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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.functionscore.fieldvaluefactor;
import org.apache.lucene.document.FieldType;
import org.elasticsearch.ElasticsearchException;
import org.elasticsearch.common.lucene.search.function.FieldValueFactorFunction;
import org.elasticsearch.common.lucene.search.function.ScoreFunction;
import org.elasticsearch.common.xcontent.XContentParser;
import org.elasticsearch.index.fielddata.IndexNumericFieldData;
import org.elasticsearch.index.fielddata.plain.DoubleArrayIndexFieldData;
import org.elasticsearch.index.mapper.FieldMapper;
import org.elasticsearch.index.mapper.MappedFieldType;
import org.elasticsearch.index.query.QueryParseContext;
import org.elasticsearch.index.query.QueryParsingException;
import org.elasticsearch.index.query.functionscore.ScoreFunctionParser;
import org.elasticsearch.search.internal.SearchContext;
import java.io.IOException;
import java.util.Locale;
/**
* Parses out a function_score function that looks like:
*
* <pre>
* {
* "field_value_factor": {
* "field": "myfield",
* "factor": 1.5,
* "modifier": "square",
* "missing": 1
* }
* }
* </pre>
*/
public class FieldValueFactorFunctionParser implements ScoreFunctionParser {
public static String[] NAMES = { "field_value_factor", "fieldValueFactor" };
@Override
public ScoreFunction parse(QueryParseContext parseContext, XContentParser parser) throws IOException, QueryParsingException {
String currentFieldName = null;
String field = null;
float boostFactor = 1;
FieldValueFactorFunction.Modifier modifier = FieldValueFactorFunction.Modifier.NONE;
Double missing = null;
XContentParser.Token token;
while ((token = parser.nextToken()) != XContentParser.Token.END_OBJECT) {
if (token == XContentParser.Token.FIELD_NAME) {
currentFieldName = parser.currentName();
} else if (token.isValue()) {
if ("field".equals(currentFieldName)) {
field = parser.text();
} else if ("factor".equals(currentFieldName)) {
boostFactor = parser.floatValue();
} else if ("modifier".equals(currentFieldName)) {
modifier = FieldValueFactorFunction.Modifier.valueOf(parser.text().toUpperCase(Locale.ROOT));
} else if ("missing".equals(currentFieldName)) {
missing = parser.doubleValue();
} else {
throw new QueryParsingException(parseContext, NAMES[0] + " query does not support [" + currentFieldName + "]");
}
} else if("factor".equals(currentFieldName) && (token == XContentParser.Token.START_ARRAY || token == XContentParser.Token.START_OBJECT)) {
throw new QueryParsingException(parseContext, "[" + NAMES[0] + "] field 'factor' does not support lists or objects");
}
}
if (field == null) {
throw new QueryParsingException(parseContext, "[" + NAMES[0] + "] required field 'field' missing");
}
SearchContext searchContext = SearchContext.current();
MappedFieldType fieldType = searchContext.mapperService().smartNameFieldType(field);
IndexNumericFieldData fieldData = null;
if (fieldType == null) {
if(missing == null) {
throw new ElasticsearchException("Unable to find a field mapper for field [" + field + "]. No 'missing' value defined.");
}
} else {
fieldData = searchContext.fieldData().getForField(fieldType);
}
return new FieldValueFactorFunction(field, boostFactor, modifier, missing, fieldData);
}
@Override
public String[] getNames() {
return NAMES;
}
}