Google Git
Sign in
apache / hadoop-mapreduce / 683b1a29066df74468dd4d5d068d2a9b0f5f14e1 / . / src / tools / org / apache / hadoop / tools / DistCp.java
blob: 5cd49f43d4475ecfe618d272cbf559f46c2a0438 [file] [log] [blame]
/**
* 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.tools;
import java.io.BufferedReader;
import java.io.DataInput;
import java.io.DataOutput;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.EnumSet;
import java.util.HashSet;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.Random;
import java.util.Stack;
import java.util.StringTokenizer;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.FileAlreadyExistsException;
import org.apache.hadoop.fs.FileChecksum;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.fs.Trash;
import org.apache.hadoop.fs.permission.FsPermission;
import org.apache.hadoop.hdfs.HftpFileSystem;
import org.apache.hadoop.hdfs.protocol.QuotaExceededException;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.io.SequenceFile;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.io.Writable;
import org.apache.hadoop.io.WritableComparable;
import org.apache.hadoop.ipc.RemoteException;
import org.apache.hadoop.mapred.FileOutputFormat;
import org.apache.hadoop.mapred.FileSplit;
import org.apache.hadoop.mapred.InputFormat;
import org.apache.hadoop.mapred.InputSplit;
import org.apache.hadoop.mapred.InvalidInputException;
import org.apache.hadoop.mapred.JobClient;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.JobTracker;
import org.apache.hadoop.mapred.Mapper;
import org.apache.hadoop.mapred.OutputCollector;
import org.apache.hadoop.mapred.RecordReader;
import org.apache.hadoop.mapred.Reporter;
import org.apache.hadoop.mapred.SequenceFileRecordReader;
import org.apache.hadoop.mapreduce.JobSubmissionFiles;
import org.apache.hadoop.mapreduce.security.TokenCache;
import org.apache.hadoop.security.AccessControlException;
import org.apache.hadoop.util.StringUtils;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;
/**
* A Map-reduce program to recursively copy directories between
* different file-systems.
*/
public class DistCp implements Tool {
public static final Log LOG = LogFactory.getLog(DistCp.class);
private static final String NAME = "distcp";
private static final String usage = NAME
+ " [OPTIONS] <srcurl>* <desturl>" +
"\n\nOPTIONS:" +
"\n-p[rbugp] Preserve status" +
"\n r: replication number" +
"\n b: block size" +
"\n u: user" +
"\n g: group" +
"\n p: permission" +
"\n t: modification and access times" +
"\n -p alone is equivalent to -prbugpt" +
"\n-i Ignore failures" +
"\n-basedir <basedir> Use <basedir> as the base directory when copying files from <srcurl>" +
"\n-log <logdir> Write logs to <logdir>" +
"\n-m <num_maps> Maximum number of simultaneous copies" +
"\n-overwrite Overwrite destination" +
"\n-update Overwrite if src size different from dst size" +
"\n-skipcrccheck Do not use CRC check to determine if src is " +
"\n different from dest. Relevant only if -update" +
"\n is specified" +
"\n-f <urilist_uri> Use list at <urilist_uri> as src list" +
"\n-filelimit <n> Limit the total number of files to be <= n" +
"\n-sizelimit <n> Limit the total size to be <= n bytes" +
"\n-delete Delete the files existing in the dst but not in src" +
"\n-dryrun Display count of files and total size of files" +
"\n in src and then exit. Copy is not done at all." +
"\n desturl should not be speicified with out -update." +
"\n-mapredSslConf <f> Filename of SSL configuration for mapper task" +
"\n\nNOTE 1: if -overwrite or -update are set, each source URI is " +
"\n interpreted as an isomorphic update to an existing directory." +
"\nFor example:" +
"\nhadoop " + NAME + " -p -update \"hdfs://A:8020/user/foo/bar\" " +
"\"hdfs://B:8020/user/foo/baz\"\n" +
"\n would update all descendants of 'baz' also in 'bar'; it would " +
"\n *not* update /user/foo/baz/bar" +
"\n\nNOTE 2: The parameter <n> in -filelimit and -sizelimit can be " +
"\n specified with symbolic representation. For examples," +
"\n 1230k = 1230 * 1024 = 1259520" +
"\n 891g = 891 * 1024^3 = 956703965184" +
"\n";
private static final long BYTES_PER_MAP = 256 * 1024 * 1024;
private static final int MAX_MAPS_PER_NODE = 20;
private static final int SYNC_FILE_MAX = 10;
private static final int DEFAULT_FILE_RETRIES = 3;
static enum Counter { COPY, SKIP, FAIL, BYTESCOPIED, BYTESEXPECTED }
static enum Options {
DELETE("-delete", NAME + ".delete"),
FILE_LIMIT("-filelimit", NAME + ".limit.file"),
SIZE_LIMIT("-sizelimit", NAME + ".limit.size"),
IGNORE_READ_FAILURES("-i", NAME + ".ignore.read.failures"),
PRESERVE_STATUS("-p", NAME + ".preserve.status"),
OVERWRITE("-overwrite", NAME + ".overwrite.always"),
UPDATE("-update", NAME + ".overwrite.ifnewer"),
SKIPCRC("-skipcrccheck", NAME + ".skip.crc.check");
final String cmd, propertyname;
private Options(String cmd, String propertyname) {
this.cmd = cmd;
this.propertyname = propertyname;
}
private long parseLong(String[] args, int offset) {
if (offset == args.length) {
throw new IllegalArgumentException("<n> not specified in " + cmd);
}
long n = StringUtils.TraditionalBinaryPrefix.string2long(args[offset]);
if (n <= 0) {
throw new IllegalArgumentException("n = " + n + " <= 0 in " + cmd);
}
return n;
}
}
static enum FileAttribute {
BLOCK_SIZE, REPLICATION, USER, GROUP, PERMISSION, TIMES;
final char symbol;
private FileAttribute() {symbol = toString().toLowerCase().charAt(0);}
static EnumSet<FileAttribute> parse(String s) {
if (s == null || s.length() == 0) {
return EnumSet.allOf(FileAttribute.class);
}
EnumSet<FileAttribute> set = EnumSet.noneOf(FileAttribute.class);
FileAttribute[] attributes = values();
for(char c : s.toCharArray()) {
int i = 0;
for(; i < attributes.length && c != attributes[i].symbol; i++);
if (i < attributes.length) {
if (!set.contains(attributes[i])) {
set.add(attributes[i]);
} else {
throw new IllegalArgumentException("There are more than one '"
+ attributes[i].symbol + "' in " + s);
}
} else {
throw new IllegalArgumentException("'" + c + "' in " + s
+ " is undefined.");
}
}
return set;
}
}
static final String TMP_DIR_LABEL = NAME + ".tmp.dir";
static final String DST_DIR_LABEL = NAME + ".dest.path";
static final String JOB_DIR_LABEL = NAME + ".job.dir";
static final String MAX_MAPS_LABEL = NAME + ".max.map.tasks";
static final String SRC_LIST_LABEL = NAME + ".src.list";
static final String SRC_COUNT_LABEL = NAME + ".src.count";
static final String TOTAL_SIZE_LABEL = NAME + ".total.size";
static final String DST_DIR_LIST_LABEL = NAME + ".dst.dir.list";
static final String BYTES_PER_MAP_LABEL = NAME + ".bytes.per.map";
static final String PRESERVE_STATUS_LABEL
= Options.PRESERVE_STATUS.propertyname + ".value";
static final String FILE_RETRIES_LABEL = NAME + ".file.retries";
private JobConf conf;
public void setConf(Configuration conf) {
if (conf instanceof JobConf) {
this.conf = (JobConf) conf;
} else {
this.conf = new JobConf(conf);
}
}
public Configuration getConf() {
return conf;
}
public DistCp(Configuration conf) {
setConf(conf);
}
/**
* An input/output pair of filenames.
