Jolt Transformation

Question

I am trying to write a jolt transformation for below input -

{ 
 "restaurantId": "ZZ4ORJDY3E",  
 "chainId": "a-b"
}

expected output is -

{
 "ZZ4ORJDY3E" : {
   "key" : "ZZ4ORJDY3E",
   "start" : "a",
   "end" : "b"
  }
}

My spec is -

[
  {
    "operation": "shift",
    "spec": {
      "@restaurantId": "@restaurantId.key",
      "chainId": {
        "*-*": {
          "$(0,1)": "@restaurantId.start",
          "$(0,2)": "@restaurantId.end"
        }
      }
    }
  }
]

The spec is not transforming as expected output. i want learn how to use attributes inside string parser.

Answer 1

Spec

[
  {
    "operation": "shift",
    "spec": {
      "restaurantId": {
        // match any value of restaurantId
        "*": {
          // write the value to of the key $ to the output
          // where the output is the "value of the key".key
          // kinda hokey
          "$": "&.key"
        }
      },
      "chainId": {
        "*-*": {
          // write each part of the chainId to the output
          //  at the value of restaurantId from back up the tree
          "$(0,1)": "@(3,restaurantId).start",
          "$(0,2)": "@(3,restaurantId).end"
        }
      }
    }
  }
]