/**
* 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.LinkedList;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.fs.PathIsNotDirectoryException;
import com.google.common.base.Preconditions;
/**
* Snapshot related operations
*/
@InterfaceAudience.Private
@InterfaceStability.Unstable
class SnapshotCommands extends FsCommand {
private final static String CREATE_SNAPSHOT = "createSnapshot";
private final static String DELETE_SNAPSHOT = "deleteSnapshot";
private final static String RENAME_SNAPSHOT = "renameSnapshot";
public static void registerCommands(CommandFactory factory) {
factory.addClass(CreateSnapshot.class, "-" + CREATE_SNAPSHOT);
factory.addClass(DeleteSnapshot.class, "-" + DELETE_SNAPSHOT);
factory.addClass(RenameSnapshot.class, "-" + RENAME_SNAPSHOT);
}
/**
* Create a snapshot
*/
public static class CreateSnapshot extends FsCommand {
public static final String NAME = CREATE_SNAPSHOT;
public static final String USAGE = "<snapshotDir> [<snapshotName>]";
public static final String DESCRIPTION = "Create a snapshot on a directory";
private String snapshotName = null;
@Override
protected void processPath(PathData item) throws IOException {
if (!item.stat.isDirectory()) {
throw new PathIsNotDirectoryException(item.toString());
}
}
@Override
protected void processOptions(LinkedList<String> args) throws IOException {
if (args.size() == 0) {
throw new IllegalArgumentException("<snapshotDir> is missing.");
}
if (args.size() > 2) {
throw new IllegalArgumentException("Too many arguements.");
}
if (args.size() == 2) {
snapshotName = args.removeLast();
}
}
@Override
protected void processArguments(LinkedList<PathData> items)
throws IOException {
super.processArguments(items);
if (numErrors != 0) { // check for error collecting paths
return;
}
assert(items.size() == 1);
PathData sroot = items.getFirst();
Path snapshotPath = sroot.fs.createSnapshot(sroot.path, snapshotName);
out.println("Created snapshot " + snapshotPath);
}
}
/**
* Delete a snapshot
*/
public static class DeleteSnapshot extends FsCommand {
public static final String NAME = DELETE_SNAPSHOT;
public static final String USAGE = "<snapshotDir> <snapshotName>";
public static final String DESCRIPTION =
"Delete a snapshot from a directory";
private String snapshotName;
@Override
protected void processPath(PathData item) throws IOException {
if (!item.stat.isDirectory()) {
throw new PathIsNotDirectoryException(item.toString());
}
}
@Override
protected void processOptions(LinkedList<String> args) throws IOException {
if (args.size() != 2) {
throw new IOException("args number not 2: " + args.size());
}
snapshotName = args.removeLast();
}
@Override
protected void processArguments(LinkedList<PathData> items)
throws IOException {
super.processArguments(items);
if (numErrors != 0) { // check for error collecting paths
return;
}
assert (items.size() == 1);
PathData sroot = items.getFirst();
sroot.fs.deleteSnapshot(sroot.path, snapshotName);
}
}
/**
* Rename a snapshot
*/
public static class RenameSnapshot extends FsCommand {
public static final String NAME = RENAME_SNAPSHOT;
public static final String USAGE = "<snapshotDir> <oldName> <newName>";
public static final String DESCRIPTION =
"Rename a snapshot from oldName to newName";
private String oldName;
private String newName;
@Override
protected void processPath(PathData item) throws IOException {
if (!item.stat.isDirectory()) {
throw new PathIsNotDirectoryException(item.toString());
}
}
@Override
protected void processOptions(LinkedList<String> args) throws IOException {
if (args.size() != 3) {
throw new IOException("args number not 3: " + args.size());
}
newName = args.removeLast();
oldName = args.removeLast();
}
@Override
protected void processArguments(LinkedList<PathData> items)
throws IOException {
super.processArguments(items);
if (numErrors != 0) { // check for error collecting paths
return;
}
Preconditions.checkArgument(items.size() == 1);
PathData sroot = items.getFirst();
sroot.fs.renameSnapshot(sroot.path, oldName, newName);
}
}
}