code: func (s *Store) EnsureService(idx uint64, node string, svc *structs.NodeService) error {
  	tx := s.db.Txn(true)
  	defer tx.Abort()
  
  	// Call the service registration upsert
  	if err := s.ensureServiceTxn(tx, idx, node, svc); err != nil {
  		return err
  	}
  
  	tx.Commit()
  	return nil
  }
docs: // EnsureService is called to upsert creation of a given NodeService.