如何提取yq脚本通用逻辑，实现DRY原则？

我有一段用于合并去重KubeConfig文件中clusters和contexts的yq脚本，目前针对两个字段的处理逻辑完全重复，想提取通用代码块，让脚本符合DRY（Don't Repeat Yourself）原则。

原yq脚本 #

yq eval-all '
    .clusters = ( 
        (   
            (.clusters[] | {.name: .}) as $item ireduce ({}; . * $item)
        ) as $uniqueMap |
        ( $uniqueMap  | to_entries | .[]) as $item ireduce([]; . + $item.value)
    ) | 
    .contexts = ( 
        (
            (.contexts[] | {.name: .}) as $item ireduce ({}; . * $item)
        ) as $uniqueMap |
        ( $uniqueMap  | to_entries | .[]) as $item ireduce([]; . + $item.value)
    ) | 
    select(fi == 0)' konfig monfig

待提取的通用代码块 #

其中«KEY»代表可替换的目标字段名（如clusters/contexts）：

.<<KEY>> = (
        (
            (.<<KEY>>[] | {.name: .}) as $item ireduce ({}; . * $item)
        ) as $uniqueMap |
        ( $uniqueMap  | to_entries | .[]) as $item ireduce([]; . + $item.value)
    )

输入文件 #

konfig文件 #

# konfig
apiVersion: apiVersion-keep
clusters:
- cluster:
    certificate-authority-data: cad-0
    server: server-0
  name: name-0
- cluster:
    certificate-authority-data: cad-1-discard
    server: server-1-discard
  name: name-1
- cluster:
    certificate-authority-data: cad-2
    server: server-2
  name: name-2
contexts:
- context:
    cluster: cluster-0
    user: user-0
  name: name-0
- context:
    cluster: cluster-1-discard
    user: user-1-discard
  name: name-1
- context:
    cluster: cluster-2
    user: user-2
  name: name-2
current-context: name-keep

monfig文件 #

# monfig
apiVersion: apiVersion-discard
clusters:
- cluster:
    certificate-authority-data: cad-1-keep
    server: server-1-keep
  name: name-1
contexts:
- context:
    cluster: cluster-1-keep
    user: user-1-keep
  name: name-1
current-context: name-discard

预期输出 #

apiVersion: apiVersion-keep
clusters:
- cluster:
    certificate-authority-data: cad-0
    server: server-0
  name: name-0
- cluster:
    certificate-authority-data: cad-1-keep
    server: server-1-keep
  name: name-1
- cluster:
    certificate-authority-data: cad-2
    server: server-2
  name: name-2
contexts:
- context:
    cluster: cluster-0
    user: user-0
  name: name-0
- context:
    cluster: cluster-1-keep
    user: user-1-keep
  name: name-1
- context:
    cluster: cluster-2
    user: user-2
  name: name-2
current-context: name-keep

重构后的DRY风格脚本 #

利用yq的def关键字定义通用去重函数，实现逻辑复用：

yq eval-all '
    def deduplicate(key):
        .[key] = (
            (.[key][] | {.name: .}) as $item ireduce ({}; . * $item)
            | to_entries | .[] | .value
        );
    deduplicate("clusters") | deduplicate("contexts") | select(fi == 0)
' konfig monfig

脚本说明 #

1. 定义通用函数deduplicate(key)：接收字段名参数key，内部完成「数组转映射去重→转回数组」的逻辑，后出现的同名字段会覆盖先出现的。
2. 复用函数处理目标字段：分别传入"clusters"和"contexts"，完成两个字段的去重合并。
3. 保留基准文件的其他字段：通过select(fi == 0)确保最终输出保留第一个输入文件（konfig）中的非目标字段（如apiVersion、current-context）。

内容的提问来源于stack exchange，提问作者Noel Yap