apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/component/AdminServiceAddressLocator.java/AdminServiceAddressLocator/getServiceList
class AdminServiceAddressLocator:  public List<ServiceDTO> getServiceList(Env env) {
    List<ServiceDTO> services = cache.get(env);
    if (CollectionUtils.isEmpty(services)) {
      return Collections.emptyList();
    }
    List<ServiceDTO> randomConfigServices = Lists.newArrayList(services);
    Collections.shuffle(randomConfigServices);
    return randomConfigServices;
  }