org.elasticsearch.search.query.QueryCollectorContext Maven / Gradle / Ivy
/*
* Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
* or more contributor license agreements. Licensed under the Elastic License
* 2.0 and the Server Side Public License, v 1; you may not use this file except
* in compliance with, at your election, the Elastic License 2.0 or the Server
* Side Public License, v 1.
*/
package org.elasticsearch.search.query;
import org.apache.lucene.search.Collector;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.MultiCollector;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.ScoreMode;
import org.apache.lucene.search.SimpleCollector;
import org.apache.lucene.search.Weight;
import org.elasticsearch.common.lucene.MinimumScoreCollector;
import org.elasticsearch.common.lucene.search.FilteredCollector;
import org.elasticsearch.search.profile.query.InternalProfileCollector;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
import static org.elasticsearch.search.profile.query.CollectorResult.REASON_SEARCH_MIN_SCORE;
import static org.elasticsearch.search.profile.query.CollectorResult.REASON_SEARCH_MULTI;
import static org.elasticsearch.search.profile.query.CollectorResult.REASON_SEARCH_POST_FILTER;
import static org.elasticsearch.search.profile.query.CollectorResult.REASON_SEARCH_TERMINATE_AFTER_COUNT;
abstract class QueryCollectorContext {
private static final Collector EMPTY_COLLECTOR = new SimpleCollector() {
@Override
public void collect(int doc) {}
@Override
public ScoreMode scoreMode() {
return ScoreMode.COMPLETE_NO_SCORES;
}
};
private String profilerName;
QueryCollectorContext(String profilerName) {
this.profilerName = profilerName;
}
/**
* Creates a collector that delegates documents to the provided in
collector.
* @param in The delegate collector
*/
abstract Collector create(Collector in) throws IOException;
/**
* Wraps this collector with a profiler
*/
protected InternalProfileCollector createWithProfiler(InternalProfileCollector in) throws IOException {
final Collector collector = create(in);
return new InternalProfileCollector(collector, profilerName, in != null ? Collections.singletonList(in) : Collections.emptyList());
}
/**
* Post-process result
after search execution.
*
* @param result The query search result to populate
*/
void postProcess(QuerySearchResult result) throws IOException {}
/**
* Creates the collector tree from the provided collectors
* @param collectors Ordered list of collector context
*/
static Collector createQueryCollector(List collectors) throws IOException {
Collector collector = null;
for (QueryCollectorContext ctx : collectors) {
collector = ctx.create(collector);
}
return collector;
}
/**
* Creates the collector tree from the provided collectors
and wraps each collector with a profiler
* @param collectors Ordered list of collector context
*/
static InternalProfileCollector createQueryCollectorWithProfiler(List collectors) throws IOException {
InternalProfileCollector collector = null;
for (QueryCollectorContext ctx : collectors) {
collector = ctx.createWithProfiler(collector);
}
return collector;
}
/**
* Filters documents with a query score greater than minScore
* @param minScore The minimum score filter
*/
static QueryCollectorContext createMinScoreCollectorContext(float minScore) {
return new QueryCollectorContext(REASON_SEARCH_MIN_SCORE) {
@Override
Collector create(Collector in) {
return new MinimumScoreCollector(in, minScore);
}
};
}
/**
* Filters documents based on the provided query
*/
static QueryCollectorContext createFilteredCollectorContext(IndexSearcher searcher, Query query) {
return new QueryCollectorContext(REASON_SEARCH_POST_FILTER) {
@Override
Collector create(Collector in) throws IOException {
final Weight filterWeight = searcher.createWeight(searcher.rewrite(query), ScoreMode.COMPLETE_NO_SCORES, 1f);
return new FilteredCollector(in, filterWeight);
}
};
}
/**
* Creates a multi collector from the provided subs
*/
static QueryCollectorContext createMultiCollectorContext(Collection subs) {
return new QueryCollectorContext(REASON_SEARCH_MULTI) {
@Override
Collector create(Collector in) {
List subCollectors = new ArrayList<>();
subCollectors.add(in);
subCollectors.addAll(subs);
return MultiCollector.wrap(subCollectors);
}
@Override
protected InternalProfileCollector createWithProfiler(InternalProfileCollector in) {
final List subCollectors = new ArrayList<>();
subCollectors.add(in);
if (subs.stream().anyMatch((col) -> col instanceof InternalProfileCollector == false)) {
throw new IllegalArgumentException("non-profiling collector");
}
for (Collector collector : subs) {
subCollectors.add((InternalProfileCollector) collector);
}
final Collector collector = MultiCollector.wrap(subCollectors);
return new InternalProfileCollector(collector, REASON_SEARCH_MULTI, subCollectors);
}
};
}
/**
* Creates collector limiting the collection to the first numHits
documents
*/
static QueryCollectorContext createEarlyTerminationCollectorContext(int numHits) {
return new QueryCollectorContext(REASON_SEARCH_TERMINATE_AFTER_COUNT) {
private Collector collector;
/**
* Creates a {@link MultiCollector} to ensure that the {@link EarlyTerminatingCollector}
* can terminate the collection independently of the provided in
{@link Collector}.
*/
@Override
Collector create(Collector in) {
assert collector == null;
List subCollectors = new ArrayList<>();
subCollectors.add(new EarlyTerminatingCollector(EMPTY_COLLECTOR, numHits, true));
subCollectors.add(in);
this.collector = MultiCollector.wrap(subCollectors);
return collector;
}
};
}
}