/**
* 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.datanode.fsdataset;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.util.List;
import java.util.Map;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hdfs.DFSConfigKeys;
import org.apache.hadoop.hdfs.protocol.Block;
import org.apache.hadoop.hdfs.protocol.BlockListAsLongs;
import org.apache.hadoop.hdfs.protocol.BlockLocalPathInfo;
import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
import org.apache.hadoop.hdfs.protocol.HdfsBlocksMetadata;
import org.apache.hadoop.hdfs.server.datanode.DataNode;
import org.apache.hadoop.hdfs.server.datanode.DataStorage;
import org.apache.hadoop.hdfs.server.datanode.FinalizedReplica;
import org.apache.hadoop.hdfs.server.datanode.Replica;
import org.apache.hadoop.hdfs.server.datanode.ReplicaInPipelineInterface;
import org.apache.hadoop.hdfs.server.datanode.fsdataset.impl.FsDatasetFactory;
import org.apache.hadoop.hdfs.server.datanode.metrics.FSDatasetMBean;
import org.apache.hadoop.hdfs.server.protocol.BlockRecoveryCommand.RecoveringBlock;
import org.apache.hadoop.hdfs.server.protocol.DatanodeStorage;
import org.apache.hadoop.hdfs.server.protocol.ReplicaRecoveryInfo;
import org.apache.hadoop.hdfs.server.protocol.StorageReport;
import org.apache.hadoop.util.DiskChecker.DiskErrorException;
import org.apache.hadoop.util.ReflectionUtils;
/**
* This is a service provider interface for the underlying storage that
* stores replicas for a data node.
* The default implementation stores replicas on local drives.
*/
@InterfaceAudience.Private
public interface FsDatasetSpi<V extends FsVolumeSpi> extends FSDatasetMBean {
/**
* A factory for creating {@link FsDatasetSpi} objects.
*/
public static abstract class Factory<D extends FsDatasetSpi<?>> {
/** @return the configured factory. */
public static Factory<?> getFactory(Configuration conf) {
@SuppressWarnings("rawtypes")
final Class<? extends Factory> clazz = conf.getClass(
DFSConfigKeys.DFS_DATANODE_FSDATASET_FACTORY_KEY,
FsDatasetFactory.class,
Factory.class);
return ReflectionUtils.newInstance(clazz, conf);
}
/** Create a new object. */
public abstract D newInstance(DataNode datanode, DataStorage storage,
Configuration conf) throws IOException;
/** Does the factory create simulated objects? */
public boolean isSimulated() {
return false;
}
}
/**
* Create rolling logs.
*
* @param prefix the prefix of the log names.
* @return rolling logs
*/
public RollingLogs createRollingLogs(String bpid, String prefix
) throws IOException;
/** @return a list of volumes. */
public List<V> getVolumes();
/** @return a storage with the given storage ID */
public DatanodeStorage getStorage(final String storageUuid);
/** @return one or more storage reports for attached volumes. */
public StorageReport[] getStorageReports(String bpid)
throws IOException;
/** @return the volume that contains a replica of the block. */
public V getVolume(ExtendedBlock b);
/** @return a volume information map (name => info). */
public Map<String, Object> getVolumeInfoMap();
/** @return a list of finalized blocks for the given block pool. */
public List<FinalizedReplica> getFinalizedBlocks(String bpid);
/**
* Check whether the in-memory block record matches the block on the disk,
* and, in case that they are not matched, update the record or mark it
* as corrupted.
*/
public void checkAndUpdate(String bpid, long blockId, File diskFile,
File diskMetaFile, FsVolumeSpi vol);
/**
* @param b - the block
* @return a stream if the meta-data of the block exists;
* otherwise, return null.
* @throws IOException
*/
public LengthInputStream getMetaDataInputStream(ExtendedBlock b
) throws IOException;
/**
* Returns the specified block's on-disk length (excluding metadata)
* @param b
* @return the specified block's on-disk length (excluding metadta)
* @throws IOException
*/
public long getLength(ExtendedBlock b) throws IOException;
/**
* Get reference to the replica meta info in the replicasMap.
* To be called from methods that are synchronized on {@link FSDataset}
* @param blockId
* @return replica from the replicas map
*/
@Deprecated
public Replica getReplica(String bpid, long blockId);
/**
* @return replica meta information
*/
public String getReplicaString(String bpid, long blockId);
/**
* @return the generation stamp stored with the block.
