apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/spi/defaultimpl/DefaultSsoHeartbeatHandler.java/DefaultSsoHeartbeatHandler/doHeartbeat
class DefaultSsoHeartbeatHandler:  @Override
  public void doHeartbeat(HttpServletRequest request, HttpServletResponse response) {
    try {
        response.sendRedirect("default_sso_heartbeat.html");
    } catch (IOException ignore) {
    }
  }