Re: Problem with __setattr__ and __getattribute__
Hi, I asked the same question earlier. When ID is set to None and object is saved, the M2M fields are not copied. They must be copied separately. Caveats: the code below uses django internals and is very lightly tested. def copy_m2m_fields(src, dst): for m2m_field in src._meta.many_to_many: attname = m2m_field.get_attname() src_manager = getattr(src, attname) # idea from django/core/serializers/python.py,base.py # ... collect primary keys ids = [related._get_pk_val() for related in src_manager.iterator()] # ... assign id list to target field setattr(dst, attname, ids) dst.save() Jacob Kaplan-Moss wrote: > Hi Dave -- > > I'm not sure what's going on in your code example, but there's a > *much* easier way of copying an object:: > > >>> o = MyModel.objects.get(pk=1) > >>> o.id = None > >>> o.save() > > By setting the ID (or whatever your primary key is called) to ``None`` > and calling save() you'll force Django to insert a new object instead > of updating the existing one. All that monkeying with ``__dict__`` > isn't really needed. > > /me makes note to think about adding an ``obj.copy()`` method... > > Jacob > > > > > --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to django-users@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/django-users?hl=en -~--~~~~--~~--~--~---
Re: Problem with __setattr__ and __getattribute__
Hi Dave -- I'm not sure what's going on in your code example, but there's a *much* easier way of copying an object:: >>> o = MyModel.objects.get(pk=1) >>> o.id = None >>> o.save() By setting the ID (or whatever your primary key is called) to ``None`` and calling save() you'll force Django to insert a new object instead of updating the existing one. All that monkeying with ``__dict__`` isn't really needed. /me makes note to think about adding an ``obj.copy()`` method... Jacob --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to django-users@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/django-users?hl=en -~--~~~~--~~--~--~---
Problem with __setattr__ and __getattribute__
Hello. I have a view that should duplicate a model object and save it in the database. I tried with this code: obj = MyModel.objects.get(pk=1) obj2 = MyModel() for e in obj.__dict__: if e != 'id': obj2.__setattr__(e, obj.__getattribute__(e)) #error obj2.save() But I get this error: Exception Type: TypeError Exception Value:expected 2 arguments, got 1 in the line marked with #error... The same code works if I execute it from the django shell... Why? By the way, is this a good way to duplicate an object or there are better methods? Thanks. --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to django-users@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/django-users?hl=en -~--~~~~--~~--~--~---
