Merge "[zmq] Added a processing to handle ImportError in Redis plugin of Matchmaker"

oslo_messaging/_drivers/zmq_driver/matchmaker/zmq_matchmaker_redis.py

@@ -19,7 +19,7 @@ from oslo_utils import importutils
 
 from oslo_messaging._drivers.zmq_driver.matchmaker import zmq_matchmaker_base
 from oslo_messaging._drivers.zmq_driver import zmq_address
-from oslo_messaging._i18n import _LW
+from oslo_messaging._i18n import _LW, _LE
 
 redis = importutils.try_import('redis')
 redis_sentinel = importutils.try_import('redis.sentinel')
@@ -112,6 +112,8 @@ class MatchmakerRedis(zmq_matchmaker_base.MatchmakerBase):
     def __init__(self, conf, *args, **kwargs):
         super(MatchmakerRedis, self).__init__(conf, *args, **kwargs)
         self.conf.register_opts(matchmaker_redis_opts, "matchmaker_redis")
+        if redis is None:
+            raise ImportError(_LE("Redis package is not available!"))
 
         self.sentinel_hosts = self._extract_sentinel_options()
         if not self.sentinel_hosts:

oslo_messaging/tests/drivers/zmq/matchmaker/test_impl_matchmaker.py

@@ -13,6 +13,7 @@
 #    under the License.
 
 from fixtures._fixtures import timeout
+import inspect
 import retrying
 from stevedore import driver
 import testscenarios
@@ -100,3 +101,17 @@ class TestImplMatchmaker(test_utils.BaseTestCase):
         except (timeout.TimeoutException, retrying.RetryError):
             pass
         self.assertEqual([], hosts)
+
+    def test_handle_redis_package_error(self):
+        if self.rpc_zmq_matchmaker == "redis":
+            # move 'redis' variable to prevent this case affect others
+            module = inspect.getmodule(self.test_matcher)
+            redis_package = module.redis
+
+            # 'redis' variable is set None, when importing package is failed
+            module.redis = None
+            self.assertRaises(ImportError, self.test_matcher.__init__,
+                              self.conf)
+
+            # retrieve 'redis' variable wihch is set originally
+            module.redis = redis_package