import pytest
from fastapi.testclient import TestClient

from ...utils import needs_py310


@pytest.fixture(
    name="client",
    params=[
        pytest.param("tutorial001_py39"),
        pytest.param("tutorial001_py310", marks=needs_py310),
        pytest.param("tutorial001_01_py39"),
        pytest.param("tutorial001_01_py310", marks=needs_py310),
    ],
)
def get_client(request: pytest.FixtureRequest):

from inline_snapshot import snapshot

from tests.utils import needs_py310


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

from inline_snapshot import snapshot

from tests.utils import needs_py310


@pytest.fixture(
    name="client",
    params=[
        pytest.param("tutorial002_py39"),
        pytest.param("tutorial002_py310", marks=[needs_py310]),
        pytest.param("tutorial002_an_py39"),
        pytest.param("tutorial002_an_py310", marks=[needs_py310]),
    ],
)
def get_client(request: pytest.FixtureRequest):

**FastAPI** allows you to declare additional information and validation for your parameters.

Let's take this application as example:

{* ../../docs_src/query_params_str_validations/tutorial001_py310.py hl[7] *}

The query parameter `q` is of type `str | None`, that means that it's of type `str` but could also be `None`, and indeed, the default value is `None`, so FastAPI will know it's not required.

/// note

import pytest
from fastapi.testclient import TestClient

from tests.utils import needs_py310


@pytest.fixture(
    name="mod",
    params=[
        pytest.param("tutorial001_py39"),
        pytest.param("tutorial001_py310", marks=needs_py310),
    ],
)
def get_mod(request: pytest.FixtureRequest):
    mod = importlib.import_module(f"docs_src.openapi_callbacks.{request.param}")
    return mod


@pytest.fixture(name="client")

В таких случаях вы можете использовать `jsonable_encoder` для преобразования данных перед передачей их в ответ:

{* ../../docs_src/response_directly/tutorial001_py310.py hl[5:6,20:21] *}

/// note | Технические детали

Вы также можете использовать `from starlette.responses import JSONResponse`.

from fastapi.testclient import TestClient

from ...utils import needs_py310


@pytest.fixture(
    name="client",
    params=[
        pytest.param("tutorial006_py39"),
        pytest.param("tutorial006_py310", marks=needs_py310),
    ],
)
def get_client(request: pytest.FixtureRequest):
    mod = importlib.import_module(f"docs_src.body_nested_models.{request.param}")

    client = TestClient(mod.app)
    return client

The exception handler will receive a `Request` and the exception.

{* ../../docs_src/handling_errors/tutorial004_py39.py hl[2,14:19] *}

Now, if you go to `/items/foo`, instead of getting the default JSON error with:

```JSON
{
    "detail": [
        {
            "loc": [
                "path",

import pytest
from fastapi.testclient import TestClient

from ...utils import needs_py310


@pytest.fixture(
    name="client",
    params=[
        pytest.param("tutorial006c_py39"),
        pytest.param("tutorial006c_py310", marks=needs_py310),
        pytest.param("tutorial006c_an_py39"),
        pytest.param("tutorial006c_an_py310", marks=needs_py310),
    ],
)
def get_client(request: pytest.FixtureRequest):

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),
        pytest.param("tutorial003_an_py39"),
        pytest.param("tutorial003_an_py310", marks=needs_py310),
    ],
)
def get_client(request: pytest.FixtureRequest):