Split string by values and fill JSON with it (NiFi)

Question

I've a JSON:

[
  {
    "id": 1,
    "status": 0
  },
  {
    "id": 2,
    "status": 0
  },
  {
    "id": 3,
    "status": 1
  }
]

And I've an attribute task-ids. It's a string with comma separated values. For example it can be: 500, 501, 502, or 765, 780, 790 or 10, 11, 12 etc. Numbers can be completely random, but their order and amount matches with order and amount of json objects. I mean first element from string is always should go to the first object in json, second to second, etc. For the first case 500 should go to object with id = 1, 501 to 2, 502 to 3. Order in this string equals to order of objects. So I expect this:

[
  {
    "id": 1,
    "status": 0,
    "taskId": 500
  },
  {
    "id": 2,
    "status": 0,
    "taskId": 501
  },
  {
    "id": 3,
    "status": 1,
    "taskId": 502
  }
]

My task is: split string from an attribute and fill source JSON by these values from string. Order is maintained. First element from an attribute should go to first element of JSON, etc.

I wrote simple Groovy script for this task, but maybe there is another option to solve this task (without using scripts)?

def numbersString = flowFile.getAttribute("task-ids");
def numbersArray = numbersString.split(',').collect { it as Integer }

for (int i = 0; i < numbersArray.size(); i++) {
    jsonArray[i].taskId = numbersArray[i]
}

Answer 1

You might use intSum function within a modify transformation such as

[
  {
    "operation": "modify-overwrite-beta",
    "spec": {
      "*": {
        "taskId": "=intSum(@(1,id),499)"
      }
    }
  }
]

the demo on the site http://jolt-demo.appspot.com/ is :