*/
static class FilePair implements Writable {
FileStatus input = new FileStatus();
String output;
FilePair() { }
FilePair(FileStatus input, String output) {
this.input = input;
this.output = output;
}
public void readFields(DataInput in) throws IOException {
input.readFields(in);
output = Text.readString(in);
}
public void write(DataOutput out) throws IOException {
input.write(out);
Text.writeString(out, output);
}
public String toString() {
return input + " : " + output;
}
}
/**
* InputFormat of a distcp job responsible for generating splits of the src
* file list.
*/
static class CopyInputFormat implements InputFormat<Text, Text> {
/**
* Produce splits such that each is no greater than the quotient of the
* total size and the number of splits requested.
* @param job The handle to the JobConf object
* @param numSplits Number of splits requested
*/
public InputSplit[] getSplits(JobConf job, int numSplits)
throws IOException {
int cnfiles = job.getInt(SRC_COUNT_LABEL, -1);
long cbsize = job.getLong(TOTAL_SIZE_LABEL, -1);
String srcfilelist = job.get(SRC_LIST_LABEL, "");
if (cnfiles < 0 || cbsize < 0 || "".equals(srcfilelist)) {
throw new RuntimeException("Invalid metadata: #files(" + cnfiles +
") total_size(" + cbsize + ") listuri(" +
srcfilelist + ")");
}
Path src = new Path(srcfilelist);
FileSystem fs = src.getFileSystem(job);
FileStatus srcst = fs.getFileStatus(src);
ArrayList<FileSplit> splits = new ArrayList<FileSplit>(numSplits);
LongWritable key = new LongWritable();
FilePair value = new FilePair();
final long targetsize = cbsize / numSplits;
long pos = 0L;
long last = 0L;
long acc = 0L;
long cbrem = srcst.getLen();
SequenceFile.Reader sl = null;
try {
sl = new SequenceFile.Reader(fs, src, job);
for (; sl.next(key, value); last = sl.getPosition()) {
// if adding this split would put this split past the target size,
// cut the last split and put this next file in the next split.
if (acc + key.get() > targetsize && acc != 0) {
long splitsize = last - pos;
splits.add(new FileSplit(src, pos, splitsize, (String[])null));
cbrem -= splitsize;
pos = last;
acc = 0L;
}
acc += key.get();
}
}
finally {
checkAndClose(sl);
}
if (cbrem != 0) {
splits.add(new FileSplit(src, pos, cbrem, (String[])null));
}
return splits.toArray(new FileSplit[splits.size()]);
}
/**
* Returns a reader for this split of the src file list.
*/
public RecordReader<Text, Text> getRecordReader(InputSplit split,
JobConf job, Reporter reporter) throws IOException {
return new SequenceFileRecordReader<Text, Text>(job, (FileSplit)split);
}
}
/**
* FSCopyFilesMapper: The mapper for copying files between FileSystems.
*/
static class CopyFilesMapper
implements Mapper<LongWritable, FilePair, WritableComparable<?>, Text> {
// config
private int sizeBuf = 128 * 1024;
private FileSystem destFileSys = null;
private boolean ignoreReadFailures;
private boolean preserve_status;
private EnumSet<FileAttribute> preseved;
private boolean overwrite;
private boolean update;
private Path destPath = null;
private byte[] buffer = null;
private JobConf job;
private boolean skipCRCCheck = false;
// stats
private int failcount = 0;
private int skipcount = 0;
private int copycount = 0;
private String getCountString() {
return "Copied: " + copycount + " Skipped: " + skipcount
+ " Failed: " + failcount;
}
private void updateStatus(Reporter reporter) {
reporter.setStatus(getCountString());
}
/**
* Return true if dst should be replaced by src and the update flag is set.
* Right now, this merely checks that the src and dst len are not equal.
* This should be improved on once modification times, CRCs, etc. can
* be meaningful in this context.
* @throws IOException
*/
private boolean needsUpdate(FileStatus srcstatus,
FileSystem dstfs, Path dstpath) throws IOException {
return update && !sameFile(srcstatus.getPath().getFileSystem(job),
srcstatus, dstfs, dstpath, skipCRCCheck);
}
private FSDataOutputStream create(Path f, Reporter reporter,
FileStatus srcstat) throws IOException {
if (destFileSys.exists(f)) {
destFileSys.delete(f, false);
}
if (!preserve_status) {
return destFileSys.create(f, true, sizeBuf, reporter);
}
FsPermission permission = preseved.contains(FileAttribute.PERMISSION)?
srcstat.getPermission(): null;
short replication = preseved.contains(FileAttribute.REPLICATION)?
srcstat.getReplication(): destFileSys.getDefaultReplication();
long blockSize = preseved.contains(FileAttribute.BLOCK_SIZE)?
srcstat.getBlockSize(): destFileSys.getDefaultBlockSize();
return destFileSys.create(f, permission, true, sizeBuf, replication,
blockSize, reporter);
}
/**
* Validates copy by checking the sizes of files first and then
* checksums, if the filesystems support checksums.
* @param srcstat src path and metadata
* @param absdst dst path
* @return true if src & destination files are same
*/
private boolean validateCopy(FileStatus srcstat, Path absdst)
throws IOException {
if (destFileSys.exists(absdst)) {
if (sameFile(srcstat.getPath().getFileSystem(job), srcstat,
destFileSys, absdst, skipCRCCheck)) {
return true;
}
}
return false;
}
/**
* Increment number of files copied and bytes copied and then report status
*/
void updateCopyStatus(FileStatus srcstat, Reporter reporter) {
copycount++;
reporter.incrCounter(Counter.BYTESCOPIED, srcstat.getLen());
reporter.incrCounter(Counter.COPY, 1);
updateStatus(reporter);
}
/**
* Skip copying this file if already exists at the destination.
* Updates counters and copy status if skipping this file.
* @return true if copy of this file can be skipped
*/
private boolean skipCopyFile(FileStatus srcstat, Path absdst,
OutputCollector<WritableComparable<?>, Text> outc,
Reporter reporter) throws IOException {
if (destFileSys.exists(absdst) && !overwrite
&& !needsUpdate(srcstat, destFileSys, absdst)) {
outc.collect(null, new Text("SKIP: " + srcstat.getPath()));
++skipcount;
reporter.incrCounter(Counter.SKIP, 1);
updateStatus(reporter);
return true;
}
return false;
}
/**
* Copies single file to the path specified by tmpfile.
