apollo-portal/src/main/java/com/ctrip/framework/apollo/openapi/util/ConsumerAuthUtil.java/ConsumerAuthUtil/retrieveConsumerId
class ConsumerAuthUtil:  public long retrieveConsumerId(HttpServletRequest request) {
    Object value = request.getAttribute(CONSUMER_ID);

    try {
      return Long.parseLong(value.toString());
    } catch (Throwable ex) {
      throw new IllegalStateException("No consumer id!", ex);
    }
  }