Projeniz için ilginç ve yararlı görünen bir şey varsa devam edin ve inceleyin, aksi halde bunları atlayabilirsiniz.

/// tip | İpucu

**FastAPI**'ı düzgün (ve önerilen) şekilde öğrenmek istiyorsanız [Öğretici - Kullanıcı Rehberi](../tutorial/index.md){.internal-link target=_blank}'ni bölüm bölüm okuyun.

# Middleware { #middleware }

You can add middleware to **FastAPI** applications.

A "middleware" is a function that works with every **request** before it is processed by any specific *path operation*. And also with every **response** before returning it.

* It takes each **request** that comes to your application.
* It can then do something to that **request** or run any needed code.

This will help us inside of the function with all the completion and type checks.

/// tip

You might remember that request bodies are also declared with Pydantic models.

Here **FastAPI** won't get confused because you are using `Depends`.

///

/// check

The way this dependency system is designed allows us to have different dependencies (different "dependables") that all return a `User` model.

/// tip | Tipp

Sie erinnern sich vielleicht, dass <abbr title="Anfragekörper">Requestbodys</abbr> ebenfalls mit Pydantic-Modellen deklariert werden.

Weil Sie `Depends` verwenden, wird **FastAPI** hier aber nicht verwirrt.

///

/// check | Testen

В таком случае вы можете отключить эту функциональность в FastAPI с помощью параметра `separate_input_output_schemas=False`.

/// info | Информация

Поддержка `separate_input_output_schemas` появилась в FastAPI `0.102.0`. 🤓

///

{* ../../docs_src/separate_openapi_schemas/tutorial002_py310.py hl[10] *}

from typing import Optional, Union

import pytest
from fastapi.openapi.models import Schema, SchemaType


@pytest.mark.parametrize(
    "type_value",
    [
        "array",
        ["string", "null"],
        None,
    ],
)
def test_allowed_schema_type(
    type_value: Optional[Union[SchemaType, list[SchemaType]]],
) -> None:
    """Test that Schema accepts SchemaType, List[SchemaType] and None for type field."""

Если что-то кажется интересным и полезным для вашего проекта, смело изучайте; в противном случае, вероятно, можно просто пропустить.

/// tip | Совет

Если вы хотите изучить FastAPI структурированно (рекомендуется), вместо этого читайте [Учебник — Руководство пользователя](../tutorial/index.md){.internal-link target=_blank} по главам.

                    ],
                    "title": "ValidationError",
                    "type": "object",
                },
            },
        },
        "info": {
            "title": "FastAPI",
            "version": "0.1.0",
        },
        "openapi": "3.1.0",
        "paths": {
            "/items/": {
                "get": {
                    "operationId": "get_items",

Si algo parece interesante y útil para tu proyecto, adelante y revísalo, pero de lo contrario, probablemente puedas simplemente omitirlas.

/// tip | Consejo

Si quieres **aprender FastAPI** de una manera estructurada (recomendado), ve y lee el [Tutorial - Guía de Usuario](../tutorial/index.md){.internal-link target=_blank} capítulo por capítulo en su lugar.

import importlib

import pytest
from fastapi.testclient import TestClient

from ...utils import needs_py310


@pytest.fixture(
    name="client",
    params=[
        "tutorial001_py39",
        pytest.param("tutorial001_py310", marks=needs_py310),
        "tutorial001_an_py39",
        pytest.param("tutorial001_an_py310", marks=needs_py310),
    ],
)
def get_client(request: pytest.FixtureRequest):