org.apache.hadoop.hbase.snapshot.SnapshotManifest Java Examples

/**
 * get region infos
 *
 * @param zookeeperQuorum     zookeeper quorum
 * @param zookeeperClientPort zookeeper client port
 * @param hBaseRootDir        HBase root dir
 * @param snapshotName        snapshot name
 * @return region info list
 * @throws IOException IOException
 */
public static List<HRegionInfo> getRegionInfos(String zookeeperQuorum, String zookeeperClientPort,
                                               String hBaseRootDir, String snapshotName) throws IOException {
    try {
        Configuration conf = Utils.getHadoopConf(zookeeperQuorum, zookeeperClientPort);
        Path root = new Path(hBaseRootDir);
        FileSystem fs = FileSystem.get(conf);
        Path snapshotDir = SnapshotDescriptionUtils.getCompletedSnapshotDir(snapshotName, root);
        HBaseProtos.SnapshotDescription snapshotDesc = SnapshotDescriptionUtils.readSnapshotInfo(fs, snapshotDir);
        SnapshotManifest manifest = SnapshotManifest.open(conf, fs, snapshotDir, snapshotDesc);
        return Utils.getRegionInfosFromManifest(manifest);
    } catch (IOException ex) {
        logger.error("get region info error: " + ex.getMessage(), ex);
        throw ex;
    }
}
 

@Override
public List<HRegionLocation> getRegionBoundaries(StatementContext context, byte[] tableName) throws SQLException {
	String snapshotName;
	Configuration conf = context.getConnection().getQueryServices().getConfiguration();
	if((snapshotName = getSnapshotName(conf)) != null) {
		try {
			Path rootDir = new Path(conf.get(HConstants.HBASE_DIR));
			FileSystem fs = rootDir.getFileSystem(conf);
			Path snapshotDir = SnapshotDescriptionUtils.getCompletedSnapshotDir(snapshotName, rootDir);
			SnapshotDescription snapshotDescription = SnapshotDescriptionUtils.readSnapshotInfo(fs, snapshotDir);
			SnapshotManifest manifest = SnapshotManifest.open(conf, fs, snapshotDir, snapshotDescription);
			return getRegionLocationsFromManifest(manifest);
		}
		catch (Exception e) {
			throw new RuntimeException(e);
		}
	}
	else {
		return context.getConnection().getQueryServices().getAllTableRegions(tableName);
	}
}
 

public static List<RegionInfo> getRegionInfosFromManifest(SnapshotManifest manifest) {
  List<SnapshotRegionManifest> regionManifests = manifest.getRegionManifests();
  if (regionManifests == null) {
    throw new IllegalArgumentException("Snapshot seems empty");
  }

  List<RegionInfo> regionInfos = Lists.newArrayListWithCapacity(regionManifests.size());

  for (SnapshotRegionManifest regionManifest : regionManifests) {
    RegionInfo hri = ProtobufUtil.toRegionInfo(regionManifest.getRegionInfo());
    if (hri.isOffline() && (hri.isSplit() || hri.isSplitParent())) {
      continue;
    }
    regionInfos.add(hri);
  }
  return regionInfos;
}
 

private Set<String> getFilesReferencedBySnapshot(String snapshotName) throws IOException {
  HashSet<String> files = new HashSet<>();
  Path snapshotDir = SnapshotDescriptionUtils.getCompletedSnapshotDir(
      snapshotName, CommonFSUtils.getRootDir(conf));
  SnapshotProtos.SnapshotDescription sd = SnapshotDescriptionUtils.readSnapshotInfo(
      fs, snapshotDir);
  SnapshotManifest manifest = SnapshotManifest.open(conf, fs, snapshotDir, sd);
  // For each region referenced by the snapshot
  for (SnapshotRegionManifest rm : manifest.getRegionManifests()) {
    // For each column family in this region
    for (FamilyFiles ff : rm.getFamilyFilesList()) {
      // And each store file in that family
      for (StoreFile sf : ff.getStoreFilesList()) {
        files.add(sf.getName());
      }
    }
  }
  return files;
}
 

/**
 * Action before cloning from snapshot.
 * @param env MasterProcedureEnv
 * @throws IOException
 * @throws InterruptedException
 */
private void preCloneSnapshot(final MasterProcedureEnv env)
    throws IOException, InterruptedException {
  if (!getTableName().isSystemTable()) {
    // Check and update namespace quota
    final MasterFileSystem mfs = env.getMasterServices().getMasterFileSystem();

