public static Optional<Integer> getStatePort(ServiceInfo service) {
        return service.getPorts().stream()
                      .filter(port -> port.getTags().contains("state"))
                      .map(PortInfo::getPort)
                      .findFirst();
    }
Get service generation of service at given URL
configserver/src/main/java/com/yahoo/vespa/config/server/application/ConfigConvergenceChecker.java