/*
* 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.
*/
/**
* This file is based on source code from the Hadoop Project (http://hadoop.apache.org/), licensed by the Apache
* Software Foundation (ASF) under the Apache License, Version 2.0. See the NOTICE file distributed with this work for
* additional information regarding copyright ownership.
*/
package org.apache.flink.core.fs.local;
import org.apache.flink.annotation.Internal;
import org.apache.flink.core.fs.BlockLocation;
import org.apache.flink.core.fs.FSDataInputStream;
import org.apache.flink.core.fs.FSDataOutputStream;
import org.apache.flink.core.fs.FileStatus;
import org.apache.flink.core.fs.FileSystem;
import org.apache.flink.core.fs.Path;
import org.apache.flink.util.OperatingSystem;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.net.InetAddress;
import java.net.URI;
import java.net.UnknownHostException;
import java.nio.file.AccessDeniedException;
import java.nio.file.DirectoryNotEmptyException;
import java.nio.file.FileAlreadyExistsException;
import java.nio.file.Files;
import java.nio.file.NoSuchFileException;
import java.nio.file.StandardCopyOption;
import static org.apache.flink.util.Preconditions.checkNotNull;
/**
* The class {@code LocalFileSystem} is an implementation of the {@link FileSystem} interface
* for the local file system of the machine where the JVM runs.
*/
@Internal
public class LocalFileSystem extends FileSystem {
private static final Logger LOG = LoggerFactory.getLogger(LocalFileSystem.class);
/** The URI representing the local file system. */
private static final URI uri = OperatingSystem.isWindows() ? URI.create("file:/") : URI.create("file:///");
/** Path pointing to the current working directory.
* Because Paths are not immutable, we cannot cache the proper path here */
private final String workingDir;
/** Path pointing to the current working directory.
* Because Paths are not immutable, we cannot cache the proper path here */
private final String homeDir;
/** The host name of this machine */
private final String hostName;
/**
* Constructs a new <code>LocalFileSystem</code> object.
*/
public LocalFileSystem() {
this.workingDir = new Path(System.getProperty("user.dir")).makeQualified(this).toString();
this.homeDir = new Path(System.getProperty("user.home")).toString();
String tmp = "unknownHost";
try {
tmp = InetAddress.getLocalHost().getHostName();
} catch (UnknownHostException e) {
LOG.error("Could not resolve local host", e);
}
this.hostName = tmp;
}
// ------------------------------------------------------------------------
@Override
public BlockLocation[] getFileBlockLocations(FileStatus file, long start, long len) throws IOException {
return new BlockLocation[] {
new LocalBlockLocation(hostName, file.getLen())
};
}
@Override
public FileStatus getFileStatus(Path f) throws IOException {
final File path = pathToFile(f);
if (path.exists()) {
return new LocalFileStatus(pathToFile(f), this);
}
else {
throw new FileNotFoundException("File " + f + " does not exist or the user running "
+ "Flink ('"+System.getProperty("user.name")+"') has insufficient permissions to access it.");
}
}
@Override
public URI getUri() {
return uri;
}
@Override
public Path getWorkingDirectory() {
return new Path(workingDir);
}
@Override
public Path getHomeDirectory() {
return new Path(homeDir);
}
@Override
public void initialize(final URI name) throws IOException {}
@Override
public FSDataInputStream open(final Path f, final int bufferSize) throws IOException {
return open(f);
}
@Override
public FSDataInputStream open(final Path f) throws IOException {
final File file = pathToFile(f);
return new LocalDataInputStream(file);
}
private File pathToFile(Path path) {
if (!path.isAbsolute()) {
path = new Path(getWorkingDirectory(), path);
}
return new File(path.toUri().getPath());
}
@Override
public FileStatus[] listStatus(final Path f) throws IOException {
final File localf = pathToFile(f);
FileStatus[] results;
if (!localf.exists()) {
return null;
}
if (localf.isFile()) {
return new FileStatus[] { new LocalFileStatus(localf, this) };
}
final String[] names = localf.list();
if (names == null) {
return null;
}
results = new FileStatus[names.length];
for (int i = 0; i < names.length; i++) {
results[i] = getFileStatus(new Path(f, names[i]));
}
return results;
}
@Override
public boolean delete(final Path f, final boolean recursive) throws IOException {
final File file = pathToFile(f);
if (file.isFile()) {
return file.delete();
} else if ((!recursive) && file.isDirectory()) {
File[] containedFiles = file.listFiles();
if (containedFiles == null) {
throw new IOException("Directory " + file.toString() + " does not exist or an I/O error occurred");
} else if (containedFiles.length != 0) {
throw new IOException("Directory " + file.toString() + " is not empty");
}
}
return delete(file);
}
/**
* Deletes the given file or directory.
*
* @param f
* the file to be deleted
* @return <code>true</code> if all files were deleted successfully, <code>false</code> otherwise
* @throws IOException
* thrown if an error occurred while deleting the files/directories
*/
private boolean delete(final File f) throws IOException {
if (f.isDirectory()) {
final File[] files = f.listFiles();
for (File file : files) {
final boolean del = delete(file);
if (!del) {
return false;
}
}
} else {
return f.delete();
}
// Now directory is empty
return f.delete();
}
/**
* Recursively creates the directory specified by the provided path.
*
* @return <code>true</code>if the directories either already existed or have been created successfully,
* <code>false</code> otherwise
* @throws IOException
* thrown if an error occurred while creating the directory/directories
*/
@Override
public boolean mkdirs(final Path f) throws IOException {
final File p2f = pathToFile(f);
if(p2f.isDirectory()) {
return true;
}
final Path parent = f.getParent();
return (parent == null || mkdirs(parent)) && (p2f.mkdir() || p2f.isDirectory());
}
@Override
public FSDataOutputStream create(final Path filePath, final WriteMode overwrite) throws IOException {
checkNotNull(filePath, "filePath");
if (exists(filePath) && overwrite == WriteMode.NO_OVERWRITE) {
throw new FileAlreadyExistsException("File already exists: " + filePath);
}
final Path parent = filePath.getParent();
if (parent != null && !mkdirs(parent)) {
throw new IOException("Mkdirs failed to create " + parent);
}
final File file = pathToFile(filePath);
return new LocalDataOutputStream(file);
}
@Override
public FSDataOutputStream create(
Path f, boolean overwrite, int bufferSize, short replication, long blockSize) throws IOException {
return create(f, overwrite ? WriteMode.OVERWRITE : WriteMode.NO_OVERWRITE);
}
@Override
public boolean rename(final Path src, final Path dst) throws IOException {
final File srcFile = pathToFile(src);
final File dstFile = pathToFile(dst);
final File dstParent = dstFile.getParentFile();
// Files.move fails if the destination directory doesn't exist
//noinspection ResultOfMethodCallIgnored -- we don't care if the directory existed or was created
dstParent.mkdirs();
try {
Files.move(srcFile.toPath(), dstFile.toPath(), StandardCopyOption.REPLACE_EXISTING);
return true;
}
catch (NoSuchFileException | AccessDeniedException | DirectoryNotEmptyException | SecurityException ex) {
// catch the errors that are regular "move failed" exceptions and return false
return false;
}
}
@Override
public boolean isDistributedFS() {
return false;
}
}