org.apache.hadoop.hdfs.DistributedFileSystem Maven / Gradle / Ivy
/**
* 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;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.net.URI;
import java.util.ArrayList;
import java.util.EnumSet;
import java.util.List;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.BlockLocation;
import org.apache.hadoop.fs.ContentSummary;
import org.apache.hadoop.fs.CreateFlag;
import org.apache.hadoop.fs.BlockStorageLocation;
import org.apache.hadoop.fs.VolumeId;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.FsServerDefaults;
import org.apache.hadoop.fs.FsStatus;
import org.apache.hadoop.fs.LocatedFileStatus;
import org.apache.hadoop.fs.MD5MD5CRC32FileChecksum;
import org.apache.hadoop.fs.Options;
import org.apache.hadoop.fs.Options.ChecksumOpt;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.fs.PathFilter;
import org.apache.hadoop.fs.RemoteIterator;
import org.apache.hadoop.fs.permission.FsPermission;
import org.apache.hadoop.hdfs.client.HdfsDataInputStream;
import org.apache.hadoop.hdfs.client.HdfsDataOutputStream;
import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
import org.apache.hadoop.hdfs.protocol.DirectoryListing;
import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
import org.apache.hadoop.hdfs.protocol.HdfsConstants;
import org.apache.hadoop.hdfs.protocol.HdfsConstants.DatanodeReportType;
import org.apache.hadoop.hdfs.protocol.HdfsConstants.SafeModeAction;
import org.apache.hadoop.hdfs.protocol.HdfsConstants.UpgradeAction;
import org.apache.hadoop.hdfs.protocol.HdfsFileStatus;
import org.apache.hadoop.hdfs.protocol.HdfsLocatedFileStatus;
import org.apache.hadoop.hdfs.protocol.LocatedBlock;
import org.apache.hadoop.hdfs.security.token.block.InvalidBlockTokenException;
import org.apache.hadoop.hdfs.security.token.delegation.DelegationTokenIdentifier;
import org.apache.hadoop.hdfs.server.common.UpgradeStatusReport;
import org.apache.hadoop.hdfs.server.namenode.NameNode;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.net.NetUtils;
import org.apache.hadoop.security.AccessControlException;
import org.apache.hadoop.security.token.SecretManager.InvalidToken;
import org.apache.hadoop.security.token.Token;
import org.apache.hadoop.util.Progressable;
import com.google.common.annotations.VisibleForTesting;
/****************************************************************
* Implementation of the abstract FileSystem for the DFS system.
* This object is the way end-user code interacts with a Hadoop
* DistributedFileSystem.
*
*****************************************************************/
@InterfaceAudience.LimitedPrivate({ "MapReduce", "HBase" })
@InterfaceStability.Unstable
public class DistributedFileSystem extends FileSystem {
private Path workingDir;
private URI uri;
DFSClient dfs;
private boolean verifyChecksum = true;
static{
HdfsConfiguration.init();
}
public DistributedFileSystem() {
}
/**
* Return the protocol scheme for the FileSystem.
*
*
* @return hdfs
*/
@Override
public String getScheme() {
return HdfsConstants.HDFS_URI_SCHEME;
}
@Deprecated
public DistributedFileSystem(InetSocketAddress namenode,
Configuration conf) throws IOException {
initialize(NameNode.getUri(namenode), conf);
}
@Override
public URI getUri() { return uri; }
@Override
public void initialize(URI uri, Configuration conf) throws IOException {
super.initialize(uri, conf);
setConf(conf);
String host = uri.getHost();
if (host == null) {
throw new IOException("Incomplete HDFS URI, no host: "+ uri);
}
this.dfs = new DFSClient(uri, conf, statistics);
this.uri = URI.create(uri.getScheme()+"://"+uri.getAuthority());
this.workingDir = getHomeDirectory();
}
@Override
public Path getWorkingDirectory() {
return workingDir;
}
@Override
public long getDefaultBlockSize() {
return dfs.getDefaultBlockSize();
}
@Override
public short getDefaultReplication() {
return dfs.getDefaultReplication();
}
private Path makeAbsolute(Path f) {
if (f.isAbsolute()) {
return f;
} else {
return new Path(workingDir, f);
}
}
@Override
public void setWorkingDirectory(Path dir) {
String result = makeAbsolute(dir).toUri().getPath();
if (!DFSUtil.isValidName(result)) {
throw new IllegalArgumentException("Invalid DFS directory name " +
result);
}
workingDir = makeAbsolute(dir);
}
@Override
public Path getHomeDirectory() {
return makeQualified(new Path("/user/" + dfs.ugi.getShortUserName()));
}
private String getPathName(Path file) {
checkPath(file);
String result = makeAbsolute(file).toUri().getPath();
if (!DFSUtil.isValidName(result)) {
throw new IllegalArgumentException("Pathname " + result + " from " +
file+" is not a valid DFS filename.");
}
return result;
}
@Override
public BlockLocation[] getFileBlockLocations(FileStatus file, long start,
long len) throws IOException {
if (file == null) {
return null;
}
return getFileBlockLocations(file.getPath(), start, len);
}
@Override
public BlockLocation[] getFileBlockLocations(Path p,
long start, long len) throws IOException {
statistics.incrementReadOps(1);
return dfs.getBlockLocations(getPathName(p), start, len);
}
/**
* Used to query storage location information for a list of blocks. This list
* of blocks is normally constructed via a series of calls to
* {@link DistributedFileSystem#getFileBlockLocations(Path, long, long)} to
* get the blocks for ranges of a file.
