Jolt Transformation adding new key field using exisiting values in the JSON

Question

Input JSON is

{
  "name": "XYZ",
  "fields": [
    {
      "Code": "8000385",
      "Number": "9010005790",
      "docDate": "19-05-2022",
      "dueDate": "30-09-2022",
      "totValue": "209121.66",
      "taxAmt": "0",
      "docAmt": "3005797",
      "dueAmt": "3005797",
      "docType": "INV",
      "divCode": null,
      "finYear": "2022"
    }
  ]
}

the expected output is

{
  "name": "XYZ",
  "fields": [
    {
      "Code": "8000385",
      "Number": "9010005790",
      "docDate": "19-05-2022",
      "dueDate": "30-09-2022",
      "totValue": "209121.66",
      "taxAmt": "0",
      "docAmt": "3005797",
      "dueAmt": "3005797",
      "docType": "INV",
      "divCode": null,
      "finYear": "2022",
      "Key" : "8000385~9010005790~DOCX" // new field as concatenation of Code and Number
    }
  ]
}

Answer 1

You can use modify transformation along with a concat function such as

[
  {
    "operation": "modify-default-beta",
    "spec": {
      "fields": {
        "*": {
          "Key": "=concat(@(1,Code),'~',@(1,Number),'~DOCX')"
        }
      }
    }
  }
]

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