--- a/src/ldt/ldt/ldt_utils/models.py	Tue Dec 13 14:46:29 2011 +0100
+++ b/src/ldt/ldt/ldt_utils/models.py	Tue Dec 13 15:46:34 2011 +0100
@@ -321,7 +321,7 @@
                 everyone = Group.objects.get(name=settings.PUBLIC_GROUP_NAME)
                 if value:
                     assign('view_content', everyone, self) 
-                    assign('view_media', everyone, self)               
+                    assign('view_media', everyone, self.media_obj)               
                 else:
                     remove_perm('view_content', everyone, self)
                     remove_perm('vew_media', everyone, self.media_obj)

--- a/src/ldt/ldt/ldt_utils/views.py	Tue Dec 13 14:46:29 2011 +0100
+++ b/src/ldt/ldt/ldt_utils/views.py	Tue Dec 13 15:46:34 2011 +0100
@@ -24,7 +24,7 @@
 from ldt.ldt_utils.utils import boolean_convert, LdtUtils, LdtSearch
 from ldt.security.utils import (assign_perm_to_obj, set_forbidden_stream, 
     add_change_attr, get_userlist, get_userlist_model, get_userlist_group)
-from ldt.security.cache import get_checker_for, assign
+from ldt.security.cache import get_cached_checker, cached_assign
 from lxml.html import fragment_fromstring
 from models import Media, Project
 from projectserializer import ProjectSerializer
@@ -67,7 +67,7 @@
 
     # get list of all published projects
     group_list = request.user.groups.exclude(name=settings.PUBLIC_GROUP_NAME)
-    checker = get_checker_for(request.user)
+    checker = get_cached_checker(request.user)
     
     group_list = sorted(group_list.all(), key=lambda group: group.name.lower())
     
@@ -228,7 +228,7 @@
         
     group_list = group_list.exclude(name=settings.PUBLIC_GROUP_NAME)
     group_list = sorted(group_list.all(), key=lambda group: group.name.lower())
-    checker = get_checker_for(request.user)
+    checker = get_cached_checker(request.user)
     for g in group_list:
         if checker.has_perm('change_group', g):
             g.change = True
@@ -1082,7 +1082,7 @@
                         mimetype = mimetypes.guess_type(cleaned_data['src'])
                     cleaned_data['mimetype_field'] = mimetype
                     media, created = Media.safe_objects.get_or_create(src=cleaned_data['src'], defaults=cleaned_data) #@UndefinedVariable
-                    assign('view_media', request.user, media)
+                    cached_assign('view_media', request.user, media)
                 else:
                     media = None
                     
@@ -1094,8 +1094,8 @@
                 if not mimetype:
                     mimetype = mimetypes.guess_type(media.src)
                 media.mimetype_field = mimetype
-                assign('view_media', request.user, media)
-                assign('change_media', request.user, media)
+                cached_assign('view_media', request.user, media)
+                cached_assign('change_media', request.user, media)
                 media.save()                 
             
             if form_status != "error": 
@@ -1108,14 +1108,14 @@
                      
                 content, created = Content.safe_objects.get_or_create(iri_id=content_form.cleaned_data['iri_id'], defaults=content_defaults) #@UndefinedVariable
                 
-                assign('change_content', request.user, content)
-                assign('view_content', request.user, content)
+                cached_assign('change_content', request.user, content)
+                cached_assign('view_content', request.user, content)
                 everyone = Group.objects.get(name=settings.PUBLIC_GROUP_NAME)
                         
                 if content_form.cleaned_data['is_public']:
-                    assign('view_content', everyone, content)
+                    cached_assign('view_content', everyone, content)
                     if media:
-                        assign('view_media', everyone, media)
+                        cached_assign('view_media', everyone, media)
                 else:
                     remove_perm('view_content', everyone, content)
                     assign_perm_to_obj(content, content_form.cleaned_data['read_list'], content_form.cleaned_data['write_list'], request.user)
@@ -1292,15 +1292,15 @@
             
             group = Group.objects.create(name=name)
             group.save()
-            assign('is_owner_group', request.user, group)
-            assign('change_group', request.user, group)
+            cached_assign('is_owner_group', request.user, group)
+            cached_assign('change_group', request.user, group)
             request.user.groups.add(group)             
 
             for elem in members_list:
                 if hasattr(elem, 'username'):
                     elem.groups.add(group)
                     if elem in admin_list:
-                        assign('change_group', elem, group)
+                        cached_assign('change_group', elem, group)
                         
             form_status = 'saved'
             
