"msg": "String should match pattern '^password$'",
                "input": grant_type,
                "ctx": {"pattern": "^password$"},
            }
        ]
    }


def test_strict_login_correct_grant_type():
    response = client.post(
        "/login",
        data={"username": "johndoe", "password": "secret", "grant_type": "password"},
    )
    assert response.status_code == 200

                "msg": "String should match pattern '^password$'",
                "input": grant_type,
                "ctx": {"pattern": "^password$"},
            }
        ]
    }


def test_strict_login_correct_correct_grant_type():
    response = client.post(
        "/login",
        data={"username": "johndoe", "password": "secret", "grant_type": "password"},
    )

* The **input model** needs to be able to have a password.
* The **output model** should not have a password.
* The **database model** would probably need to have a hashed password.

/// danger

Never store user's plaintext passwords. Always store a "secure hash" that you can then verify.

If you don't know, you will learn what a "password hash" is in the [security chapters](security/simple-oauth2.md#password-hashing){.internal-link target=_blank}.

///

def get_mod(request: pytest.FixtureRequest):
    mod = importlib.import_module(f"docs_src.security.{request.param}")

    return mod


def get_access_token(*, username="johndoe", password="secret", client: TestClient):
    data = {"username": username, "password": password}
    response = client.post("/token", data=data)
    content = response.json()
    access_token = content.get("access_token")
    return access_token

Nunca deberías guardar passwords en texto plano, así que, usaremos el sistema de hash de passwords (falso).

Si los passwords no coinciden, devolvemos el mismo error.

#### Hashing de passwords { #password-hashing }

"Hacer hash" significa: convertir algún contenido (un password en este caso) en una secuencia de bytes (solo un string) que parece un galimatías.

    response = client.post("/login/", data={"username": "Foo", "password": "secret"})
    assert response.status_code == 200
    assert response.json() == {"username": "Foo", "password": "secret"}


def test_post_body_extra_form(client: TestClient):
    response = client.post(
        "/login/", data={"username": "Foo", "password": "secret", "extra": "extra"}
    )
    assert response.status_code == 422

///

## Password hashing { #password-hashing }

"Hashing" means converting some content (a password in this case) into a sequence of bytes (just a string) that looks like gibberish.

Whenever you pass exactly the same content (exactly the same password) you get exactly the same gibberish.

But you cannot convert from the gibberish back to the password.

### Why use password hashing { #why-use-password-hashing }

    if not user_dict:
        raise HTTPException(status_code=400, detail="Incorrect username or password")
    user = UserInDB(**user_dict)
    hashed_password = fake_hash_password(form_data.password)
    if not hashed_password == user.hashed_password:
        raise HTTPException(status_code=400, detail="Incorrect username or password")

    return {"access_token": user.username, "token_type": "bearer"}


@app.get("/users/me")

```Python
UserInDB(
    username="john",
    password="secret",
    email="******@****.***",
    full_name=None,
)
```

O más exactamente, usando `user_dict` directamente, con cualquier contenido que pueda tener en el futuro:

```Python
UserInDB(
    username = user_dict["username"],
    password = user_dict["password"],
    email = user_dict["email"],
    full_name = user_dict["full_name"],

                "msg": "String should match pattern '^password$'",
                "input": grant_type,
                "ctx": {"pattern": "^password$"},
            }
        ]
    }


def test_strict_login_correct_data():
    response = client.post(
        "/login",
        data={"username": "johndoe", "password": "secret", "grant_type": "password"},
    )
    assert response.status_code == 200