* @param srcstat src path and metadata
* @param tmpfile temporary file to which copy is to be done
* @param absdst actual destination path to which copy is to be done
* @param reporter
* @return Number of bytes copied
*/
private long doCopyFile(FileStatus srcstat, Path tmpfile, Path absdst,
Reporter reporter) throws IOException {
FSDataInputStream in = null;
FSDataOutputStream out = null;
long bytesCopied = 0L;
try {
Path srcPath = srcstat.getPath();
// open src file
in = srcPath.getFileSystem(job).open(srcPath);
reporter.incrCounter(Counter.BYTESEXPECTED, srcstat.getLen());
// open tmp file
out = create(tmpfile, reporter, srcstat);
LOG.info("Copying file " + srcPath + " of size " +
srcstat.getLen() + " bytes...");
// copy file
for(int bytesRead; (bytesRead = in.read(buffer)) >= 0; ) {
out.write(buffer, 0, bytesRead);
bytesCopied += bytesRead;
reporter.setStatus(
String.format("%.2f ", bytesCopied*100.0/srcstat.getLen())
+ absdst + " [ " +
StringUtils.humanReadableInt(bytesCopied) + " / " +
StringUtils.humanReadableInt(srcstat.getLen()) + " ]");
}
} finally {
checkAndClose(in);
checkAndClose(out);
}
return bytesCopied;
}
/**
* Copy a file to a destination.
* @param srcstat src path and metadata
* @param dstpath dst path
* @param reporter
* @throws IOException if copy fails(even if the validation of copy fails)
*/
private void copy(FileStatus srcstat, Path relativedst,
OutputCollector<WritableComparable<?>, Text> outc, Reporter reporter)
throws IOException {
Path absdst = new Path(destPath, relativedst);
int totfiles = job.getInt(SRC_COUNT_LABEL, -1);
assert totfiles >= 0 : "Invalid file count " + totfiles;
if (totfiles == 1) {
// Copying a single file; use dst path provided by user as
// destination file rather than destination directory
Path dstparent = absdst.getParent();
if (!(destFileSys.exists(dstparent) &&
destFileSys.getFileStatus(dstparent).isDirectory())) {
absdst = dstparent;
}
}
// if a directory, ensure created even if empty
if (srcstat.isDirectory()) {
if (destFileSys.exists(absdst)) {
if (destFileSys.getFileStatus(absdst).isFile()) {
throw new IOException("Failed to mkdirs: " + absdst+" is a file.");
}
}
else if (!destFileSys.mkdirs(absdst)) {
throw new IOException("Failed to mkdirs " + absdst);
}
// TODO: when modification times can be set, directories should be
// emitted to reducers so they might be preserved. Also, mkdirs does
// not currently return an error when the directory already exists;
// if this changes, all directory work might as well be done in reduce
return;
}
// Can we skip copying this file ?
if (skipCopyFile(srcstat, absdst, outc, reporter)) {
return;
}
Path tmpfile = new Path(job.get(TMP_DIR_LABEL), relativedst);
// do the actual copy to tmpfile
long bytesCopied = doCopyFile(srcstat, tmpfile, absdst, reporter);
if (bytesCopied != srcstat.getLen()) {
throw new IOException("File size not matched: copied "
+ bytesString(bytesCopied) + " to tmpfile (=" + tmpfile
+ ") but expected " + bytesString(srcstat.getLen())
+ " from " + srcstat.getPath());
}
else {
if (destFileSys.exists(absdst) &&
destFileSys.getFileStatus(absdst).isDirectory()) {
throw new IOException(absdst + " is a directory");
}
if (!destFileSys.mkdirs(absdst.getParent())) {
throw new IOException("Failed to create parent dir: " + absdst.getParent());
}
rename(tmpfile, absdst);
if (!validateCopy(srcstat, absdst)) {
destFileSys.delete(absdst, false);
throw new IOException("Validation of copy of file "
+ srcstat.getPath() + " failed.");
}
updateDestStatus(srcstat, destFileSys.getFileStatus(absdst));
}
// report at least once for each file
updateCopyStatus(srcstat, reporter);
}
/** rename tmp to dst, delete dst if already exists */
private void rename(Path tmp, Path dst) throws IOException {
try {
if (destFileSys.exists(dst)) {
destFileSys.delete(dst, true);
}
if (!destFileSys.rename(tmp, dst)) {
throw new IOException();
}
}
catch(IOException cause) {
throw (IOException)new IOException("Fail to rename tmp file (=" + tmp
+ ") to destination file (=" + dst + ")").initCause(cause);
}
}
private void updateDestStatus(FileStatus src, FileStatus dst
) throws IOException {
if (preserve_status) {
DistCp.updateDestStatus(src, dst, preseved, destFileSys);
}
}
static String bytesString(long b) {
return b + " bytes (" + StringUtils.humanReadableInt(b) + ")";
}
/**
* Copies a file and validates the copy by checking the checksums.
* If validation fails, retries (max number of tries is distcp.file.retries)
* to copy the file.
*/
void copyWithRetries(FileStatus srcstat, Path relativedst,
OutputCollector<WritableComparable<?>, Text> out,
Reporter reporter) throws IOException {
// max tries to copy when validation of copy fails
final int maxRetries = job.getInt(FILE_RETRIES_LABEL, DEFAULT_FILE_RETRIES);
// save update flag for later copies within the same map task
final boolean saveUpdate = update;
int retryCnt = 1;
for (; retryCnt <= maxRetries; retryCnt++) {
try {
//copy the file and validate copy
copy(srcstat, relativedst, out, reporter);
break;// copy successful
} catch (IOException e) {
LOG.warn("Copy of " + srcstat.getPath() + " failed.", e);
if (retryCnt < maxRetries) {// copy failed and need to retry
LOG.info("Retrying copy of file " + srcstat.getPath());
update = true; // set update flag for retries
}
else {// no more retries... Give up
update = saveUpdate;
throw new IOException("Copy of file failed even with " + retryCnt
+ " tries.", e);
}
}
}
}
/** Mapper configuration.
* Extracts source and destination file system, as well as
* top-level paths on source and destination directories.
* Gets the named file systems, to be used later in map.
*/
public void configure(JobConf job)
{
destPath = new Path(job.get(DST_DIR_LABEL, "/"));
try {
destFileSys = destPath.getFileSystem(job);
} catch (IOException ex) {
throw new RuntimeException("Unable to get the named file system.", ex);
}
sizeBuf = job.getInt("copy.buf.size", 128 * 1024);
buffer = new byte[sizeBuf];
ignoreReadFailures = job.getBoolean(Options.IGNORE_READ_FAILURES.propertyname, false);
preserve_status = job.getBoolean(Options.PRESERVE_STATUS.propertyname, false);
if (preserve_status) {
preseved = FileAttribute.parse(job.get(PRESERVE_STATUS_LABEL));
}
update = job.getBoolean(Options.UPDATE.propertyname, false);
overwrite = !update && job.getBoolean(Options.OVERWRITE.propertyname, false);
skipCRCCheck = job.getBoolean(Options.SKIPCRC.propertyname, false);
this.job = job;
}
/** Map method. Copies one file from source file system to destination.
