Removes state manager from all service instances that have no filename set or are not exposed

src/pydase/data_service/abstract_data_service.py

@@ -14,6 +14,6 @@ class AbstractDataService(ABC):
     __root__: DataService
     _task_manager: TaskManager
     _callback_manager: CallbackManager
-    _state_manager: StateManager
+    _state_manager: Optional[StateManager]
     _autostart_tasks: dict[str, tuple[Any]]
     _filename: Optional[str]

src/pydase/data_service/data_service.py

@@ -43,7 +43,7 @@ class DataService(rpyc.Service, AbstractDataService):
         self._filename: Optional[str] = filename
         self._callback_manager: CallbackManager = CallbackManager(self)
         self._task_manager = TaskManager(self)
-        self._state_manager = StateManager(self)
+        self._state_manager: Optional[StateManager] = None
 
         if not hasattr(self, "_autostart_tasks"):
             self._autostart_tasks = {}
@@ -56,7 +56,9 @@ class DataService(rpyc.Service, AbstractDataService):
         self.__check_instance_classes()
         self._initialised = True
 
-        self._state_manager.load_state()
+        if self._filename is not None:
+            self._state_manager = StateManager(self)
+            self._state_manager.load_state()
 
     def __setattr__(self, __name: str, __value: Any) -> None:
         # converting attributes that are not properties

src/pydase/server/server.py

@@ -17,6 +17,7 @@ from uvicorn.server import HANDLED_SIGNALS
 
 import pydase.units as u
 from pydase import DataService
+from pydase.data_service.state_manager import StateManager
 from pydase.version import __version__
 
 from .web_server import WebAPI
@@ -163,6 +164,9 @@ class Server:
         **kwargs: Any,
     ) -> None:
         self._service = service
+        if self._service._state_manager is None:
+            self._service._state_manager = StateManager(self._service)
+            self._service._state_manager.load_state()
         self._host = host
         self._rpc_port = rpc_port
         self._web_port = web_port

src/pydase/server/web_server.py

@@ -114,13 +114,17 @@ class WebAPI:
 
         @app.get("/service-properties")
         def service_properties() -> dict[str, Any]:
-            return self.service._state_manager.cache
+            if self.service._state_manager is not None:
+                return self.service._state_manager.cache
+            else:
+                logger.error("Exposed service does not have a state manager.")
+                return {}
 
         # exposing custom.css file provided by user
         if self.css is not None:
 
             @app.get("/custom.css")
-            async def styles():
+            async def styles() -> FileResponse:
                 return FileResponse(str(self.css))
 
         app.mount(