* Conversión de datos
* Validación de datos
* Documentación automática

## Tipos especiales y validación { #special-types-and-validation }

Además de tipos singulares normales como `str`, `int`, `float`, etc., puedes usar tipos singulares más complejos que heredan de `str`.

app = FastAPI()


@app.get("/hidden_cookie")
async def hidden_cookie(
    hidden_cookie: Optional[str] = Cookie(default=None, include_in_schema=False),
):
    return {"hidden_cookie": hidden_cookie}


@app.get("/hidden_header")
async def hidden_header(
    hidden_header: Optional[str] = Header(default=None, include_in_schema=False),
):
    return {"hidden_header": hidden_header}

### 添加类型

让我们来修改上面例子的一行代码。

我们将把下面这段代码中的函数参数从：

```Python
    first_name, last_name
```

改成：

```Python
    first_name: str, last_name: str
```

就是这样。

这些就是"类型提示"：

{* ../../docs_src/python_types/tutorial002.py hl[1] *}


这和声明默认值是不同的，例如：

```Python
    first_name="john", last_name="doe"
```

这两者不一样。

    // Or, more simply, check the format of the string.
    @Test
    void testToStringFormat() {
        String str = response.toString();
        assert (str.startsWith("TransTransactNamedPipeResponse["));
        assert (str.endsWith("]"));
    }
}

// We need to add a helper method to TransTransactNamedPipeResponse to make the test more precise

from pydantic import BaseModel

app = FastAPI()


class JsonApiResponse(JSONResponse):
    media_type = "application/vnd.api+json"


class Error(BaseModel):
    status: str
    title: str


class JsonApiError(BaseModel):
    errors: list[Error]


@app.get(
    "/a",
    response_class=Response,
    responses={500: {"description": "Error", "model": JsonApiError}},
)

from pydantic import BaseModel

app = FastAPI()

oid = OpenIdConnect(
    openIdConnectUrl="/openid", description="OpenIdConnect security scheme"
)


class User(BaseModel):
    username: str


def get_current_user(oauth_header: str = Security(oid)):
    user = User(username=oauth_header)
    return user


@app.get("/users/me")
def read_current_user(current_user: User = Depends(get_current_user)):
    return current_user

from fastapi.testclient import TestClient
from pydantic import BaseModel

app = FastAPI()

api_key = APIKeyQuery(name="key", auto_error=False)


class User(BaseModel):
    username: str


def get_current_user(oauth_header: Optional[str] = Security(api_key)):
    if oauth_header is None:
        return None
    user = User(username=oauth_header)
    return user


@app.get("/users/me")

from fastapi.testclient import TestClient
from pydantic import BaseModel

app = FastAPI()

api_key = APIKeyCookie(name="key", auto_error=False)


class User(BaseModel):
    username: str


def get_current_user(oauth_header: Optional[str] = Security(api_key)):
    if oauth_header is None:
        return None
    user = User(username=oauth_header)
    return user


@app.get("/users/me")

from sqlmodel import Field, Session, SQLModel, create_engine, select


class Hero(SQLModel, table=True):
    id: Union[int, None] = Field(default=None, primary_key=True)
    name: str = Field(index=True)
    age: Union[int, None] = Field(default=None, index=True)
    secret_name: str


sqlite_file_name = "database.db"
sqlite_url = f"sqlite:///{sqlite_file_name}"

connect_args = {"check_same_thread": False}

        HandleInfo info = new HandleInfo("/test/file.txt", testGuid, testFileId, HandleType.PERSISTENT, 0, testLeaseKey);

        String str = info.toString();
        assertTrue(str.contains("/test/file.txt"));
        assertTrue(str.contains("PERSISTENT"));
        assertTrue(str.contains(testGuid.toString()));
    }