@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


@app.get("/users/{user_id}", response_model=schemas.User)
def read_user(user_id: int, db: Session = Depends(get_db)):
    db_user = crud.get_user(db, user_id=user_id)
    if db_user is None:

    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()
    # Import while creating the client to create the DB after starting the test session
    from docs_src.sql_databases.sql_app_py39.tests import test_sql_app

    # Ensure import side effects are re-executed

    finally:
        db.close()


app.dependency_overrides[get_db] = override_get_db

client = TestClient(app)


def test_create_user():
    response = client.post(
        "/users/",
        json={"email": "******@****.***", "password": "chimichangas4life"},
    )
    assert response.status_code == 200, response.text
    data = response.json()
    assert data["email"] == "******@****.***"

    fake_hashed_password = user.password + "notreallyhashed"
    db_user = models.User(email=user.email, hashed_password=fake_hashed_password)
    db_user.save()
    return db_user


def get_items(skip: int = 0, limit: int = 100):
    return list(models.Item.select().offset(skip).limit(limit))


def create_user_item(item: schemas.ItemCreate, user_id: int):
    db_item = models.Item(**item.dict(), owner_id=user_id)
    db_item.save()

一般是在 `main.py` 中调用这行代码，但在 `main.py` 里，这行代码用于创建 `sql_app.db`，但是现在要为测试创建 `test.db`。

因此，要在测试代码中添加这行代码创建新的数据库文件。

```Python hl_lines="16"
{!../../../docs_src/sql_databases/sql_app/tests/test_sql_app.py!}
```

## 覆盖依赖项

接下来，创建覆盖依赖项，并为应用添加覆盖内容。

```Python hl_lines="19-24  27"
{!../../../docs_src/sql_databases/sql_app/tests/test_sql_app.py!}
```

!!! tip "提示"

def get_password_hash(password):
    return pwd_context.hash(password)


def get_user(db, username: str):
    if username in db:
        user_dict = db[username]
        return UserInDB(**user_dict)


def authenticate_user(fake_db, username: str, password: str):
    user = get_user(fake_db, username)
    if not user:
        return False
    if not verify_password(password, user.hashed_password):

    if item_id not in fake_db:
        raise HTTPException(status_code=404, detail="Item not found")
    return fake_db[item_id]


@app.post("/items/", response_model=Item)
async def create_item(item: Item, x_token: str = Header()):
    if x_token != fake_secret_token:
        raise HTTPException(status_code=400, detail="Invalid X-Token header")
    if item.id in fake_db:

    if item_id not in fake_db:
        raise HTTPException(status_code=404, detail="Item not found")
    return fake_db[item_id]


@app.post("/items/", response_model=Item)
async def create_item(item: Item, x_token: Annotated[str, Header()]):
    if x_token != fake_secret_token:
        raise HTTPException(status_code=400, detail="Invalid X-Token header")
    if item.id in fake_db:

```Python
# db._state = PeeweeConnectionState()
```

& 📁 `sql_app/main.py` 📁, 🏤 💪 `async` 🔗 `reset_db_state()` & ❎ ⚫️ ⏮️ `pass`:

```Python
async def reset_db_state():
#     database.db._state._state.set(db_state_default.copy())
#     database.db._state.reset()
    pass
```

⤴️ 🏃 👆 📱 ⏮️ Uvicorn:

<div class="termy">

from sqlalchemy import create_engine
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker

SQLALCHEMY_DATABASE_URL = "sqlite:///./sql_app.db"
# SQLALCHEMY_DATABASE_URL = "postgresql://user:password@postgresserver/db"

engine = create_engine(
    SQLALCHEMY_DATABASE_URL, connect_args={"check_same_thread": False}
)
SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)