// List all files in a directory and reverse the list (newest on top)

async.waterfall([
  function(cb) {
    var filenames = []
    fs.readdir('/dir', function(err, files) {
      if (err) return;
      for(var i = 0; i < files.length; i++){
        filenames.push(files[i])
        if(i === files.length - 1){
          cb(null, filenames.reverse());
        }
      }
    });
  },
    function(filenames) {
      return res.status(200).json(filenames)
    }
]);