Move slug creation helper to main/utils

Signed-off-by: Dan McGee <dan@archlinux.org>

1 files changed, 15 insertions, 0 deletions

diff --git a/main/utils.py b/main/utils.py
index 17ca386e..cdd4ff71 100644
--- a/main/utils.py
+++ b/main/utils.py
@@ -9,6 +9,7 @@ import hashlib
 from django.core.cache import cache
 from django.db import connections, router
 from django.utils.timezone import now
+from django.template.defaultfilters import slugify
 
 
 CACHE_TIMEOUT = 1800
@@ -118,6 +119,20 @@ def set_created_field(sender, **kwargs):
         obj.last_modified = time
 
 
+def find_unique_slug(model, title):
+    '''Attempt to find a unique slug for this model with given title.'''
+    existing = set(model.objects.values_list(
+        'slug', flat=True).order_by().distinct())
+
+    suffixed = slug = slugify(title)
+    suffix = 0
+    while suffixed in existing:
+        suffix += 1
+        suffixed = "%s-%d" % (slug, suffix)
+
+    return suffixed
+
+
 def database_vendor(model, mode='read'):
     if mode == 'read':
         database = router.db_for_read(model)