backup.store.local.LocalBackupStore.java Source code

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Here is the source code for backup.store.local.LocalBackupStore.java

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/*
 * Copyright 2016 Fortitude Technologies LLC
 * 
 * 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 backup.store.local;

import java.io.File;
import java.io.FileFilter;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.Arrays;
import java.util.Iterator;
import java.util.List;
import java.util.concurrent.TimeUnit;

import org.apache.commons.configuration.Configuration;
import org.apache.commons.io.FileUtils;
import org.apache.commons.io.IOUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.google.common.base.Splitter;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableList.Builder;
import com.google.common.collect.Iterators;

import backup.store.BackupStore;
import backup.store.ExtendedBlock;
import backup.store.ExtendedBlockEnum;
import backup.store.LengthInputStream;

public class LocalBackupStore extends BackupStore {

    private final static Logger LOG = LoggerFactory.getLogger(LocalBackupStore.class);

    private static final String META = ".meta";
    private static final String DATA = ".data";

    private File dir;

    @Override
    public void init() throws Exception {
        Configuration configuration = getConf();
        String localPath = configuration.getString(LocalBackupStoreConstants.DFS_BACKUP_LOCALBACKUPSTORE_PATH);
        dir = new File(localPath);
        dir.mkdirs();
    }

    @Override
    public void backupBlock(ExtendedBlock extendedBlock, LengthInputStream data, LengthInputStream metaData)
            throws Exception {
        LOG.info("before sleep backupBlock {} dataLength {} metaDataLength", extendedBlock, data.getLength(),
                metaData.getLength());
        Thread.sleep(TimeUnit.SECONDS.toMillis(1));
        LOG.info("after sleep backupBlock {} dataLength {} metaDataLength", extendedBlock, data.getLength(),
                metaData.getLength());
        File dataFile = getDataFile(extendedBlock);
        File metaDataFile = getMetaDataFile(extendedBlock);
        try (FileOutputStream output = new FileOutputStream(dataFile)) {
            IOUtils.copy(data, output);
        }
        if (dataFile.length() != extendedBlock.getLength()) {
            throw new IOException("length of backup file " + dataFile.length() + " different than block "
                    + extendedBlock.getLength());
        }
        try (FileOutputStream output = new FileOutputStream(metaDataFile)) {
            IOUtils.copy(metaData, output);
        }
    }

    @Override
    public boolean hasBlock(ExtendedBlock extendedBlock) throws Exception {
        File metaDataFile = getMetaDataFile(extendedBlock);
        if (metaDataFile.exists()) {
            File dataFile = getDataFile(extendedBlock);
            if (dataFile.exists()) {
                return dataFile.length() == extendedBlock.getLength();
            }
        }
        return false;
    }

    @Override
    public InputStream getMetaDataInputStream(ExtendedBlock extendedBlock) throws Exception {
        File metaDataFile = getMetaDataFile(extendedBlock);
        return new FileInputStream(metaDataFile);
    }

    @Override
    public InputStream getDataInputStream(ExtendedBlock extendedBlock) throws Exception {
        File dataFile = getDataFile(extendedBlock);
        return new FileInputStream(dataFile);
    }

    @Override
    public ExtendedBlockEnum<Void> getExtendedBlocks() {
        File[] pools = dir.listFiles((FileFilter) pathname -> pathname.isDirectory());
        Builder<Iterator<ExtendedBlock>> builder = ImmutableList.builder();
        for (File pool : pools) {
            builder.add(getExtendedBlocks(pool));
        }
        return ExtendedBlockEnum.toExtendedBlockEnum(Iterators.concat(builder.build().iterator()));
    }

    @Override
    public void deleteBlock(ExtendedBlock extendedBlock) {
        getDataFile(extendedBlock).delete();
        getMetaDataFile(extendedBlock).delete();
    }

    private Iterator<ExtendedBlock> getExtendedBlocks(File pool) {
        List<File> list = Arrays.asList(pool.listFiles((FileFilter) pathname -> pathname.getName().endsWith(DATA)));
        Iterator<File> iterator = list.iterator();
        return new Iterator<ExtendedBlock>() {
            @Override
            public boolean hasNext() {
                return iterator.hasNext();
            }

            @Override
            public ExtendedBlock next() {
                return toExtendedBlock(iterator.next());
            }
        };
    }

    private ExtendedBlock toExtendedBlock(File block) {
        String blockPoolId = block.getParentFile().getName();
        String name = block.getName();
        name = name.substring(0, name.indexOf('.'));
        ImmutableList<String> list = ImmutableList.copyOf(Splitter.on('_').split(name));
        long blockId = Long.parseLong(list.get(0));
        long genstamp = Long.parseLong(list.get(1));
        return new ExtendedBlock(blockPoolId, blockId, block.length(), genstamp);
    }

    private File getMetaDataFile(ExtendedBlock extendedBlock) {
        return new File(getPool(extendedBlock), getBlockName(extendedBlock) + META);
    }

    private File getDataFile(ExtendedBlock extendedBlock) {
        return new File(getPool(extendedBlock), getBlockName(extendedBlock) + DATA);
    }

    private File getPool(ExtendedBlock extendedBlock) {
        File pool = new File(dir, extendedBlock.getPoolId());
        pool.mkdirs();
        return pool;
    }

    private String getBlockName(ExtendedBlock extendedBlock) {
        return Long.toString(extendedBlock.getBlockId()) + "_" + Long.toString(extendedBlock.getGenerationStamp());
    }

    @Override
    public void destroyAllBlocks() throws Exception {
        FileUtils.deleteDirectory(dir);
    }

}