Java Code Examples for org.apache.hadoop.hdfs.protocol.AlreadyBeingCreatedException

The following examples show how to use org.apache.hadoop.hdfs.protocol.AlreadyBeingCreatedException. These examples are extracted from open source projects. You can vote up the ones you like or vote down the ones you don't like, and go to the original project or source file by following the links above each example. You may check out the related API usage on the sidebar.
Example 1
Source Project: hadoop   Source File: NameNodeConnector.java    License: Apache License 2.0 6 votes vote down vote up
/**
 * The idea for making sure that there is no more than one instance
 * running in an HDFS is to create a file in the HDFS, writes the hostname
 * of the machine on which the instance is running to the file, but did not
 * close the file until it exits. 
 * 
 * This prevents the second instance from running because it can not
 * creates the file while the first one is running.
 * 
 * This method checks if there is any running instance. If no, mark yes.
 * Note that this is an atomic operation.
 * 
 * @return null if there is a running instance;
 *         otherwise, the output stream to the newly created file.
 */
private OutputStream checkAndMarkRunning() throws IOException {
  try {
    if (fs.exists(idPath)) {
      // try appending to it so that it will fail fast if another balancer is
      // running.
      IOUtils.closeStream(fs.append(idPath));
      fs.delete(idPath, true);
    }
    final FSDataOutputStream fsout = fs.create(idPath, false);
    // mark balancer idPath to be deleted during filesystem closure
    fs.deleteOnExit(idPath);
    if (write2IdFile) {
      fsout.writeBytes(InetAddress.getLocalHost().getHostName());
      fsout.hflush();
    }
    return fsout;
  } catch(RemoteException e) {
    if(AlreadyBeingCreatedException.class.getName().equals(e.getClassName())){
      return null;
    } else {
      throw e;
    }
  }
}
 
Example 2
Source Project: big-c   Source File: NameNodeConnector.java    License: Apache License 2.0 6 votes vote down vote up
/**
 * The idea for making sure that there is no more than one instance
 * running in an HDFS is to create a file in the HDFS, writes the hostname
 * of the machine on which the instance is running to the file, but did not
 * close the file until it exits. 
 * 
 * This prevents the second instance from running because it can not
 * creates the file while the first one is running.
 * 
 * This method checks if there is any running instance. If no, mark yes.
 * Note that this is an atomic operation.
 * 
 * @return null if there is a running instance;
 *         otherwise, the output stream to the newly created file.
 */
private OutputStream checkAndMarkRunning() throws IOException {
  try {
    if (fs.exists(idPath)) {
      // try appending to it so that it will fail fast if another balancer is
      // running.
      IOUtils.closeStream(fs.append(idPath));
      fs.delete(idPath, true);
    }
    final FSDataOutputStream fsout = fs.create(idPath, false);
    // mark balancer idPath to be deleted during filesystem closure
    fs.deleteOnExit(idPath);
    if (write2IdFile) {
      fsout.writeBytes(InetAddress.getLocalHost().getHostName());
      fsout.hflush();
    }
    return fsout;
  } catch(RemoteException e) {
    if(AlreadyBeingCreatedException.class.getName().equals(e.getClassName())){
      return null;
    } else {
      throw e;
    }
  }
}
 
Example 3
Source Project: pravega   Source File: HDFSExceptionHelpers.java    License: Apache License 2.0 6 votes vote down vote up
/**
 * Translates HDFS specific Exceptions to Pravega-equivalent Exceptions.
 *
 * @param segmentName Name of the stream segment on which the exception occurs.
 * @param e           The exception to be translated.
 * @return  The exception to be thrown.
 */
static <T> StreamSegmentException convertException(String segmentName, Throwable e) {
    if (e instanceof RemoteException) {
        e = ((RemoteException) e).unwrapRemoteException();
    }

    if (e instanceof PathNotFoundException || e instanceof FileNotFoundException) {
        return new StreamSegmentNotExistsException(segmentName, e);
    } else if (e instanceof FileAlreadyExistsException || e instanceof AlreadyBeingCreatedException) {
        return new StreamSegmentExistsException(segmentName, e);
    } else if (e instanceof AclException) {
        return new StreamSegmentSealedException(segmentName, e);
    } else {
        throw Exceptions.sneakyThrow(e);
    }
}
 
