7 - Body: Fields

You can declare validation and metadata inside of Pydantic models using Field.

from pydantic import BaseModel, Field

class Item(BaseModel):
    name: str
    description: str | None = Field(
        default=None, title="The description of the item", max_length=300
    )
    price: float = Field(gt=0, description="The price must be greater than zero")
    tax: float | None = None

@app.put("/items11/{item_id}")
async def update_item(item_id: int, item: Annotated[Item, Body(embed=True)]):
    results = {"item_id": item_id, "item": item}
    return results

import requests
url = 'http://127.0.0.1:8000'

json_data = {
    'item': {
        'name': 'Pokeball',
        'description': 'A capsule used for capturing Pokemon.',
        'price': 1.50,
        'tax': 0.50
    }
}
requests.put(url + '/items11/123', json=json_data).json()

{'item_id': 123,
 'item': {'name': 'Pokeball',
  'description': 'A capsule used for capturing Pokemon.',
  'price': 1.5,
  'tax': 0.5}}