@Override
  public  PersistedTopologyRequest persistTopologyRequest(BaseClusterRequest request) {
    TopologyRequestEntity requestEntity = toEntity(request);
    topologyRequestDAO.create(requestEntity);
    return new PersistedTopologyRequest(requestEntity.getId(), request);
  }
Implementation which uses Ambari Database DAO and Entity objects for persistence
of topology related information.
ambari-server/src/main/java/org/apache/ambari/server/topology/PersistedStateImpl.java