Example 4
Source Project: hbase   Source File: HBaseFsck.java    License: Apache License 2.0 6 votes vote down vote up
@Override
public FSDataOutputStream call() throws IOException {
  try {
    FileSystem fs = CommonFSUtils.getCurrentFileSystem(this.conf);
    FsPermission defaultPerms =
      CommonFSUtils.getFilePermissions(fs, this.conf, HConstants.DATA_FILE_UMASK_KEY);
    Path tmpDir = getTmpDir(conf);
    this.hbckLockPath = new Path(tmpDir, HBCK_LOCK_FILE);
    fs.mkdirs(tmpDir);
    final FSDataOutputStream out = createFileWithRetries(fs, this.hbckLockPath, defaultPerms);
    out.writeBytes(InetAddress.getLocalHost().toString());
    // Add a note into the file we write on why hbase2 is writing out an hbck1 lock file.
    out.writeBytes(" Written by an hbase-2.x Master to block an " +
        "attempt by an hbase-1.x HBCK tool making modification to state. " +
        "See 'HBCK must match HBase server version' in the hbase refguide.");
    out.flush();
    return out;
  } catch(RemoteException e) {
    if(AlreadyBeingCreatedException.class.getName().equals(e.getClassName())){
      return null;
    } else {
      throw e;
    }
  }
}
 
Example 5
Source Project: RDFS   Source File: DFSClient.java    License: Apache License 2.0 6 votes vote down vote up
private static ClientProtocol createNamenode(ClientProtocol rpcNamenode,
    Configuration conf)
  throws IOException {
  long sleepTime = conf.getLong("dfs.client.rpc.retry.sleep",
      LEASE_SOFTLIMIT_PERIOD);
  RetryPolicy createPolicy = RetryPolicies.retryUpToMaximumCountWithFixedSleep(
      5, sleepTime, TimeUnit.MILLISECONDS);

  Map<Class<? extends Exception>,RetryPolicy> remoteExceptionToPolicyMap =
    new HashMap<Class<? extends Exception>, RetryPolicy>();
  remoteExceptionToPolicyMap.put(AlreadyBeingCreatedException.class, createPolicy);

  Map<Class<? extends Exception>,RetryPolicy> exceptionToPolicyMap =
    new HashMap<Class<? extends Exception>, RetryPolicy>();
  exceptionToPolicyMap.put(RemoteException.class,
      RetryPolicies.retryByRemoteException(
          RetryPolicies.TRY_ONCE_THEN_FAIL, remoteExceptionToPolicyMap));
  RetryPolicy methodPolicy = RetryPolicies.retryByException(
      RetryPolicies.TRY_ONCE_THEN_FAIL, exceptionToPolicyMap);
  Map<String,RetryPolicy> methodNameToPolicyMap = new HashMap<String,RetryPolicy>();

  methodNameToPolicyMap.put("create", methodPolicy);

  return (ClientProtocol) RetryProxy.create(ClientProtocol.class,
      rpcNamenode, methodNameToPolicyMap);
}
 
Example 6
Source Project: jstorm   Source File: FileLock.java    License: Apache License 2.0 6 votes vote down vote up
/**
 * Takes ownership of the lock file if possible.
 * @param lockFile
 * @param lastEntry   last entry in the lock file. this param is an optimization.
 *                    we dont scan the lock file again to find its last entry here since
 *                    its already been done once by the logic used to check if the lock
 *                    file is stale. so this value comes from that earlier scan.
 * @param spoutId     spout id
 * @throws IOException if unable to acquire
 * @return null if lock File is not recoverable
 */
public static FileLock takeOwnership(FileSystem fs, Path lockFile, LogEntry lastEntry, String spoutId)
        throws IOException {
  try {
    if(fs instanceof DistributedFileSystem ) {
      if( !((DistributedFileSystem) fs).recoverLease(lockFile) ) {
        LOG.warn("Unable to recover lease on lock file {} right now. Cannot transfer ownership. Will need to try later. Spout = {}", lockFile, spoutId);
        return null;
      }
    }
    return new FileLock(fs, lockFile, spoutId, lastEntry);
  } catch (IOException e) {
    if (e instanceof RemoteException &&
            ((RemoteException) e).unwrapRemoteException() instanceof AlreadyBeingCreatedException) {
      LOG.warn("Lock file " + lockFile + "is currently open. Cannot transfer ownership now. Will need to try later. Spout= " + spoutId, e);
      return null;
    } else { // unexpected error
      LOG.warn("Cannot transfer ownership now for lock file " + lockFile + ". Will need to try later. Spout =" + spoutId, e);
      throw e;
    }
  }
}
 
