Por ejemplo, si el cliente intenta enviar un parámetro query `tool` con un valor de `plumbus`, como:

```http
https://example.com/items/?limit=10&tool=plumbus
```

Recibirán un response de **error** que les indica que el parámetro query `tool` no está permitido:

```json
{
    "detail": [
        {
            "type": "extra_forbidden",

                        <ol class="breadcrumb float-sm-right">
                            <li class="breadcrumb-item"><la:link href="/admin/wizard/">
                                <la:message key="labels.wizard_start_title"/>
                            </la:link></li>
                            <li class="breadcrumb-item active"><la:message
                                    key="labels.wizard_crawling_config_title"/></li>

app = FastAPI()


def test_no_annotated_defaults():
    with pytest.raises(
        AssertionError, match="Path parameters cannot have a default value"
    ):

        @app.get("/items/{item_id}/")
        async def get_item(item_id: Annotated[int, Path(default=1)]):
            pass  # pragma: nocover

    with pytest.raises(
        AssertionError,
        match=(

使用与声明路径和查询参数相同的方式，把它添加至*路径操作*：

{* ../../docs_src/body/tutorial001_py310.py hl[16] *}

...并把其类型声明为你创建的模型 `Item`。

## 结果 { #results }

仅使用这些 Python 类型声明，**FastAPI** 就可以：

* 以 JSON 形式读取请求体。
* （在必要时）把请求体转换为对应的类型。
* 校验数据。
    * 数据无效时返回清晰的错误信息，并指出错误数据的确切位置和内容。
* 把接收的数据赋值给参数 `item`。
    * 因为你把函数中的参数类型声明为 `Item`，所以还能获得所有属性及其类型的编辑器支持（补全等）。
* 为你的模型生成 [JSON Schema](https://json-schema.org) 定义，如果对你的项目有意义，还可以在其他地方使用它们。

        List<String> anchorList;
        if (obj instanceof final String s) {
            anchorList = List.of(s);
        } else if (obj instanceof final List<?> l) {
            anchorList = l.stream().filter(item -> item != null).map(String::valueOf).toList();
        } else {
            return null;
        }

        if (anchorList.isEmpty()) {
            return null;
        }

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that can help with the review process. You should delete these items
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- Have you signed the [contributor license agreement](https://www.elastic.co/contributor-agreement)?

                        <ol class="breadcrumb float-sm-right">
                            <li class="breadcrumb-item"><la:link href="/admin/badword">
                                <la:message key="labels.bad_word_link_list"/>
                            </la:link></li>
                            <li class="breadcrumb-item active"><la:message
                                    key="labels.bad_word_link_details"/></li>
                        </ol>

```JSON hl_lines="22"
{
    "openapi": "3.1.0",
    "info": {
        "title": "FastAPI",
        "version": "0.1.0"
    },
    "paths": {
        "/items/": {
            "get": {
                "summary": "Read Items",
                "operationId": "read_items_items__get",
                "responses": {
                    "200": {
                        "description": "Successful Response",

Wenn der Client beispielsweise versucht, einen `tool` Query-Parameter mit dem Wert `plumbus` zu senden, wie:

```http
https://example.com/items/?limit=10&tool=plumbus
```

erhält er eine **Error-Response**, die ihm mitteilt, dass der Query-Parameter `tool` nicht erlaubt ist:

```json
{
    "detail": [
        {
            "type": "extra_forbidden",

For example, if the client tries to send a `tool` query parameter with a value of `plumbus`, like:

```http
https://example.com/items/?limit=10&tool=plumbus
```

They will receive an **error** response telling them that the query parameter `tool` is not allowed:

```json
{
    "detail": [
        {
            "type": "extra_forbidden",