001/* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, software 013 * distributed under the License is distributed on an "AS IS" BASIS, 014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 015 * See the License for the specific language governing permissions and 016 * limitations under the License. 017 */ 018package org.apache.hadoop.hbase.master.http; 019 020import java.io.IOException; 021import java.util.List; 022import java.util.Map; 023import java.util.Set; 024import javax.servlet.http.HttpServlet; 025import javax.servlet.http.HttpServletRequest; 026import javax.servlet.http.HttpServletResponse; 027import org.apache.hadoop.conf.Configuration; 028import org.apache.hadoop.hbase.ServerName; 029import org.apache.hadoop.hbase.client.RegionInfoBuilder; 030import org.apache.hadoop.hbase.master.HMaster; 031import org.apache.hadoop.hbase.master.RegionState; 032import org.apache.hadoop.hbase.master.ServerManager; 033import org.apache.hadoop.hbase.master.assignment.RegionStateNode; 034import org.apache.hadoop.hbase.tmpl.master.MasterStatusTmpl; 035import org.apache.hadoop.hbase.util.FSUtils; 036import org.apache.yetus.audience.InterfaceAudience; 037 038/** 039 * The servlet responsible for rendering the index page of the master. 040 */ 041@InterfaceAudience.Private 042public class MasterStatusServlet extends HttpServlet { 043 private static final long serialVersionUID = 1L; 044 045 @Override 046 public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException { 047 HMaster master = (HMaster) getServletContext().getAttribute(HMaster.MASTER); 048 assert master != null : "No Master in context!"; 049 050 response.setContentType("text/html"); 051 052 Configuration conf = master.getConfiguration(); 053 054 Map<String, Integer> frags = getFragmentationInfo(master, conf); 055 ServerName metaLocation = null; 056 List<ServerName> servers = null; 057 Set<ServerName> deadServers = null; 058 059 if (master.isActiveMaster()) { 060 metaLocation = getMetaLocationOrNull(master); 061 ServerManager serverManager = master.getServerManager(); 062 if (serverManager != null) { 063 deadServers = serverManager.getDeadServers().copyServerNames(); 064 servers = serverManager.getOnlineServersList(); 065 } 066 } 067 068 MasterStatusTmpl tmpl = 069 new MasterStatusTmpl().setFrags(frags).setMetaLocation(metaLocation).setServers(servers) 070 .setDeadServers(deadServers).setCatalogJanitorEnabled(master.isCatalogJanitorEnabled()); 071 072 if (request.getParameter("filter") != null) tmpl.setFilter(request.getParameter("filter")); 073 if (request.getParameter("format") != null) tmpl.setFormat(request.getParameter("format")); 074 tmpl.render(response.getWriter(), master); 075 } 076 077 private ServerName getMetaLocationOrNull(HMaster master) { 078 RegionStateNode rsn = master.getAssignmentManager().getRegionStates() 079 .getRegionStateNode(RegionInfoBuilder.FIRST_META_REGIONINFO); 080 if (rsn != null) { 081 return rsn.isInState(RegionState.State.OPEN) ? rsn.getRegionLocation() : null; 082 } 083 return null; 084 } 085 086 private Map<String, Integer> getFragmentationInfo(HMaster master, Configuration conf) 087 throws IOException { 088 boolean showFragmentation = conf.getBoolean("hbase.master.ui.fragmentation.enabled", false); 089 if (showFragmentation) { 090 return FSUtils.getTableFragmentation(master); 091 } else { 092 return null; 093 } 094 } 095}