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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.index.query;
import org.apache.lucene.index.LeafReaderContext;
import org.apache.lucene.index.ReaderUtil;
import org.apache.lucene.search.MatchNoDocsQuery;
import org.apache.lucene.search.MultiCollector;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.TopDocs;
import org.apache.lucene.search.TopDocsCollector;
import org.apache.lucene.search.TopFieldCollector;
import org.apache.lucene.search.TopScoreDocCollector;
import org.apache.lucene.search.TotalHitCountCollector;
import org.apache.lucene.search.TotalHits;
import org.apache.lucene.search.Weight;
import org.apache.lucene.search.join.BitSetProducer;
import org.apache.lucene.search.join.ParentChildrenBlockJoinQuery;
import org.apache.lucene.search.join.ScoreMode;
import org.elasticsearch.ElasticsearchException;
import org.elasticsearch.action.search.MaxScoreCollector;
import org.elasticsearch.common.ParseField;
import org.elasticsearch.common.ParsingException;
import org.elasticsearch.common.io.stream.StreamInput;
import org.elasticsearch.common.io.stream.StreamOutput;
import org.elasticsearch.common.lucene.Lucene;
import org.elasticsearch.common.lucene.search.Queries;
import org.elasticsearch.common.lucene.search.TopDocsAndMaxScore;
import org.elasticsearch.common.xcontent.XContentBuilder;
import org.elasticsearch.common.xcontent.XContentParser;
import org.elasticsearch.index.mapper.ObjectMapper;
import org.elasticsearch.index.search.ESToParentBlockJoinQuery;
import org.elasticsearch.index.search.NestedHelper;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.fetch.subphase.InnerHitsContext;
import org.elasticsearch.search.internal.SearchContext;
import java.io.IOException;
import java.util.HashMap;
import java.util.Locale;
import java.util.Map;
import java.util.Objects;
import static org.elasticsearch.search.SearchService.ALLOW_EXPENSIVE_QUERIES;
import static org.elasticsearch.search.fetch.subphase.InnerHitsContext.intersect;
public class NestedQueryBuilder extends AbstractQueryBuilder {
public static final String NAME = "nested";
/**
* The default value for ignore_unmapped.
*/
public static final boolean DEFAULT_IGNORE_UNMAPPED = false;
private static final ParseField SCORE_MODE_FIELD = new ParseField("score_mode");
private static final ParseField PATH_FIELD = new ParseField("path");
private static final ParseField QUERY_FIELD = new ParseField("query");
private static final ParseField INNER_HITS_FIELD = new ParseField("inner_hits");
private static final ParseField IGNORE_UNMAPPED_FIELD = new ParseField("ignore_unmapped");
private final String path;
private final ScoreMode scoreMode;
private final QueryBuilder query;
private InnerHitBuilder innerHitBuilder;
private boolean ignoreUnmapped = DEFAULT_IGNORE_UNMAPPED;
public NestedQueryBuilder(String path, QueryBuilder query, ScoreMode scoreMode) {
this(path, query, scoreMode, null);
}
private NestedQueryBuilder(String path, QueryBuilder query, ScoreMode scoreMode, InnerHitBuilder innerHitBuilder) {
this.path = requireValue(path, "[" + NAME + "] requires 'path' field");
this.query = requireValue(query, "[" + NAME + "] requires 'query' field");
this.scoreMode = requireValue(scoreMode, "[" + NAME + "] requires 'score_mode' field");
this.innerHitBuilder = innerHitBuilder;
}
/**
* Read from a stream.
*/
public NestedQueryBuilder(StreamInput in) throws IOException {
super(in);
path = in.readString();
scoreMode = ScoreMode.values()[in.readVInt()];
query = in.readNamedWriteable(QueryBuilder.class);
innerHitBuilder = in.readOptionalWriteable(InnerHitBuilder::new);
ignoreUnmapped = in.readBoolean();
}
@Override
protected void doWriteTo(StreamOutput out) throws IOException {
out.writeString(path);
out.writeVInt(scoreMode.ordinal());
out.writeNamedWriteable(query);
out.writeOptionalWriteable(innerHitBuilder);
out.writeBoolean(ignoreUnmapped);
}
/**
* Returns the nested query to execute.
*/
public QueryBuilder query() {
return query;
}
/**
* Returns inner hit definition in the scope of this query and reusing the defined type and query.
