/*
    * 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.util;
  
  import java.io.BufferedReader;
  import java.io.BufferedWriter;
  import java.io.File;
  import java.io.FileInputStream;
  import java.io.FileNotFoundException;
  import java.io.FileWriter;
  import java.io.FilenameFilter;
  import java.io.IOException;
  import java.io.InputStreamReader;
  import java.io.PrintStream;
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.HashSet;
  import java.util.List;
  import java.util.Map;
  import java.util.Scanner;
  import java.util.Set;
  import java.util.TreeMap;
  import java.util.regex.Matcher;
  import java.util.regex.Pattern;
  
  import org.apache.commons.io.FileUtils;
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.apache.hadoop.conf.Configuration;
  import org.apache.hadoop.hbase.HBaseTestingUtility;
  import org.apache.hadoop.hbase.HConstants;
  import org.apache.hadoop.hbase.testclassification.LargeTests;
  import org.apache.hadoop.hbase.MiniHBaseCluster;
  import org.apache.hadoop.hbase.TableName;
  import org.apache.hadoop.hbase.client.HTable;
  import org.apache.hadoop.hbase.zookeeper.ZKUtil;
  import org.apache.hadoop.hdfs.MiniDFSCluster;
  import org.junit.experimental.categories.Category;
  
  /**
   * A helper class for process-based mini-cluster tests. Unlike
   * {@link MiniHBaseCluster}, starts daemons as separate processes, allowing to
   * do real kill testing.
   */
  @Category(LargeTests.class)
  public class ProcessBasedLocalHBaseCluster {
  
    private final String hbaseHome, workDir;
    private final Configuration conf;
    private final int numMasters, numRegionServers, numDataNodes;
    private final List<Integer> rsPorts, masterPorts;
  
    private final int zkClientPort;
  
    private static final int MAX_FILE_SIZE_OVERRIDE = 10 * 1000 * 1000;
  
    private static final Log LOG = LogFactory.getLog(
        ProcessBasedLocalHBaseCluster.class);
  
    private List<String> daemonPidFiles =
        Collections.synchronizedList(new ArrayList<String>());;
  
    private boolean shutdownHookInstalled;
  
    private String hbaseDaemonScript;
  
    private MiniDFSCluster dfsCluster;
  
    private HBaseTestingUtility testUtil;
  
    private Thread logTailerThread;
  
    private List<String> logTailDirs = Collections.synchronizedList(new ArrayList<String>());
  
    private static enum ServerType {
      MASTER("master"),
      RS("regionserver"),
      ZK("zookeeper");
  
      private final String fullName;
  
      private ServerType(String fullName) {
        this.fullName = fullName;
      }
   }
 
   /**
    * Constructor. Modifies the passed configuration.
    * @param conf the {@link Configuration} to use
    * @param numDataNodes the number of data nodes
    * @param numRegionServers the number of region servers
    */
   public ProcessBasedLocalHBaseCluster(Configuration conf,
       int numDataNodes, int numRegionServers) {
     this.conf = conf;
     this.hbaseHome = HBaseHomePath.getHomePath();
     this.numMasters = 1;
     this.numRegionServers = numRegionServers;
     this.workDir = hbaseHome + "/target/local_cluster";
     this.numDataNodes = numDataNodes;
 
     hbaseDaemonScript = hbaseHome + "/bin/hbase-daemon.sh";
     zkClientPort = HBaseTestingUtility.randomFreePort();
 
     this.rsPorts = sortedPorts(numRegionServers);
     this.masterPorts = sortedPorts(numMasters);
 
     conf.set(HConstants.ZOOKEEPER_QUORUM, HConstants.LOCALHOST);
     conf.setInt(HConstants.ZOOKEEPER_CLIENT_PORT, zkClientPort);
   }
 
   /**
    * Makes this local HBase cluster use a mini-DFS cluster. Must be called before
    * {@link #startHBase()}.
    * @throws IOException
    */
   public void startMiniDFS() throws Exception {
     if (testUtil == null) {
       testUtil = new HBaseTestingUtility(conf);
     }
     dfsCluster = testUtil.startMiniDFSCluster(numDataNodes);
   }
 
   /**
    * Generates a list of random port numbers in the sorted order. A sorted
    * order makes sense if we ever want to refer to these servers by their index
    * in the returned array, e.g. server #0, #1, etc.
    */
   private static List<Integer> sortedPorts(int n) {
     List<Integer> ports = new ArrayList<Integer>(n);
     for (int i = 0; i < n; ++i) {
       ports.add(HBaseTestingUtility.randomFreePort());
     }
     Collections.sort(ports);
     return ports;
   }
 
   public void startHBase() throws IOException {
     startDaemonLogTailer();
     cleanupOldState();
 
