from fastapi import FastAPI from pydantic import BaseModel
FROM python:3.11 WORKDIR /app COPY requirements.txt . RUN pip install --no-cache-dir -r requirements.txt COPY . . CMD ["uvicorn", "main:app", "--host", "0.0.0.0", "--port", "8000"]
from fastapi import FastAPI # Initialize the FastAPI application app = FastAPI( title="FastAPI PDF Tutorial API", description="A sample API built for our comprehensive FastAPI guide.", version="1.0.0" ) @app.get("/") def read_root(): return "message": "Welcome to the FastAPI Tutorial!" @app.get("/items/item_id") def read_item(item_id: int, q: str = None): return "item_id": item_id, "query": q Use code with caution. Running the Application Start your development server by running: fastapi dev main.py Use code with caution. (Alternatively, you can use: uvicorn main:app --reload )
. ├── database.py ├── models.py ├── schemas.py ├── crud.py └── main.py fastapi tutorial pdf
@app.post("/items/", status_code=status.HTTP_201_CREATED) def create_item(item: Item): return item
Run: pytest -v
from pydantic import BaseModel, Field class InventoryItem(BaseModel): name: str = Field(..., example="Wireless Mouse") description: str = Field(None, max_length=300) price: float = Field(..., gt=0, description="The price must be greater than zero") tax: float = None @app.post("/items/") async def create_item(item: InventoryItem): item_dict = item.dict() if item.tax: price_with_tax = item.price + item.tax item_dict.update("price_with_tax": price_with_tax) return item_dict Use code with caution. 5. Standard Responses and Error Handling from fastapi import FastAPI from pydantic import BaseModel
from fastapi import FastAPI
You can convert this rich website into an offline reference using browser "Save as PDF" features, though the live version's interactive elements are invaluable.
from fastapi import Header, HTTPException async def verify_token(x_token: str = Header(...)): if x_token != "super-secret-token": raise HTTPException(status_code=400, detail="X-Token header invalid") return x_token @app.get("/protected-data/", dependencies=[Depends(verify_token)]) def get_protected_data(): return "data": "This is highly secured information." Use code with caution. 8. Authentication and Security (JWT) CMD ["uvicorn", "main:app", "--host", "0
from fastapi import Depends, HTTPException from sqlalchemy.orm import Session from .database import engine, get_db from .models import DBProduct, Base # Create tables on startup Base.metadata.create_all(bind=engine) @app.get("/db-products/product_id") def fetch_product(product_id: int, db: Session = Depends(get_db)): product = db.query(DBProduct).filter(DBProduct.id == product_id).first() if not product: raise HTTPException(status_code=404, detail="Product not found") return "id": product.id, "title": product.title, "cost": product.cost Use code with caution. Dependency Injection System
: It drives both validation and documentation generation. Utilize Pydantic : Never parse raw JSON bodies manually.
Used for identifying specific resources (e.g., /users/5 ).
FastAPI is a modern, fast (high-performance), web framework for building APIs with Python 3.7+ based on standard Python type hints. In this tutorial, we'll explore the basics of FastAPI and build a simple API to demonstrate its capabilities.