org.apache.hadoop.fs.shell.CopyCommands 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.fs.shell;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.fs.PathIsDirectoryException;
import org.apache.hadoop.io.IOUtils;
/** Various commands for copy files */
@InterfaceAudience.Private
@InterfaceStability.Evolving
class CopyCommands {
public static void registerCommands(CommandFactory factory) {
factory.addClass(Merge.class, "-getmerge");
factory.addClass(Cp.class, "-cp");
factory.addClass(CopyFromLocal.class, "-copyFromLocal");
factory.addClass(CopyToLocal.class, "-copyToLocal");
factory.addClass(Get.class, "-get");
factory.addClass(Put.class, "-put");
factory.addClass(AppendToFile.class, "-appendToFile");
}
/** merge multiple files together */
public static class Merge extends FsCommand {
public static final String NAME = "getmerge";
public static final String USAGE = "[-nl] ";
public static final String DESCRIPTION =
"Get all the files in the directories that " +
"match the source file pattern and merge and sort them to only " +
"one file on local fs. is kept.\n" +
"-nl: Add a newline character at the end of each file.";
protected PathData dst = null;
protected String delimiter = null;
protected List srcs = null;
@Override
protected void processOptions(LinkedList args) throws IOException {
try {
CommandFormat cf = new CommandFormat(2, Integer.MAX_VALUE, "nl");
cf.parse(args);
delimiter = cf.getOpt("nl") ? "\n" : null;
dst = new PathData(new URI(args.removeLast()), getConf());
if (dst.exists && dst.stat.isDirectory()) {
throw new PathIsDirectoryException(dst.toString());
}
srcs = new LinkedList();
} catch (URISyntaxException e) {
throw new IOException("unexpected URISyntaxException", e);
}
}
@Override
protected void processArguments(LinkedList items)
throws IOException {
super.processArguments(items);
if (exitCode != 0) { // check for error collecting paths
return;
}
FSDataOutputStream out = dst.fs.create(dst.path);
try {
for (PathData src : srcs) {
FSDataInputStream in = src.fs.open(src.path);
try {
IOUtils.copyBytes(in, out, getConf(), false);
if (delimiter != null) {
out.write(delimiter.getBytes("UTF-8"));
}
} finally {
in.close();
}
}
} finally {
out.close();
}
}
@Override
protected void processNonexistentPath(PathData item) throws IOException {
exitCode = 1; // flag that a path is bad
super.processNonexistentPath(item);
}
// this command is handled a bit differently than others. the paths
// are batched up instead of actually being processed. this avoids
// unnecessarily streaming into the merge file and then encountering
// a path error that should abort the merge
@Override
protected void processPath(PathData src) throws IOException {
// for directories, recurse one level to get its files, else skip it
if (src.stat.isDirectory()) {
if (getDepth() == 0) {
recursePath(src);
} // skip subdirs
} else {
srcs.add(src);
}
}
}
static class Cp extends CommandWithDestination {
public static final String NAME = "cp";
public static final String USAGE = "[-f] [-p | -p[topax]] ... ";
public static final String DESCRIPTION =
"Copy files that match the file pattern to a " +
"destination. When copying multiple files, the destination " +
"must be a directory. Passing -p preserves status " +
"[topax] (timestamps, ownership, permission, ACLs, XAttr). " +
"If -p is specified with no , then preserves " +
"timestamps, ownership, permission. If -pa is specified, " +
"then preserves permission also because ACL is a super-set of " +
"permission. Passing -f overwrites the destination if it " +
"already exists. raw namespace extended attributes are preserved " +
"if (1) they are supported (HDFS only) and, (2) all of the source and " +
"target pathnames are in the /.reserved/raw hierarchy. raw namespace " +
"xattr preservation is determined solely by the presence (or absence) " +
"of the /.reserved/raw prefix and not by the -p option.\n";
@Override
protected void processOptions(LinkedList args) throws IOException {
popPreserveOption(args);
CommandFormat cf = new CommandFormat(2, Integer.MAX_VALUE, "f");
cf.parse(args);
setOverwrite(cf.getOpt("f"));
// should have a -r option
setRecursive(true);
getRemoteDestination(args);
}
private void popPreserveOption(List args) {
for (Iterator iter = args.iterator(); iter.hasNext(); ) {
String cur = iter.next();
if (cur.equals("--")) {
// stop parsing arguments when you see --
break;
} else if (cur.startsWith("-p")) {
iter.remove();
if (cur.length() == 2) {
setPreserve(true);
} else {
String attributes = cur.substring(2);
for (int index = 0; index < attributes.length(); index++) {
preserve(FileAttribute.getAttribute(attributes.charAt(index)));
}
}
return;
}
}
}
}
/**
* Copy local files to a remote filesystem
*/
public static class Get extends CommandWithDestination {
public static final String NAME = "get";
public static final String USAGE =
"[-p] [-ignoreCrc] [-crc] ... ";
public static final String DESCRIPTION =
