Added more tests to increase coverage and fixed a couple bugs.

We can't inherit a class from a basestring and instantiate it, so I changed
the base class to 'object' so we can still to the type checking.

I also discovered a bug with the Django 1.3 compatibility work.  In the
incr_version method, we were using the Redis's rename function to move the key,
but in Redis 2.0 you cannot rename a volitile key.

Added some moar authors

AUTHORS.rst

@@ -2,5 +2,7 @@ Sean Bleier <http://github.com/sebleier>
 Matt Dennewitz <http://github.com/blackbrrr>
 Jannis Leidel <http://github.com/jezdez>
 S. Angel / Twidi <http://github.com/twidi>
+Noah Kantrowitz / coderanger <http://github.com/coderanger>
+Martin Mahner / bartTC <http://github.com/bartTC>
 
 Forked from http://github.com/sebleier/django-redis-cache

redis_cache/cache.py

@@ -14,11 +14,22 @@ except ImportError:
         "Redis cache backend requires the 'redis-py' library")
 
 
-class CacheKey(basestring):
+class CacheKey(object):
     """
     A stub string class that we can use to check if a key was created already.
     """
-    pass
+    def __init__(self, key):
+        self._key = key
+
+    def __eq__(self, other):
+        return self._key == other
+
+    def __str__(self):
+        return self.__unicode__()
+
+    def __unicode__(self):
+        return smart_str(self._key)
+
 
 class CacheClass(BaseCache):
     def __init__(self, server, params):
@@ -49,8 +60,8 @@ class CacheClass(BaseCache):
         Returns the utf-8 encoded bytestring of the given key as a CacheKey
         instance to be able to check if it was "made" before.
         """
-        if isinstance(key, CacheKey):
-            key = CacheKey(smart_str(key))
+        if not isinstance(key, CacheKey):
+            key = CacheKey(key)
         return key
 
     def add(self, key, value, timeout=None, version=None):
@@ -93,12 +104,13 @@ class CacheClass(BaseCache):
         Set content expiration, if necessary
         """
         key = self.make_key(key, version=version)
-        if timeout == 0:
+        if timeout is None:
+            timeout = self.default_timeout
+        if timeout <= 0:
             # force the key to be non-volatile
             result = self._cache.get(key)
             self._cache.set(key, result)
         else:
-            timeout = timeout or self.default_timeout
             # If the expiration command returns false, we need to reset the key
             # with the new expiration
             if not self._cache.expire(key, timeout):
@@ -130,9 +142,7 @@ class CacheClass(BaseCache):
         """
         Unpickles the given value.
         """
-        # pickle doesn't want a unicode!
         value = smart_str(value)
-        # hydrate that pickle
         return pickle.loads(value)
 
     def get_many(self, keys, version=None):
@@ -178,22 +188,30 @@ class RedisCache(CacheClass):
     """
     A subclass that is supposed to be used on Django >= 1.3.
     """
+
     def make_key(self, key, version=None):
         if not isinstance(key, CacheKey):
-            key = CacheKey(smart_str(super(CacheClass, self).make_key(key, version)))
+            key = CacheKey(super(CacheClass, self).make_key(key, version))
         return key
 
     def incr_version(self, key, delta=1, version=None):
         """
         Adds delta to the cache version for the supplied key. Returns the
         new version.
+
+        Note: In Redis 2.0 you cannot rename a volitle key, so we have to move
+        the value from the old key to the new key and maintain the ttl.
         """
         if version is None:
             version = self.version
-        key = self.make_key(key, version)
-        value = self.get(key, version=version)
+        old_key = self.make_key(key, version)
+        value = self.get(old_key, version=version)
+        ttl = self._cache.ttl(old_key)
         if value is None:
             raise ValueError("Key '%s' not found" % key)
-        incr_key = self.make_key(key, version=version+delta)
-        self._cache.rename(key, incr_key)
+        new_key = self.make_key(key, version=version+delta)
+        # TODO: See if we can check the version of Redis, since 2.2 will be able
+        # to rename volitile keys.
+        self.set(new_key, value, timeout=ttl)
+        self.delete(old_key)
         return version + delta

