Converting google spreadsheet to XLSX or ODS using GAS

Question

I want to convert a few google spreadsheets to Excel (xlsx preferred).
I\'ve read several threads about how to achieve this, but I can\'t get it running.
Amongst the

Answer 1

You can use the Advanced Drive Service to get the export URL and use the script's OAuth2 token to download the file.

function exportAsExcel(spreadsheetId) {
  var file = Drive.Files.get(spreadsheetId);
  var url = file.exportLinks['application/vnd.openxmlformats-officedocument.spreadsheetml.sheet'];
  var token = ScriptApp.getOAuthToken();
  var response = UrlFetchApp.fetch(url, {
    headers: {
      'Authorization': 'Bearer ' +  token
    }
  });
  return response.getBlob();
}

function test() {
  var spreadsheetId = 'SPREADSHEET ID HERE';
  DriveApp.createFile(exportAsExcel(spreadsheetId));
}