/*
* Druid - a distributed column store.
* Copyright (C) 2012, 2013 Metamarkets Group Inc.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
package io.druid.curator.discovery;
import com.metamx.common.lifecycle.LifecycleStart;
import com.metamx.common.lifecycle.LifecycleStop;
import com.metamx.common.logger.Logger;
import io.druid.client.selector.DiscoverySelector;
import io.druid.client.selector.Server;
import org.apache.curator.x.discovery.ServiceInstance;
import org.apache.curator.x.discovery.ServiceProvider;
import java.io.IOException;
/**
*/
public class ServerDiscoverySelector implements DiscoverySelector<Server>
{
private static final Logger log = new Logger(ServerDiscoverySelector.class);
private final ServiceProvider serviceProvider;
public ServerDiscoverySelector(ServiceProvider serviceProvider)
{
this.serviceProvider = serviceProvider;
}
@Override
public Server pick()
{
final ServiceInstance instance;
try {
instance = serviceProvider.getInstance();
}
catch (Exception e) {
log.info(e, "Exception getting instance");
return null;
}
if (instance == null) {
log.error("No server instance found");
return null;
}
return new Server()
{
@Override
public String getHost()
{
return String.format("%s:%d", getAddress(), getPort());
}
@Override
public String getAddress()
{
return instance.getAddress();
}
@Override
public int getPort()
{
return instance.getPort();
}
@Override
public String getScheme()
{
return "http";
}
};
}
@LifecycleStart
public void start() throws Exception
{
serviceProvider.start();
}
@LifecycleStop
public void stop() throws IOException
{
serviceProvider.close();
}
}