function doGet() {
  var fromLang = 'en';
  var toLang = 'fr';
  var rssFeed = 'http://feeds.labnol.org/';

  var feed = parseRSS(rssFeed, fromLang, toLang);
  return ContentService.createTextOutput(feed).setMimeType(ContentService.MimeType.RSS);
}

function parseRSS(feed, fromLang, toLang) {
  var id = Utilities.base64Encode(feed + fromLang + toLang);

  // Cache the RSS feeds for an hour
  var cache = CacheService.getPublicCache();
  var rss = cache.get(id);

  if (rss != null) {
    return rss;
  }

  var item, date, title, link, desc, guid;

  var txt = UrlFetchApp.fetch(feed).getContentText();
  var doc = Xml.parse(txt, false);

  title = doc.getElement().getElement('channel').getElement('title').getText();

  // The RSS Feed is translated using Google Translate
  rss = '';
  rss += '';
  rss += LanguageApp.translate(title, fromLang, toLang);
  rss += ' (' + title + ')';

  var items = doc.getElement().getElement('channel').getElements('item');

  // Parsing single items in the RSS Feed
  for (var i in items) {
    try {
      item = items[i];

      title = item.getElement('title').getText();
      link = item.getElement('link').getText();
      date = item.getElement('pubDate').getText();
      desc = item.getElement('description').getText();

      guid = Utilities.base64Encode(link + fromLang + toLang);

      title = LanguageApp.translate(title, fromLang, toLang);
      desc = LanguageApp.translate(desc, fromLang, toLang, { contentType: 'html' });

      rss += '';
      rss += '  ' + title + '';
      rss += '  ' + link + '';
      rss += '  ' + date + '';
      rss += '  ' + guid + '';
      rss += '  ';
      rss += '';
    } catch (e) {
      Logger.log(e);
    }
  }

  rss += '';

  cache.put(id, rss, 3600);
  return rss;
}