* "挂载"(Mount) 一个 `StaticFiles()` 实例到一个指定路径。

{* ../../docs_src/static_files/tutorial001.py hl[2,6] *}

/// note | 技术细节

你也可以用 `from starlette.staticfiles import StaticFiles`。

**FastAPI** 提供了和 `starlette.staticfiles` 相同的 `fastapi.staticfiles` ，只是为了方便你，开发者。但它确实来自Starlette。

///

### 什么是"挂载"(Mounting)

"挂载" 表示在特定路径添加一个完全"独立的"应用，然后负责处理所有子路径。

这与使用`APIRouter`不同，因为安装的应用程序是完全独立的。OpenAPI和来自你主应用的文档不会包含已挂载应用的任何东西等等。

Primeiro, você tem que importá-lo:

{* ../../docs_src/body_fields/tutorial001_an_py310.py hl[4] *}

/// warning | Atenção

Note que `Field` é importado diretamente do `pydantic`, não do `fastapi` como todo o resto (`Query`, `Path`, `Body`, etc).

///

## Declare atributos do modelo { #declare-model-attributes }

Você pode então utilizar `Field` com atributos do modelo:

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):

import importlib

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_an_py39"),
        pytest.param("tutorial001_an_py310", marks=needs_py310),
        pytest.param("tutorial001_02_an_py39"),

import importlib
from textwrap import dedent

import pytest
from dirty_equals import IsList
from fastapi.testclient import TestClient

from ...utils import needs_py310

DESCRIPTIONS = {
    "tutorial003": "Create an item with all the information, name, description, price, tax and a set of unique tags",
    "tutorial004": dedent("""
        Create an item with all the information:

        - **name**: each item must have a name

# JSON 兼容编码器

在某些情况下，您可能需要将数据类型（如Pydantic模型）转换为与JSON兼容的数据类型（如`dict`、`list`等）。

比如，如果您需要将其存储在数据库中。

对于这种要求， **FastAPI**提供了`jsonable_encoder()`函数。

## 使用`jsonable_encoder`

让我们假设你有一个数据库名为`fake_db`，它只能接收与JSON兼容的数据。

例如，它不接收`datetime`这类的对象，因为这些对象与JSON不兼容。

因此，`datetime`对象必须将转换为包含<a href="https://en.wikipedia.org/wiki/ISO_8601" class="external-link" target="_blank">ISO格式化</a>的`str`类型对象。

同样，这个数据库也不会接收Pydantic模型（带有属性的对象），而只接收`dict`。

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.body.{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("tutorial002_py39"),
        pytest.param("tutorial002_py310", marks=needs_py310),
        pytest.param("tutorial002_an_py39"),
        pytest.param("tutorial002_an_py310", marks=needs_py310),
        pytest.param("tutorial003_py39"),

import importlib
from types import ModuleType

import pytest
from fastapi.testclient import TestClient

from ...utils import needs_py310


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

import importlib

import pytest
from fastapi.testclient import TestClient


@pytest.fixture(
    name="client",
    params=[
        pytest.param("tutorial004_py39"),
        pytest.param("tutorial004_an_py39"),
    ],
)
def get_client(request: pytest.FixtureRequest) -> TestClient:
    mod = importlib.import_module(
        f"docs_src.path_params_numeric_validations.{request.param}"
    )
    return TestClient(mod.app)