*/
public Block getStoredBlock(String bpid, long blkid) throws IOException;
/**
* Returns an input stream at specified offset of the specified block
* @param b
* @param seekOffset
* @return an input stream to read the contents of the specified block,
* starting at the offset
* @throws IOException
*/
public InputStream getBlockInputStream(ExtendedBlock b, long seekOffset)
throws IOException;
/**
* Returns an input stream at specified offset of the specified block
* The block is still in the tmp directory and is not finalized
* @param b
* @param blkoff
* @param ckoff
* @return an input stream to read the contents of the specified block,
* starting at the offset
* @throws IOException
*/
public ReplicaInputStreams getTmpInputStreams(ExtendedBlock b, long blkoff,
long ckoff) throws IOException;
/**
* Creates a temporary replica and returns the meta information of the replica
*
* @param b block
* @return the meta info of the replica which is being written to
* @throws IOException if an error occurs
*/
public ReplicaInPipelineInterface createTemporary(ExtendedBlock b
) throws IOException;
/**
* Creates a RBW replica and returns the meta info of the replica
*
* @param b block
* @return the meta info of the replica which is being written to
* @throws IOException if an error occurs
*/
public ReplicaInPipelineInterface createRbw(ExtendedBlock b
) throws IOException;
/**
* Recovers a RBW replica and returns the meta info of the replica
*
* @param b block
* @param newGS the new generation stamp for the replica
* @param minBytesRcvd the minimum number of bytes that the replica could have
* @param maxBytesRcvd the maximum number of bytes that the replica could have
* @return the meta info of the replica which is being written to
* @throws IOException if an error occurs
*/
public ReplicaInPipelineInterface recoverRbw(ExtendedBlock b,
long newGS, long minBytesRcvd, long maxBytesRcvd) throws IOException;
/**
* Covert a temporary replica to a RBW.
* @param temporary the temporary replica being converted
* @return the result RBW
*/
public ReplicaInPipelineInterface convertTemporaryToRbw(
ExtendedBlock temporary) throws IOException;
/**
* Append to a finalized replica and returns the meta info of the replica
*
* @param b block
* @param newGS the new generation stamp for the replica
* @param expectedBlockLen the number of bytes the replica is expected to have
* @return the meata info of the replica which is being written to
* @throws IOException
*/
public ReplicaInPipelineInterface append(ExtendedBlock b, long newGS,
long expectedBlockLen) throws IOException;
/**
* Recover a failed append to a finalized replica
* and returns the meta info of the replica
*
* @param b block
* @param newGS the new generation stamp for the replica
* @param expectedBlockLen the number of bytes the replica is expected to have
* @return the meta info of the replica which is being written to
* @throws IOException
*/
public ReplicaInPipelineInterface recoverAppend(ExtendedBlock b, long newGS,
long expectedBlockLen) throws IOException;
/**
* Recover a failed pipeline close
* It bumps the replica's generation stamp and finalize it if RBW replica
*
* @param b block
* @param newGS the new generation stamp for the replica
* @param expectedBlockLen the number of bytes the replica is expected to have
* @return the storage uuid of the replica.
* @throws IOException
*/
public String recoverClose(ExtendedBlock b, long newGS, long expectedBlockLen
) throws IOException;
/**
* Finalizes the block previously opened for writing using writeToBlock.
* The block size is what is in the parameter b and it must match the amount
* of data written
* @param b
* @throws IOException
*/
public void finalizeBlock(ExtendedBlock b) throws IOException;
/**
* Unfinalizes the block previously opened for writing using writeToBlock.
* The temporary file associated with this block is deleted.
* @param b
* @throws IOException
*/
public void unfinalizeBlock(ExtendedBlock b) throws IOException;
/**
* Returns one block report per volume.
* @param bpid Block Pool Id
* @return - a map of DatanodeStorage to block report for the volume.
*/
public Map<DatanodeStorage, BlockListAsLongs> getBlockReports(String bpid);
/**
* Returns the cache report - the full list of cached block IDs of a
* block pool.
* @param bpid Block Pool Id
* @return the cache report - the full list of cached block IDs.
