content: /**
   *
   * 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 com.alibaba.wasp.fserver;
  
  import com.alibaba.wasp.monitoring.StateDumpServlet;
  import org.apache.hadoop.classification.InterfaceAudience;
  import org.apache.hadoop.conf.Configuration;
  import org.apache.hadoop.hbase.monitoring.LogMonitoring;
  import org.apache.hadoop.hbase.monitoring.TaskMonitor;
  import org.apache.hadoop.util.ReflectionUtils;
  
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  import java.io.IOException;
  import java.io.OutputStream;
  import java.io.PrintWriter;
  import java.util.Date;
  
  @InterfaceAudience.Private
  public class FSDumpServlet extends StateDumpServlet {
    private static final long serialVersionUID = 1L;
    private static final String LINE =
      "===========================================================";
    
    @Override
    public void doGet(HttpServletRequest request, HttpServletResponse response)
        throws IOException {
      FServer fs = (FServer)getServletContext().getAttribute(
          FServer.FSERVER);
      assert fs != null : "No FS in context!";
      
      Configuration hrsconf = (Configuration)getServletContext().getAttribute(
          FServer.FSERVER_CONF);
      assert hrsconf != null : "No FS conf in context";
  
      response.setContentType("text/plain");
      OutputStream os = response.getOutputStream();
      PrintWriter out = new PrintWriter(os);
      
      out.println("Master status for " + fs.getServerName()
          + " as of " + new Date());
      
      out.println("\n\nVersion Info:");
      out.println(LINE);
      dumpVersionInfo(out);
  
      out.println("\n\nTasks:");
      out.println(LINE);
      TaskMonitor.get().dumpAsText(out);
      
      out.println("\n\nExecutors:");
      out.println(LINE);
      dumpExecutors(fs.getExecutorService(), out);
      
      out.println("\n\nStacks:");
      out.println(LINE);
      ReflectionUtils.printThreadInfo(out, "");
      
      out.println("\n\nFS Configuration:");
      out.println(LINE);
      Configuration conf = fs.getConfiguration();
      out.flush();
      conf.writeXml(os);
      os.flush();
      
      out.println("\n\nLogs");
      out.println(LINE);
      long tailKb = getTailKbParam(request);
      LogMonitoring.dumpTailOfLogs(out, tailKb);
      
      out.println("\n\nFS Queue:");
      out.println(LINE);
      if(isShowQueueDump(hrsconf)) {
        dumpQueue(fs, out);
      } 
      
      out.flush();
    }
    
    private boolean isShowQueueDump(Configuration conf){
      return conf.getBoolean("wasp.fserver.servlet.show.queuedump", true);
    }
      
    private void dumpQueue(FServer fs, PrintWriter out)
        throws IOException {
      // 1. Print out Compaction/Split Queue
      out.println("Split Queue summary: "
          + fs.splitThread.toString() );
      out.println(fs.splitThread.dumpQueue());
  
    }
    
  }
  