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。

    return form_data


@app.get("/users/me")
def read_users_me(current_user: Optional[User] = Depends(get_current_user)):
    if current_user is None:
        return {"msg": "Create an account first"}
    return current_user


client = TestClient(app)


def test_security_oauth2():
    response = client.get("/users/me", headers={"Authorization": "Bearer footokenbar"})

    return form_data


@app.get("/users/me")
def read_users_me(current_user: Optional[User] = Depends(get_current_user)):
    if current_user is None:
        return {"msg": "Create an account first"}
    return current_user


client = TestClient(app)


def test_security_oauth2():
    response = client.get("/users/me", headers={"Authorization": "Bearer footokenbar"})

    return form_data


@app.get("/users/me")
# Here we use string annotations to test them
def read_current_user(current_user: "User" = Depends(get_current_user)):
    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

Und wenn Sie den Scope `me`, aber nicht den Scope `items` auswählen, können Sie auf `/users/me/` zugreifen, aber nicht auf `/users/me/items/`.

                },
            ]
        }
    )


def test_users_me_token_jessica(client: TestClient):
    response = client.get("/users/me?token=jessica")
    assert response.status_code == 200
    assert response.json() == {"username": "fakecurrentuser"}


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

            ]
        }
    )


@needs_py39
def test_users_me_token_jessica(client: TestClient):
    response = client.get("/users/me?token=jessica")
    assert response.status_code == 200
    assert response.json() == {"username": "fakecurrentuser"}


@needs_py39
def test_users_me_with_no_token(client: TestClient):
    response = client.get("/users/me")
    assert response.status_code == 422

package gradlebuild.binarycompatibility;

import japicmp.filter.Filter;
import me.champeau.gradle.japicmp.JApiCmpWorkAction;
import me.champeau.gradle.japicmp.JApiCmpWorkerAction;
import me.champeau.gradle.japicmp.JapiCmpWorkerConfiguration;
import me.champeau.gradle.japicmp.filters.FilterConfiguration;
import me.champeau.gradle.japicmp.report.RichReport;
import me.champeau.gradle.japicmp.report.RuleConfiguration;
import org.gradle.api.Action;

If you don't select any scope, you will be "authenticated", but when you try to access `/users/me/` or `/users/me/items/` you will get an error saying that you don't have enough permissions. You will still be able to access `/status/`.

And if you select the scope `me` but not the scope `items`, you will be able to access `/users/me/` but not `/users/me/items/`.

      fail("no exception thrown");
    } catch (IllegalArgumentException expected) {
    }
  }

  public void testCheckArgument_simpleMessage_success() {
    Preconditions.checkArgument(true, IGNORE_ME);
  }

  public void testCheckArgument_simpleMessage_failure() {
    try {
      Preconditions.checkArgument(false, new Message());
      fail("no exception thrown");
    } catch (IllegalArgumentException expected) {