/**
Copyright (C) SYSTAP, LLC DBA Blazegraph 2006-2016. All rights reserved.
Contact:
SYSTAP, LLC DBA Blazegraph
2501 Calvert ST NW #106
Washington, DC 20008
licenses@blazegraph.com
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; version 2 of the License.
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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
package com.bigdata.journal;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import org.apache.log4j.Logger;
import com.bigdata.counters.AbstractStatisticsCollector;
import com.bigdata.counters.CounterSet;
import com.bigdata.counters.httpd.CounterSetHTTPD;
/**
* {@link CounterSetHTTPD} plug-in.
*
* @author <a href="mailto:thompsonbry@users.sourceforge.net">Bryan Thompson</a>
*/
@SuppressWarnings("deprecation")
public class HttpPlugin implements IPlugIn<Journal, CounterSetHTTPD> {
private static final Logger log = Logger.getLogger(HttpPlugin.class);
public interface Options {
/**
* Integer option specifies the port on which an httpd service will be
* started that exposes the {@link CounterSet} for the client (default
* {@value #DEFAULT_HTTPD_PORT}). When ZERO (0), a random port will be
* used and the actual port selected may be discovered using
* {@link Journal#getHttpdURL()}. The httpd service may be disabled by
* specifying <code>-1</code> as the port.
*/
String HTTPD_PORT = Journal.class.getName() + ".httpdPort";
/**
* The default http service port is <code>-1</code>, which means
* performance counter reporting is disabled by default.
*/
String DEFAULT_HTTPD_PORT = "-1";
}
/**
* httpd reporting the live counters -or- <code>null</code> if not enabled.
* <p>
* Note: Guarded by <code>synchronized(this)</code>.
*
* @see Options#HTTPD_PORT
*/
private CounterSetHTTPD httpd = null;
/**
* The URL that may be used to access the httpd service exposed by this
* client -or- <code>null</code> if not enabled.
* <p>
* Note: Guarded by <code>synchronized(this)</code>.
*/
private String httpdURL = null;
/**
* {@inheritDoc}
* <p>
* Start the local httpd service (if enabled). The service is started on the
* {@link Journal#getHttpdPort()}, on a randomly assigned port if the port
* is <code>0</code>, or NOT started if the port is <code>-1</code>. If the
* service is started, then the URL for the service is reported to the load
* balancer and also written into the file system. When started, the httpd
* service will be shutdown with the federation.
*/
@Override
public void startService(final Journal indexManager) {
final int httpdPort = Integer.valueOf(indexManager.getProperty(
Options.HTTPD_PORT, Options.DEFAULT_HTTPD_PORT));
if (log.isInfoEnabled())
log.info(Options.HTTPD_PORT + "=" + httpdPort
+ (httpdPort == -1 ? " (disabled)" : ""));
if (httpdPort == -1) {
return;
}
final CounterSetHTTPD httpd;
try {
httpd = new CounterSetHTTPD(httpdPort, indexManager);
} catch (IOException e) {
log.error("Could not start httpd: port=" + httpdPort, e);
return;
}
final String httpdURL;
try {
httpdURL = "http://"
+ AbstractStatisticsCollector.fullyQualifiedHostName + ":"
+ httpd.getPort() + "/?path="
+ URLEncoder.encode("", "UTF-8");
} catch (UnsupportedEncodingException ex) {
log.error("Could not start httpd: " + ex, ex);
httpd.shutdownNow();
return;
}
synchronized (this) {
// save reference to the daemon.
this.httpd = httpd;
// the URL that may be used to access the local httpd.
this.httpdURL = httpdURL;
if (log.isInfoEnabled())
log.info("Performance counters: " + httpdURL);
}
}
@Override
public void stopService(final boolean immediateShutdown) {
synchronized (this) {
if (httpd != null) {
httpd.shutdown();
httpd = null;
httpdURL = null;
}
}
}
@Override
public CounterSetHTTPD getService() {
synchronized (this) {
return httpd;
}
}
@Override
public boolean isRunning() {
synchronized (this) {
return httpd != null;
}
}
/**
* The URL that may be used to access the httpd service exposed by this
* client -or- <code>null</code> if not enabled.
*/
final public String getHttpdURL() {
synchronized (this) {
return httpdURL;
}
}
}