* @param key src len
* @param value FilePair (FileStatus src, Path dst)
* @param out Log of failed copies
* @param reporter
*/
public void map(LongWritable key,
FilePair value,
OutputCollector<WritableComparable<?>, Text> out,
Reporter reporter) throws IOException {
final FileStatus srcstat = value.input;
final Path relativedst = new Path(value.output);
try {
copyWithRetries(srcstat, relativedst, out, reporter);
} catch (IOException e) {
++failcount;
reporter.incrCounter(Counter.FAIL, 1);
updateStatus(reporter);
final String sfailure = "FAIL " + relativedst + " : " +
StringUtils.stringifyException(e);
out.collect(null, new Text(sfailure));
LOG.info(sfailure);
if (e instanceof FileNotFoundException) {
final String s = "Possible Cause for failure: Either the filesystem "
+ srcstat.getPath().getFileSystem(job)
+ " is not accessible or the file is deleted";
LOG.error(s);
out.collect(null, new Text(s));
}
try {
for (int i = 0; i < 3; ++i) {
try {
final Path tmp = new Path(job.get(TMP_DIR_LABEL), relativedst);
if (destFileSys.delete(tmp, true))
break;
} catch (Throwable ex) {
// ignore, we are just cleaning up
LOG.debug("Ignoring cleanup exception", ex);
}
// update status, so we don't get timed out
updateStatus(reporter);
Thread.sleep(3 * 1000);
}
} catch (InterruptedException inte) {
throw (IOException)new IOException().initCause(inte);
}
} finally {
updateStatus(reporter);
}
}
public void close() throws IOException {
if (0 == failcount || ignoreReadFailures) {
return;
}
throw new IOException(getCountString());
}
}
private static List<Path> fetchFileList(Configuration conf, Path srcList)
throws IOException {
List<Path> result = new ArrayList<Path>();
FileSystem fs = srcList.getFileSystem(conf);
BufferedReader input = null;
try {
input = new BufferedReader(new InputStreamReader(fs.open(srcList)));
String line = input.readLine();
while (line != null) {
result.add(new Path(line));
line = input.readLine();
}
} finally {
checkAndClose(input);
}
return result;
}
@Deprecated
public static void copy(Configuration conf, String srcPath,
String destPath, Path logPath,
boolean srcAsList, boolean ignoreReadFailures)
throws IOException {
final Path src = new Path(srcPath);
List<Path> tmp = new ArrayList<Path>();
if (srcAsList) {
tmp.addAll(fetchFileList(conf, src));
} else {
tmp.add(src);
}
EnumSet<Options> flags = ignoreReadFailures
? EnumSet.of(Options.IGNORE_READ_FAILURES)
: EnumSet.noneOf(Options.class);
final Path dst = new Path(destPath);
copy(conf, new Arguments(tmp, null, dst, logPath, flags, null,
Long.MAX_VALUE, Long.MAX_VALUE, null, false));
}
/** Sanity check for srcPath */
private static void checkSrcPath(JobConf jobConf, List<Path> srcPaths)
throws IOException {
List<IOException> rslt = new ArrayList<IOException>();
List<Path> unglobbed = new LinkedList<Path>();
Path[] ps = new Path[srcPaths.size()];
ps = srcPaths.toArray(ps);
TokenCache.obtainTokensForNamenodes(jobConf.getCredentials(), ps, jobConf);
for (Path p : srcPaths) {
FileSystem fs = p.getFileSystem(jobConf);
FileStatus[] inputs = fs.globStatus(p);
if(inputs != null && inputs.length > 0) {
for (FileStatus onePath: inputs) {
unglobbed.add(onePath.getPath());
}
} else {
rslt.add(new IOException("Input source " + p + " does not exist."));
}
}
if (!rslt.isEmpty()) {
throw new InvalidInputException(rslt);
}
srcPaths.clear();
srcPaths.addAll(unglobbed);
}
/**
* Driver to copy srcPath to destPath depending on required protocol.
* @param args arguments
*/
static void copy(final Configuration conf, final Arguments args
) throws IOException {
LOG.info("srcPaths=" + args.srcs);
if (!args.dryrun || args.flags.contains(Options.UPDATE)) {
LOG.info("destPath=" + args.dst);
}
JobConf job = createJobConf(conf);
checkSrcPath(job, args.srcs);
if (args.preservedAttributes != null) {
job.set(PRESERVE_STATUS_LABEL, args.preservedAttributes);
}
if (args.mapredSslConf != null) {
job.set("dfs.https.client.keystore.resource", args.mapredSslConf);
}
//Initialize the mapper
try {
if (setup(conf, job, args)) {
JobClient.runJob(job);
}
if(!args.dryrun) {
finalize(conf, job, args.dst, args.preservedAttributes);
}
} finally {
if (!args.dryrun) {
//delete tmp
fullyDelete(job.get(TMP_DIR_LABEL), job);
}
//delete jobDirectory
fullyDelete(job.get(JOB_DIR_LABEL), job);
}
}
private static void updateDestStatus(FileStatus src, FileStatus dst,
EnumSet<FileAttribute> preseved, FileSystem destFileSys
) throws IOException {
String owner = null;
String group = null;
if (preseved.contains(FileAttribute.USER)
&& !src.getOwner().equals(dst.getOwner())) {
owner = src.getOwner();
}
if (preseved.contains(FileAttribute.GROUP)
&& !src.getGroup().equals(dst.getGroup())) {
group = src.getGroup();
}
if (owner != null || group != null) {
destFileSys.setOwner(dst.getPath(), owner, group);
}
if (preseved.contains(FileAttribute.PERMISSION)
&& !src.getPermission().equals(dst.getPermission())) {
destFileSys.setPermission(dst.getPath(), src.getPermission());
}
if (preseved.contains(FileAttribute.TIMES)) {
destFileSys.setTimes(dst.getPath(), src.getModificationTime(), src.getAccessTime());
}
}
static private void finalize(Configuration conf, JobConf jobconf,
final Path destPath, String presevedAttributes) throws IOException {
if (presevedAttributes == null) {
return;
}
EnumSet<FileAttribute> preseved = FileAttribute.parse(presevedAttributes);
if (!preseved.contains(FileAttribute.USER)
&& !preseved.contains(FileAttribute.GROUP)
&& !preseved.contains(FileAttribute.PERMISSION)) {
return;
}
FileSystem dstfs = destPath.getFileSystem(conf);
Path dstdirlist = new Path(jobconf.get(DST_DIR_LIST_LABEL));
SequenceFile.Reader in = null;
try {
in = new SequenceFile.Reader(dstdirlist.getFileSystem(jobconf),
dstdirlist, jobconf);
Text dsttext = new Text();
FilePair pair = new FilePair();
for(; in.next(dsttext, pair); ) {
Path absdst = new Path(destPath, pair.output);
updateDestStatus(pair.input, dstfs.getFileStatus(absdst),
preseved, dstfs);
}
} finally {
checkAndClose(in);
}
}
static class Arguments {
final List<Path> srcs;
final Path basedir;
final Path dst;
final Path log;
final EnumSet<Options> flags;
final String preservedAttributes;
final long filelimit;
final long sizelimit;
final String mapredSslConf;
final boolean dryrun;
/**
* Arguments for distcp
* @param srcs List of source paths
* @param basedir Base directory for copy
* @param dst Destination path
* @param log Log output directory
* @param flags Command-line flags
* @param preservedAttributes Preserved attributes
* @param filelimit File limit
