code: public function usingCertificateAuthentication($certificate, $password = '')
      {
          $this->config->setCertificate($certificate);
          $this->config->setCertificatePassword($password);
          $this->config->setAuth(true);
  
          throw new Node\Builder\Exception('Riak over HTTP does not support Certificate Authentication.');
  
          //return $this;
      }
docs: usingCertificateAuthentication
  
  Build nodes with certificate authentication
  
  User authentication and access rules are only available in Riak versions 2 and above. To use this feature, TSL
  is required to communicate with your Riak nodes.
  
  CURRENTLY NOT SUPPORTED OVER THE RIAK HTTP API
  
  @param $certificate
  @param string $password
  
  @return $this
  @throws Builder\Exception