OIC: Manage response payload having empty key-name

Hi All,

I'm trying to integrate data from an API call.
The reguresponse payload looks like:

"response": {
      "goals": {    
           "for": {  
           "minute": {
                "0-15": {
                    "total": null,
                    "percentage": null
                },
                "16-30": {
                    "total": null,
                    "percentage": null
                },
                "31-45": {
                    "total": 3,
                    "percentage": "21.43%"
                },
                "46-60": {
                    "total": 3,
                    "percentage": "21.43%"
                },
                "61-75": {
                    "total": 1,
                    "percentage": "7.14%"
                },
                "76-90": {
                    "total": null,
                    "percentage": null
                }
            }
        }
}

But sometimes there is an additional key with an empty name ("") and the payload looks like:

"response": {

"goals": {

"for": {           

          "minute": {
                "0-15": {
                    "total": null,
                    "percentage": null
                },
                "16-30": {
                    "total": null,
                    "percentage": null
                },
                "31-45": {
                    "total": 3,
                    "percentage": "21.43%"
                },
                "46-60": {
                    "total": 3,
                    "percentage": "21.43%"
                },
                "61-75": {
                    "total": 1,
                    "percentage": "7.14%"
                },
                "76-90": {
                    "total": null,
                    "percentage": null
                },
                "": {
                    "total": 5,
                    "percentage": "35.71%"
                }
            }
        }
 }

I want to check if the incoming response has an element with empty name and then map "total" and "percentage" attributes to the right target.