Google Apps Script でウェブサイトの死活監視をする

function check_site(url)
{
  var result;
  try{
    var test = UrlFetchApp.fetch(url);
    result = test.getResponseCode();
  } catch(e){
    result =  0;
  }
  
  if(result != 200){
    MailApp.sendEmail("test@sample.com", "Error", url + " is down.");
  }
  return result;
}