001/*
002 * (C) Copyright 2018 Nuxeo (http://nuxeo.com/) and others.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *     http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 *
016 * Contributors:
017 *     Gethin James
018 */
019package org.nuxeo.elasticsearch.aggregate;
020
021import java.util.Collections;
022
023import org.elasticsearch.index.query.QueryBuilder;
024import org.elasticsearch.index.query.QueryBuilders;
025import org.elasticsearch.search.aggregations.bucket.SingleBucketAggregation;
026import org.nuxeo.ecm.core.api.DocumentModel;
027import org.nuxeo.ecm.platform.query.api.AggregateDefinition;
028import org.nuxeo.ecm.platform.query.core.BucketTerm;
029
030import com.fasterxml.jackson.annotation.JsonIgnore;
031
032/**
033 * An aggregate that returns a single bucket.
034 *
035 * @since 10.3
036 */
037public abstract class SingleBucketAggregate extends AggregateEsBase<SingleBucketAggregation, BucketTerm> {
038
039    protected long docCount;
040
041    public SingleBucketAggregate(AggregateDefinition definition, DocumentModel searchDocument) {
042        super(definition, searchDocument);
043    }
044
045    @Override
046    public void parseAggregation(SingleBucketAggregation aggregation) {
047        this.docCount = aggregation.getDocCount();
048        this.buckets = Collections.singletonList(new BucketTerm(definition.getType(), docCount));
049    }
050
051    @JsonIgnore
052    @Override
053    public QueryBuilder getEsFilter() {
054        if (getSelection().isEmpty()) {
055            return null;
056        }
057        return QueryBuilders.termsQuery(getField(), getSelection());
058    }
059
060    public long getDocCount() {
061        return docCount;
062    }
063}