org.cloudata.core.common.metrics.GangliaContext31.java Source code

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Here is the source code for org.cloudata.core.common.metrics.GangliaContext31.java

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/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.cloudata.core.common.metrics;

import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.SocketAddress;
import java.net.SocketException;
import java.net.UnknownHostException;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 * @author jindolk
 *
 */
public class GangliaContext31 extends GangliaContext {

    String hostName = "UNKNOWN.example.com";

    private final Log LOG = LogFactory.getLog(this.getClass());

    public synchronized void startMonitoring() {
        try {
            hostName = InetAddress.getLocalHost().getCanonicalHostName();
        } catch (UnknownHostException e) {
        }

        try {
            datagramSocket = new DatagramSocket();
        } catch (SocketException se) {
            se.printStackTrace();
        }
        super.startMonitoring();

    }

    protected void emitMetric(String name, String type, String value) throws IOException {
        if (name == null) {
            LOG.warn("Metric was emitted with no name.");
            return;
        } else if (value == null) {
            LOG.warn("Metric name " + name + " was emitted with a null value.");
        } else if (type == null) {
            LOG.warn("Metric name " + name + ", value " + value + " has no type.");
        }

        LOG.debug("Emitting metric " + name + ", type " + type + ", value " + value + " from " + hostName);

        String units = getUnits(name);
        if (units == null) {
            LOG.warn("Metric name " + name + ", value " + value + " had 'null' units");
            units = "";
        }
        int slope = getSlope(name);
        int tmax = getTmax(name);
        int dmax = getDmax(name);
        offset = 0;
        String groupName = name.substring(0, name.lastIndexOf("."));

        // The following XDR recipe was done through a careful reading of
        // gm_protocol.x in Ganglia 3.1 and carefully examining the output of
        // the gmetric utility with strace.

        // First we send out a metadata message
        xdr_int(128); // metric_id = metadata_msg
        xdr_string(hostName); // hostname
        xdr_string(name); // metric name
        xdr_int(0); // spoof = False
        xdr_string(type); // metric type
        xdr_string(name); // metric name
        xdr_string(units); // units
        xdr_int(slope); // slope
        xdr_int(tmax); // tmax, the maximum time between metrics
        xdr_int(dmax); // dmax, the maximum data value

        xdr_int(1); /*Num of the entries in extra_value field for 
                      Ganglia 3.1.x*/
        xdr_string("GROUP"); /*Group attribute*/
        xdr_string(groupName); /*Group value*/

        for (SocketAddress socketAddress : metricsServers) {
            DatagramPacket packet = new DatagramPacket(buffer, offset, socketAddress);
            datagramSocket.send(packet);
        }

        // Now we send out a message with the actual value.
        // Technically, we only need to send out the metadata message once for
        // each metric, but I don't want to have to record which metrics we did and
        // did not send.
        offset = 0;
        xdr_int(133); // we are sending a string value
        xdr_string(hostName); // hostName
        xdr_string(name); // metric name
        xdr_int(0); // spoof = False
        xdr_string("%s"); // format field
        xdr_string(value); // metric value

        for (SocketAddress socketAddress : metricsServers) {
            DatagramPacket packet = new DatagramPacket(buffer, offset, socketAddress);
            datagramSocket.send(packet);
        }
    }

}