Nova: Refactor utils._boot_servers to generate its own name prefix

Previously, _boot_servers() required a server name prefix; it now
generates its own if one is not provided, moving name generation into
the utility instead of needing to put it in the scenario.

Change-Id: Ie3b6a8ff06d7f05e15fdff4e338c3705f6d0124a

rally/plugins/openstack/scenarios/glance/images.py

@@ -115,6 +115,4 @@ class GlanceImages(utils.GlanceScenario, nova_utils.NovaScenario):
                                    image_location,
                                    disk_format)
         image_id = image.id
-        server_name = self._generate_random_name(prefix="rally_novaserver_")
+        self._boot_servers(image_id, flavor, number_instances, **kwargs)
-        self._boot_servers(server_name, image_id,
-                           flavor, number_instances, **kwargs)

rally/plugins/openstack/scenarios/nova/utils.py

@@ -459,22 +459,24 @@ class NovaScenario(base.Scenario):
         self.clients("nova").keypairs.delete(keypair_name)
 
     @base.atomic_action_timer("nova.boot_servers")
-    def _boot_servers(self, name_prefix, image_id, flavor_id,
+    def _boot_servers(self, image_id, flavor_id, requests, name_prefix=None,
-                      requests, instances_amount=1, **kwargs):
+                      instances_amount=1, **kwargs):
         """Boot multiple servers.
 
         Returns when all the servers are actually booted and are in the
         "Active" state.
 
-        :param name_prefix: The prefix to use while naming the created servers.
-                            The rest of the server names will be '_No.'
         :param image_id: ID of the image to be used for server creation
         :param flavor_id: ID of the flavor to be used for server creation
         :param requests: Number of booting requests to perform
+        :param name_prefix: The prefix to use while naming the created servers.
+                            The rest of the server names will be '_<number>'
         :param instances_amount: Number of instances to boot per each request
 
         :returns: List of created server objects
         """
+        if not name_prefix:
+            name_prefix = self._generate_random_name()
         for i in range(requests):
             self.clients("nova").servers.create("%s_%d" % (name_prefix, i),
                                                 image_id, flavor_id,

tests/unit/plugins/openstack/scenarios/glance/test_images.py

@@ -62,15 +62,13 @@ class GlanceImagesTestCase(test.TestCase):
                                             "url", "df", fakearg="f")
         mock_delete.assert_called_once_with(fake_image)
 
-    @mock.patch(GLANCE_IMAGES + "._generate_random_name")
     @mock.patch(GLANCE_IMAGES + "._boot_servers")
     @mock.patch(GLANCE_IMAGES + "._create_image")
     @mock.patch("rally.benchmark.runners.base.osclients")
     def test_create_image_and_boot_instances(self,
                                              mock_osclients,
                                              mock_create_image,
-                                             mock_boot_servers,
+                                             mock_boot_servers):
-                                             mock_random_name):
         glance_scenario = images.GlanceImages()
         nova_scenario = servers.NovaServers()
         fc = fakes.FakeClients()
@@ -85,7 +83,6 @@ class GlanceImagesTestCase(test.TestCase):
         fake_servers = [object() for i in range(5)]
         mock_create_image.return_value = fake_image
         mock_boot_servers.return_value = fake_servers
-        mock_random_name.return_value = "random_name"
         kwargs = {"fakearg": "f"}
         with mock.patch("rally.plugins.openstack.scenarios."
                         "glance.utils.time.sleep"):
@@ -94,6 +91,5 @@ class GlanceImagesTestCase(test.TestCase):
                                                             5, **kwargs)
             mock_create_image.assert_called_once_with("cf",
                                                       "url", "df")
-            mock_boot_servers.assert_called_once_with("random_name",
+            mock_boot_servers.assert_called_once_with("image-id-0",
-                                                      "image-id-0",
                                                       "fid", 5, **kwargs)

tests/unit/plugins/openstack/scenarios/nova/test_utils.py

@@ -433,7 +433,7 @@ class NovaScenarioTestCase(test.TestCase):
         mock_clients("nova").servers.list.return_value = [self.server,
                                                           self.server1]
         nova_scenario = utils.NovaScenario()
-        nova_scenario._boot_servers("prefix", "image", "flavor", 2)
+        nova_scenario._boot_servers("image", "flavor", 2)
         expected = [
             mock.call(
                 self.server, is_ready=self.res_is.mock(),