Merge pull request #2 from udacity/update_django

[osqa.git] / forum / models / tag.py

diff --git a/forum/models/tag.py b/forum/models/tag.py
index d189a1ce83bfb20851659e7963a832dfcb5127d7..eca23e468ae8d186605b5989831191284a8fed77 100644 (file)
--- a/forum/models/tag.py
+++ b/forum/models/tag.py
@@ -1,14 +1,18 @@
 import datetime
 from base import *
 
-from forum.modules import MODULES_PACKAGE
-
+from django.conf import settings as django_settings
+from django.core.cache.backends.base import BaseCache
 from django.utils.translation import ugettext as _
-import django.dispatch
+from django.utils.encoding import smart_unicode, force_unicode
+
+from forum import modules
+
+class ActiveTagManager(CachedManager):
+    use_for_related_fields = True
 
-class ActiveTagManager(models.Manager):
-    def get_query_set(self):
-        return super(ActiveTagManager, self).get_query_set().exclude(used_count__lt=1)
+    def get_queryset(self):
+        return super(ActiveTagManager, self).get_queryset().exclude(used_count__lt=1)
 
 class Tag(BaseModel):
     name            = models.CharField(max_length=255, unique=True)
@@ -19,14 +23,13 @@ class Tag(BaseModel):
     used_count = models.PositiveIntegerField(default=0)
 
     active = ActiveTagManager()
-    objects = ActiveTagManager()
 
     class Meta:
         ordering = ('-used_count', 'name')
         app_label = 'forum'
 
     def __unicode__(self):
-        return u'%s' % self.name
+        return force_unicode(self.name)
 
     def add_to_usage_count(self, value):
         if self.used_count + value < 0:
@@ -34,6 +37,29 @@ class Tag(BaseModel):
         else:
             self.used_count = models.F('used_count') + value
 
+    def cache_key(self):
+        return self._generate_cache_key(Tag.safe_cache_name(self.name))
+
+    @classmethod
+    def safe_cache_name(cls, name):
+        return "".join([str(ord(c)) for c in name])
+
+    @classmethod
+    def infer_cache_key(cls, querydict):
+        if 'name' in querydict:
+            cache_key = cls._generate_cache_key(cls.safe_cache_name(querydict['name']))
+
+            if len(cache_key) > django_settings.CACHE_MAX_KEY_LENGTH:
+                cache_key = cache_key[:django_settings.CACHE_MAX_KEY_LENGTH]
+
+            return cache_key
+
+        return None
+
+    @classmethod
+    def value_to_list_on_cache_query(cls):
+        return 'name'
+
     @models.permalink
     def get_absolute_url(self):
         return ('tag_questions', (), {'tag': self.name})