Properly skip zmq tests without ZeroMQ being installed

In this change import_zmq() doesn't raise ImportError any more
for the benefit of skipping tests.
Alarm about zmq unavailability moved to driver's init.

Change-Id: I6e6acc39f42c979333510064d9e845228400d233
Closes-Bug: #1522920

oslo_messaging/_drivers/impl_zmq.py

@@ -26,7 +26,9 @@ from oslo_messaging._drivers import common as rpc_common
 from oslo_messaging._drivers.zmq_driver.client import zmq_client
 from oslo_messaging._drivers.zmq_driver.client import zmq_client_light
 from oslo_messaging._drivers.zmq_driver.server import zmq_server
+from oslo_messaging._drivers.zmq_driver import zmq_async
 from oslo_messaging._executors import impl_pooledexecutor  # FIXME(markmc)
+from oslo_messaging._i18n import _LE
 
 
 pformat = pprint.pformat
@@ -162,6 +164,10 @@ class ZmqDriver(base.BaseDriver):
         :param allowed_remote_exmods: remote exception passing options
         :type allowed_remote_exmods: list
         """
+        zmq = zmq_async.import_zmq()
+        if zmq is None:
+            raise ImportError(_LE("ZeroMQ is not available!"))
+
         conf.register_opts(zmq_opts)
         conf.register_opts(impl_pooledexecutor._pool_opts)
         conf.register_opts(base.base_opts)

oslo_messaging/_drivers/zmq_driver/zmq_async.py

@@ -30,12 +30,10 @@ def import_zmq(zmq_concurrency='eventlet'):
     _raise_error_if_invalid_config_value(zmq_concurrency)
 
     imported_zmq = importutils.try_import(ZMQ_MODULES[zmq_concurrency],
-                                          default='zmq')
+                                          default=None)
 
     if imported_zmq is None:
-        errmsg = _LE("ZeroMQ not found!")
         LOG.error(_LE("ZeroMQ not found!"))
-        raise ImportError(errmsg)
     return imported_zmq
 
 

oslo_messaging/tests/drivers/zmq/test_impl_zmq.py

@@ -224,6 +224,7 @@ class TestZmqBasics(ZmqBaseTestCase):
 
 class TestPoller(test_utils.BaseTestCase):
 
+    @testtools.skipIf(zmq is None, "zmq not available")
     def setUp(self):
         super(TestPoller, self).setUp()
         self.poller = zmq_async.get_poller()

oslo_messaging/tests/drivers/zmq/test_zmq_async.py

@@ -11,15 +11,19 @@
 #    under the License.
 
 import mock
+import testtools
 
 from oslo_messaging._drivers.zmq_driver.poller import green_poller
 from oslo_messaging._drivers.zmq_driver.poller import threading_poller
 from oslo_messaging._drivers.zmq_driver import zmq_async
 from oslo_messaging.tests import utils as test_utils
 
+zmq = zmq_async.import_zmq()
+
 
 class TestImportZmq(test_utils.BaseTestCase):
 
+    @testtools.skipIf(zmq is None, "zmq not available")
     def setUp(self):
         super(TestImportZmq, self).setUp()
 
@@ -29,12 +33,12 @@ class TestImportZmq(test_utils.BaseTestCase):
 
         zmq_async.importutils.try_import.return_value = 'mock zmq module'
         self.assertEqual('mock zmq module', zmq_async.import_zmq('native'))
-        mock_try_import.assert_called_with('zmq', default='zmq')
+        mock_try_import.assert_called_with('zmq', default=None)
 
         zmq_async.importutils.try_import.return_value = 'mock eventlet module'
         self.assertEqual('mock eventlet module',
                          zmq_async.import_zmq('eventlet'))
-        mock_try_import.assert_called_with('eventlet.green.zmq', default='zmq')
+        mock_try_import.assert_called_with('eventlet.green.zmq', default=None)
 
     def test_when_no_args_then_default_zmq_module_is_loaded(self):
         mock_try_import = mock.Mock()
@@ -42,14 +46,7 @@ class TestImportZmq(test_utils.BaseTestCase):
 
         zmq_async.import_zmq()
 
-        mock_try_import.assert_called_with('eventlet.green.zmq', default='zmq')
+        mock_try_import.assert_called_with('eventlet.green.zmq', default=None)
-
-    def test_when_import_fails_then_raise_ImportError(self):
-        zmq_async.importutils.try_import = mock.Mock()
-        zmq_async.importutils.try_import.return_value = None
-
-        with self.assertRaisesRegexp(ImportError, "ZeroMQ not found!"):
-            zmq_async.import_zmq('native')
 
     def test_invalid_config_value_raise_ValueError(self):
         invalid_opt = 'x'
@@ -61,6 +58,7 @@ class TestImportZmq(test_utils.BaseTestCase):
 
 class TestGetPoller(test_utils.BaseTestCase):
 
+    @testtools.skipIf(zmq is None, "zmq not available")
     def setUp(self):
         super(TestGetPoller, self).setUp()
 
@@ -100,6 +98,7 @@ class TestGetPoller(test_utils.BaseTestCase):
 
 class TestGetReplyPoller(test_utils.BaseTestCase):
 
+    @testtools.skipIf(zmq is None, "zmq not available")
     def setUp(self):
         super(TestGetReplyPoller, self).setUp()
 
@@ -134,6 +133,7 @@ class TestGetReplyPoller(test_utils.BaseTestCase):
 
 class TestGetExecutor(test_utils.BaseTestCase):
 
+    @testtools.skipIf(zmq is None, "zmq not available")
     def setUp(self):
         super(TestGetExecutor, self).setUp()