Add nova.ListAndGetHosts scenario

List all nova hosts,and get detailed information
Measure the "nova host-describe" command performance.

Change-Id: I10d4b9a4f118f671c6eb91a67b178ecdf08b8a54

rally-jobs/nova.yaml

@@ -1171,6 +1171,21 @@
         failure_rate:
           max: 0
 
+  NovaHosts.list_and_get_hosts:
+    -
+      args: {}
+      runner:
+        type: "constant"
+        concurrency: 2
+        times: 5
+      context:
+        users:
+          tenants: 3
+          users_per_tenant: 2
+      sla:
+        failure_rate:
+          max: 0
+
   NovaServices.list_services:
     -
       runner:

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

@@ -16,6 +16,7 @@
 from rally import consts
 from rally.plugins.openstack import scenario
 from rally.plugins.openstack.scenarios.nova import utils
+from rally.task import atomic
 from rally.task import validation
 
 
@@ -37,3 +38,23 @@ class ListHosts(utils.NovaScenario):
                      availability-zones
         """
         self._list_hosts(zone)
+
+
+@validation.required_services(consts.Service.NOVA)
+@validation.required_openstack(admin=True)
+@scenario.configure(name="NovaHosts.list_and_get_hosts")
+class ListAndGetHosts(utils.NovaScenario):
+
+    def run(self, zone=None):
+        """List all nova hosts,and get detailed information fot this hosts.
+
+        Measure the "nova host-describe" command performance.
+
+        :param zone: List nova hosts in an availability-zone.
+                     None (default value) means list hosts in all
+                     availability-zones
+        """
+        hosts = self._list_hosts(zone)
+        with atomic.ActionTimer(self, "nova.get_%s_hosts" % len(hosts)):
+            for host in hosts:
+                self._get_host(host.host_name, atomic_action=False)

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

@@ -1013,6 +1013,18 @@ class NovaScenario(scenario.OpenStackScenario):
         """
         return self.admin_clients("nova").hosts.list(zone)
 
+    @atomic.optional_action_timer("nova.get_host")
+    def _get_host(self, host_name):
+        """Describe a specific host.
+
+        :param host_name: host name to get.
+        :param atomic_action: True if this is atomic action. added and
+                              handled by the optional_action_timer()
+                              decorator.
+        :returns: host object
+        """
+        return self.admin_clients("nova").hosts.get(host_name)
+
     @atomic.action_timer("nova.list_services")
     def _list_services(self, host=None, binary=None):
         """return all nova service details

samples/tasks/scenarios/nova/list-and-get-hosts.json

@@ -0,0 +1,23 @@
+{
+  "NovaHosts.list_and_get_hosts": [
+    {
+      "args": {},
+      "runner": {
+        "type": "constant",
+        "concurrency": 2,
+        "times": 10
+      },
+      "context": {
+        "users": {
+          "tenants": 2,
+          "users_per_tenant": 2
+        }
+      },
+      "sla": {
+        "failure_rate": {
+          "max": 0
+        }
+      }
+    }
+  ]
+}

samples/tasks/scenarios/nova/list-and-get-hosts.yaml

@@ -0,0 +1,15 @@
+---
+  NovaHosts.list_and_get_hosts:
+    -
+      args: {}
+      runner:
+        type: "constant"
+        concurrency: 2
+        times: 10
+      context:
+        users:
+          tenants: 2
+          users_per_tenant: 2
+      sla:
+        failure_rate:
+          max: 0

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

@@ -26,3 +26,18 @@ class NovaHostsTestCase(test.TestCase):
         scenario._list_hosts = mock.Mock()
         scenario.run(zone=None)
         scenario._list_hosts.assert_called_once_with(None)
+
+    def test_list_and_get_hosts(self):
+        fake_hosts = [mock.Mock(host_name="fake_hostname")]
+        scenario = hosts.ListAndGetHosts()
+        scenario._list_hosts = mock.MagicMock(
+            return_value=fake_hosts)
+        scenario._get_host = mock.MagicMock()
+        scenario.run(zone="nova")
+
+        scenario._list_hosts.assert_called_once_with("nova")
+        scenario._get_host.assert_called_once_with(
+            "fake_hostname", atomic_action=False)
+
+        self._test_atomic_action_timer(scenario.atomic_actions(),
+                                       "nova.get_1_hosts")

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

@@ -889,6 +889,17 @@ class NovaScenarioTestCase(test.ScenarioTestCase):
         self._test_atomic_action_timer(nova_scenario.atomic_actions(),
                                        "nova.search_hypervisors")
 
+    def test__get_host(self):
+        nova_scenario = utils.NovaScenario()
+        result = nova_scenario._get_host("host_name")
+        self.assertEqual(
+            self.admin_clients("nova").hosts.get.return_value,
+            result)
+        self.admin_clients("nova").hosts.get.assert_called_once_with(
+            "host_name")
+        self._test_atomic_action_timer(nova_scenario.atomic_actions(),
+                                       "nova.get_host")
+
     def test__list_images(self):
         nova_scenario = utils.NovaScenario()
         result = nova_scenario._list_images(detailed=False, fakearg="fakearg")