Merge "Fix formatting of ImportError"

keystone/common/manager.py

@@ -78,7 +78,7 @@ def load_driver(namespace, driver_name, *args):
         return driver_manager.driver
     except stevedore.exception.NoMatches:
         msg = (_('Unable to find %(name)r driver in %(namespace)r.'))
-        raise ImportError(msg, {'name': driver_name, 'namespace': namespace})
+        raise ImportError(msg % {'name': driver_name, 'namespace': namespace})
 
 
 class _TraceMeta(type):

keystone/tests/unit/token/test_common.py

@@ -10,9 +10,12 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
+import uuid
+
 from six.moves import urllib
 
 from keystone.tests import unit
+from keystone.token import provider
 from keystone.token.providers import common
 
 
@@ -20,3 +23,14 @@ class TestTokenProvidersCommon(unit.TestCase):
     def test_strings_are_url_safe(self):
         s = common.random_urlsafe_str()
         self.assertEqual(s, urllib.parse.quote_plus(s))
+
+    def test_unsupported_provider_raises_import_error(self):
+        namespace = "keystone.token.provider"
+        # Generate a random name
+        driver = uuid.uuid4().hex
+        self.config_fixture.config(group='token', provider=driver)
+        msg = "Unable to find '%(driver)s' driver in '%(namespace)s'." % {
+            'namespace': namespace, 'driver': driver
+        }
+
+        self.assertRaisesRegex(ImportError, msg, provider.Manager)

releasenotes/notes/bug-1753584-e052bc7805f001b4.yaml

@@ -0,0 +1,6 @@
+---
+fixes:
+  - |
+    [`bug 1753584 <https://bugs.launchpad.net/keystone/+bug/1753584>`_]
+    Fix formatting of ImportError when using a driver not found in the list
+    of token providers.