code: func (s *Store) SetServiceLeader(service, id string) error {
  	// Serialize command.
  	cmd, err := json.Marshal(&setLeaderCommand{
  		Service: service,
  		ID:      id,
  	})
  	if err != nil {
  		return err
  	}
  
  	if _, err := s.raftApply(setLeaderCommandType, cmd); err != nil {
  		return err
  	}
  	return nil
  }
docs: // SetServiceLeader manually sets the leader for a service.