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