apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/service/ReleaseHistoryService.java/ReleaseHistoryService/findLatestByReleaseIdAndOperation
class ReleaseHistoryService:  public ReleaseHistoryBO findLatestByReleaseIdAndOperation(Env env, long releaseId, int operation){
    PageDTO<ReleaseHistoryDTO> pageDTO = releaseHistoryAPI.findByReleaseIdAndOperation(env, releaseId, operation, 0, 1);
    if (pageDTO != null && pageDTO.hasContent()){
      ReleaseHistoryDTO releaseHistory = pageDTO.getContent().get(0);
      ReleaseDTO release = releaseService.findReleaseById(env, releaseHistory.getReleaseId());
      return transformReleaseHistoryDTO2BO(releaseHistory, release);
    }

    return null;
  }