*/
public InnerHitBuilder innerHit() {
return innerHitBuilder;
}
public NestedQueryBuilder innerHit(InnerHitBuilder innerHitBuilder) {
this.innerHitBuilder = innerHitBuilder;
innerHitBuilder.setIgnoreUnmapped(ignoreUnmapped);
return this;
}
/**
* Returns how the scores from the matching child documents are mapped into the nested parent document.
*/
public ScoreMode scoreMode() {
return scoreMode;
}
/**
* Sets whether the query builder should ignore unmapped paths (and run a
* {@link MatchNoDocsQuery} in place of this query) or throw an exception if
* the path is unmapped.
*/
public NestedQueryBuilder ignoreUnmapped(boolean ignoreUnmapped) {
this.ignoreUnmapped = ignoreUnmapped;
if (innerHitBuilder != null) {
innerHitBuilder.setIgnoreUnmapped(ignoreUnmapped);
}
return this;
}
/**
* Gets whether the query builder will ignore unmapped fields (and run a
* {@link MatchNoDocsQuery} in place of this query) or throw an exception if
* the path is unmapped.
*/
public boolean ignoreUnmapped() {
return ignoreUnmapped;
}
@Override
protected void doXContent(XContentBuilder builder, Params params) throws IOException {
builder.startObject(NAME);
builder.field(QUERY_FIELD.getPreferredName());
query.toXContent(builder, params);
builder.field(PATH_FIELD.getPreferredName(), path);
builder.field(IGNORE_UNMAPPED_FIELD.getPreferredName(), ignoreUnmapped);
if (scoreMode != null) {
builder.field(SCORE_MODE_FIELD.getPreferredName(), scoreModeAsString(scoreMode));
}
printBoostAndQueryName(builder);
if (innerHitBuilder != null) {
builder.field(INNER_HITS_FIELD.getPreferredName(), innerHitBuilder, params);
}
builder.endObject();
}
public static NestedQueryBuilder fromXContent(XContentParser parser) throws IOException {
float boost = AbstractQueryBuilder.DEFAULT_BOOST;
ScoreMode scoreMode = ScoreMode.Avg;
String queryName = null;
QueryBuilder query = null;
String path = null;
String currentFieldName = null;
InnerHitBuilder innerHitBuilder = null;
boolean ignoreUnmapped = DEFAULT_IGNORE_UNMAPPED;
XContentParser.Token token;
while ((token = parser.nextToken()) != XContentParser.Token.END_OBJECT) {
if (token == XContentParser.Token.FIELD_NAME) {
currentFieldName = parser.currentName();
} else if (token == XContentParser.Token.START_OBJECT) {
if (QUERY_FIELD.match(currentFieldName, parser.getDeprecationHandler())) {
query = parseInnerQueryBuilder(parser);
} else if (INNER_HITS_FIELD.match(currentFieldName, parser.getDeprecationHandler())) {
innerHitBuilder = InnerHitBuilder.fromXContent(parser);
} else {
throw new ParsingException(parser.getTokenLocation(), "[nested] query does not support [" + currentFieldName + "]");
}
} else if (token.isValue()) {
if (PATH_FIELD.match(currentFieldName, parser.getDeprecationHandler())) {
path = parser.text();
} else if (AbstractQueryBuilder.BOOST_FIELD.match(currentFieldName, parser.getDeprecationHandler())) {
boost = parser.floatValue();
} else if (IGNORE_UNMAPPED_FIELD.match(currentFieldName, parser.getDeprecationHandler())) {
ignoreUnmapped = parser.booleanValue();
} else if (SCORE_MODE_FIELD.match(currentFieldName, parser.getDeprecationHandler())) {
scoreMode = parseScoreMode(parser.text());
} else if (AbstractQueryBuilder.NAME_FIELD.match(currentFieldName, parser.getDeprecationHandler())) {
queryName = parser.text();
} else {
throw new ParsingException(parser.getTokenLocation(), "[nested] query does not support [" + currentFieldName + "]");
}
}
}
NestedQueryBuilder queryBuilder = new NestedQueryBuilder(path, query, scoreMode, innerHitBuilder)
.ignoreUnmapped(ignoreUnmapped)
.queryName(queryName)
.boost(boost);
return queryBuilder;
}
public static ScoreMode parseScoreMode(String scoreModeString) {
if ("none".equals(scoreModeString)) {
return ScoreMode.None;
} else if ("min".equals(scoreModeString)) {
return ScoreMode.Min;
} else if ("max".equals(scoreModeString)) {
return ScoreMode.Max;
} else if ("avg".equals(scoreModeString)) {
return ScoreMode.Avg;