Example 7
Source Project: DataLink   Source File: RemoteUtil.java    License: Apache License 2.0 5 votes vote down vote up
public static void tryRemoteClose(String hdfsFilePath, Exception e) {
    try {
        if (e instanceof RemoteException) {
            RemoteException re = (RemoteException) e;
            String className = re.getClassName();
            if (className.equals(AlreadyBeingCreatedException.class.getName()) && e.getMessage().contains(RECREATE_IDENTIFIER)) {
                logger.info("stream remote close begin for file : " + hdfsFilePath);
                colseInternal(hdfsFilePath, parseIp(e.getMessage()));
                logger.info("stream remote close end for file : " + hdfsFilePath);
            }
        }
    } catch (Exception ex) {
        logger.error("stream remote close failed for file : " + hdfsFilePath, ex);
    }
}
 
Example 8
Source Project: hadoop   Source File: ClientNamenodeProtocolTranslatorPB.java    License: Apache License 2.0 5 votes vote down vote up
@Override
public HdfsFileStatus create(String src, FsPermission masked,
    String clientName, EnumSetWritable<CreateFlag> flag,
    boolean createParent, short replication, long blockSize, 
    CryptoProtocolVersion[] supportedVersions)
    throws AccessControlException, AlreadyBeingCreatedException,
    DSQuotaExceededException, FileAlreadyExistsException,
    FileNotFoundException, NSQuotaExceededException,
    ParentNotDirectoryException, SafeModeException, UnresolvedLinkException,
    IOException {
  CreateRequestProto.Builder builder = CreateRequestProto.newBuilder()
      .setSrc(src)
      .setMasked(PBHelper.convert(masked))
      .setClientName(clientName)
      .setCreateFlag(PBHelper.convertCreateFlag(flag))
      .setCreateParent(createParent)
      .setReplication(replication)
      .setBlockSize(blockSize);
  builder.addAllCryptoProtocolVersion(PBHelper.convert(supportedVersions));
  CreateRequestProto req = builder.build();
  try {
    CreateResponseProto res = rpcProxy.create(null, req);
    return res.hasFs() ? PBHelper.convert(res.getFs()) : null;
  } catch (ServiceException e) {
    throw ProtobufHelper.getRemoteException(e);
  }

}
 
Example 9
Source Project: hadoop   Source File: TestFileAppend.java    License: Apache License 2.0 5 votes vote down vote up
/** Test two consecutive appends on a file with a full block. */
@Test
public void testAppendTwice() throws Exception {
  Configuration conf = new HdfsConfiguration();
  MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).build();
  final FileSystem fs1 = cluster.getFileSystem();
  final FileSystem fs2 = AppendTestUtil.createHdfsWithDifferentUsername(conf);
  try {

    final Path p = new Path("/testAppendTwice/foo");
    final int len = 1 << 16;
    final byte[] fileContents = AppendTestUtil.initBuffer(len);

    {
      // create a new file with a full block.
      FSDataOutputStream out = fs2.create(p, true, 4096, (short)1, len);
      out.write(fileContents, 0, len);
      out.close();
    }

    //1st append does not add any data so that the last block remains full
    //and the last block in INodeFileUnderConstruction is a BlockInfo
    //but not BlockInfoUnderConstruction. 
    fs2.append(p);
    
