def get_model(self,*args,**kwargs):
'''
Returns a functional Django model based on current data
Attention: this method does not take are of the model cache, admin, DB etc,
this needs to be done separately.
'''
#if hasattr(self,'_model'):
# return self._model
# Get all associated fields into a list ready for dict()
#fields = [(f.name, f.get_django_field()) for f in self._fields.all()]
# Use the create_model function defined above
#self._model= model_factory(self)
# Do not return anything, if model is not saved yet
if not self.id:
return None
_app_label = getattr(self,'app',None).lower() or DYNAMO_DEFAULT_APP.lower()
_model_name = self.name.encode('ascii')
try:
# try to get the model from the model cache
m=app_cache.app_models[_app_label][_model_name]
except KeyError:
# Model has never been created before, just continue with the process
pass
except:
# Any other error should be raised
raise
else:
# if model was found, check the hash to identify changes
if m.hash==self.get_hash():
# return cached model, since nothing has changed
return m
else:
# we need to clear the model cache here, otherwise
# the metaclass ModelBase will not generate it, but get
# the old one from the cache, when we run the type(...) statement
remove_from_model_cache(_app_label,_model_name)
# Create the model from sratch
class Meta:
app_label = _app_label
verbose_name = self.verbose_name
unique_together=self.unique_together
attrs=self.django_fields
attrs.update({
'Meta': Meta,
'__module__': getattr(self,'module',DYNAMO_DEFAULT_MODULE),
'__unicode__': lambda s: '%s' % self.name,
'hash': self.get_hash(),
'admin': self.admin
})
return type(_model_name, (models.Model,), attrs)
def field_post_delete(sender, **kwargs):
'''
A signal handler to run any pre_save activities and trigger the built-in
pre_save signals
1. Update the database with regard to the deleted field
2. Trigger the post delete signal
'''
MetaField=sender
meta_field=kwargs['instance']
try:
# Regenerate our MetaModel, which may have changed
DynamicModel = meta_field.meta_model.get_model(regenerate=True, notify_changes=True)
utils.unregister_in_admin(admin_site, DynamicModel)
utils.remove_from_model_cache(DynamicModel._meta.app_label, DynamicModel.__name__)
# Delete field in the database
if DYNAMO_DELETE_FIELDS:
# TODO: no delete field function available yet
pass
post_field_update.send(sender=Dynamic_model,field=meta_field)
except:
pass
