如何根据过滤后的键生成documentItemToSigner数组？

需求 #

给定过滤后的数组，每个元素包含contentVersion、documentName及最多3组documentItemName{n}、typeCd{n}、subtypeCd{n}字段（n为1/2/3）。需根据每个contentVersion下存在的documentItemName{n}数量，生成对应数量的documentItemToSigner对象数组，每个对象映射对应字段并添加eSignLiveExtension属性（extractInd根据subtypeCd取值，示例中CAPTURE对应true，LABEL对应false）。

原始Payload #

[
      {
        "contentVersion": "068DQ000000lK0iYAE",
        "documentName": "ESRA with Exhibit_A",
        "documentItemName1": "Signature001",
        "typeCd1": "Signature",
        "typeCd2": null,
        "typeCd3": null,
        "subtypeCd1": "CAPTURE",
        "subtypeCd2": null,
        "subtypeCd3": null
      },
      {
        "contentVersion": "068DQ000000kK0OYAU",
        "documentName": "Agreement 1",
        "documentItemName1": "Signature001",
        "documentItemName2": "Signature002",
        "typeCd1": "Signature",
        "typeCd2": "Signature",
        "typeCd3": null,
        "subtypeCd1": "CAPTURE",
        "subtypeCd2": "LABEL",
        "subtypeCd3": null
      },
      {
        "contentVersion": "068DQ000000lK0OYAU",
        "documentName": "Agreement 2",
        "documentItemName1": "Signature001",
        "documentItemName2": "Signature002",
        "documentItemName3": "Signature003",
        "typeCd1": "Signature",
        "typeCd2": "Signature",
        "typeCd3": "Signature",
        "subtypeCd1": "CAPTURE",
        "subtypeCd2": "CAPTURE",
        "subtypeCd3": "CAPTURE"
      }
    ]

用户尝试的脚本 #

"documentItemToSigner": (payload filter ((g, index) -> g.contentVersion == "068DQ000000lK0OYAU")) map ((item, index) -> {
    "typeCd": item."typeCd{n}",
    "subtypeCd": item."subtypeCd{n}",
    "eSignLiveExtension": {
      "extractInd": true
    },
    "documentItemName": item."documentItemName{n}"
  })

期望输出 #

{
  "documentItemToSigner": [
    {
      "typeCd": "Signature",
      "subtypeCd": "CAPTURE",
      "eSignLiveExtension": {
        "extractInd": true
      },
      "documentItemName": "Signature001"
    },
    {
      "typeCd": "Signature",
      "subtypeCd": "LABEL",
      "documentItemName": "Signature002",
      "eSignLiveExtension": {
        "extractInd": false
      }
    },
    {
      "typeCd": "Signature",
      "subtypeCd": "CAPTURE",
      "eSignLiveExtension": {
        "extractInd": true
      },
      "documentItemName": "Signature003"
    }
  ]
}

解决方案 #

使用DataWeave脚本实现，核心逻辑是遍历1-3的序号，检查对应documentItemName{n}是否存在，存在则生成对应对象：

%dw 2.0
output application/json
var targetContentVersion = "068DQ000000lK0OYAU"
---
{
  documentItemToSigner: (payload filter ($.contentVersion == targetContentVersion)) flatMap ((item) -> 
    (1 to 3) filter (n -> item["documentItemName$(n)"] != null) map ((n) -> {
      typeCd: item["typeCd$(n)"],
      subtypeCd: item["subtypeCd$(n)"],
      documentItemName: item["documentItemName$(n)"],
      eSignLiveExtension: {
        extractInd: item["subtypeCd$(n)"] == "CAPTURE"
      }
    })
  )
}

关键说明 #

1. 过滤目标条目：用filter筛选出指定contentVersion的元素
2. 遍历序号并检查有效性：通过(1 to 3)遍历3个序号，用filter排除documentItemName{n}为null的条目
3. 动态获取字段值：用item["fieldName$(n)"]的语法动态拼接字段名，获取对应序号的字段值
4. 设置extractInd：根据subtypeCd的值判断，CAPTURE对应true，其他情况（如示例中的LABEL）对应false

内容的提问来源于stack exchange，提问作者veejay