/**
* 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.IOException;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.Locale;
import java.util.Map;
import java.util.Map.Entry;
import com.google.common.base.Enums;
import com.google.common.base.Function;
import com.google.common.base.Preconditions;
import org.apache.hadoop.HadoopIllegalArgumentException;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.fs.XAttrCodec;
import org.apache.hadoop.util.StringUtils;
/**
* XAttr related operations
*/
@InterfaceAudience.Private
@InterfaceStability.Evolving
class XAttrCommands extends FsCommand {
private static final String GET_FATTR = "getfattr";
private static final String SET_FATTR = "setfattr";
public static void registerCommands(CommandFactory factory) {
factory.addClass(GetfattrCommand.class, "-" + GET_FATTR);
factory.addClass(SetfattrCommand.class, "-" + SET_FATTR);
}
/**
* Implements the '-getfattr' command for the FsShell.
*/
public static class GetfattrCommand extends FsCommand {
public static final String NAME = GET_FATTR;
public static final String USAGE = "[-R] {-n name | -d} [-e en] <path>";
public static final String DESCRIPTION =
"Displays the extended attribute names and values (if any) for a " +
"file or directory.\n" +
"-R: Recursively list the attributes for all files and directories.\n" +
"-n name: Dump the named extended attribute value.\n" +
"-d: Dump all extended attribute values associated with pathname.\n" +
"-e <encoding>: Encode values after retrieving them." +
"Valid encodings are \"text\", \"hex\", and \"base64\". " +
"Values encoded as text strings are enclosed in double quotes (\")," +
" and values encoded as hexadecimal and base64 are prefixed with " +
"0x and 0s, respectively.\n" +
"<path>: The file or directory.\n";
private final static Function<String, XAttrCodec> enValueOfFunc =
Enums.valueOfFunction(XAttrCodec.class);
private String name = null;
private boolean dump = false;
private XAttrCodec encoding = XAttrCodec.TEXT;
@Override
protected void processOptions(LinkedList<String> args) throws IOException {
name = StringUtils.popOptionWithArgument("-n", args);
String en = StringUtils.popOptionWithArgument("-e", args);
if (en != null) {
try {
encoding = enValueOfFunc.apply(StringUtils.toUpperCase(en));
} catch (IllegalArgumentException e) {
throw new IllegalArgumentException(
"Invalid/unsupported encoding option specified: " + en);
}
Preconditions.checkArgument(encoding != null,
"Invalid/unsupported encoding option specified: " + en);
}
boolean r = StringUtils.popOption("-R", args);
setRecursive(r);
dump = StringUtils.popOption("-d", args);
if (!dump && name == null) {
throw new HadoopIllegalArgumentException(
"Must specify '-n name' or '-d' option.");
}
if (args.isEmpty()) {
throw new HadoopIllegalArgumentException("<path> is missing.");
}
if (args.size() > 1) {
throw new HadoopIllegalArgumentException("Too many arguments.");
}
}
@Override
protected void processPath(PathData item) throws IOException {
out.println("# file: " + item);
if (dump) {
Map<String, byte[]> xattrs = item.fs.getXAttrs(item.path);
if (xattrs != null) {
Iterator<Entry<String, byte[]>> iter = xattrs.entrySet().iterator();
while(iter.hasNext()) {
Entry<String, byte[]> entry = iter.next();
printXAttr(entry.getKey(), entry.getValue());
}
}
} else {
byte[] value = item.fs.getXAttr(item.path, name);
printXAttr(name, value);
}
}
private void printXAttr(String name, byte[] value) throws IOException{
if (value != null) {
if (value.length != 0) {
out.println(name + "=" + XAttrCodec.encodeValue(value, encoding));
} else {
out.println(name);
}
}
}
}
/**
* Implements the '-setfattr' command for the FsShell.
*/
public static class SetfattrCommand extends FsCommand {
public static final String NAME = SET_FATTR;
public static final String USAGE = "{-n name [-v value] | -x name} <path>";
public static final String DESCRIPTION =
"Sets an extended attribute name and value for a file or directory.\n" +
"-n name: The extended attribute name.\n" +
"-v value: The extended attribute value. There are three different " +
"encoding methods for the value. If the argument is enclosed in double " +
"quotes, then the value is the string inside the quotes. If the " +
"argument is prefixed with 0x or 0X, then it is taken as a hexadecimal " +
"number. If the argument begins with 0s or 0S, then it is taken as a " +
"base64 encoding.\n" +
"-x name: Remove the extended attribute.\n" +
"<path>: The file or directory.\n";
private String name = null;
private byte[] value = null;
private String xname = null;
@Override
protected void processOptions(LinkedList<String> args) throws IOException {
name = StringUtils.popOptionWithArgument("-n", args);
String v = StringUtils.popOptionWithArgument("-v", args);
if (v != null) {
value = XAttrCodec.decodeValue(v);
}
xname = StringUtils.popOptionWithArgument("-x", args);
if (name != null && xname != null) {
throw new HadoopIllegalArgumentException(
"Can not specify both '-n name' and '-x name' option.");
}
if (name == null && xname == null) {
throw new HadoopIllegalArgumentException(
"Must specify '-n name' or '-x name' option.");
}
if (args.isEmpty()) {
throw new HadoopIllegalArgumentException("<path> is missing.");
}
if (args.size() > 1) {
throw new HadoopIllegalArgumentException("Too many arguments.");
}
}
@Override
protected void processPath(PathData item) throws IOException {
if (name != null) {
item.fs.setXAttr(item.path, name, value);
} else if (xname != null) {
item.fs.removeXAttr(item.path, xname);
}
}
}
}