/*
* 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.apache.kafka.common.metrics;
import java.lang.management.ManagementFactory;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.management.Attribute;
import javax.management.AttributeList;
import javax.management.AttributeNotFoundException;
import javax.management.DynamicMBean;
import javax.management.InvalidAttributeValueException;
import javax.management.JMException;
import javax.management.MBeanAttributeInfo;
import javax.management.MBeanException;
import javax.management.MBeanInfo;
import javax.management.MBeanServer;
import javax.management.MalformedObjectNameException;
import javax.management.ObjectName;
import javax.management.ReflectionException;
import org.apache.kafka.common.KafkaException;
import org.apache.kafka.common.MetricName;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Register metrics in JMX as dynamic mbeans based on the metric names
*/
public class JmxReporter implements MetricsReporter {
private static final Logger log = LoggerFactory.getLogger(JmxReporter.class);
private static final Object LOCK = new Object();
private String prefix;
private final Map<String, KafkaMbean> mbeans = new HashMap<String, KafkaMbean>();
public JmxReporter() {
this("");
}
/**
* Create a JMX reporter that prefixes all metrics with the given string.
*/
public JmxReporter(String prefix) {
this.prefix = prefix;
}
@Override
public void configure(Map<String, ?> configs) {}
@Override
public void init(List<KafkaMetric> metrics) {
synchronized (LOCK) {
for (KafkaMetric metric : metrics)
addAttribute(metric);
for (KafkaMbean mbean : mbeans.values())
reregister(mbean);
}
}
@Override
public void metricChange(KafkaMetric metric) {
synchronized (LOCK) {
KafkaMbean mbean = addAttribute(metric);
reregister(mbean);
}
}
@Override
public void metricRemoval(KafkaMetric metric) {
synchronized (LOCK) {
KafkaMbean mbean = removeAttribute(metric);
if (mbean != null) {
if (mbean.metrics.isEmpty())
unregister(mbean);
else
reregister(mbean);
}
}
}
private KafkaMbean removeAttribute(KafkaMetric metric) {
MetricName metricName = metric.metricName();
String mBeanName = getMBeanName(metricName);
KafkaMbean mbean = this.mbeans.get(mBeanName);
if (mbean != null)
mbean.removeAttribute(metricName.name());
return mbean;
}
private KafkaMbean addAttribute(KafkaMetric metric) {
try {
MetricName metricName = metric.metricName();
String mBeanName = getMBeanName(metricName);
if (!this.mbeans.containsKey(mBeanName))
mbeans.put(mBeanName, new KafkaMbean(mBeanName));
KafkaMbean mbean = this.mbeans.get(mBeanName);
mbean.setAttribute(metricName.name(), metric);
return mbean;
} catch (JMException e) {
throw new KafkaException("Error creating mbean attribute for metricName :" + metric.metricName(), e);
}
}
/**
* @param metricName
* @return standard JMX MBean name in the following format domainName:type=metricType,key1=val1,key2=val2
*/
private String getMBeanName(MetricName metricName) {
StringBuilder mBeanName = new StringBuilder();
mBeanName.append(prefix);
mBeanName.append(":type=");
mBeanName.append(metricName.group());
for (Map.Entry<String, String> entry : metricName.tags().entrySet()) {
if (entry.getKey().length() <= 0 || entry.getValue().length() <= 0)
continue;
mBeanName.append(",");
mBeanName.append(entry.getKey());
mBeanName.append("=");
mBeanName.append(entry.getValue());
}
return mBeanName.toString();
}
public void close() {
synchronized (LOCK) {
for (KafkaMbean mbean : this.mbeans.values())
unregister(mbean);
}
}
private void unregister(KafkaMbean mbean) {
MBeanServer server = ManagementFactory.getPlatformMBeanServer();
try {
if (server.isRegistered(mbean.name()))
server.unregisterMBean(mbean.name());
} catch (JMException e) {
throw new KafkaException("Error unregistering mbean", e);
}
}
private void reregister(KafkaMbean mbean) {
unregister(mbean);
try {
ManagementFactory.getPlatformMBeanServer().registerMBean(mbean, mbean.name());
} catch (JMException e) {
throw new KafkaException("Error registering mbean " + mbean.name(), e);
}
}
private static class KafkaMbean implements DynamicMBean {
private final ObjectName objectName;
private final Map<String, KafkaMetric> metrics;
public KafkaMbean(String mbeanName) throws MalformedObjectNameException {
this.metrics = new HashMap<String, KafkaMetric>();
this.objectName = new ObjectName(mbeanName);
}
public ObjectName name() {
return objectName;
}
public void setAttribute(String name, KafkaMetric metric) {
this.metrics.put(name, metric);
}
@Override
public Object getAttribute(String name) throws AttributeNotFoundException, MBeanException, ReflectionException {
if (this.metrics.containsKey(name))
return this.metrics.get(name).value();
else
throw new AttributeNotFoundException("Could not find attribute " + name);
}
@Override
public AttributeList getAttributes(String[] names) {
try {
AttributeList list = new AttributeList();
for (String name : names)
list.add(new Attribute(name, getAttribute(name)));
return list;
} catch (Exception e) {
log.error("Error getting JMX attribute: ", e);
return new AttributeList();
}
}
public KafkaMetric removeAttribute(String name) {
return this.metrics.remove(name);
}
@Override
public MBeanInfo getMBeanInfo() {
MBeanAttributeInfo[] attrs = new MBeanAttributeInfo[metrics.size()];
int i = 0;
for (Map.Entry<String, KafkaMetric> entry : this.metrics.entrySet()) {
String attribute = entry.getKey();
KafkaMetric metric = entry.getValue();
attrs[i] = new MBeanAttributeInfo(attribute,
double.class.getName(),
metric.metricName().description(),
true,
false,
false);
i += 1;
}
return new MBeanInfo(this.getClass().getName(), "", attrs, null, null, null);
}
@Override
public Object invoke(String name, Object[] params, String[] sig) throws MBeanException, ReflectionException {
throw new UnsupportedOperationException("Set not allowed.");
}
@Override
public void setAttribute(Attribute attribute) throws AttributeNotFoundException,
InvalidAttributeValueException,
MBeanException,
ReflectionException {
throw new UnsupportedOperationException("Set not allowed.");
}
@Override
public AttributeList setAttributes(AttributeList list) {
throw new UnsupportedOperationException("Set not allowed.");
}
}
}