} else if ("sum".equals(scoreModeString)) {
return ScoreMode.Total;
}
throw new IllegalArgumentException("No score mode for child query [" + scoreModeString + "] found");
}
public static String scoreModeAsString(ScoreMode scoreMode) {
if (scoreMode == ScoreMode.Total) {
// Lucene uses 'total' but 'sum' is more consistent with other elasticsearch APIs
return "sum";
} else {
return scoreMode.name().toLowerCase(Locale.ROOT);
}
}
@Override
public final String getWriteableName() {
return NAME;
}
@Override
protected boolean doEquals(NestedQueryBuilder that) {
return Objects.equals(query, that.query)
&& Objects.equals(path, that.path)
&& Objects.equals(scoreMode, that.scoreMode)
&& Objects.equals(innerHitBuilder, that.innerHitBuilder)
&& Objects.equals(ignoreUnmapped, that.ignoreUnmapped);
}
@Override
protected int doHashCode() {
return Objects.hash(query, path, scoreMode, innerHitBuilder, ignoreUnmapped);
}
@Override
protected Query doToQuery(QueryShardContext context) throws IOException {
if (context.allowExpensiveQueries() == false) {
throw new ElasticsearchException("[joining] queries cannot be executed when '" +
ALLOW_EXPENSIVE_QUERIES.getKey() + "' is set to false.");
}
ObjectMapper nestedObjectMapper = context.getObjectMapper(path);
if (nestedObjectMapper == null) {
if (ignoreUnmapped) {
return new MatchNoDocsQuery();
} else {
throw new IllegalStateException("[" + NAME + "] failed to find nested object under path [" + path + "]");
}
}
if (!nestedObjectMapper.nested().isNested()) {
throw new IllegalStateException("[" + NAME + "] nested object under path [" + path + "] is not of nested type");
}
final BitSetProducer parentFilter;
Query innerQuery;
ObjectMapper objectMapper = context.nestedScope().getObjectMapper();
if (objectMapper == null) {
parentFilter = context.bitsetFilter(Queries.newNonNestedFilter(context.indexVersionCreated()));
} else {
parentFilter = context.bitsetFilter(objectMapper.nestedTypeFilter());
}
try {
context.nestedScope().nextLevel(nestedObjectMapper);
innerQuery = this.query.toQuery(context);
} finally {
context.nestedScope().previousLevel();
}
// ToParentBlockJoinQuery requires that the inner query only matches documents
// in its child space
if (new NestedHelper(context.getMapperService()).mightMatchNonNestedDocs(innerQuery, path)) {
innerQuery = Queries.filtered(innerQuery, nestedObjectMapper.nestedTypeFilter());
}
return new ESToParentBlockJoinQuery(innerQuery, parentFilter, scoreMode,
objectMapper == null ? null : objectMapper.fullPath());
}
@Override
protected QueryBuilder doRewrite(QueryRewriteContext queryRewriteContext) throws IOException {
QueryBuilder rewrittenQuery = query.rewrite(queryRewriteContext);
if (rewrittenQuery != query) {
NestedQueryBuilder nestedQuery = new NestedQueryBuilder(path, rewrittenQuery, scoreMode, innerHitBuilder);
nestedQuery.ignoreUnmapped(ignoreUnmapped);
return nestedQuery;
}
return this;
}
@Override
public void extractInnerHitBuilders(Map innerHits) {
if (innerHitBuilder != null) {
String name = innerHitBuilder.getName() != null ? innerHitBuilder.getName() : path;
if (innerHits.containsKey(name)) {
throw new IllegalArgumentException("[inner_hits] already contains an entry for key [" + name + "]");
}
Map children = new HashMap<>();
InnerHitContextBuilder.extractInnerHits(query, children);
InnerHitContextBuilder innerHitContextBuilder = new NestedInnerHitContextBuilder(path, query, innerHitBuilder, children);
innerHits.put(name, innerHitContextBuilder);
}
}
static class NestedInnerHitContextBuilder extends InnerHitContextBuilder {
private final String path;
NestedInnerHitContextBuilder(String path, QueryBuilder query, InnerHitBuilder innerHitBuilder,
Map children) {
super(query, innerHitBuilder, children);
this.path = path;
}
@Override
protected void doBuild(SearchContext parentSearchContext,
InnerHitsContext innerHitsContext) throws IOException {
