如何用yq依据已有布尔键值生成新的role键值对

输入YAML数据 #

- hostname: rk089-s11
  compute: false
  control: true
  master: false
- hostname: rk090-s11
  compute: false
  control: true
  master: true

期望输出 #

- hostname: rk089-s11
  role: control
- hostname: rk090-s11
  role: control,master

尝试的错误命令 #

yq -r '.[] |
[
    {
    "hostname": .hostname,
    "role": (
        ( ( .compute == true ) | "compute," ) +
        ( ( .control == true ) | "control," ) +
        ( ( .master == true ) | "master," )
    )
    }
]'|sed 's/,$//'

错误输出 #

- hostname: rk089-s11
  role: compute,control,master
- hostname: rk090-s11
  role: compute,control,master

修正后的命令及说明 #

正确命令 #

yq -r '.[] | {
  hostname: .hostname,
  role: (
    (if .compute then "compute," else "" end) +
    (if .control then "control," else "" end) +
    (if .master then "master," else "" end)
  ) | sub(",$", "")
}'

修正说明 #

之前的命令错误在于：( .compute == true ) | "compute,"这种写法不会根据布尔值过滤内容——yq中布尔值通过管道传递到字符串时，无论真假都会返回该字符串，导致即使字段为false也会拼接角色名。

改用if...then...else...end条件判断后，只有当对应字段为true时才拼接带逗号的角色名，否则拼接空字符串。最后通过yq内置的sub(",$", "")直接移除末尾的多余逗号，无需再调用sed处理。

内容的提问来源于stack exchange，提问作者aqn