function saveData(folder, fileName, contents) {
  file = folder.createFile(fileName, contents);
}

function helloWorld() {
  var folders = DriveApp.getFoldersByName("Drafts");
  var folder = folders.next();
  var drafts = GmailApp.getDrafts(); // The first draft message in the drafts folder
  drafts.forEach(function(draft){
    var message = draft.getMessage();
    var contents = message.getSubject() + '\n' + message.getBody();
    saveData(folder, "Draft.html", contents);

  });
}