    SnapshotManifest manifest = SnapshotManifest.open(
      env.getMasterConfiguration(),
      mfs.getFileSystem(),
      SnapshotDescriptionUtils.getCompletedSnapshotDir(snapshot, mfs.getRootDir()),
      snapshot);

    ProcedureSyncWait.getMasterQuotaManager(env)
      .checkNamespaceTableAndRegionQuota(getTableName(), manifest.getRegionManifestsMap().size());
  }

  final MasterCoprocessorHost cpHost = env.getMasterCoprocessorHost();
  if (cpHost != null) {
    cpHost.preCreateTableAction(tableDescriptor, null, getUser());
  }
}
 

public static List<HRegionInfo> getRegionInfosFromManifest(SnapshotManifest manifest) {
    List<SnapshotProtos.SnapshotRegionManifest> regionManifests = manifest.getRegionManifests();
    if (regionManifests == null) {
        throw new IllegalArgumentException("Snapshot seems empty");
    }

    List<HRegionInfo> regionInfos = Lists.newArrayListWithCapacity(regionManifests.size());

    for (SnapshotProtos.SnapshotRegionManifest regionManifest : regionManifests) {
        HRegionInfo hri = HRegionInfo.convert(regionManifest.getRegionInfo());
        if (hri.isOffline() && (hri.isSplit() || hri.isSplitParent())) {
            continue;
        }
        regionInfos.add(hri);
    }
    return regionInfos;
}
 

/**
 * Get table descriptor
 * @param tableName is the table backed up
 * @return {@link TableDescriptor} saved in backup image of the table
 */
TableDescriptor getTableDesc(TableName tableName) throws IOException {
  Path tableInfoPath = this.getTableInfoPath(tableName);
  SnapshotDescription desc = SnapshotDescriptionUtils.readSnapshotInfo(fs, tableInfoPath);
  SnapshotManifest manifest = SnapshotManifest.open(conf, fs, tableInfoPath, desc);
  TableDescriptor tableDescriptor = manifest.getTableDescriptor();
  if (!tableDescriptor.getTableName().equals(tableName)) {
    LOG.error("couldn't find Table Desc for table: " + tableName + " under tableInfoPath: "
            + tableInfoPath.toString());
    LOG.error("tableDescriptor.getNameAsString() = "
            + tableDescriptor.getTableName().getNameAsString());
    throw new FileNotFoundException("couldn't find Table Desc for table: " + tableName
        + " under tableInfoPath: " + tableInfoPath.toString());
  }
  return tableDescriptor;
}
 

private void openWithoutRestoringSnapshot() throws IOException {
  Path snapshotDir = SnapshotDescriptionUtils.getCompletedSnapshotDir(snapshotName, rootDir);
  SnapshotProtos.SnapshotDescription snapshotDesc =
      SnapshotDescriptionUtils.readSnapshotInfo(fs, snapshotDir);

  SnapshotManifest manifest = SnapshotManifest.open(conf, fs, snapshotDir, snapshotDesc);
  List<SnapshotRegionManifest> regionManifests = manifest.getRegionManifests();
  if (regionManifests == null) {
    throw new IllegalArgumentException("Snapshot seems empty, snapshotName: " + snapshotName);
  }

  regions = new ArrayList<>(regionManifests.size());
  regionManifests.stream().map(r -> ProtobufUtil.toRegionInfo(r.getRegionInfo()))
    .filter(this::isValidRegion).sorted().forEach(r -> regions.add(r));
  htd = manifest.getTableDescriptor();
}
 

/**
 * Extracts the names of the store files referenced by this snapshot which satisfy the given
 * predicate (the predicate returns {@code true}).
 */
Set<StoreFileReference> getStoreFilesFromSnapshot(
    SnapshotManifest manifest, Predicate<String> filter) {
  Set<StoreFileReference> references = new HashSet<>();
  // For each region referenced by the snapshot
  for (SnapshotRegionManifest rm : manifest.getRegionManifests()) {
    StoreFileReference regionReference = new StoreFileReference(
        ProtobufUtil.toRegionInfo(rm.getRegionInfo()).getEncodedName());

