### 提供 `root_path`

为此，要以如下方式使用命令行选项 `--root-path`：

<div class="termy">

```console
$ uvicorn main:app --root-path /api/v1

<span style="color: green;">INFO</span>:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)
```

</div>

Hypercorn 也支持 `--root-path `选项。

/// note | 技术细节

ASGI 规范定义的 `root_path` 就是为了这种用例。

并且 `--root-path` 命令行选项支持 `root_path`。

///

from typing import Annotated

from fastapi import FastAPI, Path

app = FastAPI()


@app.get("/items/{item_id}")
async def read_items(
    q: str, item_id: Annotated[int, Path(title="The ID of the item to get")]
):
    results = {"item_id": item_id}
    if q:
        results.update({"q": q})

from typing import Annotated

from fastapi import FastAPI, Path

app = FastAPI()


@app.get("/items/{item_id}")
async def read_items(
    item_id: Annotated[int, Path(title="The ID of the item to get")], q: str
):
    results = {"item_id": item_id}
    if q:
        results.update({"q": q})

# Body - Campos { #body-fields }

De la misma manera que puedes declarar validaciones adicionales y metadatos en los parámetros de las *path operation function* con `Query`, `Path` y `Body`, puedes declarar validaciones y metadatos dentro de los modelos de Pydantic usando `Field` de Pydantic.

## Importar `Field` { #import-field }

Primero, tienes que importarlo:

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

/// warning | Advertencia

These are the special functions that you can put in *path operation function* parameters or dependency functions with `Annotated` to get data from the request.

It includes:

* `Query()`
* `Path()`
* `Body()`
* `Cookie()`
* `Header()`
* `Form()`
* `File()`

You can import them all directly from `fastapi`:

```python
from fastapi import Body, Cookie, File, Form, Header, Path, Query
```

::: fastapi.Query

"Montar" significa añadir una aplicación completamente "independiente" en un path específico, que luego se encarga de manejar todo bajo ese path, con las _path operations_ declaradas en esa sub-aplicación.

### Aplicación de nivel superior { #top-level-application }

Primero, crea la aplicación principal de nivel superior de **FastAPI**, y sus *path operations*:

{* ../../docs_src/sub_applications/tutorial001_py39.py hl[3, 6:8] *}

        /**
         * Create a new change notification handle
         *
         * @param path directory path
         * @param key lease key
         * @param dir directory file
         */
        public ChangeNotificationHandle(String path, Smb2LeaseKey key, SmbFile dir) {
            this.directoryPath = path;
            this.leaseKey = key;
            this.directoryFile = dir;
            this.active = true;

                        final Path path = Paths.get(LaServletContextUtil.getServletContext().getRealPath(key));
                        if (Files.isRegularFile(path)) {
                            return Files.getLastModifiedTime(path).toMillis();
                        }
                    } catch (final Exception e) {
                        logger.debug("Failed to access resource file: path={}", key, e);
                    }

		}
	}
}

func newLocalXLStorage(path string) (*xlStorage, error) {
	return newLocalXLStorageWithDiskIdx(path, 0)
}

// Initialize a new storage disk.
func newLocalXLStorageWithDiskIdx(path string, diskIdx int) (*xlStorage, error) {
	u := url.URL{Path: path}
	return newXLStorage(Endpoint{
		URL:     &u,
		IsLocal: true,
		PoolIdx: 0,
		SetIdx:  0,

     * @param path The path to match.
     * @return The matching FtpAuthentication object, or null if no match is found.
     */
    public FtpAuthentication get(final String path) {
        if (path == null) {
            return null;
        }

        for (final FtpAuthentication auth : authenticationList) {
            if (auth.matches(path)) {
                return auth;