You can connect with <a href="https://tiangolo.com" class="external-link" target="_blank">me (Sebastián Ramírez / `tiangolo`)</a>, the author.

You can:

* <a href="https://github.com/tiangolo" class="external-link" target="_blank">Follow me on **GitHub**</a>.
    * See other Open Source projects I have created that could help you.
    * Follow me to see when I create a new Open Source project.

@app.get("/users/me")
def read_current_user(credentials: Optional[HTTPBasicCredentials] = Security(security)):
    if credentials is None:
        return {"msg": "Create an account first"}
    return {"username": credentials.username, "password": credentials.password}


client = TestClient(app)


def test_security_http_basic():
    response = client.get("/users/me", auth=("john", "secret"))

Si no seleccionas ningún scope, estarás "autenticado", pero cuando intentes acceder a `/users/me/` o `/users/me/items/` obtendrás un error diciendo que no tienes suficientes permisos. Aún podrás acceder a `/status/`.

Y si seleccionas el scope `me` pero no el scope `items`, podrás acceder a `/users/me/` pero no a `/users/me/items/`.

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


def test_token(mod: ModuleType):
    client = TestClient(mod.app)
    access_token = get_access_token(client=client)
    response = client.get(
        "/users/me", headers={"Authorization": f"Bearer {access_token}"}

security = HTTPBasic(realm="simple", description="HTTPBasic scheme")


@app.get("/users/me")
def read_current_user(credentials: HTTPBasicCredentials = Security(security)):
    return {"username": credentials.username, "password": credentials.password}


client = TestClient(app)


def test_security_http_basic():
    response = client.get("/users/me", auth=("john", "secret"))
    assert response.status_code == 200, response.text

它们会为每个*路径操作*进行单独检查。

## 查看文档

打开 API 文档，进行身份验证，并指定要授权的作用域。

<img src="/img/tutorial/security/image11.png">

没有选择任何作用域，也可以进行**身份验证**，但访问 `/uses/me` 或 `/users/me/items` 时，会显示没有足够的权限。但仍可以访问 `/status/`。

如果选择了作用域 `me`，但没有选择作用域 `items`，则可以访问 `/users/me/`，但不能访问 `/users/me/items`。

这就是通过用户提供的令牌使用第三方应用访问这些*路径操作*时会发生的情况，具体怎样取决于用户授予第三方应用的权限。

## 关于第三方集成

本例使用 OAuth2 **密码**流。

这种方式适用于登录我们自己的应用，最好使用我们自己的前端。

def test_security_http_basic(client: TestClient):
    response = client.get("/users/me", auth=("stanleyjobson", "swordfish"))
    assert response.status_code == 200, response.text
    assert response.json() == {"username": "stanleyjobson"}


def test_security_http_basic_no_credentials(client: TestClient):
    response = client.get("/users/me")
    assert response.json() == {"detail": "Not authenticated"}

client = TestClient(app)


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


def test_security_http_digest_no_credentials():
    response = client.get("/users/me")
    assert response.status_code == 200, response.text

app = FastAPI()

security = HTTPBearer()


@app.get("/users/me")
def read_current_user(credentials: HTTPAuthorizationCredentials = Security(security)):
    return {"scheme": credentials.scheme, "credentials": credentials.credentials}


client = TestClient(app)


def test_security_http_bearer():
    response = client.get("/users/me", headers={"Authorization": "Bearer foobar"})

security = HTTPBearer(description="HTTP Bearer token scheme")


@app.get("/users/me")
def read_current_user(credentials: HTTPAuthorizationCredentials = Security(security)):
    return {"scheme": credentials.scheme, "credentials": credentials.credentials}


client = TestClient(app)


def test_security_http_bearer():
    response = client.get("/users/me", headers={"Authorization": "Bearer foobar"})