email_file.write(content)


@app.post("/send-notification/{email}")
async def send_notification(email: str, background_tasks: BackgroundTasks):
    background_tasks.add_task(write_notification, email, message="some notification")

import importlib
import os
from pathlib import Path

import pytest

from ...utils import needs_pydanticv1


# TODO: pv2 add version with Pydantic v2
@needs_pydanticv1
def test_testing_dbs(tmp_path_factory: pytest.TempPathFactory):
    tmp_path = tmp_path_factory.mktemp("data")
    cwd = os.getcwd()
    os.chdir(tmp_path)
    test_db = Path("./test.db")
    if test_db.is_file():  # pragma: nocover
        test_db.unlink()

                    if root_path and self.root_path_in_servers:
                        self.servers.insert(0, {"url": root_path})
                        server_urls.add(root_path)
                return JSONResponse(self.openapi())

            self.add_route(self.openapi_url, openapi, include_in_schema=False)
        if self.openapi_url and self.docs_url:

            async def swagger_ui_html(req: Request) -> HTMLResponse:

```Python hl_lines="6-9"
{!../../../docs_src/background_tasks/tutorial001.py!}
```

## 添加后台任务

在你的 *路径操作函数* 里，用 `.add_task()` 方法将任务函数传到 *后台任务* 对象中：

```Python hl_lines="14"
{!../../../docs_src/background_tasks/tutorial001.py!}
```

`.add_task()` 接收以下参数：

* 在后台运行的任务函数(`write_notification`)。
* 应按顺序传递给任务函数的任意参数序列(`email`)。
* 应传递给任务函数的任意关键字参数(`message="some notification"`)。

## 依赖注入

But if you need to change some of the defaults, support more than one predefined database, work with an async framework (like FastAPI), etc, you will need to add quite some complex extra code to override those defaults.

Nevertheless, it's possible to do it, and here you'll see exactly what code you have to add to be able to use Peewee with FastAPI.

!!! note "Technical Details"

async def get_context_b_bg(tasks: BackgroundTasks, state: dict = Depends(context_b)):
    async def bg(state: dict):
        state["bg"] = f"bg set - b: {state['context_b']} - a: {state['context_a']}"

    tasks.add_task(bg, state)
    return state


# Sync versions


@app.get("/sync_async")
def get_sync_async(state: str = Depends(asyncgen_state)):
    return state


@app.get("/sync_sync")

### Return the error

After detecting that the credentials are incorrect, return an `HTTPException` with a status code 401 (the same returned when no credentials are provided) and add the header `WWW-Authenticate` to make the browser show the login prompt again:

=== "Python 3.9+"

    ```Python hl_lines="26-30"
    {!> ../../../docs_src/security/tutorial007_an_py39.py!}
    ```

from typing_extensions import Annotated, Doc

swagger_ui_default_parameters: Annotated[
    Dict[str, Any],
    Doc(
        """
        Default configurations for Swagger UI.

        You can use it as a template to add any other configurations needed.
        """
    ),
] = {
    "dom_id": "#swagger-ui",
    "layout": "BaseLayout",
    "deepLinking": True,
    "showExtensions": True,
    "showCommonExtensions": True,
}

    title: Introduction to the fastapi python framework
  - author: Nils de Bruin
    author_link: https://medium.com/@nilsdebruin
    link: https://medium.com/data-rebels/fastapi-how-to-add-basic-and-cookie-authentication-a45c85ef47d3
    title: FastAPI — How to add basic and cookie authentication
  - author: Nils de Bruin
    author_link: https://medium.com/@nilsdebruin

@app.api_route("/items/{item_id}", methods=["GET"])
def get_items(item_id: str):
    return {"item_id": item_id}


def get_not_decorated(item_id: str):
    return {"item_id": item_id}


app.add_api_route("/items-not-decorated/{item_id}", get_not_decorated)


@app.delete("/items/{item_id}")
def delete_item(item_id: str, item: Item):
    return {"item_id": item_id, "item": item}