planetstack/core/models/plcorebase.py

   1 import os
   2 from django.db import models
   3 from django.forms.models import model_to_dict
   4
   5 class PlCoreBase(models.Model):
   6
   7     created = models.DateTimeField(auto_now_add=True)
   8     updated = models.DateTimeField(auto_now=True)
   9
  10     class Meta:
  11         abstract = True
  12         app_label = "core"
  13
  14     def __init__(self, *args, **kwargs):
  15         super(PlCoreBase, self).__init__(*args, **kwargs)
  16         self.__initial = self._dict
  17
  18     @property
  19     def diff(self):
  20         d1 = self.__initial
  21         d2 = self._dict
  22         diffs = [(k, (v, d2[k])) for k, v in d1.items() if v != d2[k]]
  23         return dict(diffs)
  24
  25     @property
  26     def has_changed(self):
  27         return bool(self.diff)
  28
  29     @property
  30     def changed_fields(self):
  31         return self.diff.keys()
  32
  33     def get_field_diff(self, field_name):
  34         return self.diff.get(field_name, None)
  35
  36     def save(self, *args, **kwargs):
  37         super(PlCoreBase, self).save(*args, **kwargs)
  38         self.__initial = self._dict
  39
  40     @property
  41     def _dict(self):
  42         return model_to_dict(self, fields=[field.name for field in
  43                              self._meta.fields])
  44
  45
  46