使用JOLT转换列表为对象数组并填充attr关联codes数据

算力阿峰

2026-8-12

JSON转换需求：用codes字段丰富items中的attr数组为对象映射

输入JSON

{"items": {"a1b2xxxx": {"name": "item 1","attr": ["A","B","C"]},"c2b2cxxxx": {"name": "item 2","attr": ["D","E","F"]}},"codes": {"A": {"color": "green"},"B": {"size": "M"},"C": {"sku": "NS"},"D": {"stock": 2},"E": {"some_key": "some_value"},"F": {"foo": "bar"}}}

期望输出JSON

{"items": {"a1b2xxxx": {"name": "item 1","attr": {"A": {"color": "green"},"B": {"size": "M"},"C": {"sku": "NS"}}},"c2b2xxxx": {"name": "item 2","attr": {"D": {"stock": 2},"E": {"some_key": "some_value"},"F": {"foo": "bar"}}}},"codes": {"A": {"color": "green"},"B": {"size": "M"},"C": {"sku": "NS"},"D": {"stock": 2},"E": {"some_key": "some_value"},"F": {"foo": "bar"}}}

当前尝试的转换器

[{"operation": "cardinality","spec": {"items": {"*": {"attr": "ONE"}}}}]

解决方案

你之前用cardinality操作的思路有误，cardinality: "ONE"是将数组转为单个元素（仅保留第一个），无法实现把数组所有元素映射为对象键值对的需求。正确做法是使用shift操作重组结构，同时引用codes中的对应值：

[
  {
    "operation": "shift",
    "spec": {
      "codes": "&",
      "items": {
        "*": {
          "name": "&1.name",
          "attr": {
            "*": {
              "@(3,codes,&)": "&2.attr.&"
            }
          }
        }
      }
    }
  }
]

转换逻辑说明

保留codes字段不变（"codes": "&"）；
遍历items下的所有子项（"*"），保留原name字段；
遍历每个子项的attr数组元素（"*"），通过@(3,codes,&)向上3层获取codes中与当前数组元素同名的对象，再将其映射到当前子项的attr对象下，以数组元素为键（"&2.attr.&"）。