求助：含双层嵌套数组的复杂JSON的Jolt扁平化转换

问题需求 #

需要将包含key数组（含date字段）和value数组（嵌套values与orders两层数组）的输入JSON，扁平化为包含date、location、total_capacity、capacity_flag、order_type、consumed_capacity字段的对象数组，现有Jolt Spec无法正确获取date字段。

输入JSON #

{
  "key": [
    {
      "date": "27/09/2023"
    }
  ],
  "value": [
    {
      "values": [
        {
          "location": "3005",
          "total_capacity": 24,
          "capacity_flag": "",
          "orders": [
            {
              "order_type": "INIT",
              "consumed_capacity": 0
            },
            {
              "order_type": "PUSH",
              "consumed_capacity": 0
            }
          ]
        },
        {
          "location": "3007",
          "total_capacity": 72,
          "capacity_flag": "",
          "orders": [
            {
              "order_type": "INIT",
              "consumed_capacity": 0
            },
            {
              "order_type": "PUSH",
              "consumed_capacity": 0
            },
            {
              "order_type": "RPLN",
              "consumed_capacity": 0
            }
          ]
        }
      ]
    }
  ]
}

期望输出JSON #

[
  {
    "date": "27/09/2023",
    "location": "3005",
    "total_capacity": 24,
    "capacity_flag": "",
    "order_type": "INIT",
    "consumed_capacity": 0
  },
  {
    "date": "27/09/2023",
    "location": "3005",
    "total_capacity": 24,
    "capacity_flag": "",
    "order_type": "PUSH",
    "consumed_capacity": 0
  },
  {
    "date": "27/09/2023",
    "location": "3007",
    "total_capacity": 72,
    "capacity_flag": "",
    "order_type": "INIT",
    "consumed_capacity": 0
  },
  {
    "date": "27/09/2023",
    "location": "3007",
    "total_capacity": 72,
    "capacity_flag": "",
    "order_type": "PUSH",
    "consumed_capacity": 0
  },
  {
    "date": "27/09/2023",
    "location": "3007",
    "total_capacity": 72,
    "capacity_flag": "",
    "order_type": "RPLN",
    "consumed_capacity": 0
  }
]

尝试的Jolt Spec（date字段无法正确获取） #

[
  {
    "operation": "shift",
    "spec": {
      "value": {
        "*": {
          "values": {
            "*": {
              "orders": {
                "*": {
                  "order_type": "&3.&1.order_type",
                  "consumed_capacity": "&3.&1.consumed_capacity",
                  "@2,location": "&3.&1.location",
                  "@2,total_capacity": "&3.&1.total_capacity",
                  "@2,capacity_flag": "&3.&1.capacity_flag"
                }
              }
            }
          }
        }
      }
    }
  },
  { // 移除上一步生成的中间对象键
    "operation": "shift",
    "spec": {
      "*": {
        "*": ""
      }
    }
  }
]

正确的Jolt Spec #

[
  {
    "operation": "shift",
    "spec": {
      "value": {
        "*": {
          "values": {
            "*": {
              "orders": {
                "*": {
                  "order_type": "&3.&1.order_type",
                  "consumed_capacity": "&3.&1.consumed_capacity",
                  "@2,location": "&3.&1.location",
                  "@2,total_capacity": "&3.&1.total_capacity",
                  "@2,capacity_flag": "&3.&1.capacity_flag",
                  "@(5,key[0].date)": "&3.&1.date"
                }
              }
            }
          }
        }
      }
    }
  },
  {
    "operation": "shift",
    "spec": {
      "*": {
        "*": ""
      }
    }
  }
]

关键说明 #

• 在第一个shift操作中，通过@(5,key[0].date)引用最外层key数组中的date字段：5表示从当前orders子元素位置向上回溯5层层级（依次到orders、当前values元素、values数组、value数组元素、根节点），从而正确跨层级获取date值。
• 第二个shift操作保持原有逻辑，用于移除中间生成的层级键，将结构扁平化为最终的对象数组。

内容的提问来源于stack exchange，提问作者Thiyagaraj Narayanan