Return empty dict from get_many()

- Return an empty dict from django_redis.cache.RedisCache.get_many() when
  IGNORE_EXCEPTIONS is True.
- Convert omit_exception decorator to a callable. Pass it a return_value
  keyword argument to specify a default return value when
  IGNORE_EXCEPTIONS is True.

django_redis/cache.py

@@ -16,26 +16,25 @@
     logger = logging.getLogger((DJANGO_REDIS_LOGGER or __name__))
 
 
-def omit_exception(method):
+def omit_exception(method=None, return_value=None):
     """
     Simple decorator that intercepts connection
     errors and ignores these if settings specify this.
-
-    Note: this doesn't handle the `default` argument in .get().
     """
 
+    if method is None:
+        return functools.partial(omit_exception, return_value=return_value)
+
     @functools.wraps(method)
     def _decorator(self, *args, **kwargs):
         try:
             return method(self, *args, **kwargs)
         except ConnectionInterrupted as e:
             if self._ignore_exceptions:
-
                 if DJANGO_REDIS_LOG_IGNORED_EXCEPTIONS:
                     logger.error(str(e))
 
-                return None
-
+                return return_value
             raise e.parent
 
     return _decorator
@@ -79,7 +78,7 @@ def add(self, *args, **kwargs):
     def get(self, key, default=None, version=None, client=None):
         try:
             return self.client.get(key, default=default, version=version,
-                               client=client)
+                                   client=client)
         except ConnectionInterrupted:
             if self._ignore_exceptions:
                 if DJANGO_REDIS_LOG_IGNORED_EXCEPTIONS:
@@ -103,7 +102,7 @@ def delete_many(self, *args, **kwargs):
     def clear(self):
         return self.client.clear()
 
-    @omit_exception
+    @omit_exception(return_value={})
     def get_many(self, *args, **kwargs):
         return self.client.get_many(*args, **kwargs)
 

tests/redis_backend_testapp/tests.py

@@ -547,9 +547,15 @@ def setUp(self):
         self._orig_setting = django_redis.cache.DJANGO_REDIS_IGNORE_EXCEPTIONS
         django_redis.cache.DJANGO_REDIS_IGNORE_EXCEPTIONS = True
         self.cache = get_cache("doesnotexist")
+        self.cache._orig_ignore_exceptions = self.cache._ignore_exceptions
+        self.cache._ignore_exceptions = True
 
     def tearDown(self):
         django_redis.cache.DJANGO_REDIS_IGNORE_EXCEPTIONS = self._orig_setting
+        self.cache._ignore_exceptions = self.cache._orig_ignore_exceptions
+
+    def test_get_many_returns_default_arg(self):
+        self.assertEqual(self.cache.get_many(["key1", "key2", "key3"]), {})
 
     def test_get(self):
         self.assertIsNone(self.cache.get("key"))