/**
*
* 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.hadoop.hbase.master;
import java.io.IOException;
import java.util.List;
import java.util.Map;
import java.util.Set;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.ServerName;
import org.apache.hadoop.hbase.client.HBaseAdmin;
import org.apache.hadoop.hbase.tmpl.master.MasterStatusTmpl;
import org.apache.hadoop.hbase.util.FSUtils;
import org.apache.hadoop.hbase.zookeeper.MetaTableLocator;
/**
* The servlet responsible for rendering the index page of the
* master.
*/
@InterfaceAudience.Private
public class MasterStatusServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
@Override
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws IOException
{
HMaster master = (HMaster) getServletContext().getAttribute(HMaster.MASTER);
assert master != null : "No Master in context!";
response.setContentType("text/html");
Configuration conf = master.getConfiguration();
HBaseAdmin admin = new HBaseAdmin(conf);
Map<String, Integer> frags = getFragmentationInfo(master, conf);
ServerName metaLocation = null;
List<ServerName> servers = null;
Set<ServerName> deadServers = null;
if(master.isActiveMaster()) {
metaLocation = getMetaLocationOrNull(master);
ServerManager serverManager = master.getServerManager();
if (serverManager != null) {
deadServers = serverManager.getDeadServers().copyServerNames();
servers = serverManager.getOnlineServersList();
}
}
MasterStatusTmpl tmpl = new MasterStatusTmpl()
.setFrags(frags)
.setMetaLocation(metaLocation)
.setServers(servers)
.setDeadServers(deadServers)
.setCatalogJanitorEnabled(master.isCatalogJanitorEnabled());
if (request.getParameter("filter") != null)
tmpl.setFilter(request.getParameter("filter"));
if (request.getParameter("format") != null)
tmpl.setFormat(request.getParameter("format"));
tmpl.render(response.getWriter(),
master, admin);
}
private ServerName getMetaLocationOrNull(HMaster master) {
MetaTableLocator metaTableLocator = master.getMetaTableLocator();
return metaTableLocator == null ? null :
metaTableLocator.getMetaRegionLocation(master.getZooKeeper());
}
private Map<String, Integer> getFragmentationInfo(
HMaster master, Configuration conf) throws IOException {
boolean showFragmentation = conf.getBoolean(
"hbase.master.ui.fragmentation.enabled", false);
if (showFragmentation) {
return FSUtils.getTableFragmentation(master);
} else {
return null;
}
}
}