com.google.jenkins.plugins.persistentmaster.volume.zip.ZipCreator.java Source code

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Here is the source code for com.google.jenkins.plugins.persistentmaster.volume.zip.ZipCreator.java

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/*
 * Copyright 2014 Google Inc. All Rights Reserved.
 *
 * 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 com.google.jenkins.plugins.persistentmaster.volume.zip;

import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.StandardOpenOption;
import java.nio.file.attribute.BasicFileAttributes;
import java.util.logging.Logger;
import javax.annotation.Nullable;

import org.apache.commons.compress.archivers.zip.UnixStat;
import org.apache.commons.compress.archivers.zip.Zip64Mode;
import org.apache.commons.compress.archivers.zip.ZipArchiveEntry;
import org.apache.commons.compress.archivers.zip.ZipArchiveOutputStream;

import com.google.common.base.Preconditions;
import com.google.jenkins.plugins.persistentmaster.volume.Volume;

/**
 * Implementation of {@link Volume.Creator} for ZIP volumes.
 */
class ZipCreator implements Volume.Creator {

    private static final Logger logger = Logger.getLogger(ZipCreator.class.getName());

    private static final String UTF_8 = "UTF-8";

    private final ZipArchiveOutputStream zipStream;
    private final Path zipPath;
    private boolean closed = false;
    private int fileCount = 0;

    ZipCreator(Path zip) throws IOException {
        zipPath = Preconditions.checkNotNull(zip);
        Preconditions.checkArgument(!Files.exists(zipPath), "zip file exists");
        logger.finer("Creating zip volume for path: " + zipPath);
        zipStream = new ZipArchiveOutputStream(Files.newOutputStream(zipPath, StandardOpenOption.CREATE_NEW));
        // unfortunately there is no typesafe way of doing this
        zipStream.setEncoding(UTF_8);
        zipStream.setUseZip64(Zip64Mode.AsNeeded);
    }

    @Override
    public void addFile(Path file, String pathInVolume, @Nullable BasicFileAttributes attrs) throws IOException {
        Preconditions.checkState(!closed, "Volume closed");
        if (attrs == null) { // make sure attrs are available
            attrs = Files.readAttributes(file, BasicFileAttributes.class);
        }
        if (attrs.isSymbolicLink()) {
            copySymlink(file, pathInVolume);
        } else if (attrs.isDirectory()) {
            copyDirectory(pathInVolume);
        } else {
            copyRegularFile(file, pathInVolume);
        }
        fileCount++;
    }

    private void copySymlink(Path file, String filenameInZip) throws IOException {
        logger.finer("Adding symlink: " + file + " with filename: " + filenameInZip);
        Path symlinkTarget = Files.readSymbolicLink(file);
        // Unfortunately, there is no API method to create a symlink in a ZIP file,
        // however, a symlink entry can easily be created by hand.
        // The requirements for a symlink entry are:
        //  - the unix mode must have the LINK_FLAG set
        //  - the content must contain the target of the symlink as UTF8 string
        ZipArchiveEntry entry = new ZipArchiveEntry(filenameInZip);
        entry.setUnixMode(entry.getUnixMode() | UnixStat.LINK_FLAG);
        zipStream.putArchiveEntry(entry);
        zipStream.write(symlinkTarget.toString().getBytes(StandardCharsets.UTF_8));
        zipStream.closeArchiveEntry();
    }

    private void copyDirectory(String filenameInZip) throws IOException {
        logger.finer("Adding directory: " + filenameInZip);
        // entries ending in / indicate a directory
        ZipArchiveEntry entry = new ZipArchiveEntry(filenameInZip + "/");
        // in addition, set the unix directory flag
        entry.setUnixMode(entry.getUnixMode() | UnixStat.DIR_FLAG);
        zipStream.putArchiveEntry(entry);
        zipStream.closeArchiveEntry();
    }

    private void copyRegularFile(Path file, String filenameInZip) throws IOException {
        logger.finer("Adding file: " + file + " with filename: " + filenameInZip);
        ZipArchiveEntry entry = new ZipArchiveEntry(filenameInZip);
        zipStream.putArchiveEntry(entry);
        Files.copy(file, zipStream);
        zipStream.closeArchiveEntry();
    }

    @Override
    public int getFileCount() {
        return fileCount;
    }

    @Override
    public void close() throws IOException {
        Preconditions.checkState(!closed, "Volume already closed");
        logger.finer("Closing zip creator for path: " + zipPath);
        zipStream.close();
        closed = true;
    }

}