But it's the simplest way to focus on the server-side of WebSockets and have a working example:

{* ../../docs_src/websockets/tutorial001_py39.py hl[2,6:38,41:43] *}

## Create a `websocket` { #create-a-websocket }

In your **FastAPI** application, create a `websocket`:

{* ../../docs_src/websockets/tutorial001_py39.py hl[1,46:47] *}

/// note | Technical Details

You could also use `from starlette.websockets import WebSocket`.

{* ../../docs_src/websockets/tutorial001_py39.py hl[2,6:38,41:43] *}

## Einen `websocket` erstellen { #create-a-websocket }

Erstellen Sie in Ihrer **FastAPI**-Anwendung einen `websocket`:

{* ../../docs_src/websockets/tutorial001_py39.py hl[1,46:47] *}

/// note | Technische Details

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

## `TrustedHostMiddleware` { #trustedhostmiddleware }

Garante que todas as requisições recebidas tenham um cabeçalho `Host` corretamente configurado, a fim de proteger contra ataques de cabeçalho de host HTTP.

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

Os seguintes argumentos são suportados:

{* ../../docs_src/path_operation_advanced_configuration/tutorial003_py39.py hl[6] *}

## Descripción avanzada desde el docstring { #advanced-description-from-docstring }

Puedes limitar las líneas usadas del docstring de una *path operation function* para OpenAPI.

{* ../../docs_src/path_operation_advanced_configuration/tutorial003_py39.py hl[6] *}

## Descrição avançada a partir de docstring { #advanced-description-from-docstring }

Você pode limitar as linhas utilizadas a partir de uma docstring de uma *função de operação de rota* para o OpenAPI.

import importlib

import pytest
from fastapi.testclient import TestClient

from ...utils import needs_py310


@pytest.fixture(
    name="client",
    params=[
        pytest.param("tutorial003_py39"),
        pytest.param("tutorial003_py310", marks=needs_py310),
    ],
)
def get_client(request: pytest.FixtureRequest):
    mod = importlib.import_module(f"docs_src.dataclasses_.{request.param}")

    client = TestClient(mod.app)

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

### Better with `Annotated` { #better-with-annotated }

E um retorno com o código de status `200` que utiliza o seu `response_model`, porém inclui um `example` customizado:

{* ../../docs_src/additional_responses/tutorial003_py39.py hl[20:31] *}

Isso será combinado e incluído em seu OpenAPI, e disponibilizado na documentação da sua API:

<img src="/img/tutorial/additional-responses/image01.png">

{* ../../docs_src/python_types/tutorial003_py39.py hl[1] *}

Because the editor knows the types of the variables, you don't only get completion, you also get error checks:

<img src="/img/python-types/image04.png">

Now you know that you have to fix it, convert `age` to a string with `str(age)`:

{* ../../docs_src/python_types/tutorial004_py39.py hl[2] *}

## Declaring types { #declaring-types }

from fastapi.testclient import TestClient
from inline_snapshot import snapshot

from tests.utils import needs_py310


@pytest.fixture(
    name="client",
    params=[
        pytest.param("tutorial003_py39"),
        pytest.param("tutorial003_py310", marks=needs_py310),
        pytest.param("tutorial003_an_py39"),
        pytest.param("tutorial003_an_py310", marks=needs_py310),
    ],
)
def get_client(request: pytest.FixtureRequest):