    //2nd append should get AlreadyBeingCreatedException
    fs1.append(p);
    Assert.fail();
  } catch(RemoteException re) {
    AppendTestUtil.LOG.info("Got an exception:", re);
    Assert.assertEquals(AlreadyBeingCreatedException.class.getName(),
        re.getClassName());
  } finally {
    fs2.close();
    fs1.close();
    cluster.shutdown();
  }
}
 
Example 10
Source Project: hadoop   Source File: TestFileAppend.java    License: Apache License 2.0 5 votes vote down vote up
/** Test two consecutive appends on a file with a full block. */
@Test
public void testAppend2Twice() throws Exception {
  Configuration conf = new HdfsConfiguration();
  MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).build();
  final DistributedFileSystem fs1 = cluster.getFileSystem();
  final FileSystem fs2 = AppendTestUtil.createHdfsWithDifferentUsername(conf);
  try {
    final Path p = new Path("/testAppendTwice/foo");
    final int len = 1 << 16;
    final byte[] fileContents = AppendTestUtil.initBuffer(len);

    {
      // create a new file with a full block.
      FSDataOutputStream out = fs2.create(p, true, 4096, (short)1, len);
      out.write(fileContents, 0, len);
      out.close();
    }

    //1st append does not add any data so that the last block remains full
    //and the last block in INodeFileUnderConstruction is a BlockInfo
    //but not BlockInfoUnderConstruction.
    ((DistributedFileSystem) fs2).append(p,
        EnumSet.of(CreateFlag.APPEND, CreateFlag.NEW_BLOCK), 4096, null);

    // 2nd append should get AlreadyBeingCreatedException
    fs1.append(p);
    Assert.fail();
  } catch(RemoteException re) {
    AppendTestUtil.LOG.info("Got an exception:", re);
    Assert.assertEquals(AlreadyBeingCreatedException.class.getName(),
        re.getClassName());
  } finally {
    fs2.close();
    fs1.close();
    cluster.shutdown();
  }
}
 
Example 11
Source Project: big-c   Source File: ClientNamenodeProtocolTranslatorPB.java    License: Apache License 2.0 5 votes vote down vote up
@Override
public HdfsFileStatus create(String src, FsPermission masked,
    String clientName, EnumSetWritable<CreateFlag> flag,
    boolean createParent, short replication, long blockSize, 
    CryptoProtocolVersion[] supportedVersions)
    throws AccessControlException, AlreadyBeingCreatedException,
    DSQuotaExceededException, FileAlreadyExistsException,
    FileNotFoundException, NSQuotaExceededException,
    ParentNotDirectoryException, SafeModeException, UnresolvedLinkException,
    IOException {
  CreateRequestProto.Builder builder = CreateRequestProto.newBuilder()
      .setSrc(src)
      .setMasked(PBHelper.convert(masked))
      .setClientName(clientName)
      .setCreateFlag(PBHelper.convertCreateFlag(flag))
      .setCreateParent(createParent)
      .setReplication(replication)
      .setBlockSize(blockSize);
  builder.addAllCryptoProtocolVersion(PBHelper.convert(supportedVersions));
  CreateRequestProto req = builder.build();
  try {
    CreateResponseProto res = rpcProxy.create(null, req);
    return res.hasFs() ? PBHelper.convert(res.getFs()) : null;
  } catch (ServiceException e) {
    throw ProtobufHelper.getRemoteException(e);
  }

}
 
Example 12
Source Project: big-c   Source File: TestFileAppend.java    License: Apache License 2.0 5 votes vote down vote up
/** Test two consecutive appends on a file with a full block. */
@Test
public void testAppendTwice() throws Exception {
  Configuration conf = new HdfsConfiguration();
  MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).build();
  final FileSystem fs1 = cluster.getFileSystem();
  final FileSystem fs2 = AppendTestUtil.createHdfsWithDifferentUsername(conf);
  try {

    final Path p = new Path("/testAppendTwice/foo");
    final int len = 1 << 16;
    final byte[] fileContents = AppendTestUtil.initBuffer(len);

    {
      // create a new file with a full block.
      FSDataOutputStream out = fs2.create(p, true, 4096, (short)1, len);
      out.write(fileContents, 0, len);
      out.close();
    }

