mygpo/votes/models.py

   1 from django.db import models
   2 from django.conf import settings
   3 from django.contrib.contenttypes.models import ContentType
   4 from django.contrib.contenttypes import generic
   5 from django.contrib.contenttypes.fields import GenericRelation
   6
   7 from uuidfield import UUIDField
   8
   9 from mygpo.core.models import UpdateInfoModel
  10
  11
  12 class Vote(UpdateInfoModel):
  13     """ A vote by a user for some object """
  14
  15     # the user who voted
  16     user = models.ForeignKey(settings.AUTH_USER_MODEL,
  17                              on_delete=models.CASCADE)
  18
  19     # the object that was voted for
  20     content_type = models.ForeignKey(ContentType, on_delete=models.PROTECT)
  21     # this should suit UUID and integer primary keys
  22     object_id = UUIDField()
  23     content_object = generic.GenericForeignKey('content_type', 'object_id')
  24
  25     class Meta:
  26         unique_together = [
  27             # a user can only vote once per object
  28             ('user', 'content_type', 'object_id'),
  29         ]
  30
  31
  32 class VoteMixin(models.Model):
  33
  34     votes = GenericRelation('Vote', related_query_name='votes')
  35
  36     class Meta:
  37         abstract = True
  38
  39     def vote(self, user):
  40         """ Register a vote from the user for the current object """
  41         Vote.objects.get_or_create(
  42             user=user,
  43             content_type=ContentType.objects.get_for_model(self),
  44             object_id=obj.pk,
  45         )
  46
  47     def vote_count(self):
  48         return self.votes.count()