doGet json spreadsheet

function doGet(e) {
  var op = e.parameter.action;
  var ss = SpreadsheetApp.openById("spreadsheet_id");
  if (op == "getconfig")
    return get_config(e, ss);
}
function get_config(e,ss) {
  var sheet = ss.getSheetByName("Sheet1");
  var paket = e.parameter.paket;
  var flag = 0;
  var lr = sheet.getLastRow();
    for (var i = 1; i <= lr; i++) {
      var pkt = sheet.getRange(i, 5).getValue();
      if (pkt == paket){
        var urlapk = sheet.getRange(i, 3).getValue();
        var versiapp = sheet.getRange(i, 4).getValue();
        var personaads = sheet.getRange(i, 6).getValue();
        var judulnya = sheet.getRange(i, 7).getValue();
        var keterangannya = sheet.getRange(i, 8).getValue();
        var gambariklannya = sheet.getRange(i, 9).getValue();
        var linkpsnya = sheet.getRange(i, 10).getValue();
        var appid = sheet.getRange(i, 11).getValue();
        var banner = sheet.getRange(i, 12).getValue();
        var interstitial = sheet.getRange(i, 13).getValue();
        var nativeads = sheet.getRange(i, 14).getValue();
        var ngitungklik = sheet.getRange(i, 15).getValue();
        var result = JSON.stringify({
            "myads": {
              "urlapk": urlapk,
              "versiapp": versiapp,
              "personaads": personaads,
              "judulnya": judulnya,
              "keterangannya": keterangannya,
              "gambariklannya": gambariklannya,
              "linkpsnya": linkpsnya,
              "appid": appid,
              "banner": banner,
              "interstitial": interstitial,
              "nativeads": nativeads,
              "ngitungklik": ngitungklik
            }
          });
        flag = 1;
      }
    }
  if (flag == 0){
    var result = "gagal";
  }
  return ContentService.createTextOutput(result).setMimeType(ContentService.MimeType.JAVASCRIPT);
}