    //1st append does not add any data so that the last block remains full
    //and the last block in INodeFileUnderConstruction is a BlockInfo
    //but not BlockInfoUnderConstruction. 
    fs2.append(p);
    
    //2nd append should get AlreadyBeingCreatedException
    fs1.append(p);
    Assert.fail();
  } catch(RemoteException re) {
    AppendTestUtil.LOG.info("Got an exception:", re);
    Assert.assertEquals(AlreadyBeingCreatedException.class.getName(),
        re.getClassName());
  } finally {
    fs2.close();
    fs1.close();
    cluster.shutdown();
  }
}
 
Example 13
Source Project: big-c   Source File: TestFileAppend.java    License: Apache License 2.0 5 votes vote down vote up
/** Test two consecutive appends on a file with a full block. */
@Test
public void testAppend2Twice() throws Exception {
  Configuration conf = new HdfsConfiguration();
  MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).build();
  final DistributedFileSystem fs1 = cluster.getFileSystem();
  final FileSystem fs2 = AppendTestUtil.createHdfsWithDifferentUsername(conf);
  try {
    final Path p = new Path("/testAppendTwice/foo");
    final int len = 1 << 16;
    final byte[] fileContents = AppendTestUtil.initBuffer(len);

    {
      // create a new file with a full block.
      FSDataOutputStream out = fs2.create(p, true, 4096, (short)1, len);
      out.write(fileContents, 0, len);
      out.close();
    }

    //1st append does not add any data so that the last block remains full
    //and the last block in INodeFileUnderConstruction is a BlockInfo
    //but not BlockInfoUnderConstruction.
    ((DistributedFileSystem) fs2).append(p,
        EnumSet.of(CreateFlag.APPEND, CreateFlag.NEW_BLOCK), 4096, null);

    // 2nd append should get AlreadyBeingCreatedException
    fs1.append(p);
    Assert.fail();
  } catch(RemoteException re) {
    AppendTestUtil.LOG.info("Got an exception:", re);
    Assert.assertEquals(AlreadyBeingCreatedException.class.getName(),
        re.getClassName());
  } finally {
    fs2.close();
    fs1.close();
    cluster.shutdown();
  }
}
 
Example 14
Source Project: beam   Source File: HDFSSynchronizationTest.java    License: Apache License 2.0 5 votes vote down vote up
@Test
public void testCatchingRemoteException() throws IOException {
  FileSystem mockedFileSystem = Mockito.mock(FileSystem.class);
  RemoteException thrownException =
      new RemoteException(AlreadyBeingCreatedException.class.getName(), "Failed to CREATE_FILE");
  Mockito.when(mockedFileSystem.createNewFile(Mockito.any())).thenThrow(thrownException);

  HDFSSynchronization synchronization =
      new HDFSSynchronization("someDir", (conf) -> mockedFileSystem);

  assertFalse(synchronization.tryAcquireJobLock(configuration));
}
 
Example 15
Source Project: hbase   Source File: TestOverwriteFileUnderConstruction.java    License: Apache License 2.0 5 votes vote down vote up
@Test
public void testNotOverwrite() throws IOException {
  Path file = new Path("/" + name.getMethodName());
  try (FSDataOutputStream out1 = FS.create(file)) {
    try {
      FS.create(file, false);
      fail("Should fail as there is a file with the same name which is being written");
    } catch (RemoteException e) {
      // expected
      assertThat(e.unwrapRemoteException(), instanceOf(AlreadyBeingCreatedException.class));
    }
  }
}
 
