from typing import Union

from fastapi import FastAPI
from pydantic import BaseModel as BaseModelV2
from pydantic.v1 import BaseModel


class Item(BaseModel):
    name: str
    description: Union[str, None] = None
    size: float


class ItemV2(BaseModelV2):
    name: str
    description: Union[str, None] = None
    size: float


app = FastAPI()


@app.post("/items/", response_model=ItemV2)

from typing import Annotated, Literal

from fastapi import FastAPI, Query
from pydantic import BaseModel, Field

app = FastAPI()


class FilterParams(BaseModel):
    model_config = {"extra": "forbid"}

    limit: int = Field(100, gt=0, le=100)
    offset: int = Field(0, ge=0)
    order_by: Literal["created_at", "updated_at"] = "created_at"
    tags: list[str] = []


@app.get("/items/")

from fastapi import FastAPI, File, UploadFile

app = FastAPI()


@app.post("/files/")
async def create_file(file: bytes | None = File(default=None)):
    if not file:
        return {"message": "No file sent"}
    else:
        return {"file_size": len(file)}


@app.post("/uploadfile/")
async def create_upload_file(file: UploadFile | None = None):
    if not file:
        return {"message": "No upload file sent"}
    else:

Si tienes un caso de uso diferente que necesite salir temprano desde una dependencia con `yield`, por favor crea una <a href="https://github.com/fastapi/fastapi/discussions/new?category=questions" class="external-link" target="_blank">Pregunta de Discusión en GitHub</a> con tu caso de uso específico y por qué te beneficiaría tener cierre temprano para dependencias con `yield`.

{* ../../docs_src/response_model/tutorial003.py hl[22] *}

そのため、**FastAPI** は出力モデルで宣言されていない全てのデータをフィルタリングしてくれます（Pydanticを使用）。

## ドキュメントを見る

自動ドキュメントを見ると、入力モデルと出力モデルがそれぞれ独自のJSON Schemaを持っていることが確認できます。

<img src="https://fastapi.tiangolo.com/img/tutorial/response-model/image01.png">

そして、両方のモデルは、対話型のAPIドキュメントに使用されます:

<img src="https://fastapi.tiangolo.com/img/tutorial/response-model/image02.png">

## レスポンスモデルのエンコーディングパラメータ

from typing import Annotated

from fastapi import Depends, FastAPI, HTTPException, status
from fastapi.security import OAuth2PasswordBearer, OAuth2PasswordRequestForm
from pydantic import BaseModel

fake_users_db = {
    "johndoe": {
        "username": "johndoe",
        "full_name": "John Doe",
        "email": "******@****.***",
        "hashed_password": "fakehashedsecret",
        "disabled": False,
    },
    "alice": {

## Usa `CORSMiddleware` { #use-corsmiddleware }

Puedes configurarlo en tu aplicación **FastAPI** usando el `CORSMiddleware`.

* Importa `CORSMiddleware`.
* Crea una lista de orígenes permitidos (como strings).
* Agrégalo como un "middleware" a tu aplicación **FastAPI**.

También puedes especificar si tu backend permite:

* Credenciales (headers de autorización, cookies, etc).

from typing import Annotated

import pytest
from dirty_equals import AnyThing, IsOneOf, IsPartialDict
from fastapi import FastAPI, Header
from fastapi.testclient import TestClient
from pydantic import BaseModel, Field

app = FastAPI()

# =====================================================================================
# Without aliases


@app.get("/required-str")
async def read_required_str(p: Annotated[str, Header()]):

from typing import Union

from fastapi import FastAPI
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    description: Union[str, None] = None
    price: float
    tax: Union[float, None] = None


class User(BaseModel):
    username: str
    full_name: Union[str, None] = None


@app.put("/items/{item_id}")
async def update_item(item_id: int, item: Item, user: User):

from datetime import datetime, time, timedelta
from uuid import UUID

from fastapi import Body, FastAPI

app = FastAPI()


@app.put("/items/{item_id}")
async def read_items(
    item_id: UUID,
    start_datetime: datetime = Body(),
    end_datetime: datetime = Body(),
    process_after: timedelta = Body(),
    repeat_at: time | None = Body(default=None),
):
    start_process = start_datetime + process_after