Add disabled_drivers config option

The new config option 'disabled_drivers' is designed to address a
typical user case: As cloud provider, I'd like to only provide
some particular drivers, e.g. fedora atomic/k8s and don't expose
any other driver support. With this patch, when user create a new
template which is in 'disabled_drivers'. A BadRequest error will
be returned.

Closes-Bug: #1746961

Change-Id: Ib4c53ffed78a1847b2da9672e6348c88757ad66e

magnum/api/controllers/v1/cluster_template.py

@@ -368,6 +368,7 @@ class ClusterTemplatesController(base.Controller):
     @validation.enforce_network_driver_types_create()
     @validation.enforce_volume_driver_types_create()
     @validation.enforce_volume_storage_size_create()
+    @validation.enforce_driver_supported()
     def post(self, cluster_template):
         """Create a new ClusterTemplate.
 

magnum/api/validation.py

@@ -48,6 +48,30 @@ def enforce_cluster_type_supported():
     return wrapper
 
 
+def enforce_driver_supported():
+    @decorator.decorator
+    def wrapper(func, *args, **kwargs):
+        cluster_template = args[1]
+        cluster_distro = cluster_template.cluster_distro
+        if not cluster_distro:
+            try:
+                cli = clients.OpenStackClients(pecan.request.context)
+                image_id = cluster_template.image_id
+                image = api_utils.get_openstack_resource(cli.glance().images,
+                                                         image_id,
+                                                         'images')
+                cluster_distro = image.get('os_distro')
+            except Exception:
+                pass
+        cluster_type = (cluster_template.server_type,
+                        cluster_distro,
+                        cluster_template.coe)
+        driver.Driver.get_driver(*cluster_type)
+        return func(*args, **kwargs)
+
+    return wrapper
+
+
 def enforce_cluster_volume_storage_size():
     @decorator.decorator
     def wrapper(func, *args, **kwargs):

magnum/conf/drivers.py

@@ -33,7 +33,13 @@ drivers_opts = [
     cfg.BoolOpt('send_cluster_metrics',
                 default=True,
                 help='Allow periodic tasks to pull COE data and send to '
-                     'ceilometer.')
+                     'ceilometer.'),
+    cfg.ListOpt('disabled_drivers',
+                default=[],
+                help='Disabled driver entry points. The default value is []. '
+                     ' Means if not specified, then all available drivers '
+                     'are enabled.'
+                ),
 ]
 
 

magnum/drivers/common/driver.py

@@ -34,7 +34,8 @@ class Driver(object):
     @classmethod
     def load_entry_points(cls):
         for entry_point in iter_entry_points('magnum.drivers'):
-            yield entry_point, entry_point.load(require=False)
+            if entry_point.name not in CONF.drivers.disabled_drivers:
+                yield entry_point, entry_point.load(require=False)
 
     @classmethod
     def get_drivers(cls):

magnum/tests/unit/api/controllers/v1/test_cluster_template.py

@@ -1017,6 +1017,14 @@ class TestPost(api_base.FunctionalTest):
             self.assertEqual(201, resp.status_int)
             self.assertIsNotNone(resp.json['name'])
 
+    def test_create_cluster_with_disabled_driver(self):
+        cfg.CONF.set_override('disabled_drivers',
+                              ['mesos_ubuntu_v1'],
+                              group='drivers')
+        bdict = apiutils.cluster_template_post_data(coe="mesos")
+        self.assertRaises(AppError, self.post_json, '/clustertemplates',
+                          bdict)
+
 
 class TestDelete(api_base.FunctionalTest):