[SOLVED] Extract key from object and match that key in array of object and extract value using jolt transform

Extract key from object and match that key in array of object and extract value using jolt transform

{
  "reason": {
    "id": 1234,
    "value": "Date changed",
    "key": "2124"
  },
  "updatedEntity": [
    {
      "key": "2124",
      "value": "US california"
    },
    {
      "key": "2123",
      "value": "Dallas"
    },
    {
      "key": "2122",
      "value": "Texas"
    }
  ]
}

i have input data as stated above. I want to apply jolt transformation in such way the key in reason object matches key in updatedEntity array and in output i ll get value..

{
  "payload" :"US california"
}

i have written jolt spec but seems it is not working

[
  {
    "operation": "shift",
    "spec": {
      "reason": {
        "key": "reasonKey"
      },
      "updatedEntity": {
        "*": {
          "key": {
            "reasonKey": {
              "@(2,value)": "payload"
            }
          }
        }
      }
    }
  }
]

Solution

You can use the following transformation spec :

[
  {
    "operation": "shift",
    "spec": {
      "updatedEntity": {
        "*": {
          "@value": "@key"
        }
      },
      "@reason.key": "payload"
    }
  },
  {
    "operation": "shift",
    "spec": {
      "payload": {
        "*": {
          "@2,&": "&2"//match payload's value @2,& with the key &2
        }
      }
    }
  }
]

the demo on the site Jolt Transform Demo Using v0.1.1 is :