merged in session cache separation

courseware/content_parser.py

@@ -11,10 +11,11 @@ from lxml import etree
 
 try: # This lets us do __name__ == ='__main__'
     from django.conf import settings
-    from django.core.cache import cache
+
     from student.models import UserProfile
     from student.models import UserTestGroup
     from mitxmako.shortcuts import render_to_response, render_to_string
+    from util.cache import cache
 except: 
     settings = None 
 
@@ -157,10 +158,7 @@ def user_groups(user):
     cache_expiration = 60 * 60 # one hour
     
     # Kill caching on dev machines -- we switch groups a lot
-    if "dev" not in settings.DEFAULT_GROUPS:
-        group_names = cache.get(fasthash(key))
-    else: 
-        group_names = None
+    group_names = cache.get(fasthash(key))
  
     if group_names is None:
         group_names = [u.name for u in UserTestGroup.objects.filter(users=user)]

settings.py

@@ -163,6 +163,13 @@ MAKO_TEMPLATES = {}
 
 LOGGING_ENV = "dev" # override this in different environments
 
+# Default dev cache (i.e. no caching)
+CACHES = {
+    'default': {
+        'BACKEND': 'django.core.cache.backends.dummy.DummyCache',
+    }
+}
+
 # Make sure we execute correctly regardless of where we're called from
 execfile(os.path.join(BASE_DIR, "settings.py"))
 

simplewiki/models.py

@@ -3,7 +3,6 @@ import os
 
 from django import forms
 from django.contrib.auth.models import User
-from django.core.cache import cache
 from django.core.urlresolvers import reverse
 from django.db import models
 from django.db.models import signals
@@ -11,6 +10,8 @@ from django.utils.translation import ugettext_lazy as _
 from markdown import markdown
 
 from settings import *
+from util.cache import cache
+
 
 class ShouldHaveExactlyOneRootSlug(Exception):
     pass

util/cache.py

@@ -0,0 +1,16 @@
+"""
+This module aims to give a little more fine-tuned control of caching and cache
+invalidation. Import these instead of django.core.cache.
+
+Note that 'default' is being preserved for user session caching, which we're 
+not migrating so as not to inconvenience users by logging them all out.
+"""
+from django.core import cache
+
+# If we can't find a 'general' CACHE defined in settings.py, we simply fall back
+# to returning the default cache. This will happen with dev machines.
+try:
+    cache = cache.get_cache('general')
+except ValueError:
+    cache = cache.cache
+