QueryShardContext queryShardContext = parentSearchContext.getQueryShardContext();
ObjectMapper nestedObjectMapper = queryShardContext.getObjectMapper(path);
if (nestedObjectMapper == null) {
if (innerHitBuilder.isIgnoreUnmapped() == false) {
throw new IllegalStateException("[" + query.getName() + "] no mapping found for type [" + path + "]");
} else {
return;
}
}
String name = innerHitBuilder.getName() != null ? innerHitBuilder.getName() : nestedObjectMapper.fullPath();
ObjectMapper parentObjectMapper = queryShardContext.nestedScope().nextLevel(nestedObjectMapper);
NestedInnerHitSubContext nestedInnerHits = new NestedInnerHitSubContext(
name, parentSearchContext, parentObjectMapper, nestedObjectMapper
);
setupInnerHitsContext(queryShardContext, nestedInnerHits);
queryShardContext.nestedScope().previousLevel();
innerHitsContext.addInnerHitDefinition(nestedInnerHits);
}
}
static final class NestedInnerHitSubContext extends InnerHitsContext.InnerHitSubContext {
private final ObjectMapper parentObjectMapper;
private final ObjectMapper childObjectMapper;
NestedInnerHitSubContext(String name, SearchContext context, ObjectMapper parentObjectMapper, ObjectMapper childObjectMapper) {
super(name, context);
this.parentObjectMapper = parentObjectMapper;
this.childObjectMapper = childObjectMapper;
}
@Override
public void seqNoAndPrimaryTerm(boolean seqNoAndPrimaryTerm) {
assert seqNoAndPrimaryTerm() == false;
if (seqNoAndPrimaryTerm) {
throw new UnsupportedOperationException("nested documents are not assigned sequence numbers");
}
}
@Override
public TopDocsAndMaxScore[] topDocs(SearchHit[] hits) throws IOException {
Weight innerHitQueryWeight = createInnerHitQueryWeight();
TopDocsAndMaxScore[] result = new TopDocsAndMaxScore[hits.length];
for (int i = 0; i < hits.length; i++) {
SearchHit hit = hits[i];
Query rawParentFilter;
if (parentObjectMapper == null) {
rawParentFilter = Queries.newNonNestedFilter(context.indexShard().indexSettings().getIndexVersionCreated());
} else {
rawParentFilter = parentObjectMapper.nestedTypeFilter();
}
int parentDocId = hit.docId();
final int readerIndex = ReaderUtil.subIndex(parentDocId, searcher().getIndexReader().leaves());
// With nested inner hits the nested docs are always in the same segement, so need to use the other segments
LeafReaderContext ctx = searcher().getIndexReader().leaves().get(readerIndex);
Query childFilter = childObjectMapper.nestedTypeFilter();
BitSetProducer parentFilter = context.bitsetFilterCache().getBitSetProducer(rawParentFilter);
Query q = new ParentChildrenBlockJoinQuery(parentFilter, childFilter, parentDocId);
Weight weight = context.searcher().createWeight(context.searcher().rewrite(q),
org.apache.lucene.search.ScoreMode.COMPLETE_NO_SCORES, 1f);
if (size() == 0) {
TotalHitCountCollector totalHitCountCollector = new TotalHitCountCollector();
intersect(weight, innerHitQueryWeight, totalHitCountCollector, ctx);
result[i] = new TopDocsAndMaxScore(new TopDocs(new TotalHits(totalHitCountCollector.getTotalHits(),
TotalHits.Relation.EQUAL_TO), Lucene.EMPTY_SCORE_DOCS), Float.NaN);
} else {
int topN = Math.min(from() + size(), context.searcher().getIndexReader().maxDoc());
TopDocsCollector topDocsCollector;
MaxScoreCollector maxScoreCollector = null;
if (sort() != null) {
topDocsCollector = TopFieldCollector.create(sort().sort, topN, Integer.MAX_VALUE);
if (trackScores()) {
maxScoreCollector = new MaxScoreCollector();
}
} else {
topDocsCollector = TopScoreDocCollector.create(topN, Integer.MAX_VALUE);
maxScoreCollector = new MaxScoreCollector();
}
try {
intersect(weight, innerHitQueryWeight, MultiCollector.wrap(topDocsCollector, maxScoreCollector), ctx);
} finally {
clearReleasables(Lifetime.COLLECTION);
}
TopDocs td = topDocsCollector.topDocs(from(), size());
float maxScore = Float.NaN;
if (maxScoreCollector != null) {
maxScore = maxScoreCollector.getMaxScore();
}
result[i] = new TopDocsAndMaxScore(td, maxScore);
}
}
return result;
}
}
}