def change_class(self, obj, newclass, **kw):
"""
Change the class of the object.
This process will actually instantiate a new object of ``newclass`` and
copy the state from ``obj`` to the new object. Finally, the new object
will replace ``obj`` in the database.
:param obj: The object whose class to change.
:param newclass: The new parent class of the object.
:param kw: The keyword arguments to pass the the new object init.
"""
invoke_hook(obj, "before_class_changed", newclass=newclass, **kw)
obj = obj._real_object()
newobj = newclass(**kw)
newobj.__dict__.update(obj.__dict__)
if isinstance(obj, PersistentSlots):
slots = set()
for c in obj.__class__.__mro__:
if '__slots__' in c.__dict__:
slots.update(c.__slots__)
for slot in slots:
if slot in obj.__dict__:
continue
try:
slot_val = getattr(obj, slot)
setattr(newobj, slot, slot_val)
except AttributeError:
continue
self.unregister_object(obj)
self.register_object(newobj, force_id=obj.obj_id)
invoke_hook(newobj, "after_class_changed", oldclass=obj.__class__, **kw)
return newobj.ref()
def on_server_shutdown(self):
"""
Run just prior to server shutdown.
"""
for obj in self.objects.itervalues():
invoke_hook(obj, 'server_shutdown')
for task in self.tasks.itervalues():
task.server_shutdown()
def on_server_startup(self):
"""
Run once per server start after everything is loaded and ready.
"""
for task in self.tasks.itervalues():
task.server_startup()
for obj in self.objects.itervalues():
invoke_hook(obj, 'server_startup')
def create(cls, **kwargs):
"""
Create an instance of the class and register it with the database.
@param cls: The class to instantiate.
@param kwargs: Any initialization arguments to pass to the class.
@return: A reference to the new object.
"""
if cls.db is None:
raise Exception("Database not available to %s" % cls.__name__)
obj = cls(**kwargs)
cls.db.register_object(obj)
invoke_hook(obj, 'after_created')
return obj.ref()
def delete(self):
"""
Canonical method for deleting an object.
"""
invoke_hook(self, 'before_deleted')
self.db.unregister_object(self)