    // For each column family in this region
    for (FamilyFiles ff : rm.getFamilyFilesList()) {
      final String familyName = ff.getFamilyName().toStringUtf8();
      // And each store file in that family
      for (StoreFile sf : ff.getStoreFilesList()) {
        String storeFileName = sf.getName();
        // A snapshot only "inherits" a files size if it uniquely refers to it (no table
        // and no other snapshot references it).
        if (filter.test(storeFileName)) {
          regionReference.addFamilyStoreFile(familyName, storeFileName);
        }
      }
    }
    // Only add this Region reference if we retained any files.
    if (!regionReference.getFamilyToFilesMapping().isEmpty()) {
      references.add(regionReference);
    }
  }
  return references;
}
 

/**
 * Return the list of splits extracted from the scans/snapshots pushed to conf by
 * {@link
 * #setInput(org.apache.hadoop.conf.Configuration, java.util.Map, org.apache.hadoop.fs.Path)}
 *
 * @param conf Configuration to determine splits from
 * @return Return the list of splits extracted from the scans/snapshots pushed to conf
 * @throws IOException
 */
public List<TableSnapshotInputFormatImpl.InputSplit> getSplits(Configuration conf)
    throws IOException {
  Path rootDir = CommonFSUtils.getRootDir(conf);
  FileSystem fs = rootDir.getFileSystem(conf);

  List<TableSnapshotInputFormatImpl.InputSplit> rtn = Lists.newArrayList();

  Map<String, Collection<Scan>> snapshotsToScans = getSnapshotsToScans(conf);
  Map<String, Path> snapshotsToRestoreDirs = getSnapshotDirs(conf);
  for (Map.Entry<String, Collection<Scan>> entry : snapshotsToScans.entrySet()) {
    String snapshotName = entry.getKey();

    Path restoreDir = snapshotsToRestoreDirs.get(snapshotName);

    SnapshotManifest manifest =
        TableSnapshotInputFormatImpl.getSnapshotManifest(conf, snapshotName, rootDir, fs);
    List<RegionInfo> regionInfos =
        TableSnapshotInputFormatImpl.getRegionInfosFromManifest(manifest);

    for (Scan scan : entry.getValue()) {
      List<TableSnapshotInputFormatImpl.InputSplit> splits =
          TableSnapshotInputFormatImpl.getSplits(scan, manifest, regionInfos, restoreDir, conf);
      rtn.addAll(splits);
    }
  }
  return rtn;
}
 

/**
 * Check that the table descriptor for the snapshot is a valid table descriptor
 * @param manifest snapshot manifest to inspect
 */
private void verifyTableInfo(final SnapshotManifest manifest) throws IOException {
  TableDescriptor htd = manifest.getTableDescriptor();
  if (htd == null) {
    throw new CorruptedSnapshotException("Missing Table Descriptor",
      ProtobufUtil.createSnapshotDesc(snapshot));
  }

  if (!htd.getTableName().getNameAsString().equals(snapshot.getTable())) {
    throw new CorruptedSnapshotException(
        "Invalid Table Descriptor. Expected " + snapshot.getTable() + " name, got "
            + htd.getTableName().getNameAsString(), ProtobufUtil.createSnapshotDesc(snapshot));
  }
}
 

/**
 * Verify that the snapshot in the directory is a valid snapshot
 * @param snapshotDir snapshot directory to check
 * @param snapshotServers {@link org.apache.hadoop.hbase.ServerName} of the servers
 *        that are involved in the snapshot
 * @throws CorruptedSnapshotException if the snapshot is invalid
 * @throws IOException if there is an unexpected connection issue to the filesystem
 */
public void verifySnapshot(Path snapshotDir, Set<String> snapshotServers)
    throws CorruptedSnapshotException, IOException {
  SnapshotManifest manifest = SnapshotManifest.open(services.getConfiguration(), workingDirFs,
                                                    snapshotDir, snapshot);
  // verify snapshot info matches
  verifySnapshotDescription(snapshotDir);

  // check that tableinfo is a valid table description
  verifyTableInfo(manifest);

  // check that each region is valid
  verifyRegions(manifest);
}
 

/**
 * Execute the on-disk Restore
 * @param env MasterProcedureEnv
 * @throws IOException
 **/
private void restoreSnapshot(final MasterProcedureEnv env) throws IOException {
  MasterFileSystem fileSystemManager = env.getMasterServices().getMasterFileSystem();
  FileSystem fs = fileSystemManager.getFileSystem();
  Path rootDir = fileSystemManager.getRootDir();
  final ForeignExceptionDispatcher monitorException = new ForeignExceptionDispatcher();