Example 16
Source Project: RDFS   Source File: TestLeaseRecovery3.java    License: Apache License 2.0 5 votes vote down vote up
private void recoverLeaseUsingCreate(Path filepath) throws IOException {
  Configuration conf2 = new Configuration(conf);
  String username = UserGroupInformation.getCurrentUGI().getUserName()+"_1";
  UnixUserGroupInformation.saveToConf(conf2,
      UnixUserGroupInformation.UGI_PROPERTY_NAME,
      new UnixUserGroupInformation(username, new String[]{"supergroup"}));
  FileSystem dfs2 = FileSystem.get(conf2);

  boolean done = false;
  for(int i = 0; i < 10 && !done; i++) {
    AppendTestUtil.LOG.info("i=" + i);
    try {
      dfs2.create(filepath, false, bufferSize, (short)1, BLOCK_SIZE);
      fail("Creation of an existing file should never succeed.");
    } catch (IOException ioe) {
      final String message = ioe.getMessage();
      if (message.contains("file exists")) {
        AppendTestUtil.LOG.info("done", ioe);
        done = true;
      }
      else if (message.contains(AlreadyBeingCreatedException.class.getSimpleName())) {
        AppendTestUtil.LOG.info("GOOD! got " + message);
      }
      else {
        AppendTestUtil.LOG.warn("UNEXPECTED IOException", ioe);
      }
    }

    if (!done) {
      AppendTestUtil.LOG.info("sleep " + 5000 + "ms");
      try {Thread.sleep(5000);} catch (InterruptedException e) {}
    }
  }
  assertTrue(done);

}
 
Example 17
Source Project: RDFS   Source File: TestLeaseRecovery2.java    License: Apache License 2.0 5 votes vote down vote up
private void recoverLeaseUsingCreate(Path filepath) throws IOException {
  Configuration conf2 = new Configuration(conf);
  String username = UserGroupInformation.getCurrentUGI().getUserName()+"_1";
  UnixUserGroupInformation.saveToConf(conf2,
      UnixUserGroupInformation.UGI_PROPERTY_NAME,
      new UnixUserGroupInformation(username, new String[]{"supergroup"}));
  FileSystem dfs2 = FileSystem.get(conf2);

  boolean done = false;
  for(int i = 0; i < 10 && !done; i++) {
    AppendTestUtil.LOG.info("i=" + i);
    try {
      dfs2.create(filepath, false, bufferSize, (short)1, BLOCK_SIZE);
      fail("Creation of an existing file should never succeed.");
    } catch (IOException ioe) {
      final String message = ioe.getMessage();
      if (message.contains("file exists")) {
        AppendTestUtil.LOG.info("done", ioe);
        done = true;
      }
      else if (message.contains(AlreadyBeingCreatedException.class.getSimpleName())) {
        AppendTestUtil.LOG.info("GOOD! got " + message);
      }
      else {
        AppendTestUtil.LOG.warn("UNEXPECTED IOException", ioe);
      }
    }

    if (!done) {
      AppendTestUtil.LOG.info("sleep " + 5000 + "ms");
      try {Thread.sleep(5000);} catch (InterruptedException e) {}
    }
  }
  assertTrue(done);

}
 
Example 18
Source Project: RDFS   Source File: Balancer.java    License: Apache License 2.0 5 votes vote down vote up
private OutputStream checkAndMarkRunningBalancer() throws IOException {
  try {
    DataOutputStream out = fs.create(BALANCER_ID_PATH);
    out. writeBytes(InetAddress.getLocalHost().getHostName());
    out.flush();
    return out;
  } catch(RemoteException e) {
    if(AlreadyBeingCreatedException.class.getName().equals(e.getClassName())){
      return null;
    } else {
      throw e;
    }
  }
}
 
