Fix user_id functionality (#2548)

mem0/memory/setup.py

@@ -3,6 +3,7 @@ import os
 import uuid
 
 # Set up the directory path
+VECTOR_ID = str(uuid.uuid4())
 home_dir = os.path.expanduser("~")
 mem0_dir = os.environ.get("MEM0_DIR") or os.path.join(home_dir, ".mem0")
 os.makedirs(mem0_dir, exist_ok=True)
@@ -29,3 +30,27 @@ def get_user_id():
             return user_id
     except Exception:
         return "anonymous_user"
+
+
+def get_or_create_user_id(vector_store):
+    """Store user_id in vector store and return it."""
+    user_id = get_user_id()
+
+    # Try to get existing user_id from vector store
+    try:
+        existing = vector_store.get(vector_id=VECTOR_ID)
+        if existing and hasattr(existing, "payload") and existing.payload and "user_id" in existing.payload:
+            return existing.payload["user_id"]
+    except:
+        pass
+
+    # If we get here, we need to insert the user_id
+    try:
+        dims = getattr(vector_store, "embedding_model_dims", 1)
+        vector_store.insert(
+            vectors=[[0.0] * dims], payloads=[{"user_id": user_id, "type": "user_identity"}], ids=[VECTOR_ID]
+        )
+    except:
+        pass
+
+    return user_id