  LOG.info("Starting restore snapshot=" + ClientSnapshotDescriptionUtils.toString(snapshot));
  try {
    Path snapshotDir = SnapshotDescriptionUtils.getCompletedSnapshotDir(snapshot, rootDir);
    SnapshotManifest manifest = SnapshotManifest.open(
      env.getMasterServices().getConfiguration(), fs, snapshotDir, snapshot);
    RestoreSnapshotHelper restoreHelper = new RestoreSnapshotHelper(
      env.getMasterServices().getConfiguration(),
      fs,
      manifest,
      modifiedTableDescriptor,
      rootDir,
      monitorException,
      getMonitorStatus());

    RestoreSnapshotHelper.RestoreMetaChanges metaChanges = restoreHelper.restoreHdfsRegions();
    regionsToRestore = metaChanges.getRegionsToRestore();
    regionsToRemove = metaChanges.getRegionsToRemove();
    regionsToAdd = metaChanges.getRegionsToAdd();
    parentsToChildrenPairMap = metaChanges.getParentToChildrenPairMap();
  } catch (IOException e) {
    String msg = "restore snapshot=" + ClientSnapshotDescriptionUtils.toString(snapshot)
      + " failed in on-disk restore. Try re-running the restore command.";
    LOG.error(msg, e);
    monitorException.receive(
      new ForeignException(env.getMasterServices().getServerName().toString(), e));
    throw new IOException(msg, e);
  }
}
 

/**
 * Action before any real action of restoring from snapshot.
 * @param env MasterProcedureEnv
 * @throws IOException
 */
private void prepareRestore(final MasterProcedureEnv env) throws IOException {
  final TableName tableName = getTableName();
  // Checks whether the table exists
  if (!MetaTableAccessor.tableExists(env.getMasterServices().getConnection(), tableName)) {
    throw new TableNotFoundException(tableName);
  }

  // Check whether table is disabled.
  env.getMasterServices().checkTableModifiable(tableName);

  // Check that we have at least 1 CF
  if (modifiedTableDescriptor.getColumnFamilyCount() == 0) {
    throw new DoNotRetryIOException("Table " + getTableName().toString() +
      " should have at least one column family.");
  }

  if (!getTableName().isSystemTable()) {
    // Table already exist. Check and update the region quota for this table namespace.
    final MasterFileSystem mfs = env.getMasterServices().getMasterFileSystem();
    SnapshotManifest manifest = SnapshotManifest.open(
      env.getMasterConfiguration(),
      mfs.getFileSystem(),
      SnapshotDescriptionUtils.getCompletedSnapshotDir(snapshot, mfs.getRootDir()),
      snapshot);
    int snapshotRegionCount = manifest.getRegionManifestsMap().size();
    int tableRegionCount =
        ProcedureSyncWait.getMasterQuotaManager(env).getRegionCountOfTable(tableName);

    if (snapshotRegionCount > 0 && tableRegionCount != snapshotRegionCount) {
      ProcedureSyncWait.getMasterQuotaManager(env).checkAndUpdateNamespaceRegionQuota(
        tableName, snapshotRegionCount);
    }
  }
}
 

/**
 * For the given snapshot, find all files which this {@code snapshotName} references. After a file
 * is found to be referenced by the snapshot, it is removed from {@code filesToUpdate} and
 * {@code snapshotSizeChanges} is updated in concert.
 *
 * @param snapshotName The snapshot to check
 * @param filesToUpdate A mapping of archived files to their size
 * @param snapshotSizeChanges A mapping of snapshots and their change in size
 */
void bucketFilesToSnapshot(
    String snapshotName, Map<String,Long> filesToUpdate, Map<String,Long> snapshotSizeChanges)
        throws IOException {
  // A quick check to avoid doing work if the caller unnecessarily invoked this method.
  if (filesToUpdate.isEmpty()) {
    return;
  }

