apollo-portal/src/main/java/com/ctrip/framework/apollo/openapi/server/service/ServerReleaseOpenApiService.java/ServerReleaseOpenApiService/getLatestActiveRelease
class ServerReleaseOpenApiService:  @Override
  public OpenReleaseDTO getLatestActiveRelease(String appId, String env, String clusterName,
      String namespaceName) {
    ReleaseDTO releaseDTO = releaseService.loadLatestRelease(appId, Env.valueOf
        (env), clusterName, namespaceName);
    if (releaseDTO == null) {
      return null;
    }

    return OpenApiBeanUtils.transformFromReleaseDTO(releaseDTO);
  }