code: func (ns *NatsRPCServer) onSessionBind(ctx context.Context, s *session.Session) error {
  	if ns.server.Frontend {
  		subu, err := ns.subscribeToUserMessages(s.UID(), ns.server.Type)
  		if err != nil {
  			return err
  		}
  		subk, err := ns.subscribeToUserKickChannel(s.UID(), ns.server.Type)
  		if err != nil {
  			return err
  		}
  		s.Subscriptions = []*nats.Subscription{subu, subk}
  	}
  	return nil
  }
docs: // onSessionBind should be called on each session bind