  Path snapshotDir = SnapshotDescriptionUtils.getCompletedSnapshotDir(
      snapshotName, CommonFSUtils.getRootDir(conf));
  SnapshotDescription sd = SnapshotDescriptionUtils.readSnapshotInfo(fs, snapshotDir);
  SnapshotManifest manifest = SnapshotManifest.open(conf, fs, snapshotDir, sd);
  // For each region referenced by the snapshot
  for (SnapshotRegionManifest rm : manifest.getRegionManifests()) {
    // For each column family in this region
    for (FamilyFiles ff : rm.getFamilyFilesList()) {
      // And each store file in that family
      for (StoreFile sf : ff.getStoreFilesList()) {
        Long valueOrNull = filesToUpdate.remove(sf.getName());
        if (valueOrNull != null) {
          // This storefile was recently archived, we should update this snapshot with its size
          snapshotSizeChanges.merge(snapshotName, valueOrNull, Long::sum);
        }
        // Short-circuit, if we have no more files that were archived, we don't need to iterate
        // over the rest of the snapshot.
        if (filesToUpdate.isEmpty()) {
          return;
        }
      }
    }
  }
}
 

/**
 * Check that all the regions in the snapshot are valid, and accounted for.
 * @param manifest snapshot manifest to inspect
 * @throws IOException if we can't reach hbase:meta or read the files from the FS
 */
private void verifyRegions(final SnapshotManifest manifest) throws IOException {
  List<RegionInfo> regions;
  if (TableName.META_TABLE_NAME.equals(tableName)) {
    regions = MetaTableLocator.getMetaRegions(services.getZooKeeper());
  } else {
    regions = MetaTableAccessor.getTableRegions(services.getConnection(), tableName);
  }
  // Remove the non-default regions
  RegionReplicaUtil.removeNonDefaultRegions(regions);

  Map<String, SnapshotRegionManifest> regionManifests = manifest.getRegionManifestsMap();
  if (regionManifests == null) {
    String msg = "Snapshot " + ClientSnapshotDescriptionUtils.toString(snapshot) + " looks empty";
    LOG.error(msg);
    throw new CorruptedSnapshotException(msg);
  }

  String errorMsg = "";
  boolean hasMobStore = false;
  // the mob region is a dummy region, it's not a real region in HBase.
  // the mob region has a special name, it could be found by the region name.
  if (regionManifests.get(MobUtils.getMobRegionInfo(tableName).getEncodedName()) != null) {
    hasMobStore = true;
  }
  int realRegionCount = hasMobStore ? regionManifests.size() - 1 : regionManifests.size();
  if (realRegionCount != regions.size()) {
    errorMsg = "Regions moved during the snapshot '" +
                 ClientSnapshotDescriptionUtils.toString(snapshot) + "'. expected=" +
                 regions.size() + " snapshotted=" + realRegionCount + ".";
    LOG.error(errorMsg);
  }

  // Verify RegionInfo
  for (RegionInfo region : regions) {
    SnapshotRegionManifest regionManifest = regionManifests.get(region.getEncodedName());
    if (regionManifest == null) {
      // could happen due to a move or split race.
      String mesg = " No snapshot region directory found for region:" + region;
      if (errorMsg.isEmpty()) errorMsg = mesg;
      LOG.error(mesg);
      continue;
    }

    verifyRegionInfo(region, regionManifest);
  }

  if (!errorMsg.isEmpty()) {
    throw new CorruptedSnapshotException(errorMsg);
  }

  // Verify Snapshot HFiles
  // Requires the root directory file system as HFiles are stored in the root directory
  SnapshotReferenceUtil.verifySnapshot(services.getConfiguration(),
    CommonFSUtils.getRootDirFileSystem(services.getConfiguration()), manifest);
}
 

/**
 * Restore or Clone the specified snapshot
 * @param reqSnapshot
 * @param nonceKey unique identifier to prevent duplicated RPC
 * @throws IOException
 */
public long restoreOrCloneSnapshot(final SnapshotDescription reqSnapshot, final NonceKey nonceKey,
    final boolean restoreAcl) throws IOException {
  FileSystem fs = master.getMasterFileSystem().getFileSystem();
  Path snapshotDir = SnapshotDescriptionUtils.getCompletedSnapshotDir(reqSnapshot, rootDir);

  // check if the snapshot exists
  if (!fs.exists(snapshotDir)) {
    LOG.error("A Snapshot named '" + reqSnapshot.getName() + "' does not exist.");
    throw new SnapshotDoesNotExistException(
      ProtobufUtil.createSnapshotDesc(reqSnapshot));
  }

