/*
* The MIT License
*
* Copyright (c) 2004-2009, Sun Microsystems, Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package hudson;
import hudson.model.Hudson;
import jenkins.model.Jenkins;
import hudson.util.OneShotEvent;
import java.io.IOException;
import java.net.BindException;
import java.net.DatagramPacket;
import java.net.InetAddress;
import java.net.MulticastSocket;
import java.net.SocketAddress;
import java.net.UnknownHostException;
import java.nio.channels.ClosedByInterruptException;
import java.util.logging.Level;
import java.util.logging.Logger;
/**
* Monitors a UDP multicast broadcast and respond with the location of the Hudson service.
*
* <p>
* Useful for auto-discovery of Hudson in the network.
*
* @author Kohsuke Kawaguchi
*/
public class UDPBroadcastThread extends Thread {
private final Jenkins jenkins;
public final OneShotEvent ready = new OneShotEvent();
private MulticastSocket mcs;
private boolean shutdown;
/**
* @deprecated as of 1.416
* Use {@link #UDPBroadcastThread(Jenkins)}
*/
public UDPBroadcastThread(Hudson jenkins) throws IOException {
this((Jenkins)jenkins);
}
public UDPBroadcastThread(Jenkins jenkins) throws IOException {
super("Jenkins UDP "+PORT+" monitoring thread");
this.jenkins = jenkins;
mcs = new MulticastSocket(PORT);
}
@Override
public void run() {
try {
mcs.joinGroup(MULTICAST);
ready.signal();
while(true) {
byte[] buf = new byte[2048];
DatagramPacket p = new DatagramPacket(buf,buf.length);
mcs.receive(p);
SocketAddress sender = p.getSocketAddress();
// prepare a response
TcpSlaveAgentListener tal = jenkins.getTcpSlaveAgentListener();
StringBuilder rsp = new StringBuilder("<hudson>");
tag(rsp,"version", Jenkins.VERSION);
tag(rsp,"url", jenkins.getRootUrl());
tag(rsp,"server-id", Util.getDigestOf(jenkins.getSecretKey()));
tag(rsp,"slave-port",tal==null?null:tal.getPort());
for (UDPBroadcastFragment f : UDPBroadcastFragment.all())
f.buildFragment(rsp,sender);
rsp.append("</hudson>");
byte[] response = rsp.toString().getBytes("UTF-8");
mcs.send(new DatagramPacket(response,response.length,sender));
}
} catch (ClosedByInterruptException e) {
// shut down
} catch (BindException e) {
// if we failed to listen to UDP, just silently abandon it, as a stack trace
// makes people unnecessarily concerned, for a feature that currently does no good.
LOGGER.log(Level.WARNING, "Failed to listen to UDP port "+PORT,e);
} catch (IOException e) {
if (shutdown) return; // forcibly closed
LOGGER.log(Level.WARNING, "UDP handling problem",e);
}
}
private void tag(StringBuilder buf, String tag, Object value) {
if(value==null) return;
buf.append('<').append(tag).append('>').append(value).append("</").append(tag).append('>');
}
public void shutdown() {
shutdown = true;
mcs.close();
interrupt();
}
public static final int PORT = Integer.getInteger("hudson.udp",33848);
private static final Logger LOGGER = Logger.getLogger(UDPBroadcastThread.class.getName());
/**
* Multicast socket address.
*/
public static InetAddress MULTICAST;
static {
try {
MULTICAST = InetAddress.getByAddress(new byte[]{(byte)239, (byte)77, (byte)124, (byte)213});
} catch (UnknownHostException e) {
throw new Error(e);
}
}
}