code: func (g *GRPCServer) UpsertNode(ctx context.Context, server *services.ServerV2) (*services.KeepAlive, error) {
  	auth, err := g.authenticate(ctx)
  	if err != nil {
  		return nil, trail.ToGRPC(err)
  	}
  	keepAlive, err := auth.UpsertNode(server)
  	if err != nil {
  		return nil, trail.ToGRPC(err)
  	}
  	return keepAlive, nil
  }
docs: // UpsertNode upserts node