     // start ZK
     LOG.info("Starting ZooKeeper on port " + zkClientPort);
     startZK();
 
     HBaseTestingUtility.waitForHostPort(HConstants.LOCALHOST, zkClientPort);
 
     for (int masterPort : masterPorts) {
       startMaster(masterPort);
     }
 
     ZKUtil.waitForBaseZNode(conf);
 
     for (int rsPort : rsPorts) {
       startRegionServer(rsPort);
     }
 
     LOG.info("Waiting for HBase startup by scanning META");
     int attemptsLeft = 10;
     while (attemptsLeft-- > 0) {
       try {
         new HTable(conf, TableName.META_TABLE_NAME);
       } catch (Exception e) {
         LOG.info("Waiting for HBase to startup. Retries left: " + attemptsLeft,
             e);
         Threads.sleep(1000);
       }
     }
 
     LOG.info("Process-based HBase Cluster with " + numRegionServers +
         " region servers up and running... \n\n");
   }
 
   public void startRegionServer(int port) {
     startServer(ServerType.RS, port);
   }
 
   public void startMaster(int port) {
     startServer(ServerType.MASTER, port);
   }
 
   public void killRegionServer(int port) throws IOException {
     killServer(ServerType.RS, port);
   }
 
   public void killMaster() throws IOException {
     killServer(ServerType.MASTER, 0);
   }
 
   public void startZK() {
     startServer(ServerType.ZK, 0);
   }
 
   private void executeCommand(String command) {
     executeCommand(command, null);
   }
 
   private void executeCommand(String command, Map<String,
       String> envOverrides) {
     ensureShutdownHookInstalled();
     LOG.debug("Command : " + command);
 
     try {
       String [] envp = null;
       if (envOverrides != null) {
         Map<String, String> map = new HashMap<String, String>(
             System.getenv());
         map.putAll(envOverrides);
         envp = new String[map.size()];
         int idx = 0;
         for (Map.Entry<String, String> e: map.entrySet()) {
           envp[idx++] = e.getKey() + "=" + e.getValue();
         }
       }
 
       Process p = Runtime.getRuntime().exec(command, envp);
 
       BufferedReader stdInput = new BufferedReader(
           new InputStreamReader(p.getInputStream()));
       BufferedReader stdError = new BufferedReader(
           new InputStreamReader(p.getErrorStream()));
 
       // read the output from the command
       String s = null;
       while ((s = stdInput.readLine()) != null) {
         System.out.println(s);
       }
 
       // read any errors from the attempted command
       while ((s = stdError.readLine()) != null) {
         System.out.println(s);
       }
     } catch (IOException e) {
       LOG.error("Error running: " + command, e);
     }
   }
 
   private void shutdownAllProcesses() {
     LOG.info("Killing daemons using pid files");
     final List<String> pidFiles = new ArrayList<String>(daemonPidFiles);
     for (String pidFile : pidFiles) {
       int pid = 0;
       try {
         pid = readPidFromFile(pidFile);
       } catch (IOException ex) {
         LOG.error("Could not read pid from file " + pidFile);
       }
 
       if (pid > 0) {
         LOG.info("Killing pid " + pid + " (" + pidFile + ")");
         killProcess(pid);
       }
     }
   }
 
   private void ensureShutdownHookInstalled() {
     if (shutdownHookInstalled) {
       return;
     }
 
     Runtime.getRuntime().addShutdownHook(new Thread(new Runnable() {
       @Override
       public void run() {
         shutdownAllProcesses();
       }
     }));
 
     shutdownHookInstalled = true;
   }
 
   private void cleanupOldState() {
     executeCommand("rm -rf " + workDir);
   }
 
   private void writeStringToFile(String s, String fileName) {
     try {
       BufferedWriter out = new BufferedWriter(new FileWriter(fileName));
       out.write(s);
       out.close();
     } catch (IOException e) {
       LOG.error("Error writing to: " + fileName, e);
     }
   }
 
   private String serverWorkingDir(ServerType serverType, int port) {
     return workDir + "/" + serverType + "-" + port;
   }
 
   private int getServerPID(ServerType serverType, int port) throws IOException {
     String pidFile = pidFilePath(serverType, port);
     return readPidFromFile(pidFile);
   }
 
