/*
* 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 gobblin.source.extractor.extract.sftp;
import gobblin.configuration.State;
import gobblin.source.extractor.extract.sftp.SftpFsHelper.SftpGetMonitor;
import gobblin.source.extractor.filebased.FileBasedHelperException;
import gobblin.util.HadoopUtils;
import gobblin.util.io.SeekableFSInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URI;
import java.util.List;
import org.apache.commons.io.IOUtils;
import org.apache.commons.lang3.StringUtils;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.BufferedFSInputStream;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.fs.PathFilter;
import org.apache.hadoop.fs.permission.FsPermission;
import org.apache.hadoop.util.Progressable;
import com.google.common.collect.Lists;
import com.jcraft.jsch.Channel;
import com.jcraft.jsch.ChannelExec;
import com.jcraft.jsch.ChannelSftp;
import com.jcraft.jsch.SftpATTRS;
import com.jcraft.jsch.SftpException;
/**
* A {@link FileSystem} implementation that provides the {@link FileSystem} interface for an SFTP server. Uses
* {@link SftpFsHelper} internally to connect to the SFPT server. {@link HadoopUtils#newConfiguration()}
* <ul>
* <li>It is the caller's responsibility to call {@link #close()} on this {@link FileSystem} to disconnect the session.
* <li>Use {@link HadoopUtils#newConfiguration()} when creating a {@link FileSystem} with
* {@link FileSystem#get(Configuration)}. It creates a new {@link SftpLightWeightFileSystem} everytime instead of cached
* copy
* </ul>
*/
public class SftpLightWeightFileSystem extends FileSystem {
private static final URI NAME = URI.create("sftp:///");
private SftpFsHelper fsHelper;
private static final int DEFAULT_BUFFER_SIZE = 32 * 1024;
private static final PathFilter VALID_PATH_FILTER = new PathFilter() {
@Override
public boolean accept(Path path) {
if (path == null) {
return false;
}
if (StringUtils.isBlank(path.toString())) {
return false;
}
if (path.toString().equals(".")) {
return false;
}
if (path.toString().equals("..")) {
return false;
}
return true;
}
};
@Override
public void initialize(URI name, Configuration conf) throws IOException {
super.initialize(name, conf);
State state = HadoopUtils.getStateFromConf(conf);
this.fsHelper = new SftpFsHelper(state);
try {
this.fsHelper.connect();
} catch (FileBasedHelperException e) {
throw new IOException(e);
}
}
@Override
public boolean delete(Path path) throws IOException {
ChannelSftp channel = null;
try {
channel = this.fsHelper.getSftpChannel();
if (getFileStatus(path).isDirectory()) {
channel.rmdir(HadoopUtils.toUriPath(path));
} else {
channel.rm(HadoopUtils.toUriPath(path));
}
} catch (SftpException e) {
throw new IOException(e);
} finally {
safeDisconnect(channel);
}
return true;
}
@Override
public boolean delete(Path path, boolean recursive) throws IOException {
return delete(path);
}
@Override
public FileStatus getFileStatus(Path path) throws IOException {
ChannelSftp channelSftp = null;
ChannelExec channelExec1 = null;
ChannelExec channelExec2 = null;
try {
channelSftp = this.fsHelper.getSftpChannel();
SftpATTRS sftpAttrs = channelSftp.stat(HadoopUtils.toUriPath(path));
FsPermission permission = new FsPermission((short) sftpAttrs.getPermissions());
channelExec1 = this.fsHelper.getExecChannel("id " + sftpAttrs.getUId());
String userName = IOUtils.toString(channelExec1.getInputStream());
channelExec2 = this.fsHelper.getExecChannel("id " + sftpAttrs.getGId());
String groupName = IOUtils.toString(channelExec2.getInputStream());
FileStatus fs =
new FileStatus(sftpAttrs.getSize(), sftpAttrs.isDir(), 1, 0l, sftpAttrs.getMTime(), sftpAttrs.getATime(),
permission, StringUtils.trimToEmpty(userName), StringUtils.trimToEmpty(groupName), path);
return fs;
} catch (SftpException e) {
throw new IOException(e);
} finally {
safeDisconnect(channelSftp);
safeDisconnect(channelExec1);
safeDisconnect(channelExec2);
}
}
@Override
public URI getUri() {
return NAME;
}
@Override
public Path getWorkingDirectory() {
ChannelSftp channelSftp = null;
try {
channelSftp = this.fsHelper.getSftpChannel();
Path workingDir = new Path(channelSftp.pwd());
return workingDir;
} catch (SftpException e) {
return null;
} finally {
safeDisconnect(channelSftp);
}
}
@Override
public FileStatus[] listStatus(Path path) throws IOException {
try {
List<String> fileNames = this.fsHelper.ls(HadoopUtils.toUriPath(path));
List<FileStatus> status = Lists.newArrayListWithCapacity(fileNames.size());
for (String name : fileNames) {
Path filePath = new Path(name);
if (VALID_PATH_FILTER.accept(filePath)) {
status.add(getFileStatus(new Path(path, filePath)));
}
}
return status.toArray(new FileStatus[status.size()]);
} catch (FileBasedHelperException e) {
throw new IOException(e);
}
}
@Override
public boolean mkdirs(Path path, FsPermission permission) throws IOException {
ChannelSftp channel = null;
try {
channel = this.fsHelper.getSftpChannel();
channel.mkdir(HadoopUtils.toUriPath(path));
channel.chmod(permission.toShort(), HadoopUtils.toUriPath(path));
} catch (SftpException e) {
throw new IOException(e);
} finally {
safeDisconnect(channel);
}
return true;
}
@Override
public FSDataInputStream open(Path path, int bufferSize) throws IOException {
SftpGetMonitor monitor = new SftpGetMonitor();
try {
ChannelSftp channelSftp = this.fsHelper.getSftpChannel();
InputStream is = channelSftp.get(HadoopUtils.toUriPath(path), monitor);
return new FSDataInputStream(new BufferedFSInputStream(new SftpFsHelper.SftpFsFileInputStream(is, channelSftp), bufferSize));
} catch (SftpException e) {
throw new IOException(e);
}
}
@Override
public FSDataInputStream open(Path path) throws IOException {
return open(path, DEFAULT_BUFFER_SIZE);
}
@Override
public boolean rename(Path oldPath, Path newPath) throws IOException {
ChannelSftp channelSftp = null;
try {
channelSftp = this.fsHelper.getSftpChannel();
channelSftp.rename(HadoopUtils.toUriPath(oldPath), HadoopUtils.toUriPath(newPath));
} catch (SftpException e) {
throw new IOException(e);
} finally {
safeDisconnect(channelSftp);
}
return true;
}
@Override
public void setWorkingDirectory(Path path) {
ChannelSftp channelSftp = null;
try {
channelSftp = this.fsHelper.getSftpChannel();
channelSftp.lcd(HadoopUtils.toUriPath(path));
} catch (SftpException e) {
throw new RuntimeException("Failed to set working directory", e);
} finally {
safeDisconnect(channelSftp);
}
}
@Override
public void close() {
this.fsHelper.close();
}
@Override
public FSDataOutputStream append(Path arg0, int arg1, Progressable arg2) throws IOException {
throw new UnsupportedOperationException("Not implemented");
}
@Override
public FSDataOutputStream create(Path arg0, FsPermission arg1, boolean arg2, int arg3, short arg4, long arg5,
Progressable arg6) throws IOException {
throw new UnsupportedOperationException("Not implemented");
}
/**
* Null safe disconnect
*/
private static void safeDisconnect(Channel channel) {
if (channel != null) {
channel.disconnect();
}
}
}