"Copy files that match the file pattern " +
"to the local name. is kept. When copying multiple " +
"files, the destination must be a directory. Passing " +
"-p preserves access and modification times, " +
"ownership and the mode.\n";
@Override
protected void processOptions(LinkedList args)
throws IOException {
CommandFormat cf = new CommandFormat(
1, Integer.MAX_VALUE, "crc", "ignoreCrc", "p");
cf.parse(args);
setWriteChecksum(cf.getOpt("crc"));
setVerifyChecksum(!cf.getOpt("ignoreCrc"));
setPreserve(cf.getOpt("p"));
setRecursive(true);
getLocalDestination(args);
}
}
/**
* Copy local files to a remote filesystem
*/
public static class Put extends CommandWithDestination {
public static final String NAME = "put";
public static final String USAGE = "[-f] [-p] [-l] ... ";
public static final String DESCRIPTION =
"Copy files from the local file system " +
"into fs. Copying fails if the file already " +
"exists, unless the -f flag is given.\n" +
"Flags:\n" +
" -p : Preserves access and modification times, ownership and the mode.\n" +
" -f : Overwrites the destination if it already exists.\n" +
" -l : Allow DataNode to lazily persist the file to disk. Forces\n" +
" replication factor of 1. This flag will result in reduced\n" +
" durability. Use with care.\n";
@Override
protected void processOptions(LinkedList args) throws IOException {
CommandFormat cf = new CommandFormat(1, Integer.MAX_VALUE, "f", "p", "l");
cf.parse(args);
setOverwrite(cf.getOpt("f"));
setPreserve(cf.getOpt("p"));
setLazyPersist(cf.getOpt("l"));
getRemoteDestination(args);
// should have a -r option
setRecursive(true);
}
// commands operating on local paths have no need for glob expansion
@Override
protected List expandArgument(String arg) throws IOException {
List items = new LinkedList();
try {
items.add(new PathData(new URI(arg), getConf()));
} catch (URISyntaxException e) {
if (Path.WINDOWS) {
// Unlike URI, PathData knows how to parse Windows drive-letter paths.
items.add(new PathData(arg, getConf()));
} else {
throw new IOException("unexpected URISyntaxException", e);
}
}
return items;
}
@Override
protected void processArguments(LinkedList args)
throws IOException {
// NOTE: this logic should be better, mimics previous implementation
if (args.size() == 1 && args.get(0).toString().equals("-")) {
copyStreamToTarget(System.in, getTargetPath(args.get(0)));
return;
}
super.processArguments(args);
}
}
public static class CopyFromLocal extends Put {
public static final String NAME = "copyFromLocal";
public static final String USAGE = Put.USAGE;
public static final String DESCRIPTION = "Identical to the -put command.";
}
public static class CopyToLocal extends Get {
public static final String NAME = "copyToLocal";
public static final String USAGE = Get.USAGE;
public static final String DESCRIPTION = "Identical to the -get command.";
}
/**
* Append the contents of one or more local files to a remote
* file.
*/
public static class AppendToFile extends CommandWithDestination {
public static final String NAME = "appendToFile";
public static final String USAGE = " ... ";
public static final String DESCRIPTION =
"Appends the contents of all the given local files to the " +
"given dst file. The dst file will be created if it does " +
"not exist. If is -, then the input is read " +
"from stdin.";
private static final int DEFAULT_IO_LENGTH = 1024 * 1024;
boolean readStdin = false;
// commands operating on local paths have no need for glob expansion
@Override
protected List expandArgument(String arg) throws IOException {
List items = new LinkedList();
if (arg.equals("-")) {
readStdin = true;
} else {
try {
items.add(new PathData(new URI(arg), getConf()));
} catch (URISyntaxException e) {
if (Path.WINDOWS) {
// Unlike URI, PathData knows how to parse Windows drive-letter paths.
items.add(new PathData(arg, getConf()));
} else {
throw new IOException("Unexpected URISyntaxException: " + e.toString());
}
}
}
return items;
}
@Override
protected void processOptions(LinkedList args)
throws IOException {
if (args.size() < 2) {
throw new IOException("missing destination argument");
}
getRemoteDestination(args);
super.processOptions(args);
}
@Override
protected void processArguments(LinkedList args)
throws IOException {
if (!dst.exists) {
dst.fs.create(dst.path, false).close();
}
InputStream is = null;
FSDataOutputStream fos = dst.fs.append(dst.path);
try {
if (readStdin) {
if (args.size() == 0) {
IOUtils.copyBytes(System.in, fos, DEFAULT_IO_LENGTH);
} else {
throw new IOException(
"stdin (-) must be the sole input argument when present");
}
}
// Read in each input file and write to the target.
for (PathData source : args) {
is = new FileInputStream(source.toFile());
IOUtils.copyBytes(is, fos, DEFAULT_IO_LENGTH);
IOUtils.closeStream(is);
is = null;
}
} finally {
if (is != null) {
IOUtils.closeStream(is);
}
if (fos != null) {
IOUtils.closeStream(fos);
}
}
}
}
}
© 2015 - 2024 Weber Informatics LLC | Privacy Policy