Fix object field exists query (#17843)

* Fix object field exists query

Signed-off-by: panguixin <panguixin@bytedance.com>

* catch uoe

Signed-off-by: panguixin <panguixin@bytedance.com>

* changelog

Signed-off-by: panguixin <panguixin@bytedance.com>

---------

Signed-off-by: panguixin <panguixin@bytedance.com>
Signed-off-by: Marc Handalian <marc.handalian@gmail.com>
Co-authored-by: Marc Handalian <marc.handalian@gmail.com>

Author: bugmakerrrrrr

CHANGELOG.md

@@ -31,6 +31,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - Fix simultaneously creating a snapshot and updating the repository can potentially trigger an infinite loop ([#17532](https://github.com/opensearch-project/OpenSearch/pull/17532))
 - Remove package org.opensearch.transport.grpc and replace with org.opensearch.plugin.transport.grpc ([#18031](https://github.com/opensearch-project/OpenSearch/pull/18031))
 - Fix the native plugin installation error cause by the pgp public key change ([#18147](https://github.com/opensearch-project/OpenSearch/pull/18147))
+- Fix object field exists query ([#17843](https://github.com/opensearch-project/OpenSearch/pull/17843))
 
 ### Security
 

modules/mapper-extras/src/test/java/org/opensearch/index/mapper/SearchAsYouTypeFieldMapperTests.java

@@ -577,7 +577,10 @@ public void testNestedExistsQuery() throws IOException {
         QueryShardContext queryShardContext = createQueryShardContext(mapperService);
         Query actual = new QueryStringQueryBuilder("field:*").toQuery(queryShardContext);
         Query expected = new ConstantScoreQuery(
-            new BooleanQuery.Builder().add(new FieldExistsQuery("field.nested_field"), BooleanClause.Occur.SHOULD).build()
+            new BooleanQuery.Builder().add(new FieldExistsQuery("field.nested_field"), BooleanClause.Occur.SHOULD)
+                .add(new FieldExistsQuery("field.nested_field._2gram"), BooleanClause.Occur.SHOULD)
+                .add(new FieldExistsQuery("field.nested_field._3gram"), BooleanClause.Occur.SHOULD)
+                .build()
         );
         assertEquals(expected, actual);
     }

server/src/main/java/org/opensearch/index/mapper/DerivedFieldType.java

@@ -477,7 +477,7 @@ public Query geoShapeQuery(Geometry shape, String fieldName, ShapeRelation relat
 
     @Override
     public Query existsQuery(QueryShardContext context) {
-        throw new IllegalArgumentException("Field [" + name() + "] of type [" + typeName() + "] does not support exist queries");
+        throw new UnsupportedOperationException("Field [" + name() + "] of type [" + typeName() + "] does not support exist queries");
     }
 
     @Override

server/src/main/java/org/opensearch/index/query/ExistsQueryBuilder.java

@@ -202,13 +202,13 @@ private static Query newObjectFieldExistsQuery(QueryShardContext context, String
         BooleanQuery.Builder booleanQuery = new BooleanQuery.Builder();
         Collection<String> fields = context.simpleMatchToIndexNames(objField + ".*");
         for (String field : fields) {
-            int dotPos = field.lastIndexOf('.');
-            if (dotPos > 0 && field.charAt(dotPos + 1) == '_') {
-                // This is a subfield (e.g. prefix) of a complex field type. Skip it.
-                continue;
+            try {
+                Query existsQuery = context.getMapperService().fieldType(field).existsQuery(context);
+                booleanQuery.add(existsQuery, Occur.SHOULD);
+            } catch (UnsupportedOperationException e) {
+                // ignore some subfields which not support exists query
+                // if none of the subfields support the exists query, this is equivalent to MatchNoDocsQuery
             }
-            Query existsQuery = context.getMapperService().fieldType(field).existsQuery(context);
-            booleanQuery.add(existsQuery, Occur.SHOULD);
         }
         return new ConstantScoreQuery(booleanQuery.build());
     }

server/src/test/java/org/opensearch/index/query/ExistsQueryBuilderTests.java

@@ -39,6 +39,9 @@
 import org.apache.lucene.search.MatchNoDocsQuery;
 import org.apache.lucene.search.Query;
 import org.apache.lucene.search.TermQuery;
+import org.opensearch.common.compress.CompressedXContent;
+import org.opensearch.core.xcontent.XContentBuilder;
+import org.opensearch.index.mapper.MapperService;
 import org.opensearch.test.AbstractQueryTestCase;
 
 import java.io.IOException;
@@ -47,10 +50,35 @@
 import java.util.List;
 import java.util.stream.Collectors;
 
+import static org.opensearch.common.xcontent.XContentFactory.jsonBuilder;
 import static org.hamcrest.CoreMatchers.equalTo;
 import static org.hamcrest.CoreMatchers.instanceOf;
 
 public class ExistsQueryBuilderTests extends AbstractQueryTestCase<ExistsQueryBuilder> {
+
+    @Override
+    protected void initializeAdditionalMappings(MapperService mapperService) throws IOException {
+        XContentBuilder mapping = jsonBuilder().startObject()
+            .startObject("_doc")
+            .startObject("properties")
+            .startObject("raw.keyword")
+            .field("type", "keyword")
+            .endObject()
+            .endObject()
+            .startObject("derived")
+            .startObject("raw.derived_keyword")
+            .field("type", "keyword")
+            .startObject("script")
+            .field("source", "emit(doc['raw.keyword'].value)")
+            .endObject()
+            .endObject()
+            .endObject()
+            .endObject()
+            .endObject();
+
+        mapperService.merge("_doc", new CompressedXContent(mapping.toString()), MapperService.MergeReason.MAPPING_UPDATE);
+    }
+
     @Override
     protected ExistsQueryBuilder doCreateTestQueryBuilder() {
         String fieldPattern;
@@ -144,4 +172,16 @@ public void testFromJson() throws IOException {
         assertEquals(json, 42.0, parsed.boost(), 0.0001);
         assertEquals(json, "user", parsed.fieldName());
     }
+
+    public void testObjectFieldWithDerivedSubField() throws IOException {
+        QueryShardContext shardContext = createShardContext();
+        final ExistsQueryBuilder queryBuilder1 = new ExistsQueryBuilder("raw.derived_keyword");
+        expectThrows(UnsupportedOperationException.class, () -> queryBuilder1.toQuery(shardContext));
+        final ExistsQueryBuilder queryBuilder2 = new ExistsQueryBuilder("raw");
+        Query actual = queryBuilder2.toQuery(shardContext);
+        Query expected = new ConstantScoreQuery(
+            new BooleanQuery.Builder().add(new FieldExistsQuery("raw.keyword"), BooleanClause.Occur.SHOULD).build()
+        );
+        assertEquals(expected, actual);
+    }
 }