From 04cb9d727764da3c0d3ba30783ba25dc828e3899 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Marek=20St=C4=99pniowski?= <marek@stepniowski.com>
Date: Tue, 16 Sep 2008 10:32:34 +0200
Subject: [PATCH 1/1] Generating random hash for each created shelf.

---
 apps/catalogue/forms.py |  3 ++-
 apps/catalogue/utils.py | 21 +++++++++++++++++++++
 2 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/apps/catalogue/forms.py b/apps/catalogue/forms.py
index 6506deb45..688e5edd0 100644
--- a/apps/catalogue/forms.py
+++ b/apps/catalogue/forms.py
@@ -4,6 +4,7 @@ from slughifi import slughifi
 
 from catalogue.models import Tag
 from catalogue.fields import JQueryAutoCompleteField
+from catalogue import utils
 
 
 class SearchForm(forms.Form):
@@ -46,7 +47,7 @@ class NewSetForm(forms.Form):
         
     def save(self, user, commit=True):
         name = self.cleaned_data['name']
-        new_set = Tag(name=name, slug=slughifi(name), sort_key=slughifi(name),
+        new_set = Tag(name=name, slug=utils.get_random_hash(name), sort_key=slughifi(name),
             category='set', user=user)
         
         new_set.save()
diff --git a/apps/catalogue/utils.py b/apps/catalogue/utils.py
index d1cee5045..72b097392 100644
--- a/apps/catalogue/utils.py
+++ b/apps/catalogue/utils.py
@@ -1,4 +1,25 @@
 # -*- coding: utf-8 -*-
+import random
+import time
+from base64 import urlsafe_b64encode
+
+from django.utils.hashcompat import sha_constructor
+from django.conf import settings
+
+
+# Use the system (hardware-based) random number generator if it exists.
+if hasattr(random, 'SystemRandom'):
+    randrange = random.SystemRandom().randrange
+else:
+    randrange = random.randrange
+MAX_SESSION_KEY = 18446744073709551616L     # 2 << 63
+
+
+def get_random_hash(seed):
+    sha_digest = sha_constructor('%s%s%s%s' % 
+        (randrange(0, MAX_SESSION_KEY), time.time(), unicode(seed).encode('utf-8', 'replace'),
+        settings.SECRET_KEY)).digest()
+    return urlsafe_b64encode(sha_digest).replace('=', '').replace('_', '-').lower()
 
 
 def split_tags(tags):
-- 
2.20.1