/**
    *
    * 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.mapreduce;
  
  import org.apache.hadoop.hbase.classification.InterfaceAudience;
  import org.apache.hadoop.hbase.classification.InterfaceStability;
  
  import java.io.IOException;
  import java.util.HashMap;
  import java.util.Map;
  import java.util.Random;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.apache.hadoop.conf.Configuration;
  import org.apache.hadoop.conf.Configured;
  import org.apache.hadoop.fs.FileSystem;
  import org.apache.hadoop.fs.Path;
  import org.apache.hadoop.hbase.HBaseConfiguration;
  import org.apache.hadoop.hbase.HConstants;
  import org.apache.hadoop.hbase.TableName;
  import org.apache.hadoop.hbase.client.Connection;
  import org.apache.hadoop.hbase.client.ConnectionFactory;
  import org.apache.hadoop.hbase.client.Scan;
  import org.apache.hadoop.hbase.client.Table;
  import org.apache.hadoop.hbase.util.Bytes;
  import org.apache.hadoop.hbase.util.FSUtils;
  import org.apache.hadoop.mapreduce.Job;
  import org.apache.hadoop.util.GenericOptionsParser;
  import org.apache.hadoop.util.Tool;
  import org.apache.hadoop.util.ToolRunner;
  
  /**
   * Tool used to copy a table to another one which can be on a different setup.
   * It is also configurable with a start and time as well as a specification
   * of the region server implementation if different from the local cluster.
   */
  @InterfaceAudience.Public
  @InterfaceStability.Stable
  public class CopyTable extends Configured implements Tool {
    private static final Log LOG = LogFactory.getLog(CopyTable.class);
  
    final static String NAME = "copytable";
    long startTime = 0;
    long endTime = 0;
    int versions = -1;
    String tableName = null;
    String startRow = null;
    String stopRow = null;
    String dstTableName = null;
    String peerAddress = null;
    String families = null;
    boolean allCells = false;
    static boolean shuffle = false;
  
    boolean bulkload = false;
    Path bulkloadDir = null;
  
    private final static String JOB_NAME_CONF_KEY = "mapreduce.job.name";
  
    public CopyTable(Configuration conf) {
      super(conf);
    }
    /**
     * Sets up the actual job.
     *
     * @param args  The command line parameters.
     * @return The newly created job.
     * @throws IOException When setting up the job fails.
     */
    public Job createSubmittableJob(String[] args)
    throws IOException {
      if (!doCommandLine(args)) {
        return null;
      }
  
      Job job = Job.getInstance(getConf(), getConf().get(JOB_NAME_CONF_KEY, NAME + "_" + tableName));
  
      job.setJarByClass(CopyTable.class);
      Scan scan = new Scan();
      scan.setCacheBlocks(false);
      if (startTime != 0) {
        scan.setTimeRange(startTime,
           endTime == 0 ? HConstants.LATEST_TIMESTAMP : endTime);
     }
     if (allCells) {
       scan.setRaw(true);
     }
     if (shuffle) {
       job.getConfiguration().set(TableInputFormat.SHUFFLE_MAPS, "true");
     }
     if (versions >= 0) {
       scan.setMaxVersions(versions);
     }
 
     if (startRow != null) {
       scan.setStartRow(Bytes.toBytes(startRow));
     }
 
     if (stopRow != null) {
       scan.setStopRow(Bytes.toBytes(stopRow));
     }
 
     if(families != null) {
       String[] fams = families.split(",");
       Map<String,String> cfRenameMap = new HashMap<String,String>();
       for(String fam : fams) {
         String sourceCf;
         if(fam.contains(":")) {
             // fam looks like "sourceCfName:destCfName"
             String[] srcAndDest = fam.split(":", 2);
             sourceCf = srcAndDest[0];
             String destCf = srcAndDest[1];
             cfRenameMap.put(sourceCf, destCf);
         } else {
             // fam is just "sourceCf"
             sourceCf = fam;
         }
         scan.addFamily(Bytes.toBytes(sourceCf));
       }
       Import.configureCfRenaming(job.getConfiguration(), cfRenameMap);
     }
     job.setNumReduceTasks(0);
 
     if (bulkload) {
       TableMapReduceUtil.initTableMapperJob(tableName, scan, Import.KeyValueImporter.class, null,
         null, job);
 
