buf.append(",\"log.level\":\"INFO\"");
        buf.append(",\"ecs.version\":\"").append(ecsVersion).append('"');
        buf.append(",\"service.name\":\"").append(ecsServiceName).append('"');
        buf.append(",\"event.dataset\":\"").append(ecsEventDataset).append('"');
        buf.append(",\"process.thread.name\":\"").append(StringEscapeUtils.escapeJson(Thread.currentThread().getName())).append('"');

    }

    @Override
    public LogEvent rewrite(final LogEvent event) {
        final String loggerName = event.getLoggerName();
        if (loggerName == null) {
            return event;
        }
        for (final String name : loggerNames) {
            if (loggerName.startsWith(name)) {
                final Level sourceLevel = event.getLevel();
                if (sourceLevel != Level.ERROR) {

    //                                  Application Variable
    //                                  --------------------
    /**
     * Set the value of hostname, used in parameter comment. <br>
     * Even if empty string, treated as empty plainly. So "IF pmb != null" is false if empty.
     * @param hostname The parameter value of hostname. (NotNull)
     */
    public void setHostname(String hostname) {

        direction.directLoggingTitle(fessConfig.getDomainTitle(), fessConfig.getEnvironmentTitle());

        // this configuration is on sea_env.properties because it has no influence to production
        // even if you set true manually and forget to set false back
        direction.directFrameworkDebug(fessConfig.isFrameworkDebug()); // basically false

        // you can add your own process when your application is booting or closing

     * Even if empty string, treated as empty plainly. So "IF pmb != null" is false if empty.
     * @param hostname The parameter value of hostname. (NotNull)
     */
    public void setHostname(String hostname) {
        registerVariable("hostname", hostname);
    }

    /**
     * Set the value of clustername, used in parameter comment. <br>