/**
* 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.waveprotocol.box.server.persistence.migration;
import com.google.common.collect.ImmutableSet;
import org.waveprotocol.box.common.ExceptionalIterator;
import org.waveprotocol.box.server.persistence.PersistenceException;
import org.waveprotocol.box.server.waveserver.DeltaStore;
import org.waveprotocol.box.server.waveserver.DeltaStore.DeltasAccess;
import org.waveprotocol.box.server.waveserver.WaveletDeltaRecord;
import org.waveprotocol.wave.model.id.WaveId;
import org.waveprotocol.wave.model.id.WaveletId;
import org.waveprotocol.wave.model.id.WaveletName;
import org.waveprotocol.wave.model.version.HashedVersion;
import org.waveprotocol.wave.util.logging.Log;
import java.io.IOException;
import java.util.ArrayList;
/**
*
* An utility class to copy all deltas between storages. Already existing Waves
* in the target store wont be changed.
*
* It is NOT an incremental process.
*
* @author pablojan@gmail.com (Pablo Ojanguren)
*
*/
public class DeltaMigrator {
private static final Log LOG = Log.get(DeltaMigrator.class);
protected DeltaStore sourceStore = null;
protected DeltaStore targetStore = null;
public DeltaMigrator(DeltaStore sourceStore, DeltaStore targetStore) {
this.sourceStore = sourceStore;
this.targetStore = targetStore;
}
public void run() {
LOG.info("Starting Wave migration from " + sourceStore.getClass().getSimpleName() + " to "
+ targetStore.getClass().getSimpleName());
long startTime = System.currentTimeMillis();
try {
ExceptionalIterator<WaveId, PersistenceException> srcItr = sourceStore.getWaveIdIterator();
// Waves
while (srcItr.hasNext()) {
WaveId waveId = srcItr.next();
ImmutableSet<WaveletId> waveletIds = sourceStore.lookup(waveId);
if (!targetStore.lookup(waveId).isEmpty()) {
LOG.info("Skipping Wave because it's found in target store : " + waveId.toString());
continue;
}
LOG.info("Migrating Wave : " + waveId.toString() + " with " + waveletIds.size()
+ " wavelets");
int waveletsTotal = waveletIds.size();
int waveletsCount = 0;
// Wavelets
for (WaveletId waveletId : waveletIds) {
waveletsCount++;
LOG.info("Migrating wavelet " + waveletsCount + "/" + waveletsTotal + " : "
+ waveletId.toString());
DeltasAccess sourceDeltas = sourceStore.open(WaveletName.of(waveId, waveletId));
DeltasAccess targetDeltas = targetStore.open(WaveletName.of(waveId, waveletId));
// Get all deltas from last version to initial version (0): reverse
// order
int deltasCount = 0;
ArrayList<WaveletDeltaRecord> deltas = new ArrayList<WaveletDeltaRecord>();
HashedVersion deltaResultingVersion = sourceDeltas.getEndVersion();
// Deltas
while (deltaResultingVersion != null && deltaResultingVersion.getVersion() != 0) {
deltasCount++;
WaveletDeltaRecord deltaRecord =
sourceDeltas.getDeltaByEndVersion(deltaResultingVersion.getVersion());
deltas.add(deltaRecord);
// get the previous delta, this is the appliedAt
deltaResultingVersion = deltaRecord.getAppliedAtVersion();
}
LOG.info("Appending " + deltasCount + "deltas to target");
targetDeltas.append(deltas);
}
} // While Waves
long endTime = System.currentTimeMillis();
LOG.info("Migration completed. Total time = " + (endTime - startTime) + "ms");
} catch (PersistenceException e) {
throw new RuntimeException(e);
} catch (IOException e) {
throw new RuntimeException(e);
}
}
}