apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/service/ConfigsImportService.java/ConfigsImportService/importCluster
class ConfigsImportService:  private void importCluster(String clusterInfo, List<Env> importEnvs) {
    ClusterDTO toImportCluster = gson.fromJson(clusterInfo, ClusterDTO.class);

    toImportCluster.setDataChangeCreatedBy(currentUser);
    toImportCluster.setDataChangeLastModifiedBy(currentUser);
    toImportCluster.setDataChangeCreatedTime(new Date());
    toImportCluster.setDataChangeLastModifiedTime(new Date());

    String appId = toImportCluster.getAppId();
    String clusterName = toImportCluster.getName();

    importEnvs.parallelStream().forEach(env -> {
      try {
        clusterService.loadCluster(appId, env, clusterName);
      } catch (Exception e) {
        //not existed
        clusterService.createCluster(env, toImportCluster);
      }
    });
  }