/**
* Copyright (C) 2012-2013 Selventa, Inc.
*
* This file is part of the OpenBEL Framework.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* The OpenBEL Framework is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
* License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with the OpenBEL Framework. If not, see <http://www.gnu.org/licenses/>.
*
* Additional Terms under LGPL v3:
*
* This license does not authorize you and you are prohibited from using the
* name, trademarks, service marks, logos or similar indicia of Selventa, Inc.,
* or, in the discretion of other licensors or authors of the program, the
* name, trademarks, service marks, logos or similar indicia of such authors or
* licensors, in any marketing or advertising materials relating to your
* distribution of the program or any covered product. This restriction does
* not waive or limit your obligation to keep intact all copyright notices set
* forth in the program as delivered to you.
*
* If you distribute the program in whole or in part, or any modified version
* of the program, and you assume contractual liability to the recipient with
* respect to the program or modified version, then you will indemnify the
* authors and licensors of the program for any liabilities that these
* contractual assumptions directly impose on those licensors and authors.
*/
package org.openbel.framework.core.df.cache;
import static org.apache.commons.io.FileUtils.copyFile;
import static org.apache.commons.io.FileUtils.readFileToString;
import static org.apache.commons.io.FileUtils.write;
import static org.apache.commons.io.IOUtils.closeQuietly;
import static org.openbel.framework.common.BELUtilities.createDirectories;
import static org.openbel.framework.common.BELUtilities.nulls;
import static org.openbel.framework.common.PathConstants.SHA256_EXTENSION;
import static org.openbel.framework.common.Strings.UTF_8;
import static org.openbel.framework.common.cfg.SystemConfiguration.getSystemConfiguration;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.zip.GZIPInputStream;
import org.apache.commons.io.filefilter.MagicNumberFileFilter;
import org.openbel.framework.common.InvalidArgument;
import org.openbel.framework.common.cfg.SystemConfiguration;
import org.openbel.framework.common.util.Hasher;
import org.openbel.framework.core.protocol.ResourceDownloadError;
import org.openbel.framework.core.protocol.ResourceResolver;
/**
* Static utility methods for dealing with the BELFramework cache.
*
* @author Anthony Bargnesi {@code <abargnesi@selventa.com>}
*/
public class CacheUtil {
/**
* Prevent construction of static utility class.
*/
private CacheUtil() {
}
/**
* Defines the gzip magic number.
*/
private static final byte[] GZIP_MAGIC_NUMBER = new byte[] {
(byte) 0x1f,
(byte) 0x8b };
/**
* Defines the static resource resolver instance to use in
* {@link CacheUtil#resolveResource(String, String, String)}.
*/
private static final ResourceResolver resolver = new ResourceResolver();
/**
* Defines the singleton {@link Hasher} to use when hashing locally cached
* files.
*/
private static final Hasher hasher = Hasher.INSTANCE;
/**
* Resolves a resource location to a local path.
*
* @param resourceLocation {@link String}, the resource location that
* defines where to pull the file, which cannot be null
* @param localPath {@link String}, the local path to store the resource
* at, which cannot be null
* @param localFileName {@link String}, the local file name to store the
* resource as, which cannot be null
* @return {@link File}, the resource resolved to a local file
* @throws ResourceDownloadError Thrown if a resource download error
* occurred while resolving the resource location
* @throw {@link InvalidArgument} Thrown if any arguments are null
*/
public static File resolveResource(String resourceLocation,
String localPath,
String localFileName)
throws ResourceDownloadError {
if (nulls(resourceLocation, localPath, localFileName)) {
throw new InvalidArgument("null argument(s) provided");
}
createDirectories(localPath);
StringBuilder builder = new StringBuilder();
builder.append(localPath).append(File.separator).append(localFileName);
// resolve resource
File resourceFile = resolver.resolveResource(resourceLocation,
builder.toString());
return resourceFile;
}
/**
* Download the resource and hash the contents using {@link Hasher}.
*
* @param remoteLocation {@link String}, the remote resource location
* @param type {@link ResourceType}, the resource type
* @return {@link File} the downloaded resource file, decompressed if the
* file is in GZIP format
* @throws ResourceDownloadError Thrown if the remote resource could not
* be downloaded
* @throws IOException Thrown if an IO error occurred while handling the
* resources
*/
public static File
downloadResource(String remoteLocation, ResourceType type)
throws ResourceDownloadError {
String localResourcePath = getResourceFolderPath(type) + File.separator
+ encodeLocation(remoteLocation);
String localResourceLocation =
CacheLookupService.DEFAULT_RESOURCE_FILE_NAME
+ type.getResourceExtension();
File latestResource = resolveResource(remoteLocation,
localResourcePath, localResourceLocation);
// attempt to download resource hash
String remoteHashLocation = remoteLocation + SHA256_EXTENSION;
String localHashLocation = localResourceLocation + SHA256_EXTENSION;
try {
resolveResource(remoteHashLocation, localResourcePath,
localHashLocation);
} catch (ResourceDownloadError e) {
// remote hash does not exist but create local hash
createLocalHash(latestResource, remoteLocation);
}
return latestResource;
}
/**
* Returns the absolute path for the sub-directory resource folder using
* the cache directory provided by
* {@link SystemConfiguration#getCacheDirectory()}.
