From 56ec7d20f19b698d106f519c174089caceebb5dc Mon Sep 17 00:00:00 2001
From: microbluey <microbluey@gmail.com>
Date: Thu, 23 Jul 2026 22:11:09 +0800
Subject: [PATCH] fix(vector_stores/opensearch): translate the '*' wildcard to
 an exists query for every key (#6522)

---
 mem0/vector_stores/opensearch.py       | 12 ++++++--
 tests/vector_stores/test_opensearch.py | 40 ++++++++++++++++++++++++--
 2 files changed, 48 insertions(+), 4 deletions(-)

diff --git a/mem0/vector_stores/opensearch.py b/mem0/vector_stores/opensearch.py
index ad06a2419..d041e9a65 100644
--- a/mem0/vector_stores/opensearch.py
+++ b/mem0/vector_stores/opensearch.py
@@ -35,8 +35,16 @@ def _build_filter_clauses(filters):
     for key, value in (filters or {}).items():
         if value is None:
             continue
-        if key not in _IDENTITY_FILTER_KEYS and (not isinstance(value, (str, int, float, bool)) or value == "*"):
-            logger.debug(f"Ignoring non-scalar or wildcard filter value for key {key!r}")
+        if value == "*":
+            # "Any value" wildcard (a documented Platform pattern): match
+            # documents where the field exists — as opensearch.ts already
+            # does for every key — instead of a literal, near-always-empty
+            # term match on the string "*".
+            _validate_filter(key, value)
+            filter_clauses.append({"exists": {"field": f"payload.{key}"}})
+            continue
+        if key not in _IDENTITY_FILTER_KEYS and not isinstance(value, (str, int, float, bool)):
+            logger.debug(f"Ignoring non-scalar filter value for key {key!r}")
             continue
         _validate_filter(key, value)
         field = f"payload.{key}.keyword" if isinstance(value, str) else f"payload.{key}"
diff --git a/tests/vector_stores/test_opensearch.py b/tests/vector_stores/test_opensearch.py
index 3b93aadbd..ae413cf44 100644
--- a/tests/vector_stores/test_opensearch.py
+++ b/tests/vector_stores/test_opensearch.py
@@ -643,13 +643,49 @@ class TestOpenSearchCustomFilters(TestOpenSearchFilterValidation):
         clauses = self._search_body()["query"]["bool"]["filter"]
         self.assertEqual(clauses, [{"term": {"payload.user_id.keyword": "alice"}}])
 
-    def test_search_ignores_wildcard_filter_value(self):
+    def test_search_translates_wildcard_filter_value_to_exists(self):
         self.os_db.search(query="", vectors=[[0.1] * 1536], filters={"user_id": "alice", "category": "*"})
         clauses = self._search_body()["query"]["bool"]["filter"]
-        self.assertEqual(clauses, [{"term": {"payload.user_id.keyword": "alice"}}])
+        self.assertEqual(
+            clauses,
+            [
+                {"term": {"payload.user_id.keyword": "alice"}},
+                {"exists": {"field": "payload.category"}},
+            ],
+        )
 
     def test_list_ignores_or_operator_filter(self):
         self.os_db.list(filters={"user_id": "alice", "$or": [{"a": 1}]})
         self.client_mock.search.assert_called_once()
         clauses = self._search_body()["query"]["bool"]["filter"]
         self.assertEqual(clauses, [{"term": {"payload.user_id.keyword": "alice"}}])
+
+
+class TestOpenSearchWildcardFilters(TestOpenSearchFilterValidation):
+    """The "*" wildcard means "any value" (a documented Platform pattern) and
+    must build an exists query — as opensearch.ts does — for every key,
+    including the identity keys, instead of a literal term match on "*"."""
+
+    def setUp(self):
+        super().setUp()
+        self.client_mock.search.return_value = {"hits": {"hits": []}}
+
+    def _search_body(self):
+        return self.client_mock.search.call_args[1]["body"]
+
+    def test_identity_key_wildcard_builds_exists_query(self):
+        self.os_db.search(query="", vectors=[[0.1] * 1536], filters={"agent_id": "*"})
+        clauses = self._search_body()["query"]["bool"]["filter"]
+        self.assertIn({"exists": {"field": "payload.agent_id"}}, clauses)
+        self.assertNotIn({"term": {"payload.agent_id.keyword": "*"}}, clauses)
+
+    def test_custom_key_wildcard_builds_exists_query(self):
+        self.os_db.list(filters={"category": "*"})
+        clauses = self._search_body()["query"]["bool"]["filter"]
+        self.assertIn({"exists": {"field": "payload.category"}}, clauses)
+
+    def test_wildcard_combines_with_term_filters(self):
+        self.os_db.keyword_search(query="q", filters={"user_id": "u1", "topic": "*"})
+        clauses = self._search_body()["query"]["bool"]["filter"]
+        self.assertIn({"term": {"payload.user_id.keyword": "u1"}}, clauses)
+        self.assertIn({"exists": {"field": "payload.topic"}}, clauses)