@@ -1312,7 +1312,7 @@
 @login_required
 def update_group(request, group_id):
     group = get_object_or_404(Group, id=group_id)
-    checker = get_checker_for(request.user)
+    checker = get_cached_checker(request.user)
     
     if not checker.has_perm('change_group', group):
         form_status = 'none'
@@ -1344,7 +1344,7 @@
                         group.user_set.add(user)
                         if is_owner_group:
                             if user in admin_list:
-                                assign('change_group', user, group)
+                                cached_assign('change_group', user, group)
                             else:
                                 remove_perm('change_group', user, group)
                                 

--- a/src/ldt/ldt/security/cache.py	Tue Dec 13 14:46:29 2011 +0100
+++ b/src/ldt/ldt/security/cache.py	Tue Dec 13 15:46:34 2011 +0100
@@ -1,8 +1,11 @@
 from django.core.cache import cache
+from django.conf import settings
 from guardian.core import ObjectPermissionChecker
+from django.contrib.auth.models import User
+from django.db.models import Q
 from guardian.shortcuts import assign
 
-def get_checker_for(user):
+def get_cached_checker(user):
     key_name = 'checker_%s' % user.username
     
     checker = cache.get(key_name)
@@ -14,12 +17,23 @@
     return checker
 
 
-def assign(perm, user_or_group, object):
+def cached_assign(perm, user_or_group, object):
     assign(perm, user_or_group, object)
     
-    if hasattr('username', user_or_group):
+    if hasattr(user_or_group, 'username'):
         key = 'checker_%s' % user_or_group.username
     else:
         key = 'checker_%s' % user_or_group.name
         
-    cache.delete('checker_%s' % key)
\ No newline at end of file
+    cache.delete('checker_%s' % key)
+    
+    
+def get_cached_userlist():
+    userlist = cache.get('userlist')
+    if userlist:
+        return userlist
+    
+    query = Q(id=settings.ANONYMOUS_USER_ID) | Q(is_superuser=True)
+    userlist = User.objects.exclude(query)
+    cache.set('userlist', userlist)
+    return userlist
\ No newline at end of file

--- a/src/ldt/ldt/security/utils.py	Tue Dec 13 14:46:29 2011 +0100
+++ b/src/ldt/ldt/security/utils.py	Tue Dec 13 15:46:34 2011 +0100
@@ -1,9 +1,7 @@
 from django.conf import settings
 from django.contrib.contenttypes.models import ContentType
-from django.contrib.auth.models import User
-from django.db.models import Q
 from guardian.shortcuts import assign, remove_perm, get_users_with_perms, get_groups_with_perms
-from cache import get_checker_for
+from cache import get_cached_checker, get_cached_userlist
 
 try:
     from threading import local
@@ -26,8 +24,7 @@
     if cls_list:
         user = get_current_user()
         for cls in ToProtect.get_models():
-                protect_model(cls, user)
-    
+                protect_model(cls, user)    
     
 def unprotect_models():
     for cls in ToProtect.get_models():
@@ -105,7 +102,7 @@
     cls = ctype.model_class()
     
     if model_name in [cls_name.lower() for cls_name in settings.USE_GROUP_PERMISSIONS]:
-        checker = get_checker_for(user)
+        checker = get_cached_checker(user)
     else:
         checker = None
         
@@ -142,8 +139,7 @@
     remove_perms(read_list, old_groups, object, name) 
     
 def get_userlist(user, filter=None):
-    query = Q(id=settings.ANONYMOUS_USER_ID) | Q(id=user.id) | Q(is_superuser=True)
-    user_list = User.objects.exclude(query)
+    user_list = get_cached_userlist().exclude(id=user.id)
     if filter:
         user_list = user_list.filter(username__icontains=filter)
     elem_list = [{'name': u.username, 'id': u.id, 'type': 'user'} for u in user_list[0:settings.MAX_USERS_SEARCH]]

--- a/src/ldt/ldt/static/ldt/css/ldtform.css	Tue Dec 13 14:46:29 2011 +0100
+++ b/src/ldt/ldt/static/ldt/css/ldtform.css	Tue Dec 13 15:46:34 2011 +0100
@@ -138,7 +138,7 @@
 }
 
 #ldtcreatecontentstablediv {
-	max-height: 280px;
+	max-height: 230px;
 }
 
 #ldtcreatecontentslistcontainer {