/**
* This file Copyright (c) 2003-2012 Magnolia International
* Ltd. (http://www.magnolia-cms.com). All rights reserved.
*
*
* This file is dual-licensed under both the Magnolia
* Network Agreement and the GNU General Public License.
* You may elect to use one or the other of these licenses.
*
* This file is distributed in the hope that it will be
* useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
* implied warranty of MERCHANTABILITY or FITNESS FOR A
* PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
* Redistribution, except as permitted by whichever of the GPL
* or MNA you select, is prohibited.
*
* 1. For the GPL license (GPL), you can redistribute and/or
* modify this file under the terms of the GNU General
* Public License, Version 3, as published by the Free Software
* Foundation. You should have received a copy of the GNU
* General Public License, Version 3 along with this program;
* if not, write to the Free Software Foundation, Inc., 51
* Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* 2. For the Magnolia Network Agreement (MNA), this file
* and the accompanying materials are made available under the
* terms of the MNA which accompanies this distribution, and
* is available at http://www.magnolia-cms.com/mna.html
*
* Any modifications to this file must keep this entire header
* intact.
*
*/
package info.magnolia.module.files;
import info.magnolia.cms.core.Content;
import info.magnolia.cms.core.HierarchyManager;
import info.magnolia.cms.core.NodeData;
import info.magnolia.cms.util.ContentUtil;
import info.magnolia.cms.util.NodeDataUtil;
import org.apache.commons.codec.binary.Hex;
import javax.jcr.RepositoryException;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.security.DigestInputStream;
import java.security.DigestOutputStream;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
/**
* A FileExtractorOperation which checks extracted files against an MD5 checksum
* stored in the repository. If the checksum does not exist or is identical to the
* file being extracted, the file is extracted and potentially overwrites the
* existing one. If not, which means the file was modified by the user,
* the operation is cancelled.
*
* TODO : what to do with removed files ? should probably be the responsibility of a different Task.
*
*
* @author gjoseph
* @version $Revision: $ ($Author: $)
*/
class MD5CheckingFileExtractorOperation extends BasicFileExtractorOperation {
private final FileExtractionLogger log;
private final HierarchyManager hm;
MD5CheckingFileExtractorOperation(FileExtractionLogger log, HierarchyManager hm, String resourcePath, String absoluteTargetPath) {
super(resourcePath, absoluteTargetPath);
this.log = log;
this.hm = hm;
}
@Override
protected InputStream checkInput() throws IOException {
return wrap(super.checkInput());
}
// TODO : behaviour: overwrite, log, backup, .. ?
@Override
protected File checkOutput() throws IOException {
final File out = super.checkOutput();
if (out.exists()) {
// check md5 of the existing file
final InputStream stream = new FileInputStream(out);
final String existingFileMD5 = calculateMD5(stream);
// check repository md5
final NodeData repoMD5prop = getRepositoryNode().getNodeData("md5");
if (repoMD5prop.isExist()) {
final String repoMD5 = repoMD5prop.getString();
if (existingFileMD5.equals(repoMD5)) {
// resourcePath was found, with correct md5 in repo : repoMD5
return out;
}
log.error("Can't extract " + resourcePath + " as this file was probably modified locally: expected MD5 [" + repoMD5 + "] but current MD5 is [" + existingFileMD5 + "].");
return null;
}
// resourcePath was found, but no md5 found in repo ...
} else {
// resourcePath does not exist yet, extracting ...
}
return out;
}
@Override
protected OutputStream openOutput(File outFile) throws IOException {
final OutputStream outputStream = super.openOutput(outFile);
final MessageDigest md5 = getMessageDigest();
return new DigestOutputStream(outputStream, md5);
}
@Override
protected void copyAndClose(InputStream in, OutputStream out) throws IOException {
super.copyAndClose(in, out);
final DigestInputStream md5Stream = (DigestInputStream) in;
final String newMD5 = retrieveMD5(md5Stream);
try {
NodeDataUtil.getOrCreate(getRepositoryNode(), "md5").setValue(newMD5);
} catch (RepositoryException e) {
throw new RuntimeException(e); // TODO
}
//TODO save .. ?
}
protected Content getRepositoryNode() {
try {
final String repoPath = getRepositoryPath(resourcePath);
final Content node;
if (!hm.isExist(repoPath)) {
node = ContentUtil.createPath(hm, repoPath);
} else {
node = hm.getContent(repoPath);
}
return node;
} catch (RepositoryException e) {
throw new RuntimeException(e); // TODO
}
}
/**
* Returns the path to the node that has the property with this resource's MD5.
* TODO : implement properly + test
*/
protected String getRepositoryPath(String resourcePath) {
return "/server/install" + resourcePath;
}
/**
* Completely reads an InputStream and returns its MD5.
* TODO : should we close it?
*/
protected String calculateMD5(InputStream stream) throws IOException {
final DigestInputStream md5Stream = wrap(stream);
byte[] buffer = new byte[1024];
while (md5Stream.read(buffer) != -1) {
}
return retrieveMD5(md5Stream);
}
protected DigestInputStream wrap(InputStream stream) {
final MessageDigest md5 = getMessageDigest();
return new DigestInputStream(stream, md5);
}
protected String retrieveMD5(DigestInputStream md5Stream) {
final byte[] digInBytes = md5Stream.getMessageDigest().digest();
return String.valueOf(Hex.encodeHex(digInBytes));
}
protected MessageDigest getMessageDigest() {
try {
return MessageDigest.getInstance("MD5");
} catch (NoSuchAlgorithmException e) {
throw new RuntimeException("Can't check files with md5: " + e.getMessage(), e);
}
}
}