SERVER-39166 $graphLookup should force a pipeline to split in sharded cluster

1 files changed, 9 insertions, 1 deletions

diff --git a/src/mongo/db/pipeline/document_source_graph_lookup.h b/src/mongo/db/pipeline/document_source_graph_lookup.h
index cc186225ce8..5f1af60d2ce 100644
--- a/src/mongo/db/pipeline/document_source_graph_lookup.h
+++ b/src/mongo/db/pipeline/document_source_graph_lookup.h
@@ -38,7 +38,7 @@
 
 namespace mongo {
 
-class DocumentSourceGraphLookUp final : public DocumentSource {
+class DocumentSourceGraphLookUp final : public DocumentSource, public NeedsMergerDocumentSource {
 public:
     static std::unique_ptr<LiteParsedDocumentSourceForeignCollections> liteParse(
         const AggregationRequest& request, const BSONElement& spec);
@@ -72,6 +72,14 @@ public:
         return DepsTracker::State::SEE_NEXT;
     };
 
+    boost::intrusive_ptr<DocumentSource> getShardSource() final {
+        return nullptr;
+    }
+
+    MergingLogic mergingLogic() final {
+        return {this};
+    }
+
     void addInvolvedCollections(std::vector<NamespaceString>* collections) const final {
         collections->push_back(_from);
     }