*
* <p>
* If the sub-directory resource folder does not exist it will be created.
* </p>
*
* <p>
* If the {@link SystemConfiguration} object's cache directory does not
* exist or the {@link SystemConfiguration} has not been created then an
* {@link IllegalStateException} will be thrown.
* </p>
*
* @return {@link String}, the absolute path for the sub-directory resource
* folder
* @throws IllegalStateException Thrown if the {@link SystemConfiguration}
* object's cache directory does not exist, is not readable, is not writable,
* or if the {@link SystemConfiguration} has not been created yet.
*/
public static String getResourceFolderPath(ResourceType type) {
String cachePath = getSystemConfiguration().getCacheDirectory()
.getAbsolutePath();
File cacheDir = new File(cachePath);
if (!cacheDir.exists()) {
throw new IllegalStateException(
"The system configuration's cache directory - "
+ cacheDir.getAbsolutePath() + " - does not exist.");
}
if (!cacheDir.canRead()) {
throw new IllegalStateException(
"The system configuration's cache directory - "
+ cacheDir.getAbsolutePath()
+ " - is not readable.");
}
if (!cacheDir.canWrite()) {
throw new IllegalStateException(
"The system configuration's cache directory - "
+ cacheDir.getAbsolutePath()
+ " - is not writable.");
}
StringBuilder resourceFolderPath = new StringBuilder();
resourceFolderPath.append(cachePath);
if (!cachePath.endsWith("/")) {
resourceFolderPath.append(File.separator);
}
resourceFolderPath.append(type.getResourceFolderName());
return resourceFolderPath.toString();
}
/**
* Creates a hash of the contents of the {@link File} <tt>resource</tt> and
* writes it to a file alongside the real resource file. The hash file
* can be found by appending {@link ResourceType#SHA256_EXTENSION} to the
* resource path.
*
* @param resource {@link File}, the local resource file
* @param remoteLocation {@link String}, the remote resource location
* @return {@link File}, the local hash file that was created
* @throws IOException Thrown if there was an IO error reading the local
* resource file, or writing the local hash file
* @throws ResourceDownloadError
*/
public static File createLocalHash(File resource, String remoteLocation)
throws ResourceDownloadError {
File localHashFile;
try {
String contents = readFileToString(resource);
String hashValue = hasher.hashValue(contents);
String absPath = resource.getAbsolutePath();
String localHashPath = absPath + SHA256_EXTENSION;
localHashFile = new File(localHashPath);
write(localHashFile, hashValue, UTF_8);
return localHashFile;
} catch (IOException e) {
throw new ResourceDownloadError(remoteLocation, e.getMessage());
}
}
/**
* Encodes the resource location as a one-way SHA256 hash.
*
* @param location {@link String}, the resource location
* @return {@link String} the SHA256 hash of the resource location
*/
public static String encodeLocation(String location) {
return hasher.hashValue(location);
}
/**
* Copies the resolved resource to the system's temporary directory pointed
* to by the system property <tt>java.io.tmpdir</tt>.
* <p>
* GZIP Decompression occur on the file if the cached resource is found to
* contain the {@link #GZIP_MAGIC_NUMBER}. See
* {@link CacheUtil#copyWithDecompression(File, String, File)}.
* </p>
*
* @param resource {@link File}, the resource file to copy from
* @param resourceLocation {@link String}, the resource location url
* @param copy {@link File}, the resource file to copy to
* @return {@link File}, the resource file in the system's temp directory
* @throws ResourceDownloadError Thrown if an IO error copying the resource
*/
public static File copyToDirectory(File resource,
final String resourceLocation, final File copy)
throws ResourceDownloadError {
copy.getParentFile().mkdirs();
return copyWithDecompression(resource, resourceLocation, copy);
}
/**
* Copies the <tt>resource</tt> to <tt>copy</tt>. Decompression is
* performed if the resource file is identified as a GZIP-encoded file.
*
* @param resource {@link File}, the resource to copy
* @param resourceLocation {@link String}, the resource location url
* @param copy {@link File}, the file to copy to
* @return {@link File}, the copied file
* @throws ResourceDownloadError Thrown if an IO error copying the resource
*/
private static File copyWithDecompression(final File resource,
final String resourceLocation, final File copy)
throws ResourceDownloadError {
GZIPInputStream gzipis = null;
FileOutputStream fout = null;
try {
MagicNumberFileFilter mnff = new MagicNumberFileFilter(
GZIP_MAGIC_NUMBER);
if (mnff.accept(resource)) {
gzipis = new GZIPInputStream(new FileInputStream(
resource));
byte[] buffer = new byte[8192];
fout = new FileOutputStream(copy);
int length;
while ((length = gzipis.read(buffer, 0, 8192)) != -1) {
fout.write(buffer, 0, length);
}
} else {
copyFile(resource, copy);
}
} catch (IOException e) {
String msg = e.getMessage();
ResourceDownloadError r =
new ResourceDownloadError(resourceLocation, msg);
r.initCause(e);
throw r;
} finally {
// clean up all I/O resources
closeQuietly(fout);
closeQuietly(gzipis);
}
return copy;
}
}