How to use script to show how many columns contain no data

Question

I have a requirement. There is a source which is excel file, from this excel file we need to load data in staging table. There are 5 mandatory columns those should not be null. We have used 'No Data Check' for this. The logic is if any of the above mentioned 5 columns  do not contain any record the record will be moved to without data. Up to this it is fine. Now the requirement is to show which column/columns does/do not contain data. We have used a script for this purpose as:
res=' '
res=input1[0]+'  :Failed due to null values in mandatory columns';
input1[1]=res;
output1=res;
But this is showing message as 'Failed due to null values in mandatory columns', which is a generic message. We need to show which column/columns does/do not contain value as 'Failed due to null values in mandatory column columnA, columnB, columnC'. Can anyone help me in this regard. Any kind of help is appreciated.

Answer 1

You could use the variable inputname1, which holds an array of the input attribute names to the script processor. For example:
var result = "";
var first = true;
for (i = 1; i < input1.length; i++) {
  if (input1[i] == null || input1[i] == "") {
    if (first) {
      first = false;
    } else {
      result += ", ";
    result += inputname1[i];
if (result.length > 0) {
  result = "Failed due to null values in the following mandatory columns: " + result;
output1 = result;
Regards,
Nick