   private static int readPidFromFile(String pidFile) throws IOException {
     Scanner scanner = new Scanner(new File(pidFile));
     try {
       return scanner.nextInt();
     } finally {
       scanner.close();
     }
   }
 
   private String pidFilePath(ServerType serverType, int port) {
     String dir = serverWorkingDir(serverType, port);
     String user = System.getenv("USER");
     String pidFile = String.format("%s/hbase-%s-%s.pid",
                                    dir, user, serverType.fullName);
     return pidFile;
   }
 
   private void killServer(ServerType serverType, int port) throws IOException {
     int pid = getServerPID(serverType, port);
     if (pid > 0) {
       LOG.info("Killing " + serverType + "; pid=" + pid);
       killProcess(pid);
     }
   }
 
   private void killProcess(int pid) {
     String cmd = "kill -s KILL " + pid;
     executeCommand(cmd);
   }
 
   private void startServer(ServerType serverType, int rsPort) {
     // create working directory for this region server.
     String dir = serverWorkingDir(serverType, rsPort);
     String confStr = generateConfig(serverType, rsPort, dir);
     LOG.debug("Creating directory " + dir);
     new File(dir).mkdirs();
 
     writeStringToFile(confStr, dir + "/hbase-site.xml");
 
     // Set debug options to an empty string so that hbase-config.sh does not configure them
     // using default ports. If we want to run remote debugging on process-based local cluster's
     // daemons, we can automatically choose non-conflicting JDWP and JMX ports for each daemon
     // and specify them here.
     writeStringToFile(
         "unset HBASE_MASTER_OPTS\n" +
         "unset HBASE_REGIONSERVER_OPTS\n" +
         "unset HBASE_ZOOKEEPER_OPTS\n" +
         "HBASE_MASTER_DBG_OPTS=' '\n" +
         "HBASE_REGIONSERVER_DBG_OPTS=' '\n" +
         "HBASE_ZOOKEEPER_DBG_OPTS=' '\n" +
         "HBASE_MASTER_JMX_OPTS=' '\n" +
         "HBASE_REGIONSERVER_JMX_OPTS=' '\n" +
         "HBASE_ZOOKEEPER_JMX_OPTS=' '\n",
         dir + "/hbase-env.sh");
 
     Map<String, String> envOverrides = new HashMap<String, String>();
     envOverrides.put("HBASE_LOG_DIR", dir);
     envOverrides.put("HBASE_PID_DIR", dir);
     try {
       FileUtils.copyFile(
           new File(hbaseHome, "conf/log4j.properties"),
           new File(dir, "log4j.properties"));
     } catch (IOException ex) {
       LOG.error("Could not install log4j.properties into " + dir);
     }
 
     executeCommand(hbaseDaemonScript + " --config " + dir +
                    " start " + serverType.fullName, envOverrides);
     daemonPidFiles.add(pidFilePath(serverType, rsPort));
     logTailDirs.add(dir);
   }
 
   private final String generateConfig(ServerType serverType, int rpcPort,
       String daemonDir) {
     StringBuilder sb = new StringBuilder();
     Map<String, Object> confMap = new TreeMap<String, Object>();
     confMap.put(HConstants.CLUSTER_DISTRIBUTED, true);
 
     if (serverType == ServerType.MASTER) {
       confMap.put(HConstants.MASTER_PORT, rpcPort);
 
       int masterInfoPort = HBaseTestingUtility.randomFreePort();
       reportWebUIPort("master", masterInfoPort);
       confMap.put(HConstants.MASTER_INFO_PORT, masterInfoPort);
     } else if (serverType == ServerType.RS) {
       confMap.put(HConstants.REGIONSERVER_PORT, rpcPort);
 
       int rsInfoPort = HBaseTestingUtility.randomFreePort();
       reportWebUIPort("region server", rsInfoPort);
       confMap.put(HConstants.REGIONSERVER_INFO_PORT, rsInfoPort);
     } else {
       confMap.put(HConstants.ZOOKEEPER_DATA_DIR, daemonDir);
     }
 
     confMap.put(HConstants.ZOOKEEPER_CLIENT_PORT, zkClientPort);
     confMap.put(HConstants.HREGION_MAX_FILESIZE, MAX_FILE_SIZE_OVERRIDE);
 
     if (dfsCluster != null) {
       String fsURL = "hdfs://" + HConstants.LOCALHOST + ":" + dfsCluster.getNameNodePort();
       confMap.put("fs.defaultFS", fsURL);
       confMap.put("hbase.rootdir", fsURL + "/hbase_test");
     }
 
