org.opensearch.search.suggest.completion.CompletionSuggester Maven / Gradle / Ivy
/*
* SPDX-License-Identifier: Apache-2.0
*
* The OpenSearch Contributors require contributions made to
* this file be licensed under the Apache-2.0 license or a
* compatible open source license.
*/
/*
* 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
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/*
* Modifications Copyright OpenSearch Contributors. See
* GitHub history for details.
*/
package org.opensearch.search.suggest.completion;
import org.apache.lucene.index.LeafReaderContext;
import org.apache.lucene.search.BulkScorer;
import org.apache.lucene.search.CollectionTerminatedException;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Weight;
import org.apache.lucene.search.suggest.document.CompletionQuery;
import org.apache.lucene.search.suggest.document.TopSuggestDocs;
import org.apache.lucene.search.suggest.document.TopSuggestDocsCollector;
import org.apache.lucene.util.CharsRefBuilder;
import org.opensearch.common.text.Text;
import org.opensearch.index.mapper.CompletionFieldMapper;
import org.opensearch.search.suggest.Suggest;
import org.opensearch.search.suggest.Suggester;
import java.io.IOException;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.Set;
public class CompletionSuggester extends Suggester {
public static final CompletionSuggester INSTANCE = new CompletionSuggester();
private CompletionSuggester() {}
@Override
protected Suggest.Suggestion> innerExecute(
String name,
final CompletionSuggestionContext suggestionContext,
final IndexSearcher searcher,
CharsRefBuilder spare
) throws IOException {
if (suggestionContext.getFieldType() != null) {
final CompletionFieldMapper.CompletionFieldType fieldType = suggestionContext.getFieldType();
CompletionSuggestion completionSuggestion = emptySuggestion(name, suggestionContext, spare);
int shardSize = suggestionContext.getShardSize() != null ? suggestionContext.getShardSize() : suggestionContext.getSize();
TopSuggestGroupDocsCollector collector = new TopSuggestGroupDocsCollector(shardSize, suggestionContext.isSkipDuplicates());
suggest(searcher, suggestionContext.toQuery(), collector);
int numResult = 0;
for (TopSuggestDocs.SuggestScoreDoc suggestDoc : collector.get().scoreLookupDocs()) {
// collect contexts
Map> contexts = Collections.emptyMap();
if (fieldType.hasContextMappings()) {
List rawContexts = collector.getContexts(suggestDoc.doc);
if (rawContexts.size() > 0) {
contexts = fieldType.getContextMappings().getNamedContexts(rawContexts);
}
}
if (numResult++ < suggestionContext.getSize()) {
CompletionSuggestion.Entry.Option option = new CompletionSuggestion.Entry.Option(
suggestDoc.doc,
new Text(suggestDoc.key.toString()),
suggestDoc.score,
contexts
);
completionSuggestion.getEntries().get(0).addOption(option);
} else {
break;
}
}
return completionSuggestion;
}
return null;
}
private static void suggest(IndexSearcher searcher, CompletionQuery query, TopSuggestDocsCollector collector) throws IOException {
query = (CompletionQuery) query.rewrite(searcher.getIndexReader());
Weight weight = query.createWeight(searcher, collector.scoreMode(), 1f);
for (LeafReaderContext context : searcher.getIndexReader().leaves()) {
BulkScorer scorer = weight.bulkScorer(context);
if (scorer != null) {
try {
scorer.score(collector.getLeafCollector(context), context.reader().getLiveDocs());
} catch (CollectionTerminatedException e) {
// collection was terminated prematurely
// continue with the following leaf
}
}
}
}
@Override
protected CompletionSuggestion emptySuggestion(String name, CompletionSuggestionContext suggestion, CharsRefBuilder spare)
throws IOException {
CompletionSuggestion completionSuggestion = new CompletionSuggestion(name, suggestion.getSize(), suggestion.isSkipDuplicates());
spare.copyUTF8Bytes(suggestion.getText());
CompletionSuggestion.Entry completionSuggestEntry = new CompletionSuggestion.Entry(new Text(spare.toString()), 0, spare.length());
completionSuggestion.addTerm(completionSuggestEntry);
return completionSuggestion;
}
}