Javascript in application integration

[rish]

I am trying to map a json to big query connector but I need subset of fields from json to map to big query so I wrote a javascript to map them. I am getting a syntax error at for loop. I dont understand why. Is for loop available in application integration`s javascript?. I thoroughly read javascript doc for application integration but it provides limited info. Can I know which version of js it is?? IS there a different way of doing it??

Below is my code to extract allowed fields from salesforce json

function executeScript(event) {
  const mapped = {};
  //bqColumns is string array variable  with all required columns
  for(const key in event.getParameter("bqColumns")) {
    //loadBq is the input json which needs to be filtered
    event.setParameter(mapped.key ,event.getParameter("loadBq").key)
  }
  //ouput to be loaded to bq table
  event.setParameter("new", event.getParameter("mapped"));
}

[rohitjangid]

Hi rish

I can see that on line 6, you should access the mapping as `mapped[key]` instead of `mapped.key`. Which could be causing error. Another thing I noticed is you are setting individual parameters within your loop. I am not sure if that is the intended thing you are trying to do. 

Can you share error message that you are getting?

[rish]

I Just implemented the mapped[key] and I read the doc and it mentioned to use setParamater when setting values. I tried mapped[key] = 

event.getParameter("fetchSf")[key] too and the error is same. I am attaching the code I used and its corresponding logs Sc below