scylla-jmx/src/main/java/org/apache/cassandra/gms/Gossiper.java
Amnon Heiman 8847343ebd Adding the Gossiper MBean implementation
This adds the implementation of the Gossiper MBean.

To test, run an urchin server, run the API and use jconsole to connect
to the API.

Signed-off-by: Amnon Heiman <amnon@cloudius-systems.com>
2015-05-25 18:36:12 +03:00

105 lines
4.0 KiB
Java

/*
* 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.
*/
/*
* Copyright 2015 Cloudius Systems
*
* Modified by Cloudius Systems
*/
package org.apache.cassandra.gms;
import java.lang.management.ManagementFactory;
import java.net.UnknownHostException;
import javax.management.MBeanServer;
import javax.management.ObjectName;
import javax.ws.rs.core.MultivaluedMap;
import com.cloudius.urchin.api.APIClient;
import com.sun.jersey.core.util.MultivaluedMapImpl;
/**
* This module is responsible for Gossiping information for the local endpoint.
* This abstraction maintains the list of live and dead endpoints. Periodically
* i.e. every 1 second this module chooses a random node and initiates a round
* of Gossip with it. A round of Gossip involves 3 rounds of messaging. For
* instance if node A wants to initiate a round of Gossip with node B it starts
* off by sending node B a GossipDigestSynMessage. Node B on receipt of this
* message sends node A a GossipDigestAckMessage. On receipt of this message
* node A sends node B a GossipDigestAck2Message which completes a round of
* Gossip. This module as and when it hears one of the three above mentioned
* messages updates the Failure Detector with the liveness information. Upon
* hearing a GossipShutdownMessage, this module will instantly mark the remote
* node as down in the Failure Detector.
*/
public class Gossiper implements GossiperMBean {
public static final String MBEAN_NAME = "org.apache.cassandra.net:type=Gossiper";
private static final java.util.logging.Logger logger = java.util.logging.Logger
.getLogger(Gossiper.class.getName());
private APIClient c = new APIClient();
public void log(String str) {
logger.info(str);
}
private static final Gossiper instance = new Gossiper();
public static Gossiper getInstance() {
return instance;
}
private Gossiper() {
// Register this instance with JMX
try {
MBeanServer mbs = ManagementFactory.getPlatformMBeanServer();
mbs.registerMBean(this, new ObjectName(MBEAN_NAME));
} catch (Exception e) {
throw new RuntimeException(e);
}
}
public long getEndpointDowntime(String address) throws UnknownHostException {
log(" getEndpointDowntime(String address) throws UnknownHostException");
return c.getLongValue("gossiper/downtime/" + address);
}
public int getCurrentGenerationNumber(String address)
throws UnknownHostException {
log(" getCurrentGenerationNumber(String address) throws UnknownHostException");
return c.getIntValue("gossiper/generation_number/" + address);
}
public void unsafeAssassinateEndpoint(String address)
throws UnknownHostException {
log(" unsafeAssassinateEndpoint(String address) throws UnknownHostException");
MultivaluedMap<String, String> queryParams = new MultivaluedMapImpl();
queryParams.add("unsafe", "True");
c.post("gossiper/assassinate/" + address, queryParams);
}
public void assassinateEndpoint(String address) throws UnknownHostException {
log(" assassinateEndpoint(String address) throws UnknownHostException");
c.post("gossiper/assassinate/" + address, null);
}
}