background task itself, and use internally only data that doesn't depend on the resources of dependencies with `yield`.

For example, instead of using the same database session, you would create a new database session inside of the background task, and you would obtain the objects from the database using this new session. And then instead of passing the object from the database as a parameter to the background task function, you would pass the ID of that object and then obtain the object again...

import importlib
import os
from pathlib import Path

import pytest

from ...utils import needs_py39, needs_pydanticv1


@needs_py39
# TODO: pv2 add version with Pydantic v2
@needs_pydanticv1
def test_testing_dbs_py39(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

        ("/items", {"ads_id": "ads_track"}, 200, {"ads_id": "ads_track"}),
        (
            "/items",
            {"ads_id": "ads_track", "session": "cookiesession"},
            200,
            {"ads_id": "ads_track"},
        ),
        ("/items", {"session": "cookiesession"}, 200, {"ads_id": None}),
    ],
)
def test(path, cookies, expected_status, expected_response):

### Create a `SessionLocal` class

Each instance of the `SessionLocal` class will be a database session. The class itself is not a database session yet.

But once we create an instance of the `SessionLocal` class, this instance will be the actual database session.

    from docs_src.sql_databases.sql_app_py39 import alt_main

    # Ensure import side effects are re-executed
    importlib.reload(alt_main)

    with TestClient(alt_main.app) as c:
        yield c
    if test_db.is_file():  # pragma: nocover
        test_db.unlink()
    os.chdir(cwd)


@needs_py39
# TODO: pv2 add version with Pydantic v2
@needs_pydanticv1

    from docs_src.sql_databases.sql_app_py310 import main

    # Ensure import side effects are re-executed
    importlib.reload(main)
    with TestClient(main.app) as c:
        yield c
    if test_db.is_file():  # pragma: nocover
        test_db.unlink()
    os.chdir(cwd)


@needs_py310
# TODO: pv2 add version with Pydantic v2
@needs_pydanticv1

    from docs_src.sql_databases.sql_app_py39 import main

    # Ensure import side effects are re-executed
    importlib.reload(main)
    with TestClient(main.app) as c:
        yield c
    if test_db.is_file():  # pragma: nocover
        test_db.unlink()
    os.chdir(cwd)


@needs_py39
# TODO: pv2 add version with Pydantic v2
@needs_pydanticv1

    ```

=== "Python 3.10+ non-Annotated"

    !!! tip
        Prefer to use the `Annotated` version if possible.

    ```Python hl_lines="7"
    {!> ../../../docs_src/dependencies/tutorial001_py310.py!}
    ```

=== "Python 3.8+ non-Annotated"

    !!! tip
        Prefer to use the `Annotated` version if possible.

    ```Python hl_lines="11"
    {!> ../../../docs_src/dependencies/tutorial001.py!}
    ```

    db_user = crud.get_user_by_email(db, email=user.email)
    if db_user:
        raise HTTPException(status_code=400, detail="Email already registered")
    return crud.create_user(db=db, user=user)


@app.get("/users/", response_model=list[schemas.User])
def read_users(skip: int = 0, limit: int = 100, db: Session = Depends(get_db)):
    users = crud.get_users(db, skip=skip, limit=limit)
    return users

def test_websocket_with_cookie():
    client = TestClient(app, cookies={"session": "fakesession"})
    with pytest.raises(WebSocketDisconnect):
        with client.websocket_connect("/items/foo/ws") as websocket:
            message = "Message one"
            websocket.send_text(message)
            data = websocket.receive_text()
            assert data == "Session cookie or query token value is: fakesession"