Sebastián Ramírez <******@****.***> 1766004103 -0800

Sebastián Ramírez <******@****.***> 1766004103 -0800

Sebastián Ramírez <******@****.***> 1766004103 -0800

Sebastián Ramírez <******@****.***> 1766004103 -0800

{* ../../docs_src/advanced_middleware/tutorial001_py39.py hl[2,6] *}

## `TrustedHostMiddleware` { #trustedhostmiddleware }

Гарантирует, что во всех входящих запросах корректно установлен `Host`‑заголовок, чтобы защититься от атак на HTTP‑заголовок Host.

{* ../../docs_src/advanced_middleware/tutorial002_py39.py hl[2,6:8] *}

Поддерживаются следующие аргументы:

So, you can declare your function as:

{* ../../docs_src/path_params_numeric_validations/tutorial002_py39.py hl[7] *}

But keep in mind that if you use `Annotated`, you won't have this problem, it won't matter as you're not using the function parameter default values for `Query()` or `Path()`.

Por exemplo, para declarar um outro retorno com o status code `404` e um modelo do Pydantic chamado `Message`, você pode escrever:

{* ../../docs_src/additional_responses/tutorial001_py39.py hl[18,22] *}

/// note | Nota

Lembre-se que você deve retornar o `JSONResponse` diretamente.

///

/// info | Informação

A chave `model` não é parte do OpenAPI.

{* ../../docs_src/first_steps/tutorial001_py39.py hl[7] *}

This is a Python function.

It will be called by **FastAPI** whenever it receives a request to the URL "`/`" using a `GET` operation.

In this case, it is an `async` function.

---

You could also define it as a normal function instead of `async def`:

{* ../../docs_src/first_steps/tutorial003_py39.py hl[7] *}

/// note

{* ../../docs_src/first_steps/tutorial003_py39.py hl[7] *}

/// note | Hinweis

Wenn Sie den Unterschied nicht kennen, lesen Sie [Async: *„In Eile?“*](../async.md#in-a-hurry){.internal-link target=_blank}.

///

### Schritt 5: den Inhalt zurückgeben { #step-5-return-the-content }

{* ../../docs_src/first_steps/tutorial001_py39.py hl[8] *}

## Use `HTTPException` { #use-httpexception }

To return HTTP responses with errors to the client you use `HTTPException`.

### Import `HTTPException` { #import-httpexception }

{* ../../docs_src/handling_errors/tutorial001_py39.py hl[1] *}

### Raise an `HTTPException` in your code { #raise-an-httpexception-in-your-code }

`HTTPException` is a normal Python exception with additional data relevant for APIs.