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
def field_post_save(sender, **kwargs):
'''
A signal handler to run any post_save activities and trigger the built-in
post_save signals
1. Detect renamed fields and run migration
2. Create new fields, if necessary
2. Trigger post creation signal
3. Trigger post update signal
'''
MetaField=sender
meta_field=kwargs['instance']
try:
# Regenerate our MetaModel, which may have changed
DynamicModel = meta_field.meta_model.get_model()
# If we previously identified a renamed field name, then rename the column
if hasattr(meta_field, '_old_name'):
utils.rename_db_column(DynamicModel, meta_field._old_name, meta_field.name)
del meta_field._old_name
# If necessary, add any new columns
utils.add_necessary_db_columns(DynamicModel)
# Check if the field has just been created
if hasattr(meta_field, '_creation'):
post_field_creation.send(sender=DynamicModel,new_field=meta_field)
del meta_field._creation
# Check if the field has just been updated
if hasattr(meta_field, '_update'):
post_field_update.send(sender=DynamicModel,old_field=meta_field._update,new_field=meta_field)
del meta_field._update
except ObjectDoesNotExist:
return
