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* 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.highlight;
import com.google.common.collect.Maps;
import org.apache.lucene.search.highlight.Encoder;
import org.apache.lucene.search.vectorhighlight.*;
import org.apache.lucene.search.vectorhighlight.FieldPhraseList.WeightedPhraseInfo;
import org.elasticsearch.ElasticsearchIllegalArgumentException;
import org.elasticsearch.common.inject.Inject;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.text.StringText;
import org.elasticsearch.index.mapper.FieldMapper;
import org.elasticsearch.search.fetch.FetchPhaseExecutionException;
import org.elasticsearch.search.fetch.FetchSubPhase;
import org.elasticsearch.search.highlight.vectorhighlight.SimpleFragmentsBuilder;
import org.elasticsearch.search.highlight.vectorhighlight.SourceScoreOrderFragmentsBuilder;
import org.elasticsearch.search.highlight.vectorhighlight.SourceSimpleFragmentsBuilder;
import org.elasticsearch.search.internal.SearchContext;
import java.util.Collections;
import java.util.Map;
/**
*
*/
public class FastVectorHighlighter implements Highlighter {
private static final SimpleBoundaryScanner DEFAULT_BOUNDARY_SCANNER = new SimpleBoundaryScanner();
private static final String CACHE_KEY = "highlight-fsv";
private final Boolean termVectorMultiValue;
@Inject
public FastVectorHighlighter(Settings settings) {
this.termVectorMultiValue = settings.getAsBoolean("search.highlight.term_vector_multi_value", true);
}
@Override
public String[] names() {
return new String[]{"fvh", "fast-vector-highlighter"};
}
@Override
public HighlightField highlight(HighlighterContext highlighterContext) {
SearchContextHighlight.Field field = highlighterContext.field;
SearchContext context = highlighterContext.context;
FetchSubPhase.HitContext hitContext = highlighterContext.hitContext;
FieldMapper<?> mapper = highlighterContext.mapper;
if (!(mapper.fieldType().storeTermVectors() && mapper.fieldType().storeTermVectorOffsets() && mapper.fieldType().storeTermVectorPositions())) {
throw new ElasticsearchIllegalArgumentException("the field [" + highlighterContext.fieldName + "] should be indexed with term vector with position offsets to be used with fast vector highlighter");
}
Encoder encoder = field.fieldOptions().encoder().equals("html") ? HighlightUtils.Encoders.HTML : HighlightUtils.Encoders.DEFAULT;
if (!hitContext.cache().containsKey(CACHE_KEY)) {
hitContext.cache().put(CACHE_KEY, new HighlighterEntry());
}
HighlighterEntry cache = (HighlighterEntry) hitContext.cache().get(CACHE_KEY);
try {
FieldQuery fieldQuery;
if (field.fieldOptions().requireFieldMatch()) {
if (cache.fieldMatchFieldQuery == null) {
// we use top level reader to rewrite the query against all readers, with use caching it across hits (and across readers...)
cache.fieldMatchFieldQuery = new CustomFieldQuery(highlighterContext.query.originalQuery(), hitContext.topLevelReader(), true, field.fieldOptions().requireFieldMatch());
}
fieldQuery = cache.fieldMatchFieldQuery;
} else {
if (cache.noFieldMatchFieldQuery == null) {
// we use top level reader to rewrite the query against all readers, with use caching it across hits (and across readers...)
cache.noFieldMatchFieldQuery = new CustomFieldQuery(highlighterContext.query.originalQuery(), hitContext.topLevelReader(), true, field.fieldOptions().requireFieldMatch());
}
fieldQuery = cache.noFieldMatchFieldQuery;
}
MapperHighlightEntry entry = cache.mappers.get(mapper);
if (entry == null) {
FragListBuilder fragListBuilder;
BaseFragmentsBuilder fragmentsBuilder;
BoundaryScanner boundaryScanner = DEFAULT_BOUNDARY_SCANNER;
if (field.fieldOptions().boundaryMaxScan() != SimpleBoundaryScanner.DEFAULT_MAX_SCAN || field.fieldOptions().boundaryChars() != SimpleBoundaryScanner.DEFAULT_BOUNDARY_CHARS) {
boundaryScanner = new SimpleBoundaryScanner(field.fieldOptions().boundaryMaxScan(), field.fieldOptions().boundaryChars());
}
boolean forceSource = context.highlight().forceSource(field);
if (field.fieldOptions().numberOfFragments() == 0) {
fragListBuilder = new SingleFragListBuilder();
if (!forceSource && mapper.fieldType().stored()) {
fragmentsBuilder = new SimpleFragmentsBuilder(mapper, field.fieldOptions().preTags(), field.fieldOptions().postTags(), boundaryScanner);
} else {
fragmentsBuilder = new SourceSimpleFragmentsBuilder(mapper, context, hitContext, field.fieldOptions().preTags(), field.fieldOptions().postTags(), boundaryScanner);
