UrlFetchApp script with Zendesk (multiple pages)

fetch.js

function zd_get (cmd) {
  var url = ZD_BASE+cmd;
  var results =[];
  var service = getService();
  
  if (service.hasAccess()) {
    do {
      try {
        var response = UrlFetchApp.fetch(url, {headers: {'Authorization': 'Bearer ' + service.getAccessToken(),}});
      }
      catch (e) {
        return e;
         
      }
      var result = JSON.parse(response.getContentText());
      results.push(result);
      url = result['next_page'];
      Utilities.sleep(250); // give the server a break
      
    }  while (result['next_page'] !=null);
    return results;
  }
  else return null;

}