/*
* 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.search.MatchNoDocsQuery;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.join.BitSetProducer;
import org.apache.lucene.search.join.ScoreMode;
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.search.Queries;
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 java.io.IOException;
import java.util.Locale;
import java.util.Map;
import java.util.Objects;
public class NestedQueryBuilder extends AbstractQueryBuilder<NestedQueryBuilder> {
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 innerHit, boolean ignoreUnmapped) {
this.innerHitBuilder = new InnerHitBuilder(innerHit, path, query, 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;
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(QueryParseContext parseContext) throws IOException {
XContentParser parser = parseContext.parser();
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)) {
query = parseContext.parseInnerQueryBuilder();
} else if (INNER_HITS_FIELD.match(currentFieldName)) {
innerHitBuilder = InnerHitBuilder.fromXContent(parseContext);
} else {
throw new ParsingException(parser.getTokenLocation(), "[nested] query does not support [" + currentFieldName + "]");
}
} else if (token.isValue()) {
if (PATH_FIELD.match(currentFieldName)) {
path = parser.text();
} else if (AbstractQueryBuilder.BOOST_FIELD.match(currentFieldName)) {
boost = parser.floatValue();
} else if (IGNORE_UNMAPPED_FIELD.match(currentFieldName)) {
ignoreUnmapped = parser.booleanValue();
} else if (SCORE_MODE_FIELD.match(currentFieldName)) {
scoreMode = parseScoreMode(parser.text());
} else if (AbstractQueryBuilder.NAME_FIELD.match(currentFieldName)) {
queryName = parser.text();
} else {
throw new ParsingException(parser.getTokenLocation(), "[nested] query does not support [" + currentFieldName + "]");
}
}
}
NestedQueryBuilder queryBuilder = new NestedQueryBuilder(path, query, scoreMode)
.ignoreUnmapped(ignoreUnmapped)
.queryName(queryName)
.boost(boost);
if (innerHitBuilder != null) {
queryBuilder.innerHit(innerHitBuilder, ignoreUnmapped);
}
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 {
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());
} 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) {
InnerHitBuilder rewrittenInnerHit = InnerHitBuilder.rewrite(innerHitBuilder, rewrittenQuery);
NestedQueryBuilder nestedQuery = new NestedQueryBuilder(path, rewrittenQuery, scoreMode, rewrittenInnerHit);
nestedQuery.ignoreUnmapped(ignoreUnmapped);
return nestedQuery;
}
return this;
}
@Override
protected void extractInnerHitBuilders(Map<String, InnerHitBuilder> innerHits) {
if (innerHitBuilder != null) {
innerHitBuilder.inlineInnerHits(innerHits);
}
}
}