*
* The returned array of {@link BlockStorageLocation} augments
* {@link BlockLocation} with a {@link VolumeId} per block replica. The
* VolumeId specifies the volume on the datanode on which the replica resides.
* The VolumeId has to be checked via {@link VolumeId#isValid()} before being
* used because volume information can be unavailable if the corresponding
* datanode is down or if the requested block is not found.
*
* This API is unstable, and datanode-side support is enabled by default. It
* can be disabled by setting "dfs.datanode.hdfs-blocks-metadata.enabled" to
* false.
*
* @param blocks
* List of target BlockLocations to query volume location information
* @return volumeBlockLocations Augmented array of
* {@link BlockStorageLocation}s containing additional volume location
* information for each replica of each block.
*/
@InterfaceStability.Unstable
public BlockStorageLocation[] getFileBlockStorageLocations(
List blocks) throws IOException,
UnsupportedOperationException, InvalidBlockTokenException {
return dfs.getBlockStorageLocations(blocks);
}
@Override
public void setVerifyChecksum(boolean verifyChecksum) {
this.verifyChecksum = verifyChecksum;
}
/**
* Start the lease recovery of a file
*
* @param f a file
* @return true if the file is already closed
* @throws IOException if an error occurs
*/
public boolean recoverLease(Path f) throws IOException {
return dfs.recoverLease(getPathName(f));
}
@SuppressWarnings("deprecation")
@Override
public HdfsDataInputStream open(Path f, int bufferSize) throws IOException {
statistics.incrementReadOps(1);
return new DFSClient.DFSDataInputStream(
dfs.open(getPathName(f), bufferSize, verifyChecksum));
}
/** This optional operation is not yet supported. */
@Override
public HdfsDataOutputStream append(Path f, int bufferSize,
Progressable progress) throws IOException {
statistics.incrementWriteOps(1);
return dfs.append(getPathName(f), bufferSize, progress, statistics);
}
@Override
public HdfsDataOutputStream create(Path f, FsPermission permission,
boolean overwrite, int bufferSize, short replication, long blockSize,
Progressable progress) throws IOException {
return this.create(f, permission,
overwrite ? EnumSet.of(CreateFlag.CREATE, CreateFlag.OVERWRITE)
: EnumSet.of(CreateFlag.CREATE), bufferSize, replication,
blockSize, progress, null);
}
@Override
public HdfsDataOutputStream create(Path f, FsPermission permission,
EnumSet cflags, int bufferSize, short replication, long blockSize,
Progressable progress, ChecksumOpt checksumOpt) throws IOException {
statistics.incrementWriteOps(1);
final DFSOutputStream out = dfs.create(getPathName(f), permission, cflags,
replication, blockSize, progress, bufferSize, checksumOpt);
return new HdfsDataOutputStream(out, statistics);
}
@SuppressWarnings("deprecation")
@Override
protected HdfsDataOutputStream primitiveCreate(Path f,
FsPermission absolutePermission, EnumSet flag, int bufferSize,
short replication, long blockSize, Progressable progress,
ChecksumOpt checksumOpt) throws IOException {
statistics.incrementWriteOps(1);
return new HdfsDataOutputStream(dfs.primitiveCreate(getPathName(f),
absolutePermission, flag, true, replication, blockSize,
progress, bufferSize, checksumOpt),statistics);
}
/**
* Same as create(), except fails if parent directory doesn't already exist.
