com.jkoolcloud.jesl.net.syslogd.JsonSyslogServerEventHandler.java Source code

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Here is the source code for com.jkoolcloud.jesl.net.syslogd.JsonSyslogServerEventHandler.java

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/*    
 *    Copyright (C) 2015, JKOOL LLC.
 *
 *    This library is free software; you can redistribute it and/or
 *    modify it under the terms of the GNU Lesser General Public
 *    License as published by the Free Software Foundation; either
 *    version 2.1 of the License, or (at your option) any later version.
 *
 *    This library is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *    Lesser General Public License for more details.
 *
 *    You should have received a copy of the GNU Lesser General Public
 *    License along with this library; if not, write to the Free Software
 *    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */
package com.jkoolcloud.jesl.net.syslogd;

import java.io.PrintStream;
import java.net.SocketAddress;
import java.util.Date;
import java.util.Map;

import org.apache.commons.lang3.StringEscapeUtils;
import org.joda.time.format.DateTimeFormatter;
import org.joda.time.format.ISODateTimeFormat;
import org.graylog2.syslog4j.impl.message.structured.StructuredSyslogMessage;
import org.graylog2.syslog4j.server.SyslogServerEventIF;
import org.graylog2.syslog4j.server.SyslogServerIF;
import org.graylog2.syslog4j.server.impl.event.printstream.PrintStreamSyslogServerEventHandler;
import org.graylog2.syslog4j.server.impl.event.structured.StructuredSyslogServerEvent;
import org.graylog2.syslog4j.util.SyslogUtility;

/**
 * This class implements simple syslog event handler that outputs
 * formatted syslog messages to a print stream in JSON format.
 * The output contains offset.usec which is time since last event in microseconds.
 * This field can be used to play back events in exact same time sequence. 
 * Event timestamp is formatted in ISO8601 format with UTC timezone.
 *
 * @version $Revision $
 */
class JsonSyslogServerEventHandler extends PrintStreamSyslogServerEventHandler {
    private static final long serialVersionUID = 8964244723777923472L;

    private long lastEvent = 0;
    DateTimeFormatter fmt = ISODateTimeFormat.dateTime().withZoneUTC();

    public JsonSyslogServerEventHandler(PrintStream out) {
        super(out);
    }

    @Override
    public void event(Object session, SyslogServerIF syslogServer, SocketAddress socketAddress,
            SyslogServerEventIF event) {
        long now = System.nanoTime();
        long offset = lastEvent == 0 ? 0 : (System.nanoTime() - lastEvent) / 1000;
        lastEvent = now;

        Date date = (event.getDate() == null ? new Date() : event.getDate());
        String timestamp = fmt.print(date.getTime());

        String facility = SyslogTNT4JEventHandler.getFacilityString(event.getFacility());
        String level = SyslogUtility.getLevelString(event.getLevel());
        String host = event.getHost();
        if (!(event instanceof StructuredSyslogServerEvent)) {
            this.stream.println("{\"offset.usec\":" + offset + ", \"host\":\"" + host + "\", \"facility\":\""
                    + facility + "\", \"timestamp\":\"" + timestamp + "\", \"level\":\"" + level + "\", \"msg\":\""
                    + StringEscapeUtils.escapeJson(event.getMessage()) + "\"}");
        } else {
            StructuredSyslogServerEvent sevent = (StructuredSyslogServerEvent) event;
            StructuredSyslogMessage sm = sevent.getStructuredMessage();
            Map<?, ?> arttrs = sm.getStructuredData();
            this.stream.println("{\"offset.usec\":" + offset + ", \"host\":\"" + host + "\", \"facility\":\""
                    + facility + "\", \"timestamp\":\"" + timestamp + "\", \"level\":\"" + level + "\", \"appl\":\""
                    + sevent.getApplicationName() + "\", \"mid\":\""
                    + (sm.getMessageId() != null ? sm.getMessageId() : "") + "\", \"pid\":"
                    + (sevent.getProcessId() != null && sevent.getProcessId().isEmpty() ? 0 : sevent.getProcessId())
                    + ", \"map.size\":" + ((arttrs != null) ? arttrs.size() : 0) + ", \"msg\":\""
                    + StringEscapeUtils.escapeJson(event.getMessage()) + "\"}");
        }
    }
}