求Jolt Spec：计算列表中指定键对应重复值的总和

需求说明 #

遍历输入列表中的每个对象，针对其中的returnItemAdjustments数组，筛选出returnAdjustmentTypeId等于RET_SALES_TAX_ADJ的条目，将这些条目的amount字段求和，最终输出包含原对象returnId和求和结果returnTax的对象列表。

输入示例 #

[
  {
    "returnId": "10051",
    "returnItemAdjustments": [
      {
        "returnItemSeqId": "00001",
        "amount": 28.64,
        "returnAdjustmentTypeId": "RET_SALES_TAX_ADJ",
        "description": "Return Sales Tax",
        "createdDate": null,
        "returnId": "10051",
        "returnAdjustmentId": "10051",
        "comments": "Return Sales Tax",
        "shipGroupSeqId": null
      },
      {
        "returnItemSeqId": "00001",
        "amount": 58.64,
        "returnAdjustmentTypeId": "RET_SALES_TAX_ADJ",
        "description": "Return Sales Tax",
        "createdDate": null,
        "returnId": "10051",
        "returnAdjustmentId": "10051",
        "comments": "Return Sales Tax",
        "shipGroupSeqId": null
      }
    ]
  },
  {
    "returnId": "10051",
    "returnItemAdjustments": [
      {
        "returnItemSeqId": "00002",
        "amount": 38.64,
        "returnAdjustmentTypeId": "RET_SALES_TAX_ADJ",
        "description": "Return Sales Tax",
        "createdDate": null,
        "returnId": "10051",
        "returnAdjustmentId": "10051",
        "comments": "Return Sales Tax",
        "shipGroupSeqId": null
      }
    ]
  }
]

预期输出 #

[
  {
    "returnId": "10051",
    "returnTax": 87.28
  },
  {
    "returnId": "10051",
    "returnTax": 38.64
  }
]

Jolt转换Spec #

[
  // 提取每个return对象的returnId及符合条件的金额
  {
    "operation": "shift",
    "spec": {
      "*": {
        "returnId": "[&1].returnId",
        "returnItemAdjustments": {
          "*": {
            "returnAdjustmentTypeId": {
              "RET_SALES_TAX_ADJ": {
                "@(2,amount)": "[&4].taxAmounts[]"
              }
            }
          }
        }
      }
    }
  },
  // 对金额数组求和得到returnTax
  {
    "operation": "modify-overwrite-beta",
    "spec": {
      "*": {
        "returnTax": "=sum(@(1,taxAmounts))"
      }
    }
  },
  // 移除临时字段，整理最终结构
  {
    "operation": "shift",
    "spec": {
      "*": {
        "returnId": "[&1].returnId",
        "returnTax": "[&1].returnTax"
      }
    }
  }
]

转换步骤解释 #

• 第一步（Shift）：遍历输入列表的每个元素，保留returnId；同时筛选returnItemAdjustments中类型为RET_SALES_TAX_ADJ的条目，将对应amount存入临时数组taxAmounts，确保金额与原returnId正确关联。
• 第二步（Modify）：使用Jolt内置的sum函数，对每个对象的taxAmounts数组求和，结果存入returnTax字段。
• 第三步（Shift）：移除临时的taxAmounts字段，仅保留returnId和returnTax，生成符合预期的输出结构。

内容的提问来源于stack exchange，提问作者Gurveen Kaur Bagga