apollo-adminservice/src/main/java/com/ctrip/framework/apollo/adminservice/controller/ReleaseHistoryController.java/ReleaseHistoryController/transformReleaseHistory2DTO
class ReleaseHistoryController:  private ReleaseHistoryDTO transformReleaseHistory2DTO(ReleaseHistory releaseHistory) {
    ReleaseHistoryDTO dto = new ReleaseHistoryDTO();
    BeanUtils.copyProperties(releaseHistory, dto, "operationContext");
    dto.setOperationContext(GSON.fromJson(releaseHistory.getOperationContext(),
                                          configurationTypeReference));

    return dto;
  }