*/
@Override
public HdfsDataOutputStream createNonRecursive(Path f, FsPermission permission,
EnumSet flag, int bufferSize, short replication,
long blockSize, Progressable progress) throws IOException {
statistics.incrementWriteOps(1);
if (flag.contains(CreateFlag.OVERWRITE)) {
flag.add(CreateFlag.CREATE);
}
return new HdfsDataOutputStream(dfs.create(getPathName(f), permission, flag,
false, replication, blockSize, progress,
bufferSize, null), statistics);
}
@Override
public boolean setReplication(Path src,
short replication
) throws IOException {
statistics.incrementWriteOps(1);
return dfs.setReplication(getPathName(src), replication);
}
/**
* Move blocks from srcs to trg
* and delete srcs afterwards
* RESTRICTION: all blocks should be the same size
* @param trg existing file to append to
* @param psrcs list of files (same block size, same replication)
* @throws IOException
*/
public void concat(Path trg, Path [] psrcs) throws IOException {
String [] srcs = new String [psrcs.length];
for(int i=0; i listing =
new ArrayList(totalNumEntries);
// add the first batch of entries to the array list
for (HdfsFileStatus fileStatus : partialListing) {
listing.add(makeQualified(fileStatus, p));
}
statistics.incrementLargeReadOps(1);
// now fetch more entries
do {
thisListing = dfs.listPaths(src, thisListing.getLastName());
if (thisListing == null) { // the directory is deleted
throw new FileNotFoundException("File " + p + " does not exist.");
}
partialListing = thisListing.getPartialListing();
for (HdfsFileStatus fileStatus : partialListing) {
listing.add(makeQualified(fileStatus, p));
}
statistics.incrementLargeReadOps(1);
} while (thisListing.hasMore());
return listing.toArray(new FileStatus[listing.size()]);
}
@Override
protected RemoteIterator listLocatedStatus(final Path p,
final PathFilter filter)
throws IOException {
return new RemoteIterator() {
private DirectoryListing thisListing;
private int i;
private String src;
private LocatedFileStatus curStat = null;
{ // initializer
src = getPathName(p);
// fetch the first batch of entries in the directory
thisListing = dfs.listPaths(src, HdfsFileStatus.EMPTY_NAME, true);
statistics.incrementReadOps(1);
if (thisListing == null) { // the directory does not exist
throw new FileNotFoundException("File " + p + " does not exist.");
}
}
@Override
public boolean hasNext() throws IOException {
while (curStat == null && hasNextNoFilter()) {
LocatedFileStatus next = makeQualifiedLocated(
(HdfsLocatedFileStatus)thisListing.getPartialListing()[i++], p);
if (filter.accept(next.getPath())) {
curStat = next;
}
}
return curStat != null;
}
/** Check if there is a next item before applying the given filter */
private boolean hasNextNoFilter() throws IOException {
if (thisListing == null) {
return false;
}
if (i>=thisListing.getPartialListing().length
&& thisListing.hasMore()) {
// current listing is exhausted & fetch a new listing
thisListing = dfs.listPaths(src, thisListing.getLastName(), true);
statistics.incrementReadOps(1);
if (thisListing == null) {
return false;
}
i = 0;
}
return (i listCorruptFileBlocks(Path path)
throws IOException {
return new CorruptFileBlockIterator(dfs, path);
}
/** @return datanode statistics. */
public DatanodeInfo[] getDataNodeStats() throws IOException {
return getDataNodeStats(DatanodeReportType.ALL);
}
/** @return datanode statistics for the given type. */
public DatanodeInfo[] getDataNodeStats(final DatanodeReportType type
) throws IOException {
return dfs.datanodeReport(type);
}
/**
* Enter, leave or get safe mode.
*
* @see org.apache.hadoop.hdfs.protocol.ClientProtocol#setSafeMode(
* HdfsConstants.SafeModeAction,boolean)
*/
public boolean setSafeMode(HdfsConstants.SafeModeAction action)
throws IOException {
return setSafeMode(action, false);
}
/**
* Enter, leave or get safe mode.
