code: func (s *Server) handleQuestion(q dns.Question, resp *dns.Msg) error {
  	if s.service == nil {
  		return nil
  	}
  
  	switch q.Name {
  	case s.service.ServiceName():
  		s.composeBrowsingAnswers(resp, s.ttl)
  	case s.service.ServiceInstanceName():
  		s.composeLookupAnswers(resp, s.ttl)
  	case s.service.ServiceTypeName():
  		s.serviceTypeName(resp, s.ttl)
  	}
  
  	return nil
  }
docs: // handleQuestion is used to handle an incoming question