co.cask.cdap.internal.app.runtime.LocalizationUtils.java Source code

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Here is the source code for co.cask.cdap.internal.app.runtime.LocalizationUtils.java

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/*
 * Copyright  2015 Cask Data, Inc.
 *
 * Licensed 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 co.cask.cdap.internal.app.runtime;

import co.cask.cdap.common.io.Locations;
import co.cask.cdap.common.lang.jar.BundleJarUtil;
import co.cask.cdap.internal.app.runtime.distributed.LocalizeResource;
import com.google.common.base.Preconditions;
import com.google.common.io.ByteStreams;
import com.google.common.io.Files;
import com.google.common.io.Resources;
import org.apache.commons.compress.archivers.tar.TarArchiveEntry;
import org.apache.commons.compress.archivers.tar.TarArchiveInputStream;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.net.URI;
import java.net.URL;
import java.nio.file.Paths;
import java.util.zip.GZIPInputStream;

/**
 * Utilities for file localization.
 */
public final class LocalizationUtils {
    private static final Logger LOG = LoggerFactory.getLogger(LocalizationUtils.class);

    /**
     * Localizes the specified {@link LocalizeResource} in the specified {@link File targetDir} with the specified
     * file name and returns the {@link File} pointing to the localized file.
     *
     * @param fileName the name to localize the file with
     * @param resource the {@link LocalizeResource} to localize
     * @param targetDir the directory to localize the resource in
     * @return the {@link File} pointing to the localized file.
     */
    public static File localizeResource(String fileName, LocalizeResource resource, File targetDir)
            throws IOException {
        File localizedResource = new File(targetDir, fileName);
        File input = getFileToLocalize(resource, targetDir);
        if (resource.isArchive()) {
            LOG.debug("Decompress file {} to {}", input, localizedResource);
            unpack(input, localizedResource);
        } else {
            try {
                LOG.debug("Hard link file from {} to {}", input, localizedResource);
                java.nio.file.Files.createLink(Paths.get(localizedResource.toURI()), Paths.get(input.toURI()));
            } catch (Exception e) {
                LOG.debug("Copy file from {} to {}", input, localizedResource);
                Files.copy(input, localizedResource);
            }
        }
        return localizedResource;
    }

    /**
     * Returns a local {@link File} for the specified {@link LocalizeResource}. If the specified {@link LocalizeResource}
     * points to a local file already, it simply returns a {@link File} object for it. If it is not local, then the
     * method will try to download the resource to a local temporary file and return it.
     *
     * @param resource the {@link LocalizeResource} for which a local file is requested
     * @param tempDir the {@link File directory} to download the file to if it is a remote file
     * @return a local {@link File} for the specified resource
     */
    private static File getFileToLocalize(LocalizeResource resource, File tempDir) throws IOException {
        URI uri = resource.getURI();
        if ("file".equals(uri.getScheme())) {
            // Local file. Just return a File object for the file.
            return new File(uri.getPath());
        }
        URL url = uri.toURL();
        String name = new File(uri.getPath()).getName();
        File tempFile = new File(tempDir, name);
        Files.copy(Resources.newInputStreamSupplier(url), tempFile);
        return tempFile;
    }

    private static void unpack(File archive, File targetDir) throws IOException {
        if (!targetDir.exists()) {
            //noinspection ResultOfMethodCallIgnored
            targetDir.mkdir();
        }
        String extension = Files.getFileExtension(archive.getPath()).toLowerCase();
        switch (extension) {
        case "zip":
        case "jar":
            BundleJarUtil.unJar(Locations.toLocation(archive), targetDir);
            break;
        case "gz":
            // gz is not recommended for archiving multiple files together. So we only support .tar.gz
            Preconditions.checkArgument(archive.getName().endsWith(".tar.gz"), "'.gz' format is not supported for "
                    + "archiving multiple files. Please use 'zip', 'jar', '.tar.gz', 'tgz' or 'tar'.");
            untargz(archive, targetDir);
            break;
        case "tgz":
            untargz(archive, targetDir);
            break;
        case "tar":
            untar(archive, targetDir);
            break;
        default:
            throw new IllegalArgumentException(
                    String.format("Unsupported compression type '%s'. Only 'zip', 'jar', "
                            + "'tar.gz', 'tgz' and 'tar'  are supported.", extension));
        }
    }

    private static void untar(File tarFile, File targetDir) throws IOException {
        try (TarArchiveInputStream tis = new TarArchiveInputStream(new FileInputStream(tarFile))) {
            extractTar(tis, targetDir);
        }
    }

    private static void untargz(File tarGzFile, File targetDir) throws IOException {
        try (TarArchiveInputStream tis = new TarArchiveInputStream(
                new GZIPInputStream(new FileInputStream(tarGzFile)))) {
            extractTar(tis, targetDir);
        }
    }

    private static void extractTar(final TarArchiveInputStream tis, File targetDir) throws IOException {
        TarArchiveEntry entry = tis.getNextTarEntry();
        while (entry != null) {
            File output = new File(targetDir, new File(entry.getName()).getName());
            if (entry.isDirectory()) {
                //noinspection ResultOfMethodCallIgnored
                output.mkdirs();
            } else {
                //noinspection ResultOfMethodCallIgnored
                output.getParentFile().mkdirs();
                ByteStreams.copy(tis, Files.newOutputStreamSupplier(output));
            }
            entry = tis.getNextTarEntry();
        }
    }

    private LocalizationUtils() {
    }
}