Merge pull request #68 from tiqi-group/fix/only_load_state_properties_can_be_updated

fix: only load state properties can be updated

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "pydase"
-version = "0.3.0"
+version = "0.3.1"
 description = "A flexible and robust Python library for creating, managing, and interacting with data services, with built-in support for web and RPC servers, and customizable features for diverse use cases."
 authors = ["Mose Mueller <mosmuell@ethz.ch>"]
 readme = "README.md"

src/pydase/data_service/state_manager.py

@@ -148,7 +148,10 @@ class StateManager:
             value, value_type = nested_json_dict["value"], nested_json_dict["type"]
             class_attr_value_type = nested_class_dict.get("type", None)
 
-            if class_attr_value_type == value_type:
+            if (
+                class_attr_value_type == value_type
+                and self.__is_loadable_state_attribute(path)
+            ):
                 self.set_service_attribute_value_by_path(path, value)
             else:
                 logger.info(
@@ -231,21 +234,36 @@ class StateManager:
         # Traverse the object according to the path parts
         target_obj = get_object_attr_from_path_list(self.service, parent_path_list)
 
-        if self.__attr_value_should_change(target_obj, attr_name):
+        if attr_cache_type in ("ColouredEnum", "Enum"):
-            if attr_cache_type in ("ColouredEnum", "Enum"):
+            enum_attr = get_object_attr_from_path_list(target_obj, [attr_name])
-                enum_attr = get_object_attr_from_path_list(target_obj, [attr_name])
+            setattr(target_obj, attr_name, enum_attr.__class__[value])
-                setattr(target_obj, attr_name, enum_attr.__class__[value])
+        elif attr_cache_type == "list":
-            elif attr_cache_type == "list":
+            list_obj = get_object_attr_from_path_list(target_obj, [attr_name])
-                list_obj = get_object_attr_from_path_list(target_obj, [attr_name])
+            list_obj[index] = value
-                list_obj[index] = value
+        else:
-            else:
+            setattr(target_obj, attr_name, value)
-                setattr(target_obj, attr_name, value)
+
+    def __is_loadable_state_attribute(self, property_path: str) -> bool:
+        """Checks if an attribute defined by a dot-separated path should be loaded from
+        storage.
+
+        For properties, it verifies the presence of the '@load_state' decorator. Regular
+        attributes default to being loadable.
+        """
+
+        parent_object = get_object_attr_from_path_list(
+            self.service, property_path.split(".")[:-1]
+        )
+        attr_name = property_path.split(".")[-1]
 
-    def __attr_value_should_change(self, parent_object: Any, attr_name: str) -> bool:
-        # If the attribute is a property, change it using the setter without getting
-        # the property value (would otherwise be bad for expensive getter methods)
         prop = getattr(type(parent_object), attr_name, None)
 
         if isinstance(prop, property):
-            return has_load_state_decorator(prop)
+            has_decorator = has_load_state_decorator(prop)
+            if not has_decorator:
+                logger.debug(
+                    f"Property {attr_name!r} has no '@load_state' decorator. "
+                    "Ignoring value from JSON file..."
+                )
+            return has_decorator
         return True

tests/data_service/test_state_manager.py

@@ -153,7 +153,10 @@ def test_load_state(tmp_path: Path, caplog: LogCaptureFixture):
     assert service.subservice.name == "SubService"  # didn't change
 
     assert "Service.some_unit changed to 12.0 A!" in caplog.text
-    assert "Attribute 'name' is read-only. Ignoring new value..." in caplog.text
+    assert (
+        "Property 'name' has no '@load_state' decorator. "
+        "Ignoring value from JSON file..." in caplog.text
+    )
     assert (
         "Attribute type of 'some_float' changed from 'int' to 'float'. "
         "Ignoring value from JSON file..."
@@ -195,7 +198,11 @@ def test_readonly_attribute(tmp_path: Path, caplog: LogCaptureFixture):
     service = Service()
     manager = StateManager(service=service, filename=str(file))
     manager.load_state()
-    assert "Attribute 'name' is read-only. Ignoring new value..." in caplog.text
+    assert service.name == "Service"
+    assert (
+        "Property 'name' has no '@load_state' decorator. "
+        "Ignoring value from JSON file..." in caplog.text
+    )
 
 
 def test_changed_type(tmp_path: Path, caplog: LogCaptureFixture):