## 用 `PATCH` 进行部分更新

<a href="https://developer.mozilla.org/zh-CN/docs/Web/HTTP/Methods/PATCH" class="external-link" target="_blank">HTTP `PATCH`</a> 操作用于更新 *部分* 数据。

即，只发送要更新的数据，其余数据保持不变。

/// note | 笔记

`PATCH` 没有 `PUT` 知名，也怎么不常用。

很多人甚至只用 `PUT` 实现部分更新。

**FastAPI** 对此没有任何限制，可以**随意**互换使用这两种操作。

但本指南也会分别介绍这两种操作各自的用途。

///

### 使用 Pydantic 的 `exclude_unset` 参数

Вы также можете объявить параметры тела запроса как необязательные, установив значение по умолчанию, равное `None`:

{* ../../docs_src/body_multiple_params/tutorial001_an_py310.py hl[18:20] *}

/// note | Заметка

Заметьте, что в данном случае параметр `item`, который будет взят из тела запроса, необязателен. Так как было установлено значение `None` по умолчанию.

///

Это означает, что можно передавать только те данные, которые необходимо обновить, оставляя остальные нетронутыми.

/// note | Технические детали

`PATCH` менее распространен и известен, чем `PUT`.

А многие команды используют только `PUT`, даже для частичного обновления.

## 声明 `Cookie` 参数

声明 `Cookie` 参数的方式与声明 `Query` 和 `Path` 参数相同。

第一个值是默认值，还可以传递所有验证参数或注释参数：


{* ../../docs_src/cookie_params/tutorial001_an_py310.py hl[9] *}

/// note | 技术细节

`Cookie` 、`Path` 、`Query` 是**兄弟类**，都继承自共用的 `Param` 类。

注意，从 `fastapi` 导入的 `Query`、`Path`、`Cookie` 等对象，实际上是返回特殊类的函数。

///

/// info | 说明

必须使用 `Cookie` 声明 cookie 参数，否则该参数会被解释为查询参数。

///

import org.eclipse.aether.artifact.Artifact;
import org.eclipse.aether.resolution.ArtifactDescriptorException;
import org.eclipse.aether.resolution.ArtifactDescriptorResult;

/**
 * Maven relocation source.
 * Note: implementations of this component should avoid the "default" name (has special meaning in Eclipse Sisu) and
 * explicitly order implementations using Sisu priorities.
 *
 * @since 4.0.0

# Rules for building and testing new FIPS snapshots.
# For example:
#
#	make v1.2.3.zip
#	make v1.2.3.test
#
# and then if changes are needed, check them into master
# and run 'make v1.2.3.rm' and repeat.
#
# Note that once published a snapshot zip file should never
# be modified. We record the sha256 hashes of the zip files
# in fips140.sum, and the cmd/go/internal/fips140 test checks
# that the zips match.
#

    assertThat(Quantiles.scale(10).index(5).computeInPlace(78.9, 12.3, 45.6))
        .isWithin(ALLOWED_ERROR)
        .of(45.6);
  }

  public void testScale_indexes_varargs_compute_doubleCollection() {
    // Note that we specify index 1 twice, which by the method contract should be ignored.
    assertThat(Quantiles.scale(10).indexes(0, 10, 5, 1, 8, 1).compute(SIXTEEN_SQUARES_DOUBLES))
        .comparingValuesUsing(QUANTILE_CORRESPONDENCE)

    assertThat(Quantiles.scale(10).index(5).computeInPlace(78.9, 12.3, 45.6))
        .isWithin(ALLOWED_ERROR)
        .of(45.6);
  }

  public void testScale_indexes_varargs_compute_doubleCollection() {
    // Note that we specify index 1 twice, which by the method contract should be ignored.
    assertThat(Quantiles.scale(10).indexes(0, 10, 5, 1, 8, 1).compute(SIXTEEN_SQUARES_DOUBLES))
        .comparingValuesUsing(QUANTILE_CORRESPONDENCE)

The query parameter `q` is of type `str | None`, that means that it's of type `str` but could also be `None`, and indeed, the default value is `None`, so FastAPI will know it's not required.

/// note

FastAPI will know that the value of `q` is not required because of the default value `= None`.

Having `str | None` will allow your editor to give you better support and detect errors.

///

```

#### Etcd

MinIO supports storing encrypted IAM assets in etcd, if KMS is configured. Please refer to how to encrypt your config and IAM credentials [here](https://github.com/minio/minio/blob/master/docs/kms/IAM.md).