planetstack/model_policy.py

   1 from django.db.models.signals import post_save
   2 from django.dispatch import receiver
   3 import pdb
   4 from core.models import *
   5 from dependency_walker import *
   6 import model_policies
   7
   8 def update_dep(d, o):
   9         if (d.updated < o.updated):
  10                 d.save(update_fields=['updated'])
  11
  12 def delete_if_inactive(d, o):
  13         #print "Deleting %s (%s)"%(d,d.__class__.__name__)
  14         d.delete()
  15         return
  16
  17 @receiver(post_save)
  18 def post_save_handler(sender, instance, **kwargs):
  19         sender_name = sender.__name__
  20         policy_name = 'model_policy_%s'%sender_name
  21
  22         if (not kwargs['update_fields']):
  23                 # Automatic dirtying
  24                 walk_inv_deps(update_dep, instance)
  25
  26                 try:
  27                         policy_handler = getattr(model_policies, policy_name, None)
  28                         if policy_handler is not None:
  29                                 policy_handler.handle(instance)
  30
  31
  32                 except:
  33                         pass
  34         elif 'deleted' in kwargs['update_fields']:
  35                 walk_inv_deps(delete_if_inactive, instance)
  36