pick.js

function pick(obj, ...keys) {
  if (typeof obj !== 'object') return;

  var result = {};
  for (var key of Object.keys(obj)) {
    if (keys.indexOf(key) >= 0) result[key] = obj[key];
  }

  return result;
}

var obj = { one: 1, two: 2, three: 3 }
console.log(pick(obj, ['one', 'two']));