Standardize empty workspace handling from "_" to "" across storage

* Unify empty workspace behavior by changing workspace from "_" to ""
* Fixed incorrect empty workspace detection in get_all_update_flags_status()

lightrag/kg/faiss_impl.py

@@ -47,8 +47,8 @@ class FaissVectorDBStorage(BaseVectorStorage):
         else:
             # Default behavior when workspace is empty
             self.final_namespace = self.namespace
-            self.workspace = "_"
             workspace_dir = working_dir
+            self.workspace = ""
 
         os.makedirs(workspace_dir, exist_ok=True)
         self._faiss_index_file = os.path.join(

lightrag/kg/json_doc_status_impl.py

@@ -38,9 +38,9 @@ class JsonDocStatusStorage(DocStatusStorage):
             self.final_namespace = f"{self.workspace}_{self.namespace}"
         else:
             # Default behavior when workspace is empty
-            self.final_namespace = self.namespace
-            self.workspace = "_"
             workspace_dir = working_dir
+            self.final_namespace = self.namespace
+            self.workspace = ""
 
         os.makedirs(workspace_dir, exist_ok=True)
         self._file_name = os.path.join(workspace_dir, f"kv_store_{self.namespace}.json")

lightrag/kg/json_kv_impl.py

@@ -35,7 +35,7 @@ class JsonKVStorage(BaseKVStorage):
             # Default behavior when workspace is empty
             workspace_dir = working_dir
             self.final_namespace = self.namespace
-            self.workspace = "_"
+            self.workspace = ""
 
         os.makedirs(workspace_dir, exist_ok=True)
         self._file_name = os.path.join(workspace_dir, f"kv_store_{self.namespace}.json")

lightrag/kg/milvus_impl.py

@@ -961,8 +961,8 @@ class MilvusVectorDBStorage(BaseVectorStorage):
         else:
             # When workspace is empty, final_namespace equals original namespace
             self.final_namespace = self.namespace
+            self.workspace = ""
             logger.debug(f"Final namespace (no workspace): '{self.final_namespace}'")
-            self.workspace = "_"
 
         kwargs = self.global_config.get("vector_db_storage_cls_kwargs", {})
         cosine_threshold = kwargs.get("cosine_better_than_threshold")

lightrag/kg/mongo_impl.py

@@ -120,7 +120,7 @@ class MongoKVStorage(BaseKVStorage):
         else:
             # When workspace is empty, final_namespace equals original namespace
             self.final_namespace = self.namespace
-            self.workspace = "_"
+            self.workspace = ""
             logger.debug(
                 f"[{self.workspace}] Final namespace (no workspace): '{self.namespace}'"
             )
@@ -348,7 +348,7 @@ class MongoDocStatusStorage(DocStatusStorage):
         else:
             # When workspace is empty, final_namespace equals original namespace
             self.final_namespace = self.namespace
-            self.workspace = "_"
+            self.workspace = ""
             logger.debug(f"Final namespace (no workspace): '{self.final_namespace}'")
 
         self._collection_name = self.final_namespace
@@ -513,7 +513,7 @@ class MongoDocStatusStorage(DocStatusStorage):
             collation_config = {"locale": "zh", "numericOrdering": True}
 
             # Use workspace-specific index names to avoid cross-workspace conflicts
-            workspace_prefix = f"{self.workspace}_" if self.workspace != "_" else ""
+            workspace_prefix = f"{self.workspace}_" if self.workspace != "" else ""
 
             # 1. Define all indexes needed with workspace-specific names
             all_indexes = [
@@ -771,7 +771,7 @@ class MongoGraphStorage(BaseGraphStorage):
         else:
             # When workspace is empty, final_namespace equals original namespace
             self.final_namespace = self.namespace
-            self.workspace = "_"
+            self.workspace = ""
             logger.debug(f"Final namespace (no workspace): '{self.final_namespace}'")
 
         self._collection_name = self.final_namespace
@@ -2083,7 +2083,7 @@ class MongoVectorDBStorage(BaseVectorStorage):
         else:
             # When workspace is empty, final_namespace equals original namespace
             self.final_namespace = self.namespace
-            self.workspace = "_"
+            self.workspace = ""
             logger.debug(f"Final namespace (no workspace): '{self.final_namespace}'")
 
         # Set index name based on workspace for backward compatibility

lightrag/kg/nano_vector_db_impl.py

@@ -47,7 +47,7 @@ class NanoVectorDBStorage(BaseVectorStorage):
         else:
             # Default behavior when workspace is empty
             self.final_namespace = self.namespace
-            self.workspace = "_"
+            self.workspace = ""
             workspace_dir = working_dir
 
         os.makedirs(workspace_dir, exist_ok=True)

lightrag/kg/networkx_impl.py

@@ -46,7 +46,7 @@ class NetworkXStorage(BaseGraphStorage):
             # Default behavior when workspace is empty
             self.final_namespace = self.namespace
             workspace_dir = working_dir
-            self.workspace = "_"
+            self.workspace = ""
 
         os.makedirs(workspace_dir, exist_ok=True)
         self._graphml_xml_file = os.path.join(

lightrag/kg/redis_impl.py

@@ -153,7 +153,7 @@ class RedisKVStorage(BaseKVStorage):
         else:
             # When workspace is empty, final_namespace equals original namespace
             self.final_namespace = self.namespace
-            self.workspace = "_"
+            self.workspace = ""
             logger.debug(f"Final namespace (no workspace): '{self.final_namespace}'")
 
         self._redis_url = os.environ.get(