* @param sizelimit Size limit
*/
Arguments(List<Path> srcs, Path basedir, Path dst, Path log,
EnumSet<Options> flags, String preservedAttributes,
long filelimit, long sizelimit, String mapredSslConf,
boolean dryrun) {
this.srcs = srcs;
this.basedir = basedir;
this.dst = dst;
this.log = log;
this.flags = flags;
this.preservedAttributes = preservedAttributes;
this.filelimit = filelimit;
this.sizelimit = sizelimit;
this.mapredSslConf = mapredSslConf;
this.dryrun = dryrun;
if (LOG.isTraceEnabled()) {
LOG.trace("this = " + this);
}
}
static Arguments valueOf(String[] args, Configuration conf
) throws IOException {
List<Path> srcs = new ArrayList<Path>();
Path dst = null;
Path log = null;
Path basedir = null;
EnumSet<Options> flags = EnumSet.noneOf(Options.class);
String presevedAttributes = null;
String mapredSslConf = null;
long filelimit = Long.MAX_VALUE;
long sizelimit = Long.MAX_VALUE;
boolean dryrun = false;
for (int idx = 0; idx < args.length; idx++) {
Options[] opt = Options.values();
int i = 0;
for(; i < opt.length && !args[idx].startsWith(opt[i].cmd); i++);
if (i < opt.length) {
flags.add(opt[i]);
if (opt[i] == Options.PRESERVE_STATUS) {
presevedAttributes = args[idx].substring(2);
FileAttribute.parse(presevedAttributes); //validation
}
else if (opt[i] == Options.FILE_LIMIT) {
filelimit = Options.FILE_LIMIT.parseLong(args, ++idx);
}
else if (opt[i] == Options.SIZE_LIMIT) {
sizelimit = Options.SIZE_LIMIT.parseLong(args, ++idx);
}
} else if ("-f".equals(args[idx])) {
if (++idx == args.length) {
throw new IllegalArgumentException("urilist_uri not specified in -f");
}
srcs.addAll(fetchFileList(conf, new Path(args[idx])));
} else if ("-log".equals(args[idx])) {
if (++idx == args.length) {
throw new IllegalArgumentException("logdir not specified in -log");
}
log = new Path(args[idx]);
} else if ("-basedir".equals(args[idx])) {
if (++idx == args.length) {
throw new IllegalArgumentException("basedir not specified in -basedir");
}
basedir = new Path(args[idx]);
} else if ("-mapredSslConf".equals(args[idx])) {
if (++idx == args.length) {
throw new IllegalArgumentException("ssl conf file not specified in -mapredSslConf");
}
mapredSslConf = args[idx];
} else if ("-dryrun".equals(args[idx])) {
dryrun = true;
dst = new Path("/tmp/distcp_dummy_dest");//dummy destination
} else if ("-m".equals(args[idx])) {
if (++idx == args.length) {
throw new IllegalArgumentException("num_maps not specified in -m");
}
try {
conf.setInt(MAX_MAPS_LABEL, Integer.valueOf(args[idx]));
} catch (NumberFormatException e) {
throw new IllegalArgumentException("Invalid argument to -m: " +
args[idx]);
}
} else if ('-' == args[idx].codePointAt(0)) {
throw new IllegalArgumentException("Invalid switch " + args[idx]);
} else if (idx == args.length -1 &&
(!dryrun || flags.contains(Options.UPDATE))) {
dst = new Path(args[idx]);
} else {
srcs.add(new Path(args[idx]));
}
}
// mandatory command-line parameters
if (srcs.isEmpty() || dst == null) {
throw new IllegalArgumentException("Missing "
+ (dst == null ? "dst path" : "src"));
}
// incompatible command-line flags
final boolean isOverwrite = flags.contains(Options.OVERWRITE);
final boolean isUpdate = flags.contains(Options.UPDATE);
final boolean isDelete = flags.contains(Options.DELETE);
final boolean skipCRC = flags.contains(Options.SKIPCRC);
if (isOverwrite && isUpdate) {
throw new IllegalArgumentException("Conflicting overwrite policies");
}
if (!isUpdate && skipCRC) {
throw new IllegalArgumentException(
Options.SKIPCRC.cmd + " is relevant only with the " +
Options.UPDATE.cmd + " option");
}
if (isDelete && !isOverwrite && !isUpdate) {
throw new IllegalArgumentException(Options.DELETE.cmd
+ " must be specified with " + Options.OVERWRITE + " or "
+ Options.UPDATE + ".");
}
return new Arguments(srcs, basedir, dst, log, flags, presevedAttributes,
filelimit, sizelimit, mapredSslConf, dryrun);
}
/** {@inheritDoc} */
public String toString() {
return getClass().getName() + "{"
+ "\n srcs = " + srcs
+ "\n dst = " + dst
+ "\n log = " + log
+ "\n flags = " + flags
+ "\n preservedAttributes = " + preservedAttributes
+ "\n filelimit = " + filelimit
+ "\n sizelimit = " + sizelimit
+ "\n mapredSslConf = " + mapredSslConf
+ "\n}";
}
}
/**
* This is the main driver for recursively copying directories
* across file systems. It takes at least two cmdline parameters. A source
* URL and a destination URL. It then essentially does an "ls -lR" on the
* source URL, and writes the output in a round-robin manner to all the map
* input files. The mapper actually copies the files allotted to it. The
* reduce is empty.
*/
public int run(String[] args) {
try {
copy(conf, Arguments.valueOf(args, conf));
return 0;
} catch (IllegalArgumentException e) {
System.err.println(StringUtils.stringifyException(e) + "\n" + usage);
ToolRunner.printGenericCommandUsage(System.err);
return -1;
} catch (DuplicationException e) {
System.err.println(StringUtils.stringifyException(e));
return DuplicationException.ERROR_CODE;
} catch (RemoteException e) {
final IOException unwrapped = e.unwrapRemoteException(
FileNotFoundException.class,
AccessControlException.class,
QuotaExceededException.class);
System.err.println(StringUtils.stringifyException(unwrapped));
return -3;
} catch (Exception e) {
System.err.println("With failures, global counters are inaccurate; " +
"consider running with -i");
System.err.println("Copy failed: " + StringUtils.stringifyException(e));
return -999;
}
}
public static void main(String[] args) throws Exception {
JobConf job = new JobConf(DistCp.class);
DistCp distcp = new DistCp(job);
int res = ToolRunner.run(distcp, args);
System.exit(res);
}
/**
* Make a path relative with respect to a root path.
* absPath is always assumed to descend from root.
* Otherwise returned path is null.
*/
static String makeRelative(Path root, Path absPath) {
if (!absPath.isAbsolute()) {
throw new IllegalArgumentException("!absPath.isAbsolute(), absPath="
+ absPath);
}
String p = absPath.toUri().getPath();
StringTokenizer pathTokens = new StringTokenizer(p, "/");
for(StringTokenizer rootTokens = new StringTokenizer(
root.toUri().getPath(), "/"); rootTokens.hasMoreTokens(); ) {
if (!rootTokens.nextToken().equals(pathTokens.nextToken())) {
return null;
}
}
StringBuilder sb = new StringBuilder();
for(; pathTokens.hasMoreTokens(); ) {
sb.append(pathTokens.nextToken());
if (pathTokens.hasMoreTokens()) { sb.append(Path.SEPARATOR); }
}
return sb.length() == 0? ".": sb.toString();
}
/**
* Calculate how many maps to run.