       // We need to split the inputs by destination tables so that output of Map can be bulk-loaded.
       TableInputFormat.configureSplitTable(job, TableName.valueOf(dstTableName));
 
       FileSystem fs = FSUtils.getCurrentFileSystem(getConf());
       Random rand = new Random();
       Path root = new Path(fs.getWorkingDirectory(), "copytable");
       fs.mkdirs(root);
       while (true) {
         bulkloadDir = new Path(root, "" + rand.nextLong());
         if (!fs.exists(bulkloadDir)) {
           break;
         }
       }
 
       System.out.println("HFiles will be stored at " + this.bulkloadDir);
       HFileOutputFormat2.setOutputPath(job, bulkloadDir);
       try (Connection conn = ConnectionFactory.createConnection(getConf());
           Table htable = conn.getTable(TableName.valueOf(dstTableName))) {
         HFileOutputFormat2.configureIncrementalLoadMap(job, htable);
       }
     } else {
       TableMapReduceUtil.initTableMapperJob(tableName, scan,
         Import.Importer.class, null, null, job);
 
       TableMapReduceUtil.initTableReducerJob(dstTableName, null, job, null, peerAddress, null,
         null);
     }
 
     return job;
   }
 
   /*
    * @param errorMsg Error message.  Can be null.
    */
   private static void printUsage(final String errorMsg) {
     if (errorMsg != null && errorMsg.length() > 0) {
       System.err.println("ERROR: " + errorMsg);
     }
     System.err.println("Usage: CopyTable [general options] [--starttime=X] [--endtime=Y] " +
         "[--new.name=NEW] [--peer.adr=ADR] <tablename>");
     System.err.println();
     System.err.println("Options:");
     System.err.println(" rs.class     hbase.regionserver.class of the peer cluster");
     System.err.println("              specify if different from current cluster");
     System.err.println(" rs.impl      hbase.regionserver.impl of the peer cluster");
     System.err.println(" startrow     the start row");
     System.err.println(" stoprow      the stop row");
     System.err.println(" starttime    beginning of the time range (unixtime in millis)");
     System.err.println("              without endtime means from starttime to forever");
     System.err.println(" endtime      end of the time range.  Ignored if no starttime specified.");
     System.err.println(" versions     number of cell versions to copy");
     System.err.println(" new.name     new table's name");
     System.err.println(" peer.adr     Address of the peer cluster given in the format");
     System.err.println("              hbase.zookeeer.quorum:hbase.zookeeper.client.port:zookeeper.znode.parent");
     System.err.println(" families     comma-separated list of families to copy");
     System.err.println("              To copy from cf1 to cf2, give sourceCfName:destCfName. ");
     System.err.println("              To keep the same name, just give \"cfName\"");
     System.err.println(" all.cells    also copy delete markers and deleted cells");
     System.err.println(" bulkload     Write input into HFiles and bulk load to the destination "
         + "table");
     System.err.println();
     System.err.println("Args:");
     System.err.println(" tablename    Name of the table to copy");
     System.err.println();
     System.err.println("Examples:");
     System.err.println(" To copy 'TestTable' to a cluster that uses replication for a 1 hour window:");
     System.err.println(" $ bin/hbase " +
         "org.apache.hadoop.hbase.mapreduce.CopyTable --starttime=1265875194289 --endtime=1265878794289 " +
         "--peer.adr=server1,server2,server3:2181:/hbase --families=myOldCf:myNewCf,cf2,cf3 TestTable ");
     System.err.println("For performance consider the following general option:\n"
         + "  It is recommended that you set the following to >=100. A higher value uses more memory but\n"
         + "  decreases the round trip time to the server and may increase performance.\n"
         + "    -Dhbase.client.scanner.caching=100\n"
         + "  The following should always be set to false, to prevent writing data twice, which may produce \n"
         + "  inaccurate results.\n"
         + "    -Dmapreduce.map.speculative=false");
   }
 
   private boolean doCommandLine(final String[] args) {
     // Process command-line args. TODO: Better cmd-line processing
     // (but hopefully something not as painful as cli options).
     if (args.length < 1) {
       printUsage(null);
       return false;
     }
     try {
       for (int i = 0; i < args.length; i++) {
         String cmd = args[i];
         if (cmd.equals("-h") || cmd.startsWith("--h")) {
           printUsage(null);
           return false;
         }
 
