/*
* Licensed to Elasticsearch under one or more contributor
* license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright
* ownership. Elasticsearch 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.elasticsearch.search.aggregations.bucket.significant;
import org.elasticsearch.common.inject.Inject;
import org.elasticsearch.common.xcontent.XContentParser;
import org.elasticsearch.search.aggregations.Aggregator;
import org.elasticsearch.search.aggregations.AggregatorFactory;
import org.elasticsearch.search.aggregations.bucket.BucketUtils;
import org.elasticsearch.search.aggregations.bucket.significant.heuristics.JLHScore;
import org.elasticsearch.search.aggregations.bucket.significant.heuristics.SignificanceHeuristic;
import org.elasticsearch.search.aggregations.bucket.significant.heuristics.SignificanceHeuristicParserMapper;
import org.elasticsearch.search.aggregations.bucket.terms.TermsAggregator;
import org.elasticsearch.search.aggregations.bucket.terms.support.IncludeExclude;
import org.elasticsearch.search.aggregations.support.ValuesSourceParser;
import org.elasticsearch.search.internal.SearchContext;
import java.io.IOException;
/**
*
*/
public class SignificantTermsParser implements Aggregator.Parser {
private final SignificanceHeuristicParserMapper significanceHeuristicParserMapper;
@Inject
public SignificantTermsParser(SignificanceHeuristicParserMapper significanceHeuristicParserMapper) {
this.significanceHeuristicParserMapper = significanceHeuristicParserMapper;
}
@Override
public String type() {
return SignificantStringTerms.TYPE.name();
}
@Override
public AggregatorFactory parse(String aggregationName, XContentParser parser, SearchContext context) throws IOException {
SignificantTermsParametersParser aggParser = new SignificantTermsParametersParser(significanceHeuristicParserMapper);
ValuesSourceParser vsParser = ValuesSourceParser.any(aggregationName, SignificantStringTerms.TYPE, context)
.scriptable(false)
.formattable(true)
.build();
IncludeExclude.Parser incExcParser = new IncludeExclude.Parser(aggregationName, SignificantStringTerms.TYPE, context);
aggParser.parse(aggregationName, parser, context, vsParser, incExcParser);
TermsAggregator.BucketCountThresholds bucketCountThresholds = aggParser.getBucketCountThresholds();
if (bucketCountThresholds.getShardSize() == aggParser.getDefaultBucketCountThresholds().getShardSize()) {
//The user has not made a shardSize selection .
//Use default heuristic to avoid any wrong-ranking caused by distributed counting
//but request double the usual amount.
//We typically need more than the number of "top" terms requested by other aggregations
//as the significance algorithm is in less of a position to down-select at shard-level -
//some of the things we want to find have only one occurrence on each shard and as
// such are impossible to differentiate from non-significant terms at that early stage.
bucketCountThresholds.setShardSize(2 * BucketUtils.suggestShardSideQueueSize(bucketCountThresholds.getRequiredSize(), context.numberOfShards()));
}
bucketCountThresholds.ensureValidity();
SignificanceHeuristic significanceHeuristic = aggParser.getSignificanceHeuristic();
if (significanceHeuristic == null) {
significanceHeuristic = JLHScore.INSTANCE;
}
return new SignificantTermsAggregatorFactory(aggregationName, vsParser.config(), bucketCountThresholds, aggParser.getIncludeExclude(), aggParser.getExecutionHint(), aggParser.getFilter(), significanceHeuristic);
}
}