Merging JSONs based on condition

Question

Please help me to get the below output.

Based on Input1 and Input2 I have get the output. If Id matches then I need to have PATCH method if it does not then I need to have POST method.

If the Id ("ID": "123456") does not exist in input1 then it is POST else it is PATCH.

**Input1: **

{
  "prod": [
    {
      "Id": "123456",
      "value": "ABC"
    },
    {
      "Id": "123456",
      "value": "DEF"
    },
    {
      "Id": "987654",
      "value": "DEF"
    }
  ]
}

Input2:

{
  "ProdInfo": {
    "Prod": [
      {
        "Id": "123456",
        "value1": "LMN"
      },
      {
        "Id": "123456",
        "value1": "OPQ"
      },
      {
        "Id": "654321",
        "value1": "OPQ"
      }
    ]
  }
} 

Output:

{
  "output": [
    {
      "Request": [
        {
          "method": "PATCH",
          "body": {
            "ID": "123456",
            "Value": "ABC;DEF;LMN;OPQ"
          }
        },
        {
          "method": "POST",
          "body": {
            "ID": "654321",
            "Value": "OPQ"
          }
        }
      ]
    }
  ]
}

Answer 1

You can approach this problem by grouping by id, then use pluck() to get the key values in a way that can be mapped into the desired output. I added a function to encapsulate some of the inner complexity.

%dw 2.0
output application/json
var input1={
  "prod": [
    {
      "Id": "123456",
      "value": "ABC"
    },
    {
      "Id": "123456",
      "value": "DEF"
    }
  ]
}.prod groupBy ($.Id)

fun joinValues(v1,v2)=(v1 default [] ++ v2 default []) joinBy  ";"
---
{
    "output": [
        {
            Request: 
                payload.ProdInfo.Prod 
                    groupBy ($.Id)
                    pluck ((value, key, index) -> {
                        method: if (namesOf(input1) contains (key as String)) "PATCH" else "POST",
                        body: {
                            ID: key,
                            Value: joinValues(input1[key as String].*value, value.*value1)
                        }
                    })
        }
    ]
}

Input payload (equal to input2)

{
  "ProdInfo": {
    "Prod": [
      {
        "Id": "123456",
        "value1": "LMN"
      },
      {
        "Id": "123456",
        "value1": "OPQ"
      },
      {
        "Id": "654321",
        "value1": "OPQ"
      }
    ]
  }
} 

Output:

{
  "output": [
    {
      "Request": [
        {
          "method": "PATCH",
          "body": {
            "ID": "123456",
            "Value": "ABC;DEF;LMN;OPQ"
          }
        },
        {
          "method": "POST",
          "body": {
            "ID": "654321",
            "Value": "OPQ"
          }
        }
      ]
    }
  ]
}