Sebastián Ramírez <******@****.***> 1679142599 +0100

        use_kwargs = {k: v for k, v in kwargs.items() if v is not _Unset}

        super().__init__(**use_kwargs)

    def __repr__(self) -> str:
        return f"{self.__class__.__name__}({self.default})"


class Path(Param):
    in_ = ParamTypes.path

    def __init__(
        self,
        default: Any = ...,
        *,

    group and organize permissions, you could do it as well in your application, just
    know that that it is application specific, it's not part of the specification.
    """

    def __init__(
        self,
        *,
        grant_type: Annotated[
            Union[str, None],
            Form(pattern="password"),
            Doc(
                """

```
.
├── app
│   ├── __init__.py
│   └── main.py
```

In the file `main.py` you have your **FastAPI** app:


```Python
{!../../../docs_src/app_testing/main.py!}
```

### Testing file

Then you could have a file `test_main.py` with your tests. It could live on the same Python package (the same directory with a `__init__.py` file):

``` hl_lines="5"
.
├── app

{!../../../docs_src/dependencies/tutorial011.py!}
```

本例中，**FastAPI**  使用 `__call__` 检查附加参数及子依赖项，稍后，还要调用它向*路径操作函数*传递值。

## 参数化实例

接下来，使用 `__init__` 声明用于**参数化**依赖项的实例参数：

```Python hl_lines="7"
{!../../../docs_src/dependencies/tutorial011.py!}
```

本例中，**FastAPI** 不使用 `__init__`，我们要直接在代码中使用。

## 创建实例

使用以下代码创建类实例：

```Python hl_lines="16"
{!../../../docs_src/dependencies/tutorial011.py!}
```

        str,
        Doc(
            """
            The HTTP authorization credentials extracted from the header value.
            """
        ),
    ]


class HTTPBase(SecurityBase):
    def __init__(
        self,
        *,
        scheme: str,
        scheme_name: Optional[str] = None,
        description: Optional[str] = None,
        auto_error: bool = True,
    ):

## 🔗 👐

& 🔜, 👥 💪 ⚙️ `__init__` 📣 🔢 👐 👈 👥 💪 ⚙️ "🔗" 🔗:

```Python hl_lines="7"
{!../../../docs_src/dependencies/tutorial011.py!}
```

👉 💼, **FastAPI** 🏆 🚫 ⏱ 👆 ⚖️ 💅 🔃 `__init__`, 👥 🔜 ⚙️ ⚫️ 🔗 👆 📟.

## ✍ 👐

👥 💪 ✍ 👐 👉 🎓 ⏮️:

```Python hl_lines="16"

from fastapi import Depends, FastAPI

app = FastAPI()


fake_items_db = [{"item_name": "Foo"}, {"item_name": "Bar"}, {"item_name": "Baz"}]


class CommonQueryParams:
    def __init__(self, q: str | None = None, skip: int = 0, limit: int = 100):
        self.q = q
        self.skip = skip
        self.limit = limit


@app.get("/items/")
async def read_items(commons: Annotated[Any, Depends(CommonQueryParams)]):

from typing_extensions import Annotated

app = FastAPI()


fake_items_db = [{"item_name": "Foo"}, {"item_name": "Bar"}, {"item_name": "Baz"}]


class CommonQueryParams:
    def __init__(self, q: Union[str, None] = None, skip: int = 0, limit: int = 100):
        self.q = q
        self.skip = skip
        self.limit = limit


@app.get("/items/")
async def read_items(commons: Annotated[Any, Depends(CommonQueryParams)]):

We create a new file at `sql_app/tests/test_sql_app.py`.

So the new file structure looks like:

``` hl_lines="9-11"
.
└── sql_app
    ├── __init__.py
    ├── crud.py
    ├── database.py
    ├── main.py
    ├── models.py
    ├── schemas.py
    └── tests
        ├── __init__.py
        └── test_sql_app.py
```

## Create the new database session

First, we create a new database session with the new database.