/*
* 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;
import com.google.common.collect.ImmutableMap;
import org.apache.lucene.index.LeafReaderContext;
import org.apache.lucene.search.ConstantScoreQuery;
import org.apache.lucene.search.Filter;
import org.apache.lucene.search.FilteredQuery;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.Scorer;
import org.apache.lucene.search.SimpleCollector;
import org.elasticsearch.ElasticsearchException;
import org.elasticsearch.common.inject.Inject;
import org.elasticsearch.common.lucene.search.Queries;
import org.elasticsearch.common.lucene.search.XCollector;
import org.elasticsearch.search.SearchParseElement;
import org.elasticsearch.search.SearchPhase;
import org.elasticsearch.search.aggregations.bucket.global.GlobalAggregator;
import org.elasticsearch.search.aggregations.support.AggregationContext;
import org.elasticsearch.search.internal.SearchContext;
import org.elasticsearch.search.query.QueryPhaseExecutionException;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.Map;
/**
*
*/
public class AggregationPhase implements SearchPhase {
private final AggregationParseElement parseElement;
private final AggregationBinaryParseElement binaryParseElement;
@Inject
public AggregationPhase(AggregationParseElement parseElement, AggregationBinaryParseElement binaryParseElement) {
this.parseElement = parseElement;
this.binaryParseElement = binaryParseElement;
}
@Override
public Map<String, ? extends SearchParseElement> parseElements() {
return ImmutableMap.<String, SearchParseElement>builder()
.put("aggregations", parseElement)
.put("aggs", parseElement)
.put("aggregations_binary", binaryParseElement)
.put("aggregationsBinary", binaryParseElement)
.put("aggs_binary", binaryParseElement)
.put("aggsBinary", binaryParseElement)
.build();
}
@Override
public void preProcess(SearchContext context) {
if (context.aggregations() != null) {
AggregationContext aggregationContext = new AggregationContext(context);
context.aggregations().aggregationContext(aggregationContext);
List<Aggregator> collectors = new ArrayList<>();
Aggregator[] aggregators = context.aggregations().factories().createTopLevelAggregators(aggregationContext);
for (int i = 0; i < aggregators.length; i++) {
if (!(aggregators[i] instanceof GlobalAggregator)) {
Aggregator aggregator = aggregators[i];
if (aggregator.shouldCollect()) {
collectors.add(aggregator);
}
}
}
context.aggregations().aggregators(aggregators);
if (!collectors.isEmpty()) {
context.searcher().addMainQueryCollector(new AggregationsCollector(collectors, aggregationContext));
}
aggregationContext.setNextReader(context.searcher().getIndexReader().getContext());
}
}
@Override
public void execute(SearchContext context) throws ElasticsearchException {
if (context.aggregations() == null) {
context.queryResult().aggregations(null);
return;
}
if (context.queryResult().aggregations() != null) {
// no need to compute the aggs twice, they should be computed on a per context basis
return;
}
Aggregator[] aggregators = context.aggregations().aggregators();
List<Aggregator> globals = new ArrayList<>();
for (int i = 0; i < aggregators.length; i++) {
if (aggregators[i] instanceof GlobalAggregator) {
globals.add(aggregators[i]);
}
}
// optimize the global collector based execution
if (!globals.isEmpty()) {
AggregationsCollector collector = new AggregationsCollector(globals, context.aggregations().aggregationContext());
Query query = new ConstantScoreQuery(Queries.MATCH_ALL_FILTER);
Filter searchFilter = context.searchFilter(context.types());
if (searchFilter != null) {
query = new FilteredQuery(query, searchFilter);
}
try {
context.searcher().search(query, collector);
collector.postCollection();
} catch (Exception e) {
throw new QueryPhaseExecutionException(context, "Failed to execute global aggregators", e);
}
}
List<InternalAggregation> aggregations = new ArrayList<>(aggregators.length);
for (Aggregator aggregator : context.aggregations().aggregators()) {
aggregations.add(aggregator.buildAggregation(0));
}
context.queryResult().aggregations(new InternalAggregations(aggregations));
// disable aggregations so that they don't run on next pages in case of scrolling
context.aggregations(null);
}
public static class AggregationsCollector extends SimpleCollector implements XCollector {
private final AggregationContext aggregationContext;
private final Aggregator[] collectors;
public AggregationsCollector(Collection<Aggregator> collectors, AggregationContext aggregationContext) {
this.collectors = collectors.toArray(new Aggregator[collectors.size()]);
this.aggregationContext = aggregationContext;
}
@Override
public void setScorer(Scorer scorer) throws IOException {
aggregationContext.setScorer(scorer);
}
@Override
public void collect(int doc) throws IOException {
for (Aggregator collector : collectors) {
collector.collect(doc, 0);
}
}
@Override
public void doSetNextReader(LeafReaderContext context) throws IOException {
aggregationContext.setNextReader(context);
}
@Override
public boolean acceptsDocsOutOfOrder() {
return !aggregationContext.scoreDocsInOrder();
}
@Override
public void postCollection() throws IOException {
for (Aggregator collector : collectors) {
collector.postCollection();
}
}
}
}