Example 19
Source Project: hudi   Source File: HoodieLogFormatWriter.java    License: Apache License 2.0 4 votes vote down vote up
private void handleAppendExceptionOrRecoverLease(Path path, RemoteException e)
    throws IOException, InterruptedException {
  if (e.getMessage().contains(APPEND_UNAVAILABLE_EXCEPTION_MESSAGE)) {
    // This issue happens when all replicas for a file are down and/or being decommissioned.
    // The fs.append() API could append to the last block for a file. If the last block is full, a new block is
    // appended to. In a scenario when a lot of DN's are decommissioned, it can happen that DN's holding all
    // replicas for a block/file are decommissioned together. During this process, all these blocks will start to
    // get replicated to other active DataNodes but this process might take time (can be of the order of few
    // hours). During this time, if a fs.append() API is invoked for a file whose last block is eligible to be
    // appended to, then the NN will throw an exception saying that it couldn't find any active replica with the
    // last block. Find more information here : https://issues.apache.org/jira/browse/HDFS-6325
    LOG.warn("Failed to open an append stream to the log file. Opening a new log file..", e);
    // Rollover the current log file (since cannot get a stream handle) and create new one
    this.logFile = logFile.rollOver(fs, rolloverLogWriteToken);
    createNewFile();
  } else if (e.getClassName().contentEquals(AlreadyBeingCreatedException.class.getName())) {
    LOG.warn("Another task executor writing to the same log file(" + logFile + ". Rolling over");
    // Rollover the current log file (since cannot get a stream handle) and create new one
    this.logFile = logFile.rollOver(fs, rolloverLogWriteToken);
    createNewFile();
  } else if (e.getClassName().contentEquals(RecoveryInProgressException.class.getName())
      && (fs instanceof DistributedFileSystem)) {
    // this happens when either another task executor writing to this file died or
    // data node is going down. Note that we can only try to recover lease for a DistributedFileSystem.
    // ViewFileSystem unfortunately does not support this operation
    LOG.warn("Trying to recover log on path " + path);
    if (FSUtils.recoverDFSFileLease((DistributedFileSystem) fs, path)) {
      LOG.warn("Recovered lease on path " + path);
      // try again
      this.output = fs.append(path, bufferSize);
    } else {
      LOG.warn("Failed to recover lease on path " + path);
      throw new HoodieException(e);
    }
  } else {
    // When fs.append() has failed and an exception is thrown, by closing the output stream
    // we shall force hdfs to release the lease on the log file. When Spark retries this task (with
    // new attemptId, say taskId.1) it will be able to acquire lease on the log file (as output stream was
    // closed properly by taskId.0).
    //
    // If close() call were to fail throwing an exception, our best bet is to rollover to a new log file.
    try {
      close();
      // output stream has been successfully closed and lease on the log file has been released,
      // before throwing an exception for the append failure.
      throw new HoodieIOException("Failed to append to the output stream ", e);
    } catch (Exception ce) {
      LOG.warn("Failed to close the output stream for " + fs.getClass().getName() + " on path " + path
          + ". Rolling over to a new log file.");
      this.logFile = logFile.rollOver(fs, rolloverLogWriteToken);
      createNewFile();
    }
  }
}
 
Example 20
Source Project: RDFS   Source File: DistributedAvatarFileSystem.java    License: Apache License 2.0 4 votes vote down vote up
@Override
public void create(final String src, final FsPermission masked,
    final String clientName, final boolean overwrite,
    final boolean createParent,
    final short replication, final long blockSize) throws IOException {
  (new MutableFSCaller<Boolean>() {
    @Override
    Boolean call(int retries) throws IOException {
      if (retries > 0) {
        // This I am not sure about, because of lease holder I can tell if
        // it
        // was me or not with a high level of certainty
        FileStatus stat = namenode.getFileInfo(src);
        if (stat != null) {
          /*
           * Since the file exists already we need to perform a number of
           * checks to see if it was created by us before the failover
           */

          if (stat.getBlockSize() == blockSize
              && stat.getReplication() == replication && stat.getLen() == 0
              && stat.getPermission().equals(masked)) {
            // The file has not been written to and it looks exactly like
            // the file we were trying to create. Last check:
            // call create again and then parse the exception.
            // Two cases:
            // it was the same client who created the old file
            // or it was created by someone else - fail
            try {
              namenode.create(src, masked, clientName, overwrite,
                  createParent, replication, blockSize);
            } catch (RemoteException re) {
              if (re.unwrapRemoteException() instanceof AlreadyBeingCreatedException) {
                AlreadyBeingCreatedException aex = (AlreadyBeingCreatedException) re
                    .unwrapRemoteException();
                if (aex.getMessage().contains(
                    "current leaseholder is trying to recreate file")) {
                  namenode.delete(src, false);
                } else {
                  throw re;
                }
              } else {
                throw re;
              }
            }
          }
        }
      }
      namenode.create(src, masked, clientName, overwrite, createParent, replication,
          blockSize);
      return true;
    }
  }).callFS();
}