forum/models/tag.py

   1 import datetime
   2 from base import *
   3
   4 from django.utils.translation import ugettext as _
   5 from django.utils.encoding import smart_unicode, force_unicode
   6
   7 from forum import modules
   8
   9 class ActiveTagManager(CachedManager):
  10     use_for_related_fields = True
  11
  12     def get_query_set(self):
  13         return super(ActiveTagManager, self).get_query_set().exclude(used_count__lt=1)
  14
  15 class Tag(BaseModel):
  16     name            = models.CharField(max_length=255, unique=True)
  17     created_by      = models.ForeignKey(User, related_name='created_tags')
  18     created_at      = models.DateTimeField(default=datetime.datetime.now, blank=True, null=True)
  19     marked_by       = models.ManyToManyField(User, related_name="marked_tags", through="MarkedTag")
  20     # Denormalised data
  21     used_count = models.PositiveIntegerField(default=0)
  22
  23     active = ActiveTagManager()
  24
  25     class Meta:
  26         ordering = ('-used_count', 'name')
  27         app_label = 'forum'
  28
  29     def __unicode__(self):
  30         return force_unicode(self.name)
  31
  32     def add_to_usage_count(self, value):
  33         if self.used_count + value < 0:
  34             self.used_count = 0
  35         else:
  36             self.used_count = models.F('used_count') + value
  37
  38     def cache_key(self):
  39         return self._generate_cache_key(Tag.safe_cache_name(self.name))
  40
  41     @classmethod
  42     def safe_cache_name(cls, name):
  43         return "".join([str(ord(c)) for c in name])
  44
  45     @classmethod
  46     def infer_cache_key(cls, querydict):
  47         if 'name' in querydict:
  48             return cls._generate_cache_key(cls.safe_cache_name(querydict['name']))
  49
  50         return None
  51
  52     @classmethod
  53     def value_to_list_on_cache_query(cls):
  54         return 'name'
  55
  56     @models.permalink
  57     def get_absolute_url(self):
  58         return ('tag_questions', (), {'tag': self.name})
  59
  60 class MarkedTag(models.Model):
  61     TAG_MARK_REASONS = (('good', _('interesting')), ('bad', _('ignored')))
  62     tag = models.ForeignKey(Tag, related_name='user_selections')
  63     user = models.ForeignKey(User, related_name='tag_selections')
  64     reason = models.CharField(max_length=16, choices=TAG_MARK_REASONS)
  65
  66     class Meta:
  67         app_label = 'forum'
  68