*
* @param action
* One of SafeModeAction.ENTER, SafeModeAction.LEAVE and
* SafeModeAction.GET
* @param isChecked
* If true check only for Active NNs status, else check first NN's
* status
* @see org.apache.hadoop.hdfs.protocol.ClientProtocol#setSafeMode(SafeModeAction, boolean)
*/
public boolean setSafeMode(HdfsConstants.SafeModeAction action,
boolean isChecked) throws IOException {
return dfs.setSafeMode(action, isChecked);
}
/**
* Save namespace image.
*
* @see org.apache.hadoop.hdfs.protocol.ClientProtocol#saveNamespace()
*/
public void saveNamespace() throws AccessControlException, IOException {
dfs.saveNamespace();
}
/**
* Rolls the edit log on the active NameNode.
* Requires super-user privileges.
* @see org.apache.hadoop.hdfs.protocol.ClientProtocol#rollEdits()
* @return the transaction ID of the newly created segment
*/
public long rollEdits() throws AccessControlException, IOException {
return dfs.rollEdits();
}
/**
* enable/disable/check restoreFaileStorage
*
* @see org.apache.hadoop.hdfs.protocol.ClientProtocol#restoreFailedStorage(String arg)
*/
public boolean restoreFailedStorage(String arg)
throws AccessControlException, IOException {
return dfs.restoreFailedStorage(arg);
}
/**
* Refreshes the list of hosts and excluded hosts from the configured
* files.
*/
public void refreshNodes() throws IOException {
dfs.refreshNodes();
}
/**
* Finalize previously upgraded files system state.
* @throws IOException
*/
public void finalizeUpgrade() throws IOException {
dfs.finalizeUpgrade();
}
public UpgradeStatusReport distributedUpgradeProgress(UpgradeAction action
) throws IOException {
return dfs.distributedUpgradeProgress(action);
}
/*
* Requests the namenode to dump data strcutures into specified
* file.
*/
public void metaSave(String pathname) throws IOException {
dfs.metaSave(pathname);
}
@Override
public FsServerDefaults getServerDefaults() throws IOException {
return dfs.getServerDefaults();
}
/**
* We need to find the blocks that didn't match. Likely only one
* is corrupt but we will report both to the namenode. In the future,
* we can consider figuring out exactly which block is corrupt.
*/
// We do not see a need for user to report block checksum errors and do not
// want to rely on user to report block corruptions.
@Deprecated
public boolean reportChecksumFailure(Path f,
FSDataInputStream in, long inPos,
FSDataInputStream sums, long sumsPos) {
if(!(in instanceof HdfsDataInputStream && sums instanceof HdfsDataInputStream))
throw new IllegalArgumentException(
"Input streams must be types of HdfsDataInputStream");
LocatedBlock lblocks[] = new LocatedBlock[2];
// Find block in data stream.
HdfsDataInputStream dfsIn = (HdfsDataInputStream) in;
ExtendedBlock dataBlock = dfsIn.getCurrentBlock();
if (dataBlock == null) {
LOG.error("Error: Current block in data stream is null! ");
return false;
}
DatanodeInfo[] dataNode = {dfsIn.getCurrentDatanode()};
lblocks[0] = new LocatedBlock(dataBlock, dataNode);
LOG.info("Found checksum error in data stream at "
+ dataBlock + " on datanode="
+ dataNode[0]);
// Find block in checksum stream
HdfsDataInputStream dfsSums = (HdfsDataInputStream) sums;
ExtendedBlock sumsBlock = dfsSums.getCurrentBlock();
if (sumsBlock == null) {
LOG.error("Error: Current block in checksum stream is null! ");
return false;
}
DatanodeInfo[] sumsNode = {dfsSums.getCurrentDatanode()};
lblocks[1] = new LocatedBlock(sumsBlock, sumsNode);
LOG.info("Found checksum error in checksum stream at "
+ sumsBlock + " on datanode=" + sumsNode[0]);
// Ask client to delete blocks.
dfs.reportChecksumFailure(f.toString(), lblocks);
return true;
}
/**
* Returns the stat information about the file.
* @throws FileNotFoundException if the file does not exist.
