/*
* 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.nifi.provenance.index.lucene;
import java.util.List;
import java.util.Optional;
import org.apache.nifi.provenance.ProvenanceEventRecord;
import org.apache.nifi.provenance.search.Query;
import org.apache.nifi.provenance.serialization.StorageSummary;
import org.apache.nifi.util.RingBuffer;
public class LatestEventsQuery implements CachedQuery {
final RingBuffer<Long> latestRecords = new RingBuffer<>(1000);
@Override
public void update(final ProvenanceEventRecord event, final StorageSummary storageSummary) {
latestRecords.add(storageSummary.getEventId());
}
@Override
public Optional<List<Long>> evaluate(final Query query) {
if (latestRecords.getSize() < query.getMaxResults()) {
return Optional.empty();
}
if (query.getSearchTerms().isEmpty() && query.getStartDate() == null && query.getEndDate() == null) {
final List<Long> eventList = latestRecords.asList();
if (eventList.size() > query.getMaxResults()) {
return Optional.of(eventList.subList(0, query.getMaxResults()));
} else {
return Optional.of(eventList);
}
} else {
return Optional.empty();
}
}
}