change user password in LDAP

ldap_change_password.js

let changePassword = (userId, passwordOld, passwordNew) => {
  return new Promise((resolve, reject) => {

    const ldapClient = ldapjs.createClient(ldapOptions);

    // 1
    ldapClient.bind(
      'cn=' + userId + ',' + ldapConfig.domain,
      passwordOld,
      err => {
        if (err) return reject(err);

        // 2
        ldapClient.modify(getDomainString(userId),
          [
            new ldapjs.Change({
              operation: 'replace',
              modification: {
                userPassword: passwordNew
              }
            })
          ],
          (err) => {
            if (err) reject(err);
            return resolve(true);
          }
        );
      }
    );
  }
}