app = FastAPI()

oauth2_scheme = OAuth2PasswordBearer(tokenUrl="token")


class User(BaseModel):
    username: str
    email: Union[str, None] = None
    full_name: Union[str, None] = None
    disabled: Union[bool, None] = None


def fake_decode_token(token):
    return User(
        username=token + "fakedecoded", email="******@****.***", full_name="John Doe"
    )

from fastapi.testclient import TestClient
from pydantic import BaseModel

app = FastAPI()

api_key = APIKeyCookie(name="key")


class User(BaseModel):
    username: str


def get_current_user(oauth_header: str = Security(api_key)):
    user = User(username=oauth_header)
    return user


@app.get("/users/me")
def read_current_user(current_user: User = Depends(get_current_user)):
    return current_user

from pydantic import BaseModel

app = FastAPI()

api_key = APIKeyCookie(name="key", description="An API Cookie Key")


class User(BaseModel):
    username: str


def get_current_user(oauth_header: str = Security(api_key)):
    user = User(username=oauth_header)
    return user


@app.get("/users/me")
def read_current_user(current_user: User = Depends(get_current_user)):
    return current_user

Então, vamos rever de um ponto de vista simplificado:

* O usuário digita o `username` e a `senha` no frontend e aperta `Enter`.
* O frontend (rodando no browser do usuário) manda o `username` e a `senha` para uma URL específica na sua API (declarada com `tokenUrl="token"`).
* A API checa aquele `username` e `senha`, e responde com um "token" (nós não implementamos nada disso ainda).

    return client


def test_users_token_jessica(client: TestClient):
    response = client.get("/users?token=jessica")
    assert response.status_code == 200
    assert response.json() == [{"username": "Rick"}, {"username": "Morty"}]


def test_users_with_no_token(client: TestClient):
    response = client.get("/users")
    assert response.status_code == 422
    assert response.json() == IsDict(
        {

        title=app.title + " - ReDoc",
        redoc_js_url="https://unpkg.com/redoc@next/bundles/redoc.standalone.js",
    )


@app.get("/users/{username}")
async def read_user(username: str):

	g := errgroup.WithNErrs(len(users))

	for index := range users {
		index := index
		g.Go(func() error {
			userName := path.Dir(users[index])
			user, err := iamOS.loadUserIdentity(ctx, userName, userType)
			if err != nil && !errors.Is(err, errNoSuchUser) {
				return fmt.Errorf("unable to load the user `%s`: %w", userName, err)
			}
			userIdentities[index] = user
			return nil
		}, index)
	}

  /**
   * The decoded username, or an empty string if none is present.
   *
   * | URL                              | `username()` |
   * | :------------------------------- | :----------- |
   * | `http://host/`                   | `""`         |
   * | `http://username@host/`          | `"username"` |
   * | `http://username:password@host/` | `"username"` |
   * | `http://a%20b:c%20d@host/`       | `"a b"`      |

                                    <label for="username" class="col-sm-3 text-sm-right col-form-label"><la:message
                                            key="labels.webauth_username"/></label>
                                    <div class="col-sm-9">
                                        <la:errors property="username"/>
                                        <la:text styleId="username" property="username" styleClass="form-control"/>

	if n.ClientCert != "" && n.ClientKey == "" || n.ClientCert == "" && n.ClientKey != "" {
		return errors.New("cert and key must be specified as a pair")
	}

	if n.Username != "" && n.Password == "" || n.Username == "" && n.Password != "" {
		return errors.New("username and password must be specified as a pair")
	}

	if n.Streaming.Enable {
		if n.Streaming.ClusterID == "" {
			return errors.New("empty cluster id")
		}
	}