/*
* Licensed to ElasticSearch and Shay Banon 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.sort;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.Lists;
import org.apache.lucene.search.Sort;
import org.apache.lucene.search.SortField;
import org.elasticsearch.common.Nullable;
import org.elasticsearch.common.xcontent.XContentParser;
import org.elasticsearch.index.mapper.FieldMapper;
import org.elasticsearch.search.SearchParseElement;
import org.elasticsearch.search.SearchParseException;
import org.elasticsearch.search.internal.SearchContext;
import java.util.List;
/**
*
*/
public class SortParseElement implements SearchParseElement {
private static final SortField SORT_SCORE = new SortField(null, SortField.SCORE);
private static final SortField SORT_SCORE_REVERSE = new SortField(null, SortField.SCORE, true);
private static final SortField SORT_DOC = new SortField(null, SortField.DOC);
private static final SortField SORT_DOC_REVERSE = new SortField(null, SortField.DOC, true);
public static final String SCORE_FIELD_NAME = "_score";
public static final String DOC_FIELD_NAME = "_doc";
private final ImmutableMap<String, SortParser> parsers;
public SortParseElement() {
ImmutableMap.Builder<String, SortParser> builder = ImmutableMap.builder();
addParser(builder, new ScriptSortParser());
addParser(builder, new GeoDistanceSortParser());
this.parsers = builder.build();
}
private void addParser(ImmutableMap.Builder<String, SortParser> parsers, SortParser parser) {
for (String name : parser.names()) {
parsers.put(name, parser);
}
}
@Override
public void parse(XContentParser parser, SearchContext context) throws Exception {
XContentParser.Token token = parser.currentToken();
List<SortField> sortFields = Lists.newArrayListWithCapacity(2);
if (token == XContentParser.Token.START_ARRAY) {
while ((token = parser.nextToken()) != XContentParser.Token.END_ARRAY) {
if (token == XContentParser.Token.START_OBJECT) {
addCompoundSortField(parser, context, sortFields);
} else if (token == XContentParser.Token.VALUE_STRING) {
addSortField(context, sortFields, parser.text(), false, false, null);
}
}
} else {
addCompoundSortField(parser, context, sortFields);
}
if (!sortFields.isEmpty()) {
// optimize if we just sort on score non reversed, we don't really need sorting
boolean sort;
if (sortFields.size() > 1) {
sort = true;
} else {
SortField sortField = sortFields.get(0);
if (sortField.getType() == SortField.SCORE && !sortField.getReverse()) {
sort = false;
} else {
sort = true;
}
}
if (sort) {
context.sort(new Sort(sortFields.toArray(new SortField[sortFields.size()])));
}
}
}
private void addCompoundSortField(XContentParser parser, SearchContext context, List<SortField> sortFields) throws Exception {
XContentParser.Token token;
while ((token = parser.nextToken()) != XContentParser.Token.END_OBJECT) {
if (token == XContentParser.Token.FIELD_NAME) {
String fieldName = parser.currentName();
boolean reverse = false;
String missing = null;
String innerJsonName = null;
boolean ignoreUnmapped = false;
token = parser.nextToken();
if (token == XContentParser.Token.VALUE_STRING) {
String direction = parser.text();
if (direction.equals("asc")) {
reverse = SCORE_FIELD_NAME.equals(fieldName);
} else if (direction.equals("desc")) {
reverse = !SCORE_FIELD_NAME.equals(fieldName);
}
addSortField(context, sortFields, fieldName, reverse, ignoreUnmapped, missing);
} else {
if (parsers.containsKey(fieldName)) {
sortFields.add(parsers.get(fieldName).parse(parser, context));
} else {
while ((token = parser.nextToken()) != XContentParser.Token.END_OBJECT) {
if (token == XContentParser.Token.FIELD_NAME) {
innerJsonName = parser.currentName();
} else if (token.isValue()) {
if ("reverse".equals(innerJsonName)) {
reverse = parser.booleanValue();
} else if ("order".equals(innerJsonName)) {
if ("asc".equals(parser.text())) {
reverse = SCORE_FIELD_NAME.equals(fieldName);
} else if ("desc".equals(parser.text())) {
reverse = !SCORE_FIELD_NAME.equals(fieldName);
}
} else if ("missing".equals(innerJsonName)) {
missing = parser.textOrNull();
} else if ("ignore_unmapped".equals(innerJsonName) || "ignoreUnmapped".equals(innerJsonName)) {
ignoreUnmapped = parser.booleanValue();
}
}
}
addSortField(context, sortFields, fieldName, reverse, ignoreUnmapped, missing);
}
}
}
}
}
private void addSortField(SearchContext context, List<SortField> sortFields, String fieldName, boolean reverse, boolean ignoreUnmapped, @Nullable final String missing) {
if (SCORE_FIELD_NAME.equals(fieldName)) {
if (reverse) {
sortFields.add(SORT_SCORE_REVERSE);
} else {
sortFields.add(SORT_SCORE);
}
} else if (DOC_FIELD_NAME.equals(fieldName)) {
if (reverse) {
sortFields.add(SORT_DOC_REVERSE);
} else {
sortFields.add(SORT_DOC);
}
} else {
FieldMapper fieldMapper = context.smartNameFieldMapper(fieldName);
if (fieldMapper == null) {
if (ignoreUnmapped) {
return;
}
throw new SearchParseException(context, "No mapping found for [" + fieldName + "] in order to sort on");
}
sortFields.add(new SortField(fieldMapper.names().indexName(), fieldMapper.fieldDataType().newFieldComparatorSource(context.fieldDataCache(), missing), reverse));
}
}
}