* Number of maps is bounded by a minimum of the cumulative size of the
* copy / (distcp.bytes.per.map, default BYTES_PER_MAP or -m on the
* command line) and at most (distcp.max.map.tasks, default
* MAX_MAPS_PER_NODE * nodes in the cluster).
* @param totalBytes Count of total bytes for job
* @param job The job to configure
* @return Count of maps to run.
*/
private static int setMapCount(long totalBytes, JobConf job)
throws IOException {
int numMaps =
(int)(totalBytes / job.getLong(BYTES_PER_MAP_LABEL, BYTES_PER_MAP));
numMaps = Math.min(numMaps,
job.getInt(MAX_MAPS_LABEL, MAX_MAPS_PER_NODE *
new JobClient(job).getClusterStatus().getTaskTrackers()));
numMaps = Math.max(numMaps, 1);
job.setNumMapTasks(numMaps);
return numMaps;
}
/** Fully delete dir */
static void fullyDelete(String dir, Configuration conf) throws IOException {
if (dir != null) {
Path tmp = new Path(dir);
boolean success = tmp.getFileSystem(conf).delete(tmp, true);
if (!success) {
LOG.warn("Could not fully delete " + tmp);
}
}
}
//Job configuration
private static JobConf createJobConf(Configuration conf) {
JobConf jobconf = new JobConf(conf, DistCp.class);
jobconf.setJobName(conf.get("mapred.job.name", NAME));
// turn off speculative execution, because DFS doesn't handle
// multiple writers to the same file.
jobconf.setMapSpeculativeExecution(false);
jobconf.setInputFormat(CopyInputFormat.class);
jobconf.setOutputKeyClass(Text.class);
jobconf.setOutputValueClass(Text.class);
jobconf.setMapperClass(CopyFilesMapper.class);
jobconf.setNumReduceTasks(0);
return jobconf;
}
private static final Random RANDOM = new Random();
public static String getRandomId() {
return Integer.toString(RANDOM.nextInt(Integer.MAX_VALUE), 36);
}
/**
* Increase the replication factor of _distcp_src_files to
* sqrt(min(maxMapsOnCluster, numMaps)). This is to reduce the chance of
* failing of distcp because of "not having a replication of _distcp_src_files
* available for reading for some maps".
*/
private static void setReplication(Configuration conf, JobConf jobConf,
Path srcfilelist, int numMaps) throws IOException {
int numMaxMaps = new JobClient(jobConf).getClusterStatus().getMaxMapTasks();
short replication = (short) Math.ceil(
Math.sqrt(Math.min(numMaxMaps, numMaps)));
FileSystem fs = srcfilelist.getFileSystem(conf);
FileStatus srcStatus = fs.getFileStatus(srcfilelist);
if (srcStatus.getReplication() < replication) {
if (!fs.setReplication(srcfilelist, replication)) {
throw new IOException("Unable to increase the replication of file " +
srcfilelist);
}
}
}
/**
* Does the dir already exist at destination ?
* @return true if the dir already exists at destination
*/
private static boolean dirExists(Configuration conf, Path dst)
throws IOException {
FileSystem destFileSys = dst.getFileSystem(conf);
FileStatus status = null;
try {
status = destFileSys.getFileStatus(dst);
}catch (FileNotFoundException e) {
return false;
}
if (status.isFile()) {
throw new FileAlreadyExistsException("Not a dir: " + dst+" is a file.");
}
return true;
}
/**
* Initialize DFSCopyFileMapper specific job-configuration.
* @param conf : The dfs/mapred configuration.
* @param jobConf : The handle to the jobConf object to be initialized.
* @param args Arguments
* @return true if it is necessary to launch a job.
*/
static boolean setup(Configuration conf, JobConf jobConf,
final Arguments args)
throws IOException {
jobConf.set(DST_DIR_LABEL, args.dst.toUri().toString());
//set boolean values
final boolean update = args.flags.contains(Options.UPDATE);
final boolean skipCRCCheck = args.flags.contains(Options.SKIPCRC);
final boolean overwrite = !update && args.flags.contains(Options.OVERWRITE)
&& !args.dryrun;
jobConf.setBoolean(Options.UPDATE.propertyname, update);
jobConf.setBoolean(Options.SKIPCRC.propertyname, skipCRCCheck);
jobConf.setBoolean(Options.OVERWRITE.propertyname, overwrite);
jobConf.setBoolean(Options.IGNORE_READ_FAILURES.propertyname,
args.flags.contains(Options.IGNORE_READ_FAILURES));
jobConf.setBoolean(Options.PRESERVE_STATUS.propertyname,
args.flags.contains(Options.PRESERVE_STATUS));
final String randomId = getRandomId();
JobClient jClient = new JobClient(jobConf);
Path stagingArea;
try {
stagingArea =
JobSubmissionFiles.getStagingDir(jClient.getClusterHandle(), conf);
} catch (InterruptedException ie) {
throw new IOException(ie);
}
Path jobDirectory = new Path(stagingArea + NAME + "_" + randomId);
FsPermission mapredSysPerms =
new FsPermission(JobSubmissionFiles.JOB_DIR_PERMISSION);
FileSystem.mkdirs(jClient.getFs(), jobDirectory, mapredSysPerms);
jobConf.set(JOB_DIR_LABEL, jobDirectory.toString());
long maxBytesPerMap = conf.getLong(BYTES_PER_MAP_LABEL, BYTES_PER_MAP);
FileSystem dstfs = args.dst.getFileSystem(conf);
// get tokens for all the required FileSystems..
TokenCache.obtainTokensForNamenodes(jobConf.getCredentials(),
new Path[] {args.dst}, conf);
boolean dstExists = dstfs.exists(args.dst);
boolean dstIsDir = false;
if (dstExists) {
dstIsDir = dstfs.getFileStatus(args.dst).isDirectory();
}
// default logPath
Path logPath = args.log;
if (logPath == null) {
String filename = "_distcp_logs_" + randomId;
if (!dstExists || !dstIsDir) {
Path parent = args.dst.getParent();
if (null == parent) {
// If dst is '/' on S3, it might not exist yet, but dst.getParent()
// will return null. In this case, use '/' as its own parent to prevent
// NPE errors below.
parent = args.dst;
}
if (!dstfs.exists(parent)) {
dstfs.mkdirs(parent);
}
logPath = new Path(parent, filename);
} else {
logPath = new Path(args.dst, filename);
}
}
FileOutputFormat.setOutputPath(jobConf, logPath);
// create src list, dst list
FileSystem jobfs = jobDirectory.getFileSystem(jobConf);
Path srcfilelist = new Path(jobDirectory, "_distcp_src_files");
jobConf.set(SRC_LIST_LABEL, srcfilelist.toString());
SequenceFile.Writer src_writer = SequenceFile.createWriter(jobfs, jobConf,
srcfilelist, LongWritable.class, FilePair.class,
SequenceFile.CompressionType.NONE);
Path dstfilelist = new Path(jobDirectory, "_distcp_dst_files");
SequenceFile.Writer dst_writer = SequenceFile.createWriter(jobfs, jobConf,
dstfilelist, Text.class, Text.class,
SequenceFile.CompressionType.NONE);
Path dstdirlist = new Path(jobDirectory, "_distcp_dst_dirs");
jobConf.set(DST_DIR_LIST_LABEL, dstdirlist.toString());
SequenceFile.Writer dir_writer = SequenceFile.createWriter(jobfs, jobConf,
dstdirlist, Text.class, FilePair.class,
SequenceFile.CompressionType.NONE);
// handle the case where the destination directory doesn't exist
// and we've only a single src directory OR we're updating/overwriting
// the contents of the destination directory.
