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

## Crear un `websocket` { #create-a-websocket }

En tu aplicación de **FastAPI**, crea un `websocket`:

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

/// note | Detalles Técnicos

También podrías usar `from starlette.websockets import WebSocket`.

from fastapi.testclient import TestClient

from docs_src.custom_response.tutorial001b_py39 import app

client = TestClient(app)


def test_get_custom_response():
    response = client.get("/items/")
    assert response.status_code == 200, response.text
    assert response.json() == [{"item_id": "Foo"}]


def test_openapi_schema():
    response = client.get("/openapi.json")
    assert response.status_code == 200, response.text

from unittest.mock import Mock, patch

import pytest
from fastapi import Depends, FastAPI
from fastapi.testclient import TestClient


@pytest.fixture(
    name="module",
    params=[
        "tutorial008_py39",
        # Fails with `NameError: name 'DepA' is not defined`
        pytest.param("tutorial008_an_py39", marks=pytest.mark.xfail),
    ],
)
def get_module(request: pytest.FixtureRequest):

from docs_src.app_testing.tutorial004_py39 import test_read_items


def test_main():

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

Esta é uma função Python.

Ela será chamada pelo **FastAPI** sempre que receber uma requisição para a URL "`/`" usando uma operação `GET`.

Neste caso, é uma função `async`.

---

Você também pode defini-la como uma função normal em vez de `async def`:

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

/// note | Nota

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

Esta es una función de Python.

Será llamada por **FastAPI** cuando reciba un request en la URL "`/`" usando una operación `GET`.

En este caso, es una función `async`.

---

También podrías definirla como una función normal en lugar de `async def`:

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

/// note | Nota

from docs_src.app_testing.tutorial002_py39 import test_read_main, test_websocket


def test_main():
    test_read_main()


def test_ws():

{* ../../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

from fastapi.testclient import TestClient

from docs_src.custom_response.tutorial006c_py39 import app

client = TestClient(app)


def test_redirect_status_code():
    response = client.get("/pydantic", follow_redirects=False)
    assert response.status_code == 302
    assert response.headers["location"] == "https://docs.pydantic.dev/"


def test_openapi_schema():
    response = client.get("/openapi.json")

{* ../../docs_src/background_tasks/tutorial001_py39.py hl[6:9] *}

## Den Hintergrundtask hinzufügen { #add-the-background-task }

Übergeben Sie innerhalb Ihrer *Pfadoperation-Funktion* Ihre Taskfunktion mit der Methode `.add_task()` an das *Hintergrundtasks*-Objekt:

{* ../../docs_src/background_tasks/tutorial001_py39.py hl[14] *}

`.add_task()` erhält als Argumente: