/**
 * 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.hdfs.server.namenode;

import junit.framework.TestCase;
import org.apache.commons.logging.impl.Log4JLogger;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hdfs.DFSClient;
import org.apache.hadoop.hdfs.DFSTestUtil;
import org.apache.hadoop.hdfs.MiniDFSCluster;
import org.apache.hadoop.hdfs.protocol.CorruptFileBlocks;
import org.apache.hadoop.hdfs.protocol.LocatedBlocks;
import org.apache.hadoop.hdfs.tools.DFSck;
import org.apache.hadoop.io.IOUtils;
import org.apache.hadoop.util.ToolRunner;
import org.apache.log4j.Level;
import org.apache.log4j.Logger;

import javax.servlet.http.HttpServletResponse;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.io.PrintStream;
import java.io.PrintWriter;
import java.io.RandomAccessFile;
import java.net.InetSocketAddress;
import java.nio.channels.FileChannel;
import java.util.HashMap;
import java.util.Map;
import java.util.Random;

/**
 * A JUnit test for doing fsck
 */
public class TestFsck extends TestCase {
  private static final Logger LOG = Logger.getLogger(TestFsck.class);

  static String runFsck(Configuration conf, int expectedErrCode,
                        boolean checkErrorCode, String... path)
    throws Exception {
    ByteArrayOutputStream bStream = new ByteArrayOutputStream();
    PrintStream out = new PrintStream(bStream, true);
    ((Log4JLogger) FSPermissionChecker.LOG).getLogger().setLevel(Level.ALL);
    int errCode = ToolRunner.run(new DFSck(conf, out), path);
    if (checkErrorCode) {
      assertEquals(expectedErrCode, errCode);
    }
    ((Log4JLogger) FSPermissionChecker.LOG).getLogger().setLevel(Level.INFO);
    return bStream.toString();
  }

  /**
   * do fsck
   */
  public void testFsck() throws Exception {
    DFSTestUtil util = new DFSTestUtil("TestFsck", 20, 3, 8 * 1024);
    MiniDFSCluster cluster = null;
    FileSystem fs = null;
    try {
      Configuration conf = new Configuration();
      conf.setLong("dfs.blockreport.intervalMsec", 10000L);
      cluster = new MiniDFSCluster(conf, 4, true, null);
      fs = cluster.getFileSystem();
      util.createFiles(fs, "/srcdat");
      util.waitReplication(fs, "/srcdat", (short) 3);
      String outStr = runFsck(conf, 0, true, "/");
      assertTrue(outStr.contains(NamenodeFsck.HEALTHY_STATUS));
      System.out.println(outStr);
      if (fs != null) {
        try {
          fs.close();
        } catch (Exception e) {
        }
      }
      cluster.shutdown();

      // restart the cluster; bring up namenode but not the data nodes
      cluster = new MiniDFSCluster(conf, 0, false, null);
      outStr = runFsck(conf, 1, true, "/");
      // expect the result is corrupt
      assertTrue(outStr.contains(NamenodeFsck.CORRUPT_STATUS));
      System.out.println(outStr);

      // bring up data nodes & cleanup cluster
      cluster.startDataNodes(conf, 4, true, null, null);
      cluster.waitActive();
      cluster.waitClusterUp();
      fs = cluster.getFileSystem();
      util.cleanup(fs, "/srcdat");
    } finally {
      if (fs != null) {
        try {
          fs.close();
        } catch (Exception e) {
        }
      }
      if (cluster != null) {
        cluster.shutdown();
      }
    }
  }

  public void testFsckNonExistent() throws Exception {
    DFSTestUtil util = new DFSTestUtil("TestFsck", 20, 3, 8 * 1024);
    MiniDFSCluster cluster = null;
    FileSystem fs = null;
    try {
      Configuration conf = new Configuration();
      conf.setLong("dfs.blockreport.intervalMsec", 10000L);
      cluster = new MiniDFSCluster(conf, 4, true, null);
      fs = cluster.getFileSystem();
      util.createFiles(fs, "/srcdat");
      util.waitReplication(fs, "/srcdat", (short) 3);
      String outStr = runFsck(conf, 0, true, "/non-existent");
      assertEquals(-1, outStr.indexOf(NamenodeFsck.HEALTHY_STATUS));
      System.out.println(outStr);
      util.cleanup(fs, "/srcdat");
    } finally {
      if (fs != null) {
        try {
          fs.close();
        } catch (Exception e) {
        }
      }
      if (cluster != null) {
        cluster.shutdown();
      }
    }
  }

  public void testFsckMove() throws Exception {
    DFSTestUtil util = new DFSTestUtil("TestFsck", 5, 3, 8 * 1024);
    MiniDFSCluster cluster = null;
    FileSystem fs = null;
    try {
      Configuration conf = new Configuration();
      conf.setLong("dfs.blockreport.intervalMsec", 10000L);
      cluster = new MiniDFSCluster(conf, 4, true, null);
      String topDir = "/srcdat";
      fs = cluster.getFileSystem();
      cluster.waitActive();
      util.createFiles(fs, topDir);
      util.waitReplication(fs, topDir, (short) 3);
      String outStr = runFsck(conf, 0, true, "/");
      assertTrue(outStr.contains(NamenodeFsck.HEALTHY_STATUS));

      // Corrupt a block by deleting it
      String[] fileNames = util.getFileNames(topDir);
      DFSClient dfsClient = new DFSClient(new InetSocketAddress("localhost",
        cluster.getNameNodePort()), conf);
      String block = dfsClient.namenode.
        getBlockLocations(fileNames[0], 0, Long.MAX_VALUE).
        get(0).getBlock().getBlockName();
      for (int i = 0; i < 8; i++) {
        File blockFile = new File(cluster.getBlockDirectory("data" + (i + 1)), block);
        if (blockFile.exists()) {
          assertTrue(blockFile.delete());
        }
      }

      // We excpect the filesystem to be corrupted
      outStr = runFsck(conf, 1, false, "/");
      while (!outStr.contains(NamenodeFsck.CORRUPT_STATUS)) {
        try {
          Thread.sleep(100);
        } catch (InterruptedException ignore) {
        }
        outStr = runFsck(conf, 1, false, "/");
      }

      // Fix the filesystem by moving corrupted files to lost+found
      outStr = runFsck(conf, 1, true, "/", "-move");
      assertTrue(outStr.contains(NamenodeFsck.CORRUPT_STATUS));

      // Check to make sure we have healthy filesystem
      outStr = runFsck(conf, 0, true, "/");
      assertTrue(outStr.contains(NamenodeFsck.HEALTHY_STATUS));
      util.cleanup(fs, topDir);
      if (fs != null) {
        try {
          fs.close();
        } catch (Exception e) {
        }
      }
      cluster.shutdown();
    } finally {
      if (fs != null) {
        try {
          fs.close();
        } catch (Exception e) {
        }
      }
      if (cluster != null) {
        cluster.shutdown();
      }
    }
  }

  public void testFsckOpenFiles() throws Exception {
    DFSTestUtil util = new DFSTestUtil("TestFsck", 4, 3, 8 * 1024);
    MiniDFSCluster cluster = null;
    FileSystem fs = null;
    try {
      Configuration conf = new Configuration();
      conf.setLong("dfs.blockreport.intervalMsec", 10000L);
      cluster = new MiniDFSCluster(conf, 4, true, null);
      String topDir = "/srcdat";
      String randomString = "HADOOP  ";
      fs = cluster.getFileSystem();
      cluster.waitActive();
      util.createFiles(fs, topDir);
      util.waitReplication(fs, topDir, (short) 3);
      String outStr = runFsck(conf, 0, true, "/");
      assertTrue(outStr.contains(NamenodeFsck.HEALTHY_STATUS));
      // Open a file for writing and do not close for now
      Path openFile = new Path(topDir + "/openFile");
      FSDataOutputStream out = fs.create(openFile);
      int writeCount = 0;
      while (writeCount != 100) {
        out.write(randomString.getBytes());
        writeCount++;
      }
      // We expect the filesystem to be HEALTHY and show one open file
      outStr = runFsck(conf, 0, true, topDir);
      System.out.println(outStr);
      assertTrue(outStr.contains(NamenodeFsck.HEALTHY_STATUS));
      assertFalse(outStr.contains("OPENFORWRITE"));
      // Use -openforwrite option to list open files
      outStr = runFsck(conf, 0, true, topDir, "-openforwrite");
      System.out.println(outStr);
      assertTrue(outStr.contains("OPENFORWRITE"));
      assertTrue(outStr.contains("openFile"));
      // Close the file
      out.close();
      // Now, fsck should show HEALTHY fs and should not show any open files
      outStr = runFsck(conf, 0, true, topDir);
      System.out.println(outStr);
      assertTrue(outStr.contains(NamenodeFsck.HEALTHY_STATUS));
      assertFalse(outStr.contains("OPENFORWRITE"));
      util.cleanup(fs, topDir);
      if (fs != null) {
        try {
          fs.close();
        } catch (Exception e) {
        }
      }
      cluster.shutdown();
    } finally {
      if (fs != null) {
        try {
          fs.close();
        } catch (Exception e) {
        }
      }
      if (cluster != null) {
        cluster.shutdown();
      }
    }
  }

  public void testCorruptBlock() throws Exception {
    Configuration conf = new Configuration();
    conf.setLong("dfs.blockreport.intervalMsec", 1000);
    FileSystem fs = null;
    DFSClient dfsClient = null;
    LocatedBlocks blocks = null;
    int replicaCount = 0;
    Random random = new Random();
    String outStr = null;

    MiniDFSCluster cluster = null;
    try {
      cluster = new MiniDFSCluster(conf, 3, true, null);
      cluster.waitActive();
      fs = cluster.getFileSystem();
      Path file1 = new Path("/testCorruptBlock");
      DFSTestUtil.createFile(fs, file1, 1024, (short) 3, 0);
      // Wait until file replication has completed
      DFSTestUtil.waitReplication(fs, file1, (short) 3);
      String block = DFSTestUtil.getFirstBlock(fs, file1).getBlockName();

      // Make sure filesystem is in healthy state
      outStr = runFsck(conf, 0, true, "/");
      System.out.println(outStr);
      assertTrue(outStr.contains(NamenodeFsck.HEALTHY_STATUS));

      // corrupt replicas 
      for (int i = 0; i < 6; i++) {
        File blockFile = new File(cluster.getBlockDirectory("data" + (i + 1)), block);
        if (blockFile.exists()) {
          RandomAccessFile raFile = new RandomAccessFile(blockFile, "rw");
          FileChannel channel = raFile.getChannel();
          String badString = "BADBAD";
          int rand = random.nextInt((int) channel.size() / 2);
          raFile.seek(rand);
          raFile.write(badString.getBytes());
          raFile.close();
        }
      }
      // Read the file to trigger reportBadBlocks
      try {
        IOUtils.copyBytes(fs.open(file1), new IOUtils.NullOutputStream(), conf,
          true);
      } catch (IOException ie) {
        // Ignore exception
      }

      dfsClient = new DFSClient(new InetSocketAddress("localhost",
        cluster.getNameNodePort()), conf);
      blocks = dfsClient.namenode.
        getBlockLocations(file1.toString(), 0, Long.MAX_VALUE);
      replicaCount = blocks.get(0).getLocations().length;
      while (replicaCount != 3) {
        try {
          Thread.sleep(100);
        } catch (InterruptedException ignore) {
        }
        blocks = dfsClient.namenode.
          getBlockLocations(file1.toString(), 0, Long.MAX_VALUE);
        replicaCount = blocks.get(0).getLocations().length;
      }
      assertTrue(blocks.get(0).isCorrupt());

      // Check if fsck reports the same
      outStr = runFsck(conf, 1, true, "/");
      System.out.println(outStr);
      assertTrue(outStr.contains(NamenodeFsck.CORRUPT_STATUS));
      assertTrue(outStr.contains("testCorruptBlock"));
    } finally {
      if (cluster != null) {
        cluster.shutdown();
      }
    }
  }

  /**
   * Test if fsck can return -1 in case of failure
   *
   * @throws Exception
   */
  public void testFsckError() throws Exception {
    MiniDFSCluster cluster = null;
    try {
      // bring up a one-node cluster
      Configuration conf = new Configuration();
      cluster = new MiniDFSCluster(conf, 1, true, null);
      String fileName = "/test.txt";
      Path filePath = new Path(fileName);
      FileSystem fs = cluster.getFileSystem();

      // create a one-block file
      DFSTestUtil.createFile(fs, filePath, 1L, (short) 1, 1L);
      DFSTestUtil.waitReplication(fs, filePath, (short) 1);

      // intentionally corrupt NN data structure
      INodeFile node = (INodeFile) cluster.getNameNode().namesystem.dir.rootDir.getNode(fileName);
      assertEquals(node.blocks.length, 1);
      node.blocks[0].setNumBytes(-1L);  // set the block length to be negative

      // run fsck and expect a failure with -1 as the error code
      String outStr = runFsck(conf, -1, true, fileName);
      System.out.println(outStr);
      assertTrue(outStr.contains(NamenodeFsck.FAILURE_STATUS));

      // clean up file system
      fs.delete(filePath, true);
    } finally {
      if (cluster != null) {
        cluster.shutdown();
      }
    }
  }

  public void testListCorruptOpenFilesForWrite() throws Exception {
    MiniDFSCluster cluster = null;

    try {
      Configuration conf = new Configuration();
//      conf.setInt("dfs.block.size", 100 * 1024);
      cluster = new MiniDFSCluster(conf, 3, true, null);
      // immediately expire lesaes for testing

      FileSystem fileSystem = cluster.getFileSystem();

      FSDataOutputStream out1 = fileSystem.create(new Path("/file1"));
      out1.write(DFSTestUtil.generateSequentialBytes(0, 1024 * 1024));
      out1.close();

      FSDataOutputStream out2 = fileSystem.create(new Path("/file2"));
      out2.write(DFSTestUtil.generateSequentialBytes(0, 1024 * 1024));
      out2.sync();

      FSNamesystem namesystem = cluster.getNameNode().getNamesystem();

      File rootDataDir = new File(cluster.getDataDirectory());
      
      FSNamesystemAdapter.corruptFileForTesting("/file2", namesystem);
      
      ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
      final PrintWriter writer = new PrintWriter(byteArrayOutputStream);
      HttpServletResponse response = new HttpServletResponseStub() {
        @Override
        public PrintWriter getWriter() throws IOException {
          return writer;
        }
      };
      Map<String, String[]> pmap = new HashMap<String, String[]>();
      pmap.put("path", new String[]{"/"});
      pmap.put("openforwrite", new String[]{"1"});
      pmap.put("corruptfiles", new String[]{"1"});

      NamenodeFsck fsck =
        new NamenodeFsck(conf, cluster.getNameNode(), pmap, response);

      fsck.fsck();

      String outStr = byteArrayOutputStream.toString();
      
      LOG.info(outStr);
      
      assertTrue("fsck output should indicate corrupt files", outStr.toLowerCase().contains("/file2"));
      out2.close();
    } finally {
      if (cluster != null) {
        cluster.shutdown();
      }
    }
  }

  /** check if option -list-corruptfiles of fsck command works properly */
  public void testFsckListCorruptFilesBlocks() throws Exception {
    Configuration conf = new Configuration();
    conf.setLong("dfs.blockreport.intervalMsec", 1000);
    conf.setInt("dfs.datanode.directoryscan.interval", 1);
    conf.setBoolean("dfs.permissions", false);
    FileSystem fs = null;
    
    MiniDFSCluster cluster = null;
    try {
      cluster = new MiniDFSCluster(conf, 1, true, null);
      cluster.waitActive();
      fs = cluster.getFileSystem();
      DFSTestUtil util = new DFSTestUtil("testGetCorruptFiles", 3, 1, 1024);
      util.createFiles(fs, "/corruptData", (short) 1);
      util.waitReplication(fs, "/corruptData", (short) 1);
      
      // String outStr = runFsck(conf, 0, true, "/corruptData",
      // "-list-corruptfileblocks");
      String outStr = runFsck(conf, 0, false, "/corruptData",
                              "-list-corruptfileblocks");
      System.out.println("1. good fsck out: " + outStr);
      assertTrue(outStr.contains("has 0 CORRUPT files"));
      // delete the blocks
      for (int i=0; i<8; i++) {
        File data_dir = cluster.getBlockDirectory("data" + (i + 1));
        File[] blocks = data_dir.listFiles();
        if (blocks == null)
          continue;
        
        for (int idx = 0; idx < blocks.length; idx++) {
          if (!blocks[idx].getName().startsWith("blk_")) {
            continue;
          }
          assertTrue("Cannot remove file.", blocks[idx].delete());
        }
      }
      
      // wait for the namenode to see the corruption
      final NameNode namenode = cluster.getNameNode();
      CorruptFileBlocks corruptFileBlocks = namenode
        .listCorruptFileBlocks("/corruptData", null);
      int numCorrupt = corruptFileBlocks.getFiles().length;
      while (numCorrupt < 3) {
        Thread.sleep(1000);
        corruptFileBlocks = namenode
          .listCorruptFileBlocks("/corruptData", null);
        numCorrupt = corruptFileBlocks.getFiles().length;
      }
      outStr = runFsck(conf, -1, true, "/corruptData",
                       "-list-corruptfileblocks");
      System.out.println("2. bad fsck out: " + outStr);
      assertTrue(outStr.contains("has 3 CORRUPT files"));
      
      // Do a listing on a dir which doesn't have any corrupt blocks and validate
      util.createFiles(fs, "/goodData");
      outStr = runFsck(conf, 0, true, "/goodData", "-list-corruptfileblocks");
      System.out.println("3. good fsck out: " + outStr);
      assertTrue(outStr.contains("has 0 CORRUPT files"));
      util.cleanup(fs,"/corruptData");
      util.cleanup(fs, "/goodData");
    } finally {
      if (cluster != null) {cluster.shutdown();}
    }
  }


}