/**
* 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.mongodb;
import java.io.IOException;
import java.util.Collection;
import org.waveprotocol.box.common.Receiver;
import org.waveprotocol.box.server.persistence.PersistenceException;
import org.waveprotocol.box.server.waveserver.ByteStringMessage;
import org.waveprotocol.box.server.waveserver.DeltaStore;
import org.waveprotocol.box.server.waveserver.WaveletDeltaRecord;
import org.waveprotocol.wave.federation.Proto.ProtocolAppliedWaveletDelta;
import org.waveprotocol.wave.model.id.WaveletName;
import org.waveprotocol.wave.model.operation.wave.TransformedWaveletDelta;
import org.waveprotocol.wave.model.util.Preconditions;
import org.waveprotocol.wave.model.version.HashedVersion;
import org.waveprotocol.wave.model.wave.data.WaveletData;
import org.waveprotocol.wave.util.logging.Log;
import com.mongodb.BasicDBObject;
import com.mongodb.DBCollection;
import com.mongodb.DBCursor;
import com.mongodb.DBObject;
import com.mongodb.WriteConcern;
/**
* A MongoDB based Delta Access implementation using a simple <b>deltas</b>
* collection, storing a delta record per each MongoDb document.
*
* @author pablojan@gmail.com (Pablo Ojanguren)
*
*/
public class MongoDbDeltaCollection implements DeltaStore.DeltasAccess {
private static final Log LOG = Log.get(MongoDbDeltaCollection.class);
/** Wavelet name to work with. */
private final WaveletName waveletName;
/** MongoDB Collection object for delta storage */
private final DBCollection deltasCollection;
/** MongoDB based wavelet snapshot store */
private final MongoDBSnapshotStore snapshotStore;
public static MongoDbDeltaCollection create(WaveletName waveletName, DBCollection deltasCollection, MongoDBSnapshotStore snapshotStore) {
return new MongoDbDeltaCollection(waveletName, deltasCollection, snapshotStore);
}
/**
* Construct a new Delta Access object for the wavelet
*
* @param waveletName The wavelet name.
* @param deltaDbCollection The MongoDB deltas collection
*/
public MongoDbDeltaCollection(WaveletName waveletName, DBCollection deltasCollection, MongoDBSnapshotStore snapshotStore) {
this.waveletName = waveletName;
this.deltasCollection = deltasCollection;
this.snapshotStore = snapshotStore;
}
@Override
public WaveletName getWaveletName() {
return waveletName;
}
/**
* Create a new DBObject for a common query to select this wavelet
*
* @return DBObject query
*/
protected DBObject createWaveletDBQuery() {
DBObject query = new BasicDBObject();
query.put(MongoDbDeltaStoreUtil.FIELD_WAVE_ID, waveletName.waveId.serialise());
query.put(MongoDbDeltaStoreUtil.FIELD_WAVELET_ID, waveletName.waveletId.serialise());
return query;
}
@Override
public boolean isEmpty() {
return deltasCollection.count(createWaveletDBQuery()) == 0;
}
@Override
public HashedVersion getEndVersion() {
// Search the max of delta.getTransformedDelta().getResultingVersion()
DBObject query = createWaveletDBQuery();
DBObject sort = new BasicDBObject();
sort.put(MongoDbDeltaStoreUtil.FIELD_TRANSFORMED_RESULTINGVERSION_VERSION, -1); // Descending
DBObject field = new BasicDBObject();
field.put(MongoDbDeltaStoreUtil.FIELD_TRANSFORMED_RESULTINGVERSION, 1);
DBObject result = deltasCollection.findOne(query, field, sort);
return result != null ? MongoDbDeltaStoreUtil
.deserializeHashedVersion((DBObject) ((DBObject) result
.get(MongoDbDeltaStoreUtil.FIELD_TRANSFORMED))
.get(MongoDbDeltaStoreUtil.FIELD_RESULTINGVERSION)) : null;
}
@Override
public WaveletDeltaRecord getDelta(long version) throws IOException {
DBObject query = createWaveletDBQuery();
query.put(MongoDbDeltaStoreUtil.FIELD_TRANSFORMED_APPLIEDATVERSION, version);
DBObject result = deltasCollection.findOne(query);
WaveletDeltaRecord waveletDelta = null;
if (result != null) try {
waveletDelta = MongoDbDeltaStoreUtil.deserializeWaveletDeltaRecord(result);
} catch (PersistenceException e) {
throw new IOException(e);
}
return waveletDelta;
}
@Override
public WaveletDeltaRecord getDeltaByEndVersion(long version) throws IOException {
DBObject query = createWaveletDBQuery();
query.put(MongoDbDeltaStoreUtil.FIELD_TRANSFORMED_RESULTINGVERSION_VERSION, version);
DBObject result = deltasCollection.findOne(query);
WaveletDeltaRecord waveletDelta = null;
if (result != null)
try {
MongoDbDeltaStoreUtil.deserializeWaveletDeltaRecord(result);
} catch (PersistenceException e) {
throw new IOException(e);
}
return waveletDelta;
}
@Override
public HashedVersion getAppliedAtVersion(long version) throws IOException {
DBObject query = createWaveletDBQuery();
query.put(MongoDbDeltaStoreUtil.FIELD_TRANSFORMED_APPLIEDATVERSION, version);
DBObject result = deltasCollection.findOne(query);
if (result != null)
return MongoDbDeltaStoreUtil.deserializeHashedVersion((DBObject) result
.get(MongoDbDeltaStoreUtil.FIELD_APPLIEDATVERSION));
return null;
}
@Override
public HashedVersion getResultingVersion(long version) throws IOException {
DBObject query = createWaveletDBQuery();
query.put(MongoDbDeltaStoreUtil.FIELD_TRANSFORMED_APPLIEDATVERSION, version);
DBObject result = deltasCollection.findOne(query);
if (result != null)
return MongoDbDeltaStoreUtil.deserializeHashedVersion((DBObject) result
.get(MongoDbDeltaStoreUtil.FIELD_TRANSFORMED_RESULTINGVERSION));
return null;
}
@Override
public ByteStringMessage<ProtocolAppliedWaveletDelta> getAppliedDelta(long version)
throws IOException {
WaveletDeltaRecord delta = getDelta(version);
return (delta != null) ? delta.getAppliedDelta() : null;
}
@Override
public TransformedWaveletDelta getTransformedDelta(long version) throws IOException {
WaveletDeltaRecord delta = getDelta(version);
return (delta != null) ? delta.getTransformedDelta() : null;
}
@Override
public void close() throws IOException {
// Does nothing.
