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     enacted = models.DateTimeField(null=True, default=None)
  10
  11     class Meta:
  12         abstract = True
  13         app_label = "core"
  14
  15     def __init__(self, *args, **kwargs):
  16         super(PlCoreBase, self).__init__(*args, **kwargs)
  17         self.__initial = self._dict
  18
  19     @property
  20     def diff(self):
  21         d1 = self.__initial
  22         d2 = self._dict
  23         diffs = [(k, (v, d2[k])) for k, v in d1.items() if v != d2[k]]
  24         return dict(diffs)
  25
  26     @property
  27     def has_changed(self):
  28         return bool(self.diff)
  29
  30     @property
  31     def changed_fields(self):
  32         return self.diff.keys()
  33
  34     def get_field_diff(self, field_name):
  35         return self.diff.get(field_name, None)
  36
  37     def save(self, *args, **kwargs):
  38         super(PlCoreBase, self).save(*args, **kwargs)
  39         self.__initial = self._dict
  40
  41     @property
  42     def _dict(self):
  43         return model_to_dict(self, fields=[field.name for field in
  44                              self._meta.fields])
  45
  46
  47