*/
public List<Long> getCacheReport(String bpid);
/** Does the dataset contain the block? */
public boolean contains(ExtendedBlock block);
/**
* Is the block valid?
* @param b
* @return - true if the specified block is valid
*/
public boolean isValidBlock(ExtendedBlock b);
/**
* Is the block a valid RBW?
* @param b
* @return - true if the specified block is a valid RBW
*/
public boolean isValidRbw(ExtendedBlock b);
/**
* Invalidates the specified blocks
* @param bpid Block pool Id
* @param invalidBlks - the blocks to be invalidated
* @throws IOException
*/
public void invalidate(String bpid, Block invalidBlks[]) throws IOException;
/**
* Caches the specified blocks
* @param bpid Block pool id
* @param blockIds - block ids to cache
*/
public void cache(String bpid, long[] blockIds);
/**
* Uncaches the specified blocks
* @param bpid Block pool id
* @param blockIds - blocks ids to uncache
*/
public void uncache(String bpid, long[] blockIds);
/**
* Determine if the specified block is cached.
* @param bpid Block pool id
* @param blockIds - block id
* @returns true if the block is cached
*/
public boolean isCached(String bpid, long blockId);
/**
* Check if all the data directories are healthy
* @throws DiskErrorException
*/
public void checkDataDir() throws DiskErrorException;
/**
* Shutdown the FSDataset
*/
public void shutdown();
/**
* Sets the file pointer of the checksum stream so that the last checksum
* will be overwritten
* @param b block
* @param outs The streams for the data file and checksum file
* @param checksumSize number of bytes each checksum has
* @throws IOException
*/
public void adjustCrcChannelPosition(ExtendedBlock b,
ReplicaOutputStreams outs, int checksumSize) throws IOException;
/**
* Checks how many valid storage volumes there are in the DataNode.
* @return true if more than the minimum number of valid volumes are left
* in the FSDataSet.
*/
public boolean hasEnoughResource();
/**
* Get visible length of the specified replica.
*/
long getReplicaVisibleLength(final ExtendedBlock block) throws IOException;
/**
* Initialize a replica recovery.
* @return actual state of the replica on this data-node or
* null if data-node does not have the replica.
*/
public ReplicaRecoveryInfo initReplicaRecovery(RecoveringBlock rBlock
) throws IOException;
/**
* Update replica's generation stamp and length and finalize it.
* @return the ID of storage that stores the block
*/
public String updateReplicaUnderRecovery(ExtendedBlock oldBlock,
long recoveryId, long newLength) throws IOException;
/**
* add new block pool ID
* @param bpid Block pool Id
* @param conf Configuration
*/
public void addBlockPool(String bpid, Configuration conf) throws IOException;
/**
* Shutdown and remove the block pool from underlying storage.
* @param bpid Block pool Id to be removed
*/
public void shutdownBlockPool(String bpid) ;
/**
* Deletes the block pool directories. If force is false, directories are
* deleted only if no block files exist for the block pool. If force
* is true entire directory for the blockpool is deleted along with its
* contents.
* @param bpid BlockPool Id to be deleted.
* @param force If force is false, directories are deleted only if no
* block files exist for the block pool, otherwise entire
* directory for the blockpool is deleted along with its contents.
* @throws IOException
*/
public void deleteBlockPool(String bpid, boolean force) throws IOException;
/**
* Get {@link BlockLocalPathInfo} for the given block.
*/
public BlockLocalPathInfo getBlockLocalPathInfo(ExtendedBlock b
) throws IOException;
/**
* Get a {@link HdfsBlocksMetadata} corresponding to the list of blocks in
* <code>blocks</code>.
*
* @param bpid pool to query
* @param blockIds List of block ids for which to return metadata
* @return metadata Metadata for the list of blocks
* @throws IOException
*/
public HdfsBlocksMetadata getHdfsBlocksMetadata(String bpid,
long[] blockIds) throws IOException;
/**
* Enable 'trash' for the given dataset. When trash is enabled, files are
* moved to a separate trash directory instead of being deleted immediately.
* This can be useful for example during rolling upgrades.
*/
public void enableTrash(String bpid);
/**
* Restore trash
*/
public void restoreTrash(String bpid);
/**
* @return true when trash is enabled
*/
public boolean trashEnabled(String bpid);
}