FastAPI Has a Free API — Build Production APIs in Python at Lightning Speed

#python #api #webdev #opensource

FastAPI: The Fastest Python Web Framework

FastAPI is a modern Python framework for building APIs. Auto-generated docs, type validation, async support — it is as fast as Node.js and Go frameworks while being pure Python.

Why FastAPI

Performance — on par with Node.js and Go
Auto docs — Swagger UI and ReDoc generated automatically
Type safety — Pydantic validation built-in
Async — native async/await support
Standards — OpenAPI and JSON Schema compliant

The Free API

from fastapi import FastAPI
from pydantic import BaseModel

app = FastAPI()

class Item(BaseModel):
    name: str
    price: float
    in_stock: bool = True

@app.get("/")
def root():
    return {"message": "Hello World"}

@app.post("/items/")
def create_item(item: Item):
    return {"item": item, "total": item.price * 1.1}

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

pip install fastapi uvicorn
uvicorn main:app --reload
# Docs at http://localhost:8000/docs
# API at http://localhost:8000/openapi.json

Authentication

from fastapi import Depends, HTTPException
from fastapi.security import HTTPBearer

security = HTTPBearer()

@app.get("/protected")
def protected(token = Depends(security)):
    if token.credentials != "secret":
        raise HTTPException(401)
    return {"data": "secret stuff"}

Database with SQLAlchemy

from sqlalchemy import create_engine
from sqlalchemy.orm import Session

engine = create_engine("sqlite:///./app.db")

@app.get("/users/{user_id}")
def get_user(user_id: int):
    with Session(engine) as session:
        user = session.get(User, user_id)
        return user

WebSocket

@app.websocket("/ws")
async def websocket_endpoint(websocket):
    await websocket.accept()
    while True:
        data = await websocket.receive_text()
        await websocket.send_text(f"Echo: {data}")

Real-World Use Case

A data team needed an API for their ML model. FastAPI: 50 lines of code, auto-generated Swagger docs, Pydantic validation, async inference. From Jupyter notebook to production API in one afternoon. Handles 10K requests/sec.

Quick Start

pip install "fastapi[standard]"
fastapi dev main.py

Resources

Need data for your APIs? Check out my scraping tools on Apify or email spinov001@gmail.com for custom solutions.

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