org.apache.tika.parser.utils.ZipSalvager Maven / Gradle / Ivy
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* 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.tika.parser.utils;
import java.io.EOFException;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.nio.file.Files;
import java.util.zip.ZipException;
import org.apache.commons.compress.archivers.zip.ZipArchiveEntry;
import org.apache.commons.compress.archivers.zip.ZipArchiveInputStream;
import org.apache.commons.compress.archivers.zip.ZipArchiveOutputStream;
import org.apache.tika.io.IOUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class ZipSalvager {
private static final Logger LOG = LoggerFactory.getLogger(ZipSalvager.class);
/**
* This streams the broken zip and rebuilds a new zip that
* is at least a valid zip file. The contents of the final stream
* may be truncated, but the result should be a valid zip file.
*
* This does nothing fancy to fix the underlying broken zip.
*
* @param brokenZip
* @param salvagedZip
*/
public static void salvageCopy(InputStream brokenZip, File salvagedZip) {
try (ZipArchiveOutputStream outputStream = new ZipArchiveOutputStream(salvagedZip)) {
ZipArchiveInputStream zipArchiveInputStream = new ZipArchiveInputStream(brokenZip);
ZipArchiveEntry zae = zipArchiveInputStream.getNextZipEntry();
while (zae != null) {
try {
if (!zae.isDirectory() && zipArchiveInputStream.canReadEntryData(zae)) {
//create a new ZAE and copy over only the name so that
//if there is bad info (e.g. CRC) in brokenZip's zae, that
//won't be propagated or cause an exception
outputStream.putArchiveEntry(new ZipArchiveEntry(zae.getName()));
//this will copy an incomplete stream...so there
//could be truncation of the xml/contents, but the zip file
//should be intact.
boolean successfullyCopied = false;
try {
IOUtils.copy(zipArchiveInputStream, outputStream);
successfullyCopied = true;
} catch (IOException e) {
//this can hit a "truncated ZipFile" IOException
}
outputStream.flush();
outputStream.closeArchiveEntry();
if (!successfullyCopied) {
break;
}
}
zae = zipArchiveInputStream.getNextZipEntry();
} catch (ZipException | EOFException e) {
break;
}
}
outputStream.flush();
outputStream.finish();
} catch (IOException e) {
LOG.warn("problem fixing zip", e);
}
}
public static void salvageCopy(File brokenZip, File salvagedZip) throws IOException {
try (InputStream is = Files.newInputStream(brokenZip.toPath())) {
salvageCopy(is, salvagedZip);
}
}
}