  // Get snapshot info from file system. The reqSnapshot is a "fake" snapshotInfo with
  // just the snapshot "name" and table name to restore. It does not contains the "real" snapshot
  // information.
  SnapshotDescription snapshot = SnapshotDescriptionUtils.readSnapshotInfo(fs, snapshotDir);
  SnapshotManifest manifest = SnapshotManifest.open(master.getConfiguration(), fs,
      snapshotDir, snapshot);
  TableDescriptor snapshotTableDesc = manifest.getTableDescriptor();
  TableName tableName = TableName.valueOf(reqSnapshot.getTable());

  // sanity check the new table descriptor
  TableDescriptorChecker.sanityCheck(master.getConfiguration(), snapshotTableDesc);

  // stop tracking "abandoned" handlers
  cleanupSentinels();

  // Verify snapshot validity
  SnapshotReferenceUtil.verifySnapshot(master.getConfiguration(), fs, manifest);

  // Execute the restore/clone operation
  long procId;
  if (MetaTableAccessor.tableExists(master.getConnection(), tableName)) {
    procId = restoreSnapshot(reqSnapshot, tableName, snapshot, snapshotTableDesc, nonceKey,
      restoreAcl);
  } else {
    procId =
        cloneSnapshot(reqSnapshot, tableName, snapshot, snapshotTableDesc, nonceKey, restoreAcl);
  }
  return procId;
}
 

@Override
public void snapshotRegions(List<Pair<RegionInfo, ServerName>> regionsAndLocations)
    throws IOException, KeeperException {
  try {
    // 1. get all the regions hosting this table.

    // extract each pair to separate lists
    Set<RegionInfo> regions = new HashSet<>();
    for (Pair<RegionInfo, ServerName> p : regionsAndLocations) {
      // Don't include non-default regions
      RegionInfo hri = p.getFirst();
      if (RegionReplicaUtil.isDefaultReplica(hri)) {
        regions.add(hri);
      }
    }
    // handle the mob files if any.
    boolean mobEnabled = MobUtils.hasMobColumns(htd);
    if (mobEnabled) {
      // snapshot the mob files as a offline region.
      RegionInfo mobRegionInfo = MobUtils.getMobRegionInfo(htd.getTableName());
      regions.add(mobRegionInfo);
    }

    // 2. for each region, write all the info to disk
    String msg = "Starting to write region info and WALs for regions for offline snapshot:"
        + ClientSnapshotDescriptionUtils.toString(snapshot);
    LOG.info(msg);
    status.setStatus(msg);

    ThreadPoolExecutor exec = SnapshotManifest.createExecutor(conf, "DisabledTableSnapshot");
    try {
      ModifyRegionUtils.editRegions(exec, regions, new ModifyRegionUtils.RegionEditTask() {
        @Override
        public void editRegion(final RegionInfo regionInfo) throws IOException {
          snapshotManifest.addRegion(CommonFSUtils.getTableDir(rootDir, snapshotTable),
            regionInfo);
        }
      });
    } finally {
      exec.shutdown();
    }
  } catch (Exception e) {
    // make sure we capture the exception to propagate back to the client later
    String reason = "Failed snapshot " + ClientSnapshotDescriptionUtils.toString(snapshot)
        + " due to exception:" + e.getMessage();
    ForeignException ee = new ForeignException(reason, e);
    monitor.receive(ee);
    status.abort("Snapshot of table: "+ snapshotTable + " failed because " + e.getMessage());
  } finally {
    LOG.debug("Marking snapshot" + ClientSnapshotDescriptionUtils.toString(snapshot)
        + " as finished.");
  }
}
 

private void createAndRestoreTable(Connection conn, TableName tableName, TableName newTableName,
    Path tableBackupPath, boolean truncateIfExists, String lastIncrBackupId) throws IOException {
  if (newTableName == null) {
    newTableName = tableName;
  }
  FileSystem fileSys = tableBackupPath.getFileSystem(this.conf);

