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* 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.document.mongo;
import java.util.List;
import java.util.Set;
import javax.annotation.Nullable;
import com.google.common.base.Function;
import com.google.common.base.Joiner;
import com.google.common.base.StandardSystemProperty;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.Iterables;
import com.mongodb.BasicDBObject;
import com.mongodb.DBCollection;
import com.mongodb.DBCursor;
import com.mongodb.DBObject;
import com.mongodb.QueryBuilder;
import com.mongodb.ReadPreference;
import com.mongodb.WriteConcern;
import com.mongodb.WriteResult;
import org.apache.jackrabbit.oak.plugins.document.Collection;
import org.apache.jackrabbit.oak.plugins.document.Document;
import org.apache.jackrabbit.oak.plugins.document.NodeDocument;
import org.apache.jackrabbit.oak.plugins.document.VersionGCSupport;
import org.apache.jackrabbit.oak.plugins.document.util.CloseableIterable;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import static com.google.common.collect.Iterables.transform;
import static com.mongodb.QueryBuilder.start;
import static org.apache.jackrabbit.oak.plugins.document.NodeDocument.SplitDocType;
/**
* Mongo specific version of VersionGCSupport which uses mongo queries
* to fetch required NodeDocuments
*
* <p>Version collection involves looking into old record and mostly unmodified
* documents. In such case read from secondaries are preferred</p>
*/
public class MongoVersionGCSupport extends VersionGCSupport {
private final Logger log = LoggerFactory.getLogger(getClass());
private final MongoDocumentStore store;
public MongoVersionGCSupport(MongoDocumentStore store) {
super(store);
this.store = store;
}
@Override
public CloseableIterable<NodeDocument> getPossiblyDeletedDocs(final long lastModifiedTime) {
//_deletedOnce == true && _modified < lastModifiedTime
DBObject query =
start(NodeDocument.DELETED_ONCE).is(Boolean.TRUE)
.put(NodeDocument.MODIFIED_IN_SECS).lessThan(NodeDocument.getModifiedInSecs(lastModifiedTime))
.get();
DBCursor cursor = getNodeCollection().find(query).setReadPreference(ReadPreference.secondaryPreferred());
return CloseableIterable.wrap(transform(cursor, new Function<DBObject, NodeDocument>() {
@Override
public NodeDocument apply(DBObject input) {
return store.convertFromDBObject(Collection.NODES, input);
}
}), cursor);
}
@Override
public int deleteSplitDocuments(Set<SplitDocType> gcTypes, long oldestRevTimeStamp) {
//OR condition has to be first as we have a index for that
//((type == DEFAULT_NO_CHILD || type == PROP_COMMIT_ONLY ..) && _sdMaxRevTime < oldestRevTimeStamp(in secs)
QueryBuilder orClause = start();
for(SplitDocType type : gcTypes){
orClause.or(start(NodeDocument.SD_TYPE).is(type.typeCode()).get());
}
DBObject query = start()
.and(
orClause.get(),
start(NodeDocument.SD_MAX_REV_TIME_IN_SECS)
.lessThan(NodeDocument.getModifiedInSecs(oldestRevTimeStamp))
.get()
).get();
if(log.isDebugEnabled()){
//if debug level logging is on then determine the id of documents to be deleted
//and log them
logSplitDocIdsTobeDeleted(query);
}
WriteResult writeResult = getNodeCollection().remove(query, WriteConcern.SAFE);
if (writeResult.getError() != null) {
//TODO This might be temporary error or we fail fast and let next cycle try again
log.warn("Error occurred while deleting old split documents from Mongo {}", writeResult.getError());
}
return writeResult.getN();
}
private void logSplitDocIdsTobeDeleted(DBObject query) {
// Fetch only the id
final BasicDBObject keys = new BasicDBObject(Document.ID, 1);
List<String> ids;
DBCursor cursor = getNodeCollection().find(query, keys)
.setReadPreference(ReadPreference.secondaryPreferred());
try {
ids = ImmutableList.copyOf(Iterables.transform(cursor, new Function<DBObject, String>() {
@Override
public String apply(@Nullable DBObject input) {
return (String) input.get(Document.ID);
}
}));
} finally {
cursor.close();
}
StringBuilder sb = new StringBuilder("Split documents with following ids were deleted as part of GC \n");
Joiner.on(StandardSystemProperty.LINE_SEPARATOR.value()).appendTo(sb, ids);
log.debug(sb.toString());
}
private DBCollection getNodeCollection(){
return store.getDBCollection(Collection.NODES);
}
}