runtests.py

@@ -12,7 +12,17 @@ if not settings.configured:
         },
         INSTALLED_APPS = [
             'tests.testapp',
-        ]
+        ],
+        CACHES = {
+            'default': {
+                'BACKEND': 'redis_cache.RedisCache',
+                'LOCATION': '127.0.0.1:6379',
+                'OPTIONS': {
+                    'DB': 15,
+                    'PASSWORD': 'yadayada',
+                },
+            },
+        }
     )
 
 from django.test.simple import DjangoTestSuiteRunner

tests/settings.py

@@ -9,3 +9,14 @@ DATABASES = {
 INSTALLED_APPS = [
     'tests.testapp',
 ]
+
+CACHES = {
+    'default': {
+        'BACKEND': 'redis_cache.RedisCache',
+        'LOCATION': '127.0.0.1:6379',
+        'OPTIONS': { # optional
+            'DB': 15,
+            'PASSWORD': 'yadayada',
+        },
+    },
+}

tests/testapp/tests.py

@@ -7,9 +7,10 @@ try:
     import cPickle as pickle
 except ImportError:
     import pickle
-
+from django import VERSION
 from django.core.cache import get_cache
 from models import Poll, expensive_calculation
+from redis_cache.cache import RedisCache
 
 # functions/classes for complex data type tests
 def f():
@@ -25,10 +26,32 @@ class RedisCacheTests(unittest.TestCase):
     """
     def setUp(self):
         # use DB 16 for testing and hope there isn't any important data :->
-        self.cache = get_cache('redis_cache.cache://127.0.0.1:6379?db=15')
+        self.cache = self.get_cache()
 
     def tearDown(self):
         self.cache.clear()
+        self.cache.close()
+
+    def get_cache(self, backend=None):
+        if VERSION[0] == 1 and VERSION[1] < 3:
+            cache = get_cache(backend or 'redis_cache.cache://127.0.0.1:6379?db=15')
+        elif VERSION[0] == 1 and VERSION[1] >= 3:
+            cache = get_cache(backend or 'default')
+        return cache
+
+    def test_bad_db_initialization(self):
+        self.cache = self.get_cache('redis_cache.cache://127.0.0.1:6379?db=not_a_number')
+        self.assertEqual(self.cache._cache.db, 1)
+
+    def test_bad_port_initialization(self):
+        self.cache = self.get_cache('redis_cache.cache://127.0.0.1:not_a_number?db=15')
+        self.assertEqual(self.cache._cache.port, 6379)
+
+    def test_default_initialization(self):
+        self.cache = self.get_cache('redis_cache.cache://127.0.0.1')
+        self.assertEqual(self.cache._cache.host, '127.0.0.1')
+        self.assertEqual(self.cache._cache.db, 1)
+        self.assertEqual(self.cache._cache.port, 6379)
 
     def test_simple(self):
         # Simple cache set/get works
@@ -166,12 +189,12 @@ class RedisCacheTests(unittest.TestCase):
         self.assertEqual(self.cache.has_key("expire3"), False)
 
     def test_set_expiration_timeout_None(self):
-        key, value = 'key', 'value'
+        key, value = self.cache.make_key('key'), 'value'
         self.cache.set(key, value);
         self.assertTrue(self.cache._cache.ttl(key) > 0)
 
     def test_set_expiration_timeout_0(self):
-        key, value = 'key', 'value'
+        key, value = self.cache.make_key('key'), 'value'
         self.cache.set(key, value)
         self.assertTrue(self.cache._cache.ttl(key) > 0)
         self.cache.expire(key, 0)
@@ -268,5 +291,18 @@ class RedisCacheTests(unittest.TestCase):
         self.assertEqual(self.cache.get('key3'), 'sausage')
         self.assertEqual(self.cache.get('key4'), 'lobster bisque')
 
+    def test_incr_version(self):
+        if isinstance(self.cache, RedisCache):
+            old_key = "key1"
+            self.cache.set(old_key, "spam", version=1)
+            self.assertEqual(self.cache.make_key(old_key), ':1:key1')
+            new_version = self.cache.incr_version(old_key, 1)
+            self.assertEqual(new_version, 2)
+            new_key = self.cache.make_key(old_key, version=new_version)
+            self.assertEqual(new_key, ':2:key1')
+            self.assertEqual(self.cache.get(old_key), None)
+            self.assertEqual(self.cache.get(new_key), 'spam')
+
+
 if __name__ == '__main__':
     unittest.main()