apache-nifi - NiFi 中的 JoltTransformJSON 处理器(没有任何父标签的 json)

Question

我需要使用 Nifi 中的 JoltTransformJSON 转换 JSON 数据，这是我用于转换的规范:

[{
"operation": "shift",
"spec": {
    "*": {
        "Header": {
            "readOn": "created_date_time",
            "fileName": "readFile"
        },
        "Data": {
            "id": "Id",
            "first_name": "First_Name",
            "last_name": "Last_Name",
        }
    }
}}]

我的输入数据:

[{
"Header": {
    "readOn": "2017/04/18 10:55:05",
    "fileName": "sample1.csv",
    "recordNum": 1
},
"Data": {
    "last_name": "Martin",
    "id": 21,
    "first_name": "Clarence"
}
}, {
"Header": {
    "readOn": "2017/04/18 10:55:05",
    "fileName": "sample.csv",
    "recordNum": 2
},
"Data": {
    "last_name": "Graham",
    "id": 22,
    "first_name": "Walter"
}
}]

输出我得到的:

{
"created_date_time": ["2017/04/18 10:55:05", "2017/04/18 10:55:05"],
"readFile": ["sample1.csv", "sample2.csv"],
"Id": [21, 22],
"First_Name": ["Clarence", "Walter"],
"Last_Name": ["Martin", "Graham"]
}

所需的输出:

[{
"recordNum": 1,
"Header": {
    "created_date_time": "2017/04/18 10:55:05",
    "readFile": "getusroi.csv"
},
"Data": {
    "Last_Name": "Martin",
    "Id": 21,
    "First_Name": "Clarence"
}
}, {
"recordNum": 2,
"Header": {
    "created_date_time": "2017/04/18 10:55:05",
    "readFile": "getusroi.csv"
},
"Data": {
    "Last_Name": "Graham",
    "Id": 22,
    "First_Name": "Walter"
}
}]

问题:有人可以指导我在哪些地方需要更改我的颠簸规范以获得所需的转换输出。

Answer 1

诀窍是沿着树往回走，直到到达数组中的元素，然后您可以在目标中引用该索引。试试这个规范:

[
  {
    "operation": "shift",
    "spec": {
      "*": {
        "Header": {
          "recordNum": "[&2].recordNum",
          "readOn": "[&2].&1.created_date_time",
          "fileName": "[&2].&1.readFile"
        },
        "Data": {
          "id": "[&2].&1.Id",
          "first_name": "[&2].&1.First_Name",
          "last_name": "[&2].&1.Last_Name"
        }
      }
    }
  }
]