exports.register = async (req, res, next) => {

  let key;
  await crypto.pbkdf2('secret', 'salt', 100000, 64, 'sha512', (err, derivedKey) => {
    if (err){
      console.log(err)
      console.log('err')
    }
    key = derivedKey.toString('hex')
    console.log('callback'+key)
  })

  console.log('post-await'+key)

}