func GetCaller(ctx context.Context) *RemoteClient {
	val, _ := ctx.Value(ctxCallerKey{}).(*RemoteClient)
	return val
}

// GetSubroute returns caller information from contexts provided to handlers.
func GetSubroute(ctx context.Context) string {
	val, _ := ctx.Value(ctxSubrouteKey{}).(string)
	return val
}

func setCaller(ctx context.Context, cl *RemoteClient) context.Context {