# 更多模型

书接上文，多个关联模型这种情况很常见。

特别是用户模型，因为：

* **输入模型**应该含密码
* **输出模型**不应含密码
* **数据库模型**需要加密的密码

/// danger | "危险"

千万不要存储用户的明文密码。始终存储可以进行验证的**安全哈希值**。

如果不了解这方面的知识，请参阅[安全性中的章节](security/simple-oauth2.md#password-hashing){.internal-link target=_blank}，了解什么是**密码哈希**。

///

## 多个模型

下面的代码展示了不同模型处理密码字段的方式，及使用位置的大致思路：

//// tab | Python 3.10+

```Python hl_lines="7  9  14  20  22  27-28  31-33  38-39"

For example, if you are squeezing performance, you can install and use <a href="https://github.com/ijl/orjson" class="external-link" target="_blank">`orjson`</a> and set the response to be `ORJSONResponse`.

Import the `Response` class (sub-class) you want to use and declare it in the *path operation decorator*.

For large responses, returning a `Response` directly is much faster than returning a dictionary.

	ANDW	$0x6006000060060, R27, R5                        // ERROR "cannot use REGTMP as source"
	STP	(R3, R4), 0x1234567(R27)                         // ERROR "REGTMP used in large offset store"
	LDP	0x1234567(R27), (R3, R4)                         // ERROR "REGTMP used in large offset load"
	STP	(R26, R27), 700(R2)                              // ERROR "cannot use REGTMP as source"

Python'un önceki sürümlerinde, threadlerı veya <a href="https://www.gevent.org/" class="external-link" target="_blank">Gevent</a> kullanıyor olabilirdin. Ancak kodu anlamak, hata ayıklamak ve düşünmek çok daha karmaşık olurdu.

NodeJS / Browser JavaScript'in önceki sürümlerinde, "callback" kullanırdınız. Bu da <a href="http://callbackhell.com/" class="external-link" target="_blank">callbacks cehennemine</a> yol açar.

## Coroutine'ler

				t.Log("ListObjectVersions, bucket:", testCase.bucketName, "prefix:",
					testCase.prefix, "marker:", testCase.marker, "delimiter:",
					testCase.delimiter, "maxkeys:", testCase.maxKeys)

				resultV, err = obj.ListObjectVersions(context.Background(), testCase.bucketName,
					testCase.prefix, testCase.marker, "", testCase.delimiter, testCase.maxKeys)
			} else {

			expectErr:   true,
		},
		{
			value:       DefaultRetention{Mode: RetGovernance, Days: &invalidDays},
			expectedErr: fmt.Errorf("Default retention period too large for 'Days' %d", invalidDays),
			expectErr:   true,
		},
	}
	for _, tt := range tests {
		d, err := xml.MarshalIndent(&tt.value, "", "\t")
		if err != nil {
			t.Fatal(err)
		}

		}
		var terr zipindex.ErrNeedMoreData
		if errors.As(err, &terr) {
			size = int(terr.FromEnd)
			if size <= 0 || size > 100<<20 {
				return nil, ObjectInfo{}, errors.New("zip directory too large")
			}
		} else {
			return nil, ObjectInfo{}, err
		}
	}
}

// headObjectInArchiveFileHandler - HEAD Object in an archive file

      format: !!python/name:pymdownx.superfences.fence_code_format
  pymdownx.tilde:

  # pymdownx blocks
  pymdownx.blocks.admonition:
    types:
    - note
    - attention
    - caution
    - danger
    - error
    - tip
    - hint
    - warning
    # Custom types
    - info
    - check
  pymdownx.blocks.details:
  pymdownx.blocks.tab:
    alternate_style: True

Download a file, print its headers, and print its response body as a string.

The `string()` method on response body is convenient and efficient for small documents. But if the response body is large (greater than 1 MiB), avoid `string()` because it will load the entire document into memory. In that case, prefer to process the body as a stream.

=== ":material-language-kotlin: Kotlin"
    ```kotlin

 *     return map.isEmpty();
 *   }
 * });
 * }</pre>
 *
 * <p>Even if your non-test code does not use finalization, you can use this class to test for
 * leaks, by ensuring that objects are no longer strongly referenced:
 *
 * <pre>{@code
 * // Helper function keeps victim stack-unreachable.
 * private WeakReference<Foo> fooWeakRef() {
 *   Foo x = ....;
 *   WeakReference<Foo> weakRef = new WeakReference<>(x);