api.go
func (r *Raft) String() string {
	return fmt.Sprintf("Node at %s [%v]", r.localAddr, r.getState())
}
func (r *Raft) String() string {
	return fmt.Sprintf("Node at %s [%v]", r.localAddr, r.getState())
}
// String returns a string representation of this Raft node.