如何在MuleSoft DataWeave中过滤符合指定条件的嵌套数组？

需求说明 #

从给定的JSON payload中，筛选出offers数组下所有category.characters数组里满足name为WBB且priority为1的元素，最终得到单个符合条件的对象。

原始Payload #

{
 "status": "Success",
 "offers": [
  {
   "id": 100,
   "name": "Test1",
   "category": {
    "characters": [
     {
      "name": "WBB",
      "priority": 1
     },
     {
      "name": "ILL",
      "priority": 2
     }
    ]
   }
  },
  {
   "id": 200,
   "name": "Test2",
   "category": {
    "characters": [
     {
      "name": "WLS",
      "priority": 1
     },
     {
      "name": "DLL",
      "priority": 2
     }
    ]
   }
  },
  {
   "id": 300,
   "name": "Test3",
   "category": {
    "characters": [
     {
      "name": "INTERNET",
      "priority": 1
     },
     {
      "name": "FIBER",
      "priority": 2
     }
    ]
   }
  }
 ]
}

预期输出 #

{
 "name": "WBB",
 "priority": 1
}

解决方案（DataWeave 2.0） #

在MuleSoft的Transform Message组件中使用以下DataWeave代码：

%dw 2.0
output application/json
---
flatten(payload.offers.category.characters) 
    filter ($.name == "WBB" and $.priority == 1) 
    [0]

代码解释 #

• flatten(payload.offers.category.characters)：将所有offer下嵌套的characters数组展开成一维数组，简化遍历逻辑
• filter ($.name == "WBB" and $.priority == 1)：筛选出同时满足两个条件的元素
• [0]：取第一个匹配的元素，确保输出为单个对象（若存在多个匹配项，可移除[0]返回匹配元素数组）

内容的提问来源于stack exchange，提问作者Krish