/**
* Copyright (c) 2011-2013 Optimax Software Ltd.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* * Neither the name of Optimax Software, ElasticInbox, nor the names
* of its contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package com.elasticinbox.core.blob.store;
import static com.elasticinbox.core.blob.store.BlobStoreConstants.*;
import java.io.IOException;
import java.io.InputStream;
import java.net.URI;
import java.security.GeneralSecurityException;
import java.util.UUID;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.elasticinbox.common.utils.Assert;
import com.elasticinbox.config.Configurator;
import com.elasticinbox.config.DatabaseConstants;
import com.elasticinbox.core.blob.BlobDataSource;
import com.elasticinbox.core.blob.BlobURI;
import com.elasticinbox.core.blob.compression.CompressionHandler;
import com.elasticinbox.core.blob.compression.DeflateCompressionHandler;
import com.elasticinbox.core.blob.encryption.EncryptionHandler;
import com.elasticinbox.core.model.Mailbox;
import com.google.common.io.ByteStreams;
import com.google.common.io.FileBackedOutputStream;
/**
* Blob storage mediator is an abstraction layer containing logic which
* determines where to store or how to access given blob.
*
* @author Rustam Aliyev
*/
public final class BlobStorageMediator implements BlobStorage
{
private static final Logger logger =
LoggerFactory.getLogger(BlobStorageMediator.class);
protected final CompressionHandler compressionHandler;
private BlobStorage cloudBlobStorage;
private BlobStorage dbBlobStorage;
/**
* Initialise mediator with compression and encryption handlers for writes.
* To disable compression/encryption set value to null.
*
* @param ch
* Injected compression handler
* @param eh
* Injected encryption handler
*/
public BlobStorageMediator(final CompressionHandler ch, final EncryptionHandler eh)
{
this.compressionHandler = ch;
cloudBlobStorage = new CloudBlobStorage(eh);
dbBlobStorage = new CassandraBlobStorage();
}
public BlobURI write(final UUID messageId, final Mailbox mailbox, final String profileName,
final InputStream in, final Long size) throws IOException,
GeneralSecurityException
{
Assert.notNull(in, "No data to store");
BlobURI blobUri;
InputStream in1;
Long updatedSize = size;
boolean compressed = false;
// compress stream and calculate compressed size
if ((compressionHandler != null) && (size > MIN_COMPRESS_SIZE))
{
InputStream compressedInputStream = compressionHandler.compress(in);
FileBackedOutputStream fbout = new FileBackedOutputStream(MAX_MEMORY_FILE_SIZE, true);
updatedSize = ByteStreams.copy(compressedInputStream, fbout);
in1 = fbout.getSupplier().getInput();
compressed = true;
} else {
in1 = in;
}
if (updatedSize <= Configurator.getDatabaseBlobMaxSize())
{
logger.debug(
"Storing Blob in the database because size ({}KB) was less than database threshold {}KB",
updatedSize, Configurator.getDatabaseBlobMaxSize());
blobUri = dbBlobStorage.write(messageId, mailbox, null, in1, updatedSize);
} else {
logger.debug(
"Storing Blob in the cloud because size ({}KB) was greater than database threshold {}KB",
updatedSize, Configurator.getDatabaseBlobMaxSize());
blobUri = cloudBlobStorage.write(messageId, mailbox, Configurator.getBlobStoreWriteProfileName(), in1, updatedSize);
}
// add compression information to the blob URI
if (compressed) {
blobUri.setCompression(compressionHandler.getType());
}
return blobUri;
}
public BlobDataSource read(final URI uri) throws IOException
{
// check if blob was stored for the message
Assert.notNull(uri, "URI cannot be null");
BlobDataSource blobDS;
BlobURI blobUri = new BlobURI().fromURI(uri);
if (blobUri.getProfile().equals(DatabaseConstants.DATABASE_PROFILE)) {
blobDS = dbBlobStorage.read(uri);
} else {
blobDS = cloudBlobStorage.read(uri);
}
// if compressed, add compression handler to data source
if ((blobUri.getCompression() != null && blobUri.getCompression()
.equals(DeflateCompressionHandler.COMPRESSION_TYPE_DEFLATE)) ||
// TODO: deprecated suffix based compression detection
// kept for backward compatibility with 0.3
blobUri.getName().endsWith(BlobStoreConstants.COMPRESS_SUFFIX))
{
CompressionHandler ch = new DeflateCompressionHandler();
return new BlobDataSource(uri, blobDS.getInputStream(), ch);
} else {
return blobDS;
}
}
public void delete(final URI uri) throws IOException
{
// check if blob was stored for the message, silently skip otherwise
if (uri == null) {
return;
}
boolean isDbProfile = new BlobURI().fromURI(uri).getProfile()
.equals(DatabaseConstants.DATABASE_PROFILE);
if (isDbProfile) {
dbBlobStorage.delete(uri);
} else {
cloudBlobStorage.delete(uri);
}
}
}