     sb.append("<configuration>\n");
     for (Map.Entry<String, Object> entry : confMap.entrySet()) {
       sb.append("  <property>\n");
       sb.append("    <name>" + entry.getKey() + "</name>\n");
       sb.append("    <value>" + entry.getValue() + "</value>\n");
       sb.append("  </property>\n");
     }
     sb.append("</configuration>\n");
     return sb.toString();
   }
 
   private static void reportWebUIPort(String daemon, int port) {
     LOG.info("Local " + daemon + " web UI is at http://"
         + HConstants.LOCALHOST + ":" + port);
   }
 
   public Configuration getConf() {
     return conf;
   }
 
   public void shutdown() {
     if (dfsCluster != null) {
       dfsCluster.shutdown();
     }
     shutdownAllProcesses();
   }
 
   private static final Pattern TO_REMOVE_FROM_LOG_LINES_RE =
       Pattern.compile("org\\.apache\\.hadoop\\.hbase\\.");
 
   private static final Pattern LOG_PATH_FORMAT_RE =
       Pattern.compile("^.*/([A-Z]+)-(\\d+)/[^/]+$");
 
   private static String processLine(String line) {
     Matcher m = TO_REMOVE_FROM_LOG_LINES_RE.matcher(line);
     return m.replaceAll("");
   }
 
   private final class LocalDaemonLogTailer implements Runnable {
     private final Set<String> tailedFiles = new HashSet<String>();
     private final List<String> dirList = new ArrayList<String>();
     private final Object printLock = new Object();
 
     private final FilenameFilter LOG_FILES = new FilenameFilter() {
       @Override
       public boolean accept(File dir, String name) {
         return name.endsWith(".out") || name.endsWith(".log");
       }
     };
 
     @Override
     public void run() {
       try {
         runInternal();
       } catch (IOException ex) {
         LOG.error(ex);
       }
     }
 
     private void runInternal() throws IOException {
       Thread.currentThread().setName(getClass().getSimpleName());
       while (true) {
         scanDirs();
         try {
           Thread.sleep(500);
         } catch (InterruptedException e) {
           LOG.error("Log tailer thread interrupted", e);
           break;
         }
       }
     }
 
     private void scanDirs() throws FileNotFoundException {
       dirList.clear();
       dirList.addAll(logTailDirs);
       for (String d : dirList) {
         File[] files = new File(d).listFiles(LOG_FILES);
         if (files != null) {
           for (File f : files) {
             String filePath = f.getAbsolutePath();
             if (!tailedFiles.contains(filePath)) {
               tailedFiles.add(filePath);
               startTailingFile(filePath);
             }
           }
         }
       }
     }
 
     private void startTailingFile(final String filePath) throws FileNotFoundException {
       final PrintStream dest = filePath.endsWith(".log") ? System.err : System.out;
       final ServerType serverType;
       final int serverPort;
       Matcher m = LOG_PATH_FORMAT_RE.matcher(filePath);
       if (m.matches()) {
         serverType = ServerType.valueOf(m.group(1));
         serverPort = Integer.valueOf(m.group(2));
       } else {
         LOG.error("Unrecognized log path format: " + filePath);
         return;
       }
       final String logMsgPrefix =
           "[" + serverType + (serverPort != 0 ? ":" + serverPort : "") + "] ";
 
       LOG.debug("Tailing " + filePath);
       Thread t = new Thread(new Runnable() {
         @Override
         public void run() {
           try {
             FileInputStream fis = new FileInputStream(filePath);
             BufferedReader br = new BufferedReader(new InputStreamReader(fis));
             String line;
             while (true) {
               try {
                 Thread.sleep(200);
               } catch (InterruptedException e) {
                 LOG.error("Tailer for " + filePath + " interrupted");
                 break;
               }
               while ((line = br.readLine()) != null) {
                 line = logMsgPrefix + processLine(line);
                 synchronized (printLock) {
                   if (line.endsWith("\n")) {
                     dest.print(line);
                   } else {
                     dest.println(line);
                   }
                   dest.flush();
                 }
               }
             }
           } catch (IOException ex) {
             LOG.error("Failed tailing " + filePath, ex);
           }
         }
       });
       t.setDaemon(true);
       t.setName("Tailer for " + filePath);
       t.start();
     }
 
   }
 
   private void startDaemonLogTailer() {
     logTailerThread = new Thread(new LocalDaemonLogTailer());
     logTailerThread.setDaemon(true);
     logTailerThread.start();
   }
 
 }