/// info

The additional header `WWW-Authenticate` with value `Bearer` we are returning here is also part of the spec.

Any HTTP (error) status code 401 "UNAUTHORIZED" is supposed to also return a `WWW-Authenticate` header.

In the case of bearer tokens (our case), the value of that header should be `Bearer`.

You can actually skip that extra header and it would still work.

/// info | Información

El header adicional `WWW-Authenticate` con el valor `Bearer` que estamos devolviendo aquí también es parte de la especificación.

Cualquier código de estado HTTP (error) 401 "UNAUTHORIZED" se supone que también debe devolver un header `WWW-Authenticate`.

En el caso de tokens bearer (nuestro caso), el valor de ese header debe ser `Bearer`.

/// info | Info

Der zusätzliche Header `WWW-Authenticate` mit dem Wert `Bearer`, den wir hier zurückgeben, ist ebenfalls Teil der Spezifikation.

Jeder HTTP-(Fehler-)Statuscode 401 „UNAUTHORIZED“ soll auch einen `WWW-Authenticate`-Header zurückgeben.

Im Fall von Bearer-Tokens (in unserem Fall) sollte der Wert dieses Headers `Bearer` lauten.

Sie können diesen zusätzlichen Header tatsächlich weglassen und es würde trotzdem funktionieren.

    return current_user


client = TestClient(app)


def test_security_oauth2():
    response = client.get("/users/me", headers={"Authorization": "Bearer footokenbar"})
    assert response.status_code == 200, response.text
    assert response.json() == {"username": "Bearer footokenbar"}


def test_security_oauth2_password_other_header():
    response = client.get("/users/me", headers={"Authorization": "Other footokenbar"})

client = TestClient(app)


def test_security_http_bearer():
    response = client.get("/users/me", headers={"Authorization": "Bearer foobar"})
    assert response.status_code == 200, response.text
    assert response.json() == {"scheme": "Bearer", "credentials": "foobar"}


def test_security_http_bearer_no_credentials():
    response = client.get("/users/me")

    return current_user


client = TestClient(app)


def test_security_oauth2():
    response = client.get("/users/me", headers={"Authorization": "Bearer footokenbar"})
    assert response.status_code == 200, response.text
    assert response.json() == {"username": "Bearer footokenbar"}


def test_security_oauth2_password_other_header():
    response = client.get("/users/me", headers={"Authorization": "Other footokenbar"})

    * But it needs authentication for that specific endpoint.
    * So, to authenticate with our API, it sends a header `Authorization` with a value of `Bearer ` plus the token.
    * If the token contains `foobar`, the content of the `Authorization` header would be: `Bearer foobar`.

## **FastAPI**'s `OAuth2PasswordBearer` { #fastapis-oauth2passwordbearer }

    assert response.status_code == 401, response.text
    assert response.json() == {"detail": "Not authenticated"}
    assert response.headers["WWW-Authenticate"] == "Bearer"


def test_token(client: TestClient):
    response = client.get("/items", headers={"Authorization": "Bearer testtoken"})
    assert response.status_code == 200, response.text
    assert response.json() == {"token": "testtoken"}

 */
public class AccessTokenHelper {

    /**
     * Default constructor.
     */
    public AccessTokenHelper() {
        // nothing
    }

    /**
     * The bearer string.
     */
    protected static final String BEARER = "Bearer";

    /**
     * The random instance.
     */
    protected Random random = new SecureRandom();

    /**
     * Generate the access token.
     * @return The access token.

# Simples OAuth2 com senha e Bearer { #simple-oauth2-with-password-and-bearer }

Agora vamos construir a partir do capítulo anterior e adicionar as partes que faltam para ter um fluxo de segurança completo.

## Obtenha o `username` e a `password` { #get-the-username-and-password }

É utilizado o utils de segurança da **FastAPI** para obter o `username` e a `password`.