/*
* 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.apache.jackrabbit.oak.plugins.segment.mongo;
import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.collect.ImmutableMap.of;
import static com.mongodb.ReadPreference.nearest;
import static com.mongodb.ReadPreference.primary;
import static org.apache.jackrabbit.oak.plugins.memory.EmptyNodeState.EMPTY_NODE;
import java.nio.ByteBuffer;
import java.util.Map;
import java.util.UUID;
import javax.annotation.Nonnull;
import org.apache.jackrabbit.oak.plugins.segment.AbstractStore;
import org.apache.jackrabbit.oak.plugins.segment.Journal;
import org.apache.jackrabbit.oak.plugins.segment.Segment;
import org.apache.jackrabbit.oak.spi.state.NodeBuilder;
import com.google.common.collect.Maps;
import com.mongodb.BasicDBObject;
import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.DBObject;
import com.mongodb.WriteConcern;
public class MongoStore extends AbstractStore {
private final WriteConcern concern = WriteConcern.SAFE; // TODO: MAJORITY?
private final DB db;
private final DBCollection segments;
private final Map<String, Journal> journals = Maps.newHashMap();
public MongoStore(DB db, int cacheSizeMB) {
super(cacheSizeMB);
this.db = checkNotNull(db);
this.segments = db.getCollection("segments");
NodeBuilder builder = EMPTY_NODE.builder();
builder.child("root");
journals.put("root", new MongoJournal(
this, db.getCollection("journals"),
concern, builder.getNodeState()));
}
@Override
public void close() {
}
@Override
public synchronized Journal getJournal(String name) {
Journal journal = journals.get(name);
if (journal == null) {
journal = new MongoJournal(
this, db.getCollection("journals"), concern, name);
journals.put(name, journal);
}
return journal;
}
@Override
public void writeSegment(
UUID segmentId, byte[] data, int offset, int length) {
if (offset != 0 || length != data.length) {
byte[] b = new byte[length];
System.arraycopy(data, offset, b, 0, length);
data = b;
}
BasicDBObject segment = new BasicDBObject();
segment.put("_id", segmentId.toString());
segment.put("data", data);
segments.insert(segment, concern);
}
@Override @Nonnull
protected Segment loadSegment(UUID segmentId) {
DBObject id = new BasicDBObject("_id", segmentId.toString());
DBObject fields = new BasicDBObject(of("data", 1));
DBObject segment = segments.findOne(id, fields, nearest());
if (segment == null) {
segment = segments.findOne(id, fields, primary());
if (segment == null) {
throw new IllegalStateException(
"Segment " + segmentId + " not found");
}
}
byte[] data = (byte[]) segment.get("data");
return createSegment(segmentId, ByteBuffer.wrap(data));
}
@Override
public void deleteSegment(UUID segmentId) {
segments.remove(new BasicDBObject("_id", segmentId.toString()));
super.deleteSegment(segmentId);;
}
}