fs.readfile

fs.readdir(source, function (err, files) {
    if (err) {
      console.log('Error finding files: ' + err)
    } else {
      files.forEach(function (filename, fileIndex) {
        console.log(filename)
        gm(source + filename).size(function (err, values) {
          if (err) {
            }.bind(this))
          }
        })
      }
 });
  fs.readdir(source, function (err, files) { }