*/
@Override
public FileStatus getFileStatus(Path f) throws IOException {
statistics.incrementReadOps(1);
HdfsFileStatus fi = dfs.getFileInfo(getPathName(f));
if (fi != null) {
return makeQualified(fi, f);
} else {
throw new FileNotFoundException("File does not exist: " + f);
}
}
@Override
public MD5MD5CRC32FileChecksum getFileChecksum(Path f) throws IOException {
statistics.incrementReadOps(1);
return dfs.getFileChecksum(getPathName(f));
}
@Override
public void setPermission(Path p, FsPermission permission
) throws IOException {
statistics.incrementWriteOps(1);
dfs.setPermission(getPathName(p), permission);
}
@Override
public void setOwner(Path p, String username, String groupname
) throws IOException {
if (username == null && groupname == null) {
throw new IOException("username == null && groupname == null");
}
statistics.incrementWriteOps(1);
dfs.setOwner(getPathName(p), username, groupname);
}
@Override
public void setTimes(Path p, long mtime, long atime
) throws IOException {
statistics.incrementWriteOps(1);
dfs.setTimes(getPathName(p), mtime, atime);
}
@Override
protected int getDefaultPort() {
return NameNode.DEFAULT_PORT;
}
@Override
public
Token getDelegationToken(String renewer
) throws IOException {
Token result =
dfs.getDelegationToken(renewer == null ? null : new Text(renewer));
return result;
}
/*
* Delegation Token Operations
* These are DFS only operations.
*/
/**
* Get a valid Delegation Token.
*
* @param renewer Name of the designated renewer for the token
* @return Token
* @throws IOException
* @deprecated use {@link #getDelegationToken(String)}
*/
@Deprecated
public Token getDelegationToken(Text renewer)
throws IOException {
return getDelegationToken(renewer.toString());
}
/**
* Renew an existing delegation token.
*
* @param token delegation token obtained earlier
* @return the new expiration time
* @throws IOException
* @deprecated Use Token.renew instead.
*/
public long renewDelegationToken(Token token)
throws InvalidToken, IOException {
try {
return token.renew(getConf());
} catch (InterruptedException ie) {
throw new RuntimeException("Caught interrupted", ie);
}
}
/**
* Cancel an existing delegation token.
*
* @param token delegation token
* @throws IOException
* @deprecated Use Token.cancel instead.
*/
public void cancelDelegationToken(Token token)
throws IOException {
try {
token.cancel(getConf());
} catch (InterruptedException ie) {
throw new RuntimeException("Caught interrupted", ie);
}
}
/**
* Requests the namenode to tell all datanodes to use a new, non-persistent
* bandwidth value for dfs.balance.bandwidthPerSec.
* The bandwidth parameter is the max number of bytes per second of network
* bandwidth to be used by a datanode during balancing.
*
* @param bandwidth Blanacer bandwidth in bytes per second for all datanodes.
* @throws IOException
*/
public void setBalancerBandwidth(long bandwidth) throws IOException {
dfs.setBalancerBandwidth(bandwidth);
}
/**
* Get a canonical service name for this file system. If the URI is logical,
* the hostname part of the URI will be returned.
* @return a service string that uniquely identifies this file system.
*/
@Override
public String getCanonicalServiceName() {
return dfs.getCanonicalServiceName();
}
@Override
protected URI canonicalizeUri(URI uri) {
if (HAUtil.isLogicalUri(getConf(), uri)) {
// Don't try to DNS-resolve logical URIs, since the 'authority'
// portion isn't a proper hostname
return uri;
} else {
return NetUtils.getCanonicalUri(uri, getDefaultPort());
}
}
/**
* Utility function that returns if the NameNode is in safemode or not. In HA
* mode, this API will return only ActiveNN's safemode status.
*
* @return true if NameNode is in safemode, false otherwise.
* @throws IOException
* when there is an issue communicating with the NameNode
*/
public boolean isInSafeMode() throws IOException {
return setSafeMode(SafeModeAction.SAFEMODE_GET, true);
}
/**
* Get the close status of a file
* @param src The path to the file
*
* @return return true if file is closed
* @throws FileNotFoundException if the file does not exist.
* @throws IOException If an I/O error occurred
* @throws UnsupportedOperationException if the HDFS cluster this client is
* connecting to is running an older version which does not support
* this feature.
*/
public boolean isFileClosed(Path src) throws IOException {
return dfs.isFileClosed(getPathName(src));
}
}
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