Commit 8e838d9c authored by Emre Yilmaz's avatar Emre Yilmaz Committed by Tim Graham
Browse files

Fixed #25840 -- Fixed BaseCache.get_or_set() on the DummyCache backend. 

This also fixes a possible data eviction race condition between
setting and getting a key. Another thread could remove the key
before get_and_set() accesses it again. In this case, now the
default value will be returned instead of None.
parent 25f5b5c1

django/core/cache/backends/base.py

+1 −1
Original line number Diff line number Diff line
@@ -165,7 +165,7 @@ class BaseCache(object): 
                default = default()

            val = self.add(key, default, timeout=timeout, version=version)

            if val:

                return self.get(key, version=version)

                return self.get(key, default, version)

        return val



    def has_key(self, key, version=None):

docs/releases/1.9.1.txt

+2 −1
Original line number Diff line number Diff line
@@ -9,4 +9,5 @@ Django 1.9.1 fixes several bugs in 1.9. 
Bugfixes

========



* ...
 
* Fixed ``BaseCache.get_or_set()`` with the ``DummyCache`` backend

  (:ticket:`25840`).

tests/cache/tests.py

+9 −0
Original line number Diff line number Diff line
@@ -202,6 +202,15 @@ class DummyCacheTests(SimpleTestCase): 
        self.assertRaises(ValueError, cache.decr_version, 'answer')

        self.assertRaises(ValueError, cache.decr_version, 'does_not_exist')



    def test_get_or_set(self):

        self.assertEqual(cache.get_or_set('mykey', 'default'), 'default')



    def test_get_or_set_callable(self):

        def my_callable():

            return 'default'



        self.assertEqual(cache.get_or_set('mykey', my_callable), 'default')





def custom_key_func(key, key_prefix, version):

    "A customized cache key function"