fix(opensearch): Update should clear projects and personas when they are empty

backend/onyx/document_index/opensearch/opensearch_document_index.py

@@ -433,12 +433,16 @@ def update_single(
             hidden=fields.hidden if fields else None,
             project_ids=(
                 set(user_fields.user_projects)
-                if user_fields and user_fields.user_projects
+                # NOTE: Empty user_projects is semantically different from None
+                # user_projects.
+                if user_fields and user_fields.user_projects is not None
                 else None
             ),
             persona_ids=(
                 set(user_fields.personas)
-                if user_fields and user_fields.personas
+                # NOTE: Empty personas is semantically different from None
+                # personas.
+                if user_fields and user_fields.personas is not None
                 else None
             ),
         )

backend/onyx/document_index/opensearch/search.py

@@ -734,14 +734,13 @@ def _get_hierarchy_node_filter(
             # document's metadata list.
             filter_clauses.append(_get_tag_filter(tags))
 
-        # Knowledge scope: explicit knowledge attachments restrict what
-        # an assistant can see.  When none are set the assistant
-        # searches everything.
+        # Knowledge scope: explicit knowledge attachments restrict what an
+        # assistant can see. When none are set the assistant searches
+        # everything.
         #
-        # project_id / persona_id are additive: they make overflowing
-        # user files findable but must NOT trigger the restriction on
-        # their own (an agent with no explicit knowledge should search
-        # everything).
+        # project_id / persona_id are additive: they make overflowing user files
+        # findable but must NOT trigger the restriction on their own (an agent
+        # with no explicit knowledge should search everything).
         has_knowledge_scope = (
             attached_document_ids
             or hierarchy_node_ids
@@ -769,9 +768,8 @@ def _get_hierarchy_node_filter(
                 knowledge_filter["bool"]["should"].append(
                     _get_document_set_filter(document_sets)
                 )
-            # Additive: widen scope to also cover overflowing user
-            # files, but only when an explicit restriction is already
-            # in effect.
+            # Additive: widen scope to also cover overflowing user files, but
+            # only when an explicit restriction is already in effect.
             if project_id is not None:
                 knowledge_filter["bool"]["should"].append(
                     _get_user_project_filter(project_id)

backend/onyx/document_index/vespa/index.py

@@ -690,9 +690,12 @@ def update_single(
             )
 
         project_ids: set[int] | None = None
+        # NOTE: Empty user_projects is semantically different from None
+        # user_projects.
         if user_fields is not None and user_fields.user_projects is not None:
             project_ids = set(user_fields.user_projects)
         persona_ids: set[int] | None = None
+        # NOTE: Empty personas is semantically different from None personas.
         if user_fields is not None and user_fields.personas is not None:
             persona_ids = set(user_fields.personas)
         update_request = MetadataUpdateRequest(