g-script

function doGet(e){
  var keyVals = parseValues(e);
  addRow(keyVals);
  return ContentService.createTextOutput('Success!');
}

function parseValues(e){
  var rawKeyVals = JSON.stringify(e.parameter).split('"');
  var parsedKeys = [];
  var parsedVals = [];
  for(i=3;i<rawKeyVals.length;i=i+4){
    parsedVals.push(rawKeyVals[i]);
  }
  for(i=1;i<rawKeyVals.length;i=i+4){
    parsedKeys.push(rawKeyVals[i]);
  }
  var keyVals = [parsedKeys, parsedVals];
  return keyVals;
}

function addRow(keyVals){
  var keys = keyVals[0];
  var vals = keyVals[1];
  var ss = SpreadsheetApp.openByUrl("**YOUR SPREADSHEETS URL GOES HERE**");
  var sheets = ss.getSheets();
  var sheet = sheets[0];
  var lastRow = sheet.getLastRow();
  var lastCol = sheet.getLastColumn();
  //get column labels (row 1 values)
  var headerVals = sheet.getRange(1,1,1,lastCol).getValues();
  //create correct length array for new row values by cloning headerVals[]
  var newRowVals = headerVals[0].slice(0);
  //add new values to newRowVals. add 'no data' if no data
  for(i=0;i<headerVals[0].length;i++){
    var index = keys.indexOf(headerVals[0][i]);
    if(index >= 0){
      newRowVals[i] = vals[index];
    }else{
      newRowVals[i] = 'no data';
    }
  }
  //add new (blank) row to spreadsheet after the header row, then populate row with new data
  sheet.insertRowAfter(1);
  var insertRange = sheet.getRange(2,1,1,newRowVals.length);
  var insertValues = [newRowVals];
  insertRange.setValues(insertValues);
}