final boolean special =
(args.srcs.size() == 1 && !dstExists) || update || overwrite;
int srcCount = 0, cnsyncf = 0, dirsyn = 0;
long fileCount = 0L, dirCount = 0L, byteCount = 0L, cbsyncs = 0L,
skipFileCount = 0L, skipByteCount = 0L;
Path basedir = null;
HashSet<Path> parentDirsToCopy = new HashSet<Path>();
if (args.basedir != null) {
FileSystem basefs = args.basedir.getFileSystem(conf);
basedir = args.basedir.makeQualified(basefs);
if (!basefs.isDirectory(basedir)) {
throw new IOException("Basedir " + basedir + " is not a directory.");
}
}
try {
for(Iterator<Path> srcItr = args.srcs.iterator(); srcItr.hasNext(); ) {
final Path src = srcItr.next();
FileSystem srcfs = src.getFileSystem(conf);
FileStatus srcfilestat = srcfs.getFileStatus(src);
Path root = special && srcfilestat.isDirectory()? src: src.getParent();
if (dstExists && !dstIsDir &&
(args.srcs.size() > 1 || srcfilestat.isDirectory())) {
// destination should not be a file
throw new IOException("Destination " + args.dst + " should be a dir" +
" if multiple source paths are there OR if" +
" the source path is a dir");
}
if (basedir != null) {
root = basedir;
Path parent = src.getParent().makeQualified(srcfs);
while (parent != null && !parent.equals(basedir)) {
if (!parentDirsToCopy.contains(parent)){
parentDirsToCopy.add(parent);
String dst = makeRelative(root, parent);
FileStatus pst = srcfs.getFileStatus(parent);
src_writer.append(new LongWritable(0), new FilePair(pst, dst));
dst_writer.append(new Text(dst), new Text(parent.toString()));
dir_writer.append(new Text(dst), new FilePair(pst, dst));
if (++dirsyn > SYNC_FILE_MAX) {
dirsyn = 0;
dir_writer.sync();
}
}
parent = parent.getParent();
}
if (parent == null) {
throw new IOException("Basedir " + basedir +
" is not a prefix of source path " + src);
}
}
if (srcfilestat.isDirectory()) {
++srcCount;
final String dst = makeRelative(root,src);
if (!update || !dirExists(conf, new Path(args.dst, dst))) {
++dirCount;
src_writer.append(new LongWritable(0),
new FilePair(srcfilestat, dst));
}
dst_writer.append(new Text(dst), new Text(src.toString()));
}
Stack<FileStatus> pathstack = new Stack<FileStatus>();
for(pathstack.push(srcfilestat); !pathstack.empty(); ) {
FileStatus cur = pathstack.pop();
FileStatus[] children = srcfs.listStatus(cur.getPath());
for(int i = 0; i < children.length; i++) {
boolean skipPath = false;
final FileStatus child = children[i];
final String dst = makeRelative(root, child.getPath());
++srcCount;
if (child.isDirectory()) {
pathstack.push(child);
if (!update || !dirExists(conf, new Path(args.dst, dst))) {
++dirCount;
}
else {
skipPath = true; // skip creating dir at destination
}
}
else {
Path destPath = new Path(args.dst, dst);
if (cur.isFile() && (args.srcs.size() == 1)) {
// Copying a single file; use dst path provided by user as
// destination file rather than destination directory
Path dstparent = destPath.getParent();
FileSystem destFileSys = destPath.getFileSystem(jobConf);
if (!(destFileSys.exists(dstparent) &&
destFileSys.getFileStatus(dstparent).isDirectory())) {
destPath = dstparent;
}
}
//skip path if the src and the dst files are the same.
skipPath = update &&
sameFile(srcfs, child, dstfs, destPath, skipCRCCheck);
//skip path if it exceed file limit or size limit
skipPath |= fileCount == args.filelimit
|| byteCount + child.getLen() > args.sizelimit;
if (!skipPath) {
++fileCount;
byteCount += child.getLen();
if (LOG.isTraceEnabled()) {
LOG.trace("adding file " + child.getPath());
}
++cnsyncf;
cbsyncs += child.getLen();
if (cnsyncf > SYNC_FILE_MAX || cbsyncs > maxBytesPerMap) {
src_writer.sync();
dst_writer.sync();
cnsyncf = 0;
cbsyncs = 0L;
}
}
else {
++skipFileCount;
skipByteCount += child.getLen();
if (LOG.isTraceEnabled()) {
LOG.trace("skipping file " + child.getPath());
}
}
}
if (!skipPath) {
src_writer.append(new LongWritable(child.isDirectory()? 0: child.getLen()),
new FilePair(child, dst));
}
dst_writer.append(new Text(dst),
new Text(child.getPath().toString()));
}
if (cur.isDirectory()) {
String dst = makeRelative(root, cur.getPath());
dir_writer.append(new Text(dst), new FilePair(cur, dst));
if (++dirsyn > SYNC_FILE_MAX) {
dirsyn = 0;
dir_writer.sync();
}
}
}
}
} finally {
checkAndClose(src_writer);
checkAndClose(dst_writer);
checkAndClose(dir_writer);
}
LOG.info("sourcePathsCount(files+directories)=" + srcCount);
LOG.info("filesToCopyCount=" + fileCount);
LOG.info("bytesToCopyCount=" + StringUtils.humanReadableInt(byteCount));
if (update) {
LOG.info("filesToSkipCopyCount=" + skipFileCount);
LOG.info("bytesToSkipCopyCount=" +
StringUtils.humanReadableInt(skipByteCount));
}
if (args.dryrun) {
return false;
}
int mapCount = setMapCount(byteCount, jobConf);
// Increase the replication of _distcp_src_files, if needed
setReplication(conf, jobConf, srcfilelist, mapCount);
FileStatus dststatus = null;
try {
dststatus = dstfs.getFileStatus(args.dst);
} catch(FileNotFoundException fnfe) {
LOG.info(args.dst + " does not exist.");
}
// create dest path dir if copying > 1 file
if (dststatus == null) {
if (srcCount > 1 && !dstfs.mkdirs(args.dst)) {
throw new IOException("Failed to create" + args.dst);
}
}
final Path sorted = new Path(jobDirectory, "_distcp_sorted");
checkDuplication(jobfs, dstfilelist, sorted, conf);
if (dststatus != null && args.flags.contains(Options.DELETE)) {
long deletedPathsCount = deleteNonexisting(dstfs, dststatus, sorted,
jobfs, jobDirectory, jobConf, conf);
LOG.info("deletedPathsFromDestCount(files+directories)=" +
deletedPathsCount);
}
Path tmpDir = new Path(
(dstExists && !dstIsDir) || (!dstExists && srcCount == 1)?
args.dst.getParent(): args.dst, "_distcp_tmp_" + randomId);
jobConf.set(TMP_DIR_LABEL, tmpDir.toUri().toString());
// Explicitly create the tmpDir to ensure that it can be cleaned
// up by fullyDelete() later.
tmpDir.getFileSystem(conf).mkdirs(tmpDir);
LOG.info("sourcePathsCount=" + srcCount);
LOG.info("filesToCopyCount=" + fileCount);
LOG.info("bytesToCopyCount=" + StringUtils.humanReadableInt(byteCount));
jobConf.setInt(SRC_COUNT_LABEL, srcCount);
jobConf.setLong(TOTAL_SIZE_LABEL, byteCount);
return (fileCount + dirCount) > 0;
}
/**
* Check whether the contents of src and dst are the same.
