app = FastAPI()


class Item(BaseModel):
    name: str
    description: Union[str, None] = None
    price: float
    tax: Union[float, None] = None


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


@app.put("/items/{item_id}")
async def update_item(
    item_id: int, item: Item, user: User, importance: Annotated[int, Body()]
):

{!../../docs_src/security/tutorial005.py!}
```

## 校验 `username` 与数据形状

我们可以校验是否获取了 `username`，并抽取作用域。

然后，使用 Pydantic 模型校验数据（捕获 `ValidationError` 异常），如果读取 JWT 令牌或使用 Pydantic 模型验证数据时出错，就会触发之前创建的 `HTTPException` 异常。

对此，要使用新的属性 `scopes` 更新 Pydantic 模型 `TokenData`。

使用 Pydantic 验证数据可以确保数据中含有由作用域组成的**字符串列表**，以及 `username` 字符串等内容。

反之，如果使用**字典**或其它数据结构，就有可能在后面某些位置破坏应用，形成安全隐患。

    default String getLdapSecurityPrincipal(final String username) {
        final String value;
        final int maxLength = getLdapMaxUsernameLengthAsInteger();
        if (username == null) {
            value = StringUtil.EMPTY;
        } else if (maxLength >= 0 && username.length() > maxLength) {
            value = username.substring(0, maxLength);
        } else {
            value = username;
        }

    return item


@app.get("/items/", tags=["items"])
async def read_items():
    return [{"name": "Foo", "price": 42}]


@app.get("/users/", tags=["users"])
async def read_users():

                    AuthenticationContext authCtx = AuthenticationContext.forProxy(null, repo);
                    p.setUserName(authCtx.get(AuthenticationContext.USERNAME));
                    p.setPassword(authCtx.get(AuthenticationContext.PASSWORD));
                    p.setNtlmDomain(authCtx.get(AuthenticationContext.NTLM_DOMAIN));

            "X-Token": "fake-super-secret-token",
            "X-Key": "fake-super-secret-key",
        },
    )
    assert response.status_code == 200, response.text
    assert response.json() == [{"username": "Rick"}, {"username": "Morty"}]


@needs_py39
def test_openapi_schema(client: TestClient):
    response = client.get("/openapi.json")
    assert response.status_code == 200, response.text

	flag.StringVar(&minioUsername, "u", "", "MinIO Username")
	flag.StringVar(&minioPassword, "p", "", "MinIO Password")
	flag.BoolVar(&displayCreds, "d", false, "Only show generated credentials")
	flag.DurationVar(&expiryDuration, "e", 0, "Request a duration of validity for the generated credential")
	flag.StringVar(&bucketToList, "b", "", "Bucket to list (defaults to username)")

    private Date kickOffTime;
    private Date pwdLastChangeTime;
    private Date pwdCanChangeTime;
    private Date pwdMustChangeTime;
    private short logonCount;
    private short badPasswordCount;
    private String userName;
    private String userDisplayName;
    private String logonScript;
    private String profilePath;
    private String homeDirectory;
    private String homeDrive;
    private String serverName;

							</c:if>
							<c:choose>
								<c:when test="${!empty username && username != 'guest'}">
									<li class="nav-item">
										<div class="dropdown">
											<a class="nav-link dropdown-toggle" data-toggle="dropdown"
												href="#" role="button" aria-haspopup="true"
												aria-expanded="false"> <em class="fa fa-fw fa-user">${username}
											</a>

        //    <proxy>
        //      <active>true</active>
        //      <protocol>http</protocol>
        //      <host>proxy.somewhere.com</host>
        //      <port>8080</port>
        //      <username>proxyuser</username>
        //      <password>somepassword</password>
        //      <nonProxyHosts>www.google.com|*.somewhere.com</nonProxyHosts>
        //    </proxy>
        //  </proxies>