Added Application HolidayViewer

src/core/settings_management.py

@@ -1,8 +1,8 @@
 import logging
 from datetime import datetime
 
+from constants import NOT_LOGGED, NO_SESSION
 from core.dbengine import DbEngine, TAG_PARENT, TAG_USER, TAG_DATE, DbException
-from core.instance_manager import NO_SESSION, NOT_LOGGED
 from core.settings_objects import *
 
 load_settings_obj()  # needed to make sure that the import of core is not removed
@@ -13,6 +13,10 @@ logger = logging.getLogger(__name__)
 
 
 class NoDefaultCls:
+  """
+  No Default value class
+  Return when no default value is provided.
+  """
   pass
 
 
@@ -155,6 +159,14 @@ class SettingsTransaction:
 
 
 class GenericDbManager:
+  """
+  Given an obj_entry (entry in DbEngine) and obj_type (object to serialize),
+  >>> db = GenericDbManager(session, settings_manager, obj_entry, obj_type)
+  >>> db.prop_name = value # will save the value to the database.
+  >>> db.prop_name # will load the value from the database.
+
+  """
+  
   def __init__(self, session, settings_manager: SettingsManager, obj_entry, obj_type):
     self.__dict__["_session"] = session
     self.__dict__["_settings_manager"] = settings_manager
@@ -167,7 +179,7 @@ class GenericDbManager:
     
     settings = self._settings_manager.load(self._session, self._obj_entry, self._obj_type())
     if not (hasattr(settings, key)):
-      raise AttributeError(f"Settings {self._obj_entry.__name__} has no attribute {key}")
+      raise AttributeError(f"Settings '{self._obj_entry}' has no attribute '{key}'.")
     
     setattr(settings, key, value)
     self._settings_manager.save(self._session, self._obj_entry, settings)
@@ -178,6 +190,68 @@ class GenericDbManager:
     
     settings = self._settings_manager.load(self._session, self._obj_entry, self._obj_type())
     if not (hasattr(settings, item)):
-      raise AttributeError(f"Settings {self._obj_entry.__name__} has no attribute {item}")
+      raise AttributeError(f"Settings '{self._obj_entry}' has no attribute '{item}'.")
     
     return getattr(settings, item)
+
+
+class NestedSettingsManager:
+  """
+  Manages access and modification of a specific subset of persistent settings.
+
+  The GenericSubDbManager class provides mechanisms to dynamically get and set 
+  attributes for a specified settings object accessed through a session. It 
+  handles the retrieval, modification, and persistence of settings using a 
+  settings manager, ensuring that only valid attributes can be managed.
+
+  Given an obj_entry (entry in DbEngine) and obj_type (object to serialize),
+  >>> db = NestedSettingsManager(session, settings_manager, obj_entry, obj_type, obj_attribute)
+  >>> db.prop_name = value # will save obj_type.obj_attribute.prop_name in database
+  >>> db.prop_name # will load obj_type.obj_attribute.prop_name from database
+  """
+  
+  def __init__(self, session: dict, settings_manager: SettingsManager, obj_entry, obj_type, obj_attribute):
+    self.__dict__["_session"] = session
+    self.__dict__["_settings_manager"] = settings_manager
+    self.__dict__["_obj_entry"] = obj_entry
+    self.__dict__["_obj_type"] = obj_type
+    self.__dict__["_obj_attribute"] = obj_attribute
+  
+  def __getattr__(self, item):
+    if item.startswith("_"):
+      return super().__getattribute__(item)
+    
+    settings, obj = self._get_settings_and_object()
+    
+    if not hasattr(obj, item):
+      raise AttributeError(f"Settings '{self._obj_attribute}' has no attribute '{item}'.")
+    
+    return getattr(obj, item)
+  
+  def __setattr__(self, key, value):
+    if key.startswith("_"):
+      super().__setattr__(key, value)
+    
+    settings, obj = self._get_settings_and_object()
+    if not (hasattr(obj, key)):
+      raise AttributeError(f"Settings '{self._obj_attribute}', from '{self._obj_entry}' has no attribute '{key}'.")
+    
+    setattr(obj, key, value)
+    self._settings_manager.save(self._session, self._obj_entry, settings)
+  
+  def update(self, values: dict, ignore_missing=False):
+    settings, obj = self._get_settings_and_object()
+    for k, v in values.items():
+      if hasattr(obj, k):
+        setattr(obj, k, v)
+      elif not ignore_missing:
+        raise AttributeError(f"Settings '{self._obj_attribute}', from '{self._obj_entry}' has no attribute '{k}'.")
+    
+    self._settings_manager.save(self._session, self._obj_entry, settings)
+  
+  def _get_settings_and_object(self):
+    settings = self._settings_manager.load(self._session, self._obj_entry, self._obj_type())
+    if not hasattr(settings, self._obj_attribute):
+      raise AttributeError(f"Settings '{self._obj_entry}' has no attribute '{self._obj_attribute}'.")
+    
+    return settings, getattr(settings, self._obj_attribute)