Fastapi | Tutorial Pdf

@app.get("/search/")
def search(q: str, limit: int = 10, sort: str = "asc"):
    return "query": q, "limit": limit, "sort": sort

URL example: /search/?q=fastapi&limit=5&sort=desc

This is where FastAPI truly shines. Pydantic models do more than just define shape – they provide:

from datetime import datetime
from typing import List, Optional
class User(BaseModel):
id: int
name: str
signup_ts: Optional[datetime] = None
friends: List[int] = []
@app.put("/users/user_id")
async def update_user(user_id: int, user: User):
return "user_id": user_id, "user_data": user.dict()
 fastapi tutorial pdf

Any FastAPI tutorial PDF worth its salt will dedicate a full chapter to Pydantic.

Decorate endpoints to document and filter response data. URL example: /search/

from fastapi.responses import JSONResponse
class ResponseModel(BaseModel):
status: str
data: dict
@app.get("/secure-data", response_model=ResponseModel)
async def secure_endpoint():
return "status": "ok", "data": "secret": "value"

The response_model ensures output structure and provides automatic validation.

Parameters that appear after the ? in a URL.

@app.get("/items/")
async def list_items(skip: int = 0, limit: int = 10):
    return "skip": skip, "limit": limit

Request: /items/?skip=5&limit=20 – FastAPI maps skip=5 and limit=20. from datetime import datetime from typing import List,