# Body - Вложенные модели { #body-nested-models }

С помощью **FastAPI** вы можете определять, валидировать, документировать и использовать модели произвольной глубины вложенности (благодаря Pydantic).

## Поля-списки { #list-fields }

Вы можете определить атрибут как подтип. Например, Python-тип `list`:

{* ../../docs_src/body_nested_models/tutorial001_py310.py hl[12] *}

from typing import Annotated, Union

import pytest
from dirty_equals import IsOneOf, IsPartialDict
from fastapi import Body, FastAPI
from fastapi.testclient import TestClient
from pydantic import BaseModel, Field

from .utils import get_body_model_name

app = FastAPI()

# =====================================================================================
# Without aliases

from typing import Annotated, Optional

import pytest
from fastapi import Body, FastAPI
from fastapi.testclient import TestClient
from pydantic import BaseModel, Field

from .utils import get_body_model_name

app = FastAPI()

# =====================================================================================
# Without aliases


@app.post("/optional-str", operation_id="optional_str")

import importlib

import pytest
from fastapi.testclient import TestClient

from ...utils import needs_py310


@pytest.fixture(
    name="client",
    params=[
        pytest.param("tutorial004_py39"),
        pytest.param("tutorial004_py310", marks=needs_py310),
    ],
)
def get_client(request: pytest.FixtureRequest):
    mod = importlib.import_module(f"docs_src.query_params.{request.param}")

    client = TestClient(mod.app)

import importlib

import pytest
from fastapi.testclient import TestClient

from ...utils import needs_py310


@pytest.fixture(
    name="client",
    params=[
        pytest.param("tutorial004_py39"),
        pytest.param("tutorial004_py310", marks=needs_py310),
        pytest.param("tutorial004_an_py39"),
        pytest.param("tutorial004_an_py310", marks=needs_py310),
        pytest.param(
            "tutorial004_regex_an_py310",

import importlib

import pytest
from fastapi.testclient import TestClient
from inline_snapshot import snapshot

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.response_model.{request.param}")

import os
from typing import Any

from pdm.backend.hooks import Context

TIANGOLO_BUILD_PACKAGE = os.getenv("TIANGOLO_BUILD_PACKAGE", "fastapi")


def pdm_build_initialize(context: Context) -> None:
    metadata = context.config.metadata
    # Get custom config for the current package, from the env var
    config: dict[str, Any] = context.config.data["tool"]["tiangolo"][
        "_internal-slim-build"
    ]["packages"].get(TIANGOLO_BUILD_PACKAGE)

{* ../../docs_src/query_params/tutorial002_py310.py hl[7] *}

In diesem Fall wird der Funktionsparameter `q` optional und standardmäßig `None` sein.

/// check | Testen

Beachten Sie auch, dass **FastAPI** intelligent genug ist, um zu erkennen, dass `item_id` ein Pfad-Parameter ist und `q` keiner, daher muss letzteres ein Query-Parameter sein.

///

## Query-Parameter Typkonvertierung { #query-parameter-type-conversion }

from fastapi.testclient import TestClient

from docs_src.advanced_middleware.tutorial002_py39 import app


def test_middleware():
    client = TestClient(app, base_url="http://example.com")
    response = client.get("/")
    assert response.status_code == 200, response.text
    client = TestClient(app, base_url="http://subdomain.example.com")
    response = client.get("/")
    assert response.status_code == 200, response.text

from fastapi.testclient import TestClient

from .app import app


def test_recursive():
    client = TestClient(app)
    response = client.get("/items/recursive")
    assert response.status_code == 200, response.text
    assert response.json() == {
        "sub_items": [{"name": "subitem", "sub_items": []}],
        "name": "item",
    }

    response = client.get("/items/recursive-submodel")