}
@Override
public void append(Collection<WaveletDeltaRecord> newDeltas) throws PersistenceException {
for (WaveletDeltaRecord delta : newDeltas) {
// Using Journaled Write Concern
// (http://docs.mongodb.org/manual/core/write-concern/#journaled)
deltasCollection.insert(MongoDbDeltaStoreUtil.serialize(delta,
waveletName.waveId.serialise(), waveletName.waveletId.serialise()),
WriteConcern.JOURNALED);
}
}
@Override
public long getAllDeltas(Receiver<WaveletDeltaRecord> receiver) throws IOException {
DBObject query = createWaveletDBQuery();
BasicDBObject sort = new BasicDBObject();
sort.put(MongoDbDeltaStoreUtil.FIELD_TRANSFORMED_APPLIEDATVERSION, 1);
sort.put(MongoDbDeltaStoreUtil.FIELD_TRANSFORMED + "."
+ MongoDbDeltaStoreUtil.FIELD_APPLICATIONTIMESTAMP, 1);
DBCursor result = deltasCollection.find(query).sort(sort);
long count = 0;
HashedVersion lastResultingVersion = null;
while (result.hasNext()) {
DBObject obj = result.next();
WaveletDeltaRecord delta;
try {
delta = MongoDbDeltaStoreUtil.deserializeWaveletDeltaRecord(obj);
} catch (PersistenceException e) {
throw new IOException(e);
}
if (lastResultingVersion != null && !delta.getAppliedAtVersion().equals(lastResultingVersion)) {
LOG.warning("Skipping delta at v=" + delta.getAppliedAtVersion().getVersion() + " to v="
+ delta.getTransformedDelta().getAppliedAtVersion());
continue;
}
if (!receiver.put(delta)) {
throw new IllegalStateException("Error loading delta from persistence at v="
+ delta.getAppliedAtVersion().getVersion() + " to v="
+ delta.getTransformedDelta().getAppliedAtVersion());
}
lastResultingVersion = delta.getTransformedDelta().getResultingVersion();
count++;
}
return count;
}
@Override
public long getDeltasInRange(long startVersion, long endVersion,
Receiver<WaveletDeltaRecord> receiver) throws IOException {
BasicDBObject sort = new BasicDBObject();
sort.put(MongoDbDeltaStoreUtil.FIELD_TRANSFORMED_RESULTINGVERSION_VERSION, 1);
DBObject query = createWaveletDBQuery();
query.put(MongoDbDeltaStoreUtil.FIELD_TRANSFORMED_RESULTINGVERSION_VERSION,
new BasicDBObject("$gt", startVersion).append("$lte", endVersion));
DBCursor result = deltasCollection.find(query).sort(sort);
long count = 0;
HashedVersion lastResultingVersion = null;
while (result.hasNext()) {
DBObject obj = result.next();
WaveletDeltaRecord delta;
try {
delta = MongoDbDeltaStoreUtil.deserializeWaveletDeltaRecord(obj);
} catch (PersistenceException e) {
throw new IOException(e);
}
if (lastResultingVersion != null && !delta.getAppliedAtVersion().equals(lastResultingVersion)) {
LOG.warning("Skipping delta at v=" + delta.getAppliedAtVersion().getVersion() + " to v="
+ delta.getTransformedDelta().getAppliedAtVersion());
continue;
}
if (!receiver.put(delta)) {
throw new IllegalStateException("Error loading delta from persistence at v="
+ delta.getAppliedAtVersion().getVersion() + " to v="
+ delta.getTransformedDelta().getAppliedAtVersion());
}
lastResultingVersion = delta.getTransformedDelta().getResultingVersion();
count++;
}
return count;
}
@Override
public WaveletDeltaRecord getLastDelta() throws IOException {
// Search the max of delta.getTransformedDelta().getResultingVersion()
DBObject query = createWaveletDBQuery();
DBObject sort = new BasicDBObject();
sort.put(MongoDbDeltaStoreUtil.FIELD_TRANSFORMED_RESULTINGVERSION_VERSION, -1); // Descending
DBObject result = deltasCollection.findOne(query, null, sort);
try {
return result != null ? MongoDbDeltaStoreUtil
.deserializeWaveletDeltaRecord(result) : null;
} catch (PersistenceException e) {
throw new IOException(e);
}
}
@Override
public DeltaStore.Snapshot loadSnapshot() throws PersistenceException {
return snapshotStore.load(waveletName);
}
@Override
public void storeSnapshot(WaveletData waveletData)
throws PersistenceException {
Preconditions.checkArgument(waveletName.equals(WaveletName.of(waveletData.getWaveId(), waveletData.getWaveletId())),
"Can't store snapshots for different wavelet");
snapshotStore.store(waveletData);
}
}