Visit the subquery builder recursively (#17953) (#18023)

* visit the subquery



* Fix visit method of constant score query and function score query to iterate recursively



---------


(cherry picked from commit b9046eb)

Signed-off-by: Varun Jain <[email protected]>
Signed-off-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>

Author: opensearch-trigger-bot[bot]

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

@@ -188,7 +188,9 @@ protected void extractInnerHitBuilders(Map<String, InnerHitContextBuilder> inner
     @Override
     public void visit(QueryBuilderVisitor visitor) {
         visitor.accept(this);
-        visitor.getChildVisitor(BooleanClause.Occur.FILTER).accept(filterBuilder);
+        if (filterBuilder != null) {
+            filterBuilder.visit(visitor.getChildVisitor(BooleanClause.Occur.FILTER));
+        }
     }
 
 }

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

@@ -254,7 +254,7 @@ public void visit(QueryBuilderVisitor visitor) {
         if (queries.isEmpty() == false) {
             QueryBuilderVisitor subVisitor = visitor.getChildVisitor(BooleanClause.Occur.SHOULD);
             for (QueryBuilder subQb : queries) {
-                subVisitor.accept(subQb);
+                subQb.visit(subVisitor);
             }
         }
     }

server/src/main/java/org/opensearch/index/query/functionscore/FunctionScoreQueryBuilder.java

@@ -711,7 +711,7 @@ private static String parseFiltersAndFunctions(
     public void visit(QueryBuilderVisitor visitor) {
         visitor.accept(this);
         if (query != null) {
-            visitor.getChildVisitor(BooleanClause.Occur.MUST).accept(query);
+            query.visit(visitor.getChildVisitor(BooleanClause.Occur.MUST));
         }
     }
 }