*
* Return false if dstpath does not exist
*
* If the files have different sizes, return false.
*
* If the files have the same sizes, the file checksums will be compared.
*
* When file checksum is not supported in any of file systems,
* two files are considered as the same if they have the same size.
*/
static private boolean sameFile(FileSystem srcfs, FileStatus srcstatus,
FileSystem dstfs, Path dstpath, boolean skipCRCCheck) throws IOException {
FileStatus dststatus;
try {
dststatus = dstfs.getFileStatus(dstpath);
} catch(FileNotFoundException fnfe) {
return false;
}
//same length?
if (srcstatus.getLen() != dststatus.getLen()) {
return false;
}
if (skipCRCCheck) {
LOG.debug("Skipping the CRC check");
return true;
}
//get src checksum
final FileChecksum srccs;
try {
srccs = srcfs.getFileChecksum(srcstatus.getPath());
} catch(FileNotFoundException fnfe) {
/*
* Two possible cases:
* (1) src existed once but was deleted between the time period that
* srcstatus was obtained and the try block above.
* (2) srcfs does not support file checksum and (incorrectly) throws
* FNFE, e.g. some previous versions of HftpFileSystem.
* For case (1), it is okay to return true since src was already deleted.
* For case (2), true should be returned.
*/
return true;
}
//compare checksums
try {
final FileChecksum dstcs = dstfs.getFileChecksum(dststatus.getPath());
//return true if checksum is not supported
//(i.e. some of the checksums is null)
return srccs == null || dstcs == null || srccs.equals(dstcs);
} catch(FileNotFoundException fnfe) {
return false;
}
}
/**
* Delete the dst files/dirs which do not exist in src
*
* @return total count of files and directories deleted from destination
* @throws IOException
*/
static private long deleteNonexisting(
FileSystem dstfs, FileStatus dstroot, Path dstsorted,
FileSystem jobfs, Path jobdir, JobConf jobconf, Configuration conf
) throws IOException {
if (dstroot.isFile()) {
throw new IOException("dst must be a directory when option "
+ Options.DELETE.cmd + " is set, but dst (= " + dstroot.getPath()
+ ") is not a directory.");
}
//write dst lsr results
final Path dstlsr = new Path(jobdir, "_distcp_dst_lsr");
final SequenceFile.Writer writer = SequenceFile.createWriter(jobfs, jobconf,
dstlsr, Text.class, NullWritable.class,
SequenceFile.CompressionType.NONE);
try {
//do lsr to get all file statuses in dstroot
final Stack<FileStatus> lsrstack = new Stack<FileStatus>();
for(lsrstack.push(dstroot); !lsrstack.isEmpty(); ) {
final FileStatus status = lsrstack.pop();
if (status.isDirectory()) {
for(FileStatus child : dstfs.listStatus(status.getPath())) {
String relative = makeRelative(dstroot.getPath(), child.getPath());
writer.append(new Text(relative), NullWritable.get());
lsrstack.push(child);
}
}
}
} finally {
checkAndClose(writer);
}
//sort lsr results
final Path sortedlsr = new Path(jobdir, "_distcp_dst_lsr_sorted");
SequenceFile.Sorter sorter = new SequenceFile.Sorter(jobfs,
new Text.Comparator(), Text.class, NullWritable.class, jobconf);
sorter.sort(dstlsr, sortedlsr);
//compare lsr list and dst list
SequenceFile.Reader lsrin = null;
SequenceFile.Reader dstin = null;
long deletedPathsCount = 0;
try {
lsrin = new SequenceFile.Reader(jobfs, sortedlsr, jobconf);
dstin = new SequenceFile.Reader(jobfs, dstsorted, jobconf);
//compare sorted lsr list and sorted dst list
final Text lsrpath = new Text();
final Text dstpath = new Text();
final Text dstfrom = new Text();
final Trash trash = new Trash(dstfs, conf);
Path lastpath = null;
boolean hasnext = dstin.next(dstpath, dstfrom);
while (lsrin.next(lsrpath, NullWritable.get())) {
int dst_cmp_lsr = dstpath.compareTo(lsrpath);
while (hasnext && dst_cmp_lsr < 0) {
hasnext = dstin.next(dstpath, dstfrom);
dst_cmp_lsr = dstpath.compareTo(lsrpath);
}
if (dst_cmp_lsr == 0) {
//lsrpath exists in dst, skip it
hasnext = dstin.next(dstpath, dstfrom);
} else {
//lsrpath does not exist, delete it
final Path rmpath = new Path(dstroot.getPath(), lsrpath.toString());
++deletedPathsCount;
if ((lastpath == null || !isAncestorPath(lastpath, rmpath))) {
if (!(trash.moveToTrash(rmpath) || dstfs.delete(rmpath, true))) {
throw new IOException("Failed to delete " + rmpath);
}
lastpath = rmpath;
}
}
}
} finally {
checkAndClose(lsrin);
checkAndClose(dstin);
}
return deletedPathsCount;
}
//is x an ancestor path of y?
static private boolean isAncestorPath(Path xp, Path yp) {
final String x = xp.toString();
final String y = yp.toString();
if (!y.startsWith(x)) {
return false;
}
final int len = x.length();
return y.length() == len || y.charAt(len) == Path.SEPARATOR_CHAR;
}
/** Check whether the file list have duplication. */
static private void checkDuplication(FileSystem fs, Path file, Path sorted,
Configuration conf) throws IOException {
SequenceFile.Reader in = null;
try {
SequenceFile.Sorter sorter = new SequenceFile.Sorter(fs,
new Text.Comparator(), Text.class, Text.class, conf);
sorter.sort(file, sorted);
in = new SequenceFile.Reader(fs, sorted, conf);
Text prevdst = null, curdst = new Text();
Text prevsrc = null, cursrc = new Text();
for(; in.next(curdst, cursrc); ) {
if (prevdst != null && curdst.equals(prevdst)) {
throw new DuplicationException(
"Invalid input, there are duplicated files in the sources: "
+ prevsrc + ", " + cursrc);
}
prevdst = curdst;
curdst = new Text();
prevsrc = cursrc;
cursrc = new Text();
}
}
finally {
checkAndClose(in);
}
}
static boolean checkAndClose(java.io.Closeable io) {
if (io != null) {
try {
io.close();
}
catch(IOException ioe) {
LOG.warn(StringUtils.stringifyException(ioe));
return false;
}
}
return true;
}
/** An exception class for duplicated source files. */
public static class DuplicationException extends IOException {
private static final long serialVersionUID = 1L;
/** Error code for this exception */
public static final int ERROR_CODE = -2;
DuplicationException(String message) {super(message);}
}
}