Function setupAjaxCaching

server_setup.js:219–231

/*Routing function implementations*/

var setupAjaxCaching = app => // IE/Edge are more aggressive about caching than other browsers, so we'll override their caching here.
// Assumes our CDN will override these with its own caching rules.
app.get('/db/*', function(req, res, next) {
  if (!req.xhr) { return next(); }
  // http://stackoverflow.com/questions/19999388/check-if-user-is-using-ie-with-jquery
  const userAgent = req.header('User-Agent') || "";
  if ((userAgent.indexOf('MSIE ') > 0) || !!userAgent.match(/Trident.*rv\:11\.|Edge\/\d+/)) {
    res.header('Cache-Control', 'no-cache, no-store, must-revalidate');
    res.header('Pragma', 'no-cache');
    res.header('Expires', 0);
  }
  return next();
});

var setupJavascript404s = function(app) {
  app.get('/javascripts/*', (req, res) => res.status(404).send('Not found'));