Add a test for re-caching a token

There was no test that showed that when a token was in the cache
and a request is made to validate it again, it gets cached again.

Change-Id: I1992fa6b5ddc0792dfd1ce90fb888c365ecb1612
Partial-Bug: #1289075

keystonemiddleware/tests/test_auth_token_middleware.py

@@ -1212,6 +1212,38 @@ class CommonAuthTokenMiddlewareTest(object):
                                       use_kerberos=use_kerberos,
                                       success=False)
 
+    def test_caching_token_on_verify(self):
+        # When the token is cached, it's cached again when it's verified.
+        # NOTE(blk-u): This behavior is incorrect and inefficient, see
+        # bug 1289075.
+
+        # The token cache has to be initialized with our cache instance.
+        self.middleware._token_cache._env_cache_name = 'cache'
+        cache = memorycache.Client()
+        self.middleware._token_cache.initialize(env={'cache': cache})
+
+        # Mock cache.set since then the test can verify call_count.
+        orig_cache_set = cache.set
+        cache.set = mock.Mock(side_effect=orig_cache_set)
+
+        token = self.token_dict['signed_token_scoped']
+
+        req = webob.Request.blank('/')
+        req.headers['X-Auth-Token'] = token
+        self.middleware(req.environ, self.start_fake_response)
+        self.assertEqual(200, self.response_status)
+
+        self.assertThat(1, matchers.Equals(cache.set.call_count))
+
+        req = webob.Request.blank('/')
+        req.headers['X-Auth-Token'] = token
+        self.middleware(req.environ, self.start_fake_response)
+        self.assertEqual(200, self.response_status)
+
+        # FIXME(blk-u): This should be 1 since the token shouldn't be cached
+        # again.
+        self.assertThat(2, matchers.Equals(cache.set.call_count))
+
 
 class V2CertDownloadMiddlewareTest(BaseAuthTokenMiddlewareTest,
                                    testresources.ResourcedTestCase):