}
} else {
fragListBuilder = field.fieldOptions().fragmentOffset() == -1 ? new SimpleFragListBuilder() : new SimpleFragListBuilder(field.fieldOptions().fragmentOffset());
if (field.fieldOptions().scoreOrdered()) {
if (!forceSource && mapper.fieldType().stored()) {
fragmentsBuilder = new ScoreOrderFragmentsBuilder(field.fieldOptions().preTags(), field.fieldOptions().postTags(), boundaryScanner);
} else {
fragmentsBuilder = new SourceScoreOrderFragmentsBuilder(mapper, context, hitContext, field.fieldOptions().preTags(), field.fieldOptions().postTags(), boundaryScanner);
}
} else {
if (!forceSource && mapper.fieldType().stored()) {
fragmentsBuilder = new SimpleFragmentsBuilder(mapper, field.fieldOptions().preTags(), field.fieldOptions().postTags(), boundaryScanner);
} else {
fragmentsBuilder = new SourceSimpleFragmentsBuilder(mapper, context, hitContext, field.fieldOptions().preTags(), field.fieldOptions().postTags(), boundaryScanner);
}
}
}
fragmentsBuilder.setDiscreteMultiValueHighlighting(termVectorMultiValue);
entry = new MapperHighlightEntry();
entry.fragListBuilder = fragListBuilder;
entry.fragmentsBuilder = fragmentsBuilder;
if (cache.fvh == null) {
// parameters to FVH are not requires since:
// first two booleans are not relevant since they are set on the CustomFieldQuery (phrase and fieldMatch)
// fragment builders are used explicitly
cache.fvh = new org.apache.lucene.search.vectorhighlight.FastVectorHighlighter();
}
CustomFieldQuery.highlightFilters.set(field.fieldOptions().highlightFilter());
cache.mappers.put(mapper, entry);
}
cache.fvh.setPhraseLimit(field.fieldOptions().phraseLimit());
String[] fragments;
// a HACK to make highlighter do highlighting, even though its using the single frag list builder
int numberOfFragments = field.fieldOptions().numberOfFragments() == 0 ? Integer.MAX_VALUE : field.fieldOptions().numberOfFragments();
int fragmentCharSize = field.fieldOptions().numberOfFragments() == 0 ? Integer.MAX_VALUE : field.fieldOptions().fragmentCharSize();
// we highlight against the low level reader and docId, because if we load source, we want to reuse it if possible
// Only send matched fields if they were requested to save time.
if (field.fieldOptions().matchedFields() != null && !field.fieldOptions().matchedFields().isEmpty()) {
fragments = cache.fvh.getBestFragments(fieldQuery, hitContext.reader(), hitContext.docId(), mapper.names().indexName(), field.fieldOptions().matchedFields(), fragmentCharSize,
numberOfFragments, entry.fragListBuilder, entry.fragmentsBuilder, field.fieldOptions().preTags(), field.fieldOptions().postTags(), encoder);
} else {
fragments = cache.fvh.getBestFragments(fieldQuery, hitContext.reader(), hitContext.docId(), mapper.names().indexName(), fragmentCharSize,
numberOfFragments, entry.fragListBuilder, entry.fragmentsBuilder, field.fieldOptions().preTags(), field.fieldOptions().postTags(), encoder);
}
if (fragments != null && fragments.length > 0) {
return new HighlightField(highlighterContext.fieldName, StringText.convertFromStringArray(fragments));
}
int noMatchSize = highlighterContext.field.fieldOptions().noMatchSize();
if (noMatchSize > 0) {
// Essentially we just request that a fragment is built from 0 to noMatchSize using the normal fragmentsBuilder
FieldFragList fieldFragList = new SimpleFieldFragList(-1 /*ignored*/);
fieldFragList.add(0, noMatchSize, Collections.<WeightedPhraseInfo>emptyList());
fragments = entry.fragmentsBuilder.createFragments(hitContext.reader(), hitContext.docId(), mapper.names().indexName(),
fieldFragList, 1, field.fieldOptions().preTags(), field.fieldOptions().postTags(), encoder);
if (fragments != null && fragments.length > 0) {
return new HighlightField(highlighterContext.fieldName, StringText.convertFromStringArray(fragments));
}
}
return null;
} catch (Exception e) {
throw new FetchPhaseExecutionException(context, "Failed to highlight field [" + highlighterContext.fieldName + "]", e);
}
}
private class MapperHighlightEntry {
public FragListBuilder fragListBuilder;
public FragmentsBuilder fragmentsBuilder;
public org.apache.lucene.search.highlight.Highlighter highlighter;
}
private class HighlighterEntry {
public org.apache.lucene.search.vectorhighlight.FastVectorHighlighter fvh;
public FieldQuery noFieldMatchFieldQuery;
public FieldQuery fieldMatchFieldQuery;
public Map<FieldMapper, MapperHighlightEntry> mappers = Maps.newHashMap();
}
}