  // get table descriptor first
  TableDescriptor tableDescriptor = getTableDescriptor(fileSys, tableName, lastIncrBackupId);
  if (tableDescriptor != null) {
    LOG.debug("Retrieved descriptor: " + tableDescriptor + " thru " + lastIncrBackupId);
  }

  if (tableDescriptor == null) {
    Path tableSnapshotPath = getTableSnapshotPath(backupRootPath, tableName, backupId);
    if (fileSys.exists(tableSnapshotPath)) {
      // snapshot path exist means the backup path is in HDFS
      // check whether snapshot dir already recorded for target table
      if (snapshotMap.get(tableName) != null) {
        SnapshotDescription desc =
            SnapshotDescriptionUtils.readSnapshotInfo(fileSys, tableSnapshotPath);
        SnapshotManifest manifest = SnapshotManifest.open(conf, fileSys, tableSnapshotPath, desc);
        tableDescriptor = manifest.getTableDescriptor();
      } else {
        tableDescriptor = getTableDesc(tableName);
        snapshotMap.put(tableName, getTableInfoPath(tableName));
      }
      if (tableDescriptor == null) {
        LOG.debug("Found no table descriptor in the snapshot dir, previous schema would be lost");
      }
    } else {
      throw new IOException("Table snapshot directory: " +
          tableSnapshotPath + " does not exist.");
    }
  }

  Path tableArchivePath = getTableArchivePath(tableName);
  if (tableArchivePath == null) {
    if (tableDescriptor != null) {
      // find table descriptor but no archive dir means the table is empty, create table and exit
      if (LOG.isDebugEnabled()) {
        LOG.debug("find table descriptor but no archive dir for table " + tableName
            + ", will only create table");
      }
      tableDescriptor = TableDescriptorBuilder.copy(newTableName, tableDescriptor);
      checkAndCreateTable(conn, tableBackupPath, tableName, newTableName, null, tableDescriptor,
        truncateIfExists);
      return;
    } else {
      throw new IllegalStateException("Cannot restore hbase table because directory '"
          + " tableArchivePath is null.");
    }
  }

  if (tableDescriptor == null) {
    tableDescriptor = TableDescriptorBuilder.newBuilder(newTableName).build();
  } else {
    tableDescriptor = TableDescriptorBuilder.copy(newTableName, tableDescriptor);
  }

  // record all region dirs:
  // load all files in dir
  try {
    ArrayList<Path> regionPathList = getRegionList(tableName);

    // should only try to create the table with all region informations, so we could pre-split
    // the regions in fine grain
    checkAndCreateTable(conn, tableBackupPath, tableName, newTableName, regionPathList,
      tableDescriptor, truncateIfExists);
    RestoreJob restoreService = BackupRestoreFactory.getRestoreJob(conf);
    Path[] paths = new Path[regionPathList.size()];
    regionPathList.toArray(paths);
    restoreService.run(paths, new TableName[]{tableName}, new TableName[] {newTableName}, true);

  } catch (Exception e) {
    LOG.error(e.toString(), e);
    throw new IllegalStateException("Cannot restore hbase table", e);
  }
}
 

public static List<InputSplit> getSplits(Configuration conf) throws IOException {
  String snapshotName = getSnapshotName(conf);

  Path rootDir = CommonFSUtils.getRootDir(conf);
  FileSystem fs = rootDir.getFileSystem(conf);

  SnapshotManifest manifest = getSnapshotManifest(conf, snapshotName, rootDir, fs);

  List<RegionInfo> regionInfos = getRegionInfosFromManifest(manifest);

  // TODO: mapred does not support scan as input API. Work around for now.
  Scan scan = extractScanFromConf(conf);
  // the temp dir where the snapshot is restored
  Path restoreDir = new Path(conf.get(RESTORE_DIR_KEY));

  RegionSplitter.SplitAlgorithm splitAlgo = getSplitAlgo(conf);

  int numSplits = conf.getInt(NUM_SPLITS_PER_REGION, 1);

  return getSplits(scan, manifest, regionInfos, restoreDir, conf, splitAlgo, numSplits);
}
 

public static SnapshotManifest getSnapshotManifest(Configuration conf, String snapshotName,
    Path rootDir, FileSystem fs) throws IOException {
  Path snapshotDir = SnapshotDescriptionUtils.getCompletedSnapshotDir(snapshotName, rootDir);
  SnapshotDescription snapshotDesc = SnapshotDescriptionUtils.readSnapshotInfo(fs, snapshotDir);
  return SnapshotManifest.open(conf, fs, snapshotDir, snapshotDesc);
}
 

public static List<InputSplit> getSplits(Scan scan, SnapshotManifest manifest,
    List<RegionInfo> regionManifests, Path restoreDir, Configuration conf) throws IOException {
  return getSplits(scan, manifest, regionManifests, restoreDir, conf, null, 1);
}