         final String startRowArgKey = "--startrow=";
         if (cmd.startsWith(startRowArgKey)) {
           startRow = cmd.substring(startRowArgKey.length());
           continue;
         }
 
         final String stopRowArgKey = "--stoprow=";
         if (cmd.startsWith(stopRowArgKey)) {
           stopRow = cmd.substring(stopRowArgKey.length());
           continue;
         }
 
         final String startTimeArgKey = "--starttime=";
         if (cmd.startsWith(startTimeArgKey)) {
           startTime = Long.parseLong(cmd.substring(startTimeArgKey.length()));
           continue;
         }
 
         final String endTimeArgKey = "--endtime=";
         if (cmd.startsWith(endTimeArgKey)) {
           endTime = Long.parseLong(cmd.substring(endTimeArgKey.length()));
           continue;
         }
 
         final String versionsArgKey = "--versions=";
         if (cmd.startsWith(versionsArgKey)) {
           versions = Integer.parseInt(cmd.substring(versionsArgKey.length()));
           continue;
         }
 
         final String newNameArgKey = "--new.name=";
         if (cmd.startsWith(newNameArgKey)) {
           dstTableName = cmd.substring(newNameArgKey.length());
           continue;
         }
 
         final String peerAdrArgKey = "--peer.adr=";
         if (cmd.startsWith(peerAdrArgKey)) {
           peerAddress = cmd.substring(peerAdrArgKey.length());
           continue;
         }
 
         final String familiesArgKey = "--families=";
         if (cmd.startsWith(familiesArgKey)) {
           families = cmd.substring(familiesArgKey.length());
           continue;
         }
 
         if (cmd.startsWith("--all.cells")) {
           allCells = true;
           continue;
         }
 
         if (cmd.startsWith("--bulkload")) {
           bulkload = true;
           continue;
         }
 
         if (cmd.startsWith("--shuffle")) {
           shuffle = true;
           continue;
         }
 
         if (i == args.length-1) {
           tableName = cmd;
         } else {
           printUsage("Invalid argument '" + cmd + "'" );
           return false;
         }
       }
       if (dstTableName == null && peerAddress == null) {
         printUsage("At least a new table name or a " +
             "peer address must be specified");
         return false;
       }
       if ((endTime != 0) && (startTime > endTime)) {
         printUsage("Invalid time range filter: starttime=" + startTime + " >  endtime=" + endTime);
         return false;
       }
 
       if (bulkload && peerAddress != null) {
         printUsage("Remote bulkload is not supported!");
         return false;
       }
 
       // set dstTableName if necessary
       if (dstTableName == null) {
         dstTableName = tableName;
       }
     } catch (Exception e) {
       e.printStackTrace();
       printUsage("Can't start because " + e.getMessage());
       return false;
     }
     return true;
   }
 
   /**
    * Main entry point.
    *
    * @param args  The command line parameters.
    * @throws Exception When running the job fails.
    */
   public static void main(String[] args) throws Exception {
     int ret = ToolRunner.run(new CopyTable(HBaseConfiguration.create()), args);
     System.exit(ret);
   }
 
   @Override
   public int run(String[] args) throws Exception {
     String[] otherArgs = new GenericOptionsParser(getConf(), args).getRemainingArgs();
     Job job = createSubmittableJob(otherArgs);
     if (job == null) return 1;
     if (!job.waitForCompletion(true)) {
       LOG.info("Map-reduce job failed!");
       if (bulkload) {
         LOG.info("Files are not bulkloaded!");
       }
       return 1;
     }
     int code = 0;
     if (bulkload) {
       code = new LoadIncrementalHFiles(this.getConf()).run(new String[]{this.bulkloadDir.toString(),
           this.dstTableName});
       if (code == 0) {
         // bulkloadDir is deleted only LoadIncrementalHFiles was successful so that one can rerun
         // LoadIncrementalHFiles.
         FileSystem fs = FSUtils.getCurrentFileSystem(getConf());
         if (!fs.delete(this.bulkloadDir, true)) {
           LOG.error("Deleting folder " + bulkloadDir + " failed!");
           code = 1;
         }
       }
     }
     return code;
   }
 }