# Einfaches OAuth2 mit Password und Bearer

Lassen Sie uns nun auf dem vorherigen Kapitel aufbauen und die fehlenden Teile hinzufügen, um einen vollständigen Sicherheits-Flow zu erhalten.

## `username` und `password` entgegennehmen

Wir werden **FastAPIs** Sicherheits-Werkzeuge verwenden, um den `username` und das `password` entgegenzunehmen.

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


@needs_pydanticv2
def test_post_body_extra_form(client: TestClient):
    response = client.post(
        "/login/", data={"username": "Foo", "password": "secret", "extra": "extra"}
    )
    assert response.status_code == 422

class OAuth2PasswordRequestForm:
    """
    This is a dependency class to collect the `username` and `password` as form data
    for an OAuth2 password flow.

    The OAuth2 specification dictates that for a password flow the data should be
    collected using form data (instead of JSON) and that it should have the specific
    fields `username` and `password`.

    All the initialization parameters are extracted from the request.

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


@needs_pydanticv1
def test_post_body_extra_form(client: TestClient):
    response = client.post(
        "/login/", data={"username": "Foo", "password": "secret", "extra": "extra"}
    )
    assert response.status_code == 422

            server = server.clone();

            String password = server.getPassword();
            if (securityDispatcher.isAnyEncryptedString(password)) {
                try {
                    if (securityDispatcher.isLegacyEncryptedString(password)) {
                        problems.add(new DefaultSettingsProblem(
                                "Legacy/insecurely encrypted password detected for server " + server.getId(),

    assert response.status_code == 200
    assert response.json() == {"username": "Foo", "password": "secret"}


# TODO: remove when deprecating Pydantic v1
@needs_pydanticv1
@needs_py39
def test_post_body_extra_form(client: TestClient):
    response = client.post(
        "/login/", data={"username": "Foo", "password": "secret", "extra": "extra"}
    )

# Simple OAuth2 with Password and Bearer

Now let's build from the previous chapter and add the missing parts to have a complete security flow.

## Get the `username` and `password`

We are going to use **FastAPI** security utilities to get the `username` and `password`.

OAuth2 specifies that when using the "password flow" (that we are using) the client/user must send a `username` and `password` fields as form data.

     */
    public String getPassword() {
        return password;
    }

    /**
     * Set the user's password which is used when connecting to the repository.
     *
     * @param password password of the user
     */
    public void setPassword(String password) {
        this.password = password;
    }

    /**
     * Get the username used to access the repository.
     *

                    "properties": {
                        "username": {"type": "string", "title": "Username"},
                        "password": {"type": "string", "title": "Password"},
                    },
                    "type": "object",
                    "required": ["username", "password"],
                    "title": "FormData",
                },
                "ValidationError": {

If it doesn't receive it, it returns an HTTP 401 "Unauthorized" error.

And returns a header `WWW-Authenticate` with a value of `Basic`, and an optional `realm` parameter.

That tells the browser to show the integrated prompt for a username and password.

Then, when you type that username and password, the browser sends them in the header automatically.