revision

type Backend interface {
	// SetCurrentRevision sets the revision of backend
	SetCurrentRevision(uint64)
}

type LeaderRevision struct {
	// Revision is the revision of leader
	Revision uint64
}

type RevisionSyncer interface {
	// SyncReadRevision  fetch the latest revision from leader and set it in backend
	// if this instance is follower. otherwise, do nothing.
	SyncReadRevision() error

	// Close closes syncer
	Close() error
}