Add a required_api_version validator

New validator required_api_version is introduced to validating
the api version needed to run the scenario.

This patch also adds the validator to the keystone v2 specific
scenarios.

Change-Id: I1cd97d88545fa3a363009e36515f5ae1cb5bc3a9
Closes-bug: #1442633

rally/plugins/openstack/scenarios/keystone/basic.py

@@ -64,6 +64,7 @@ class KeystoneBasic(kutils.KeystoneScenario):
         self._resource_delete(user)
 
     @validation.required_openstack(admin=True)
+    @validation.required_api_versions(component="keystone", versions=[2.0])
     @scenario.configure(context={"admin_cleanup": ["keystone"]})
     @logging.log_deprecated_args(
         "The 'name_length' argument to create_tenant is ignored",
@@ -77,6 +78,7 @@ class KeystoneBasic(kutils.KeystoneScenario):
 
     @validation.number("users_per_tenant", minval=1)
     @validation.required_openstack(admin=True)
+    @validation.required_api_versions(component="keystone", versions=[2.0])
     @scenario.configure(context={"admin_cleanup": ["keystone"]})
     @logging.log_deprecated_args(
         "The 'name_length' argument to create_tenant_with_users is ignored",
@@ -107,6 +109,7 @@ class KeystoneBasic(kutils.KeystoneScenario):
         self._list_users()
 
     @validation.required_openstack(admin=True)
+    @validation.required_api_versions(component="keystone", versions=[2.0])
     @scenario.configure(context={"admin_cleanup": ["keystone"]})
     @logging.log_deprecated_args(
         "The 'name_length' argument to create_and_list_tenants is ignored",
@@ -147,6 +150,7 @@ class KeystoneBasic(kutils.KeystoneScenario):
         self._list_roles_for_user(user_id, tenant_id)
 
     @validation.required_openstack(admin=True)
+    @validation.required_api_versions(component="keystone", versions=[2.0])
     @scenario.configure(context={"admin_cleanup": ["keystone"]})
     def get_entities(self, service_name="keystone"):
         """Get instance of a tenant, user, role and service by id's.
@@ -190,6 +194,7 @@ class KeystoneBasic(kutils.KeystoneScenario):
         self._delete_service(service.id)
 
     @validation.required_openstack(admin=True)
+    @validation.required_api_versions(component="keystone", versions=[2.0])
     @scenario.configure(context={"admin_cleanup": ["keystone"]})
     @logging.log_deprecated_args(
         "The 'name_length' argument to create_update_and_delete_tenant is "

rally/task/validation.py

@@ -611,6 +611,35 @@ def required_openstack(config, clients, deployment, admin=False, users=False):
         return ValidationResult(False, _("Admin credentials required"))
 
 
+@validator
+def required_api_versions(config, clients, deployment, component, versions):
+    """Validator checks component API versions."""
+    versions = [str(v) for v in versions]
+    versions_str = ", ".join(versions)
+    msg = _("Task was designed to be used with %(component)s "
+            "V%(version)s, but V%(found_version)s is "
+            "selected.")
+    if component == "keystone":
+        if "2.0" in versions and not hasattr(clients.keystone(), "tenants"):
+            return ValidationResult(False, msg % {"component": component,
+                                                  "version": versions_str,
+                                                  "found_version": "3"})
+        if "3" in versions and not hasattr(clients.keystone(), "projects"):
+            return ValidationResult(False, msg % {"component": component,
+                                                  "version": versions_str,
+                                                  "found_version": "2.0"})
+    else:
+        used_version = getattr(clients, component).choose_version()
+        if not used_version:
+            return ValidationResult(
+                False, _("Unable to determine the API version."))
+        if str(used_version) not in versions:
+            return ValidationResult(
+                False, msg % {"component": component,
+                              "version": versions_str,
+                              "found_version": used_version})
+
+
 @validator
 def volume_type_exists(config, clients, deployment, param_name):
     """Returns validator for volume types.

tests/unit/task/test_validation.py

@@ -883,3 +883,33 @@ class ValidatorsTestCase(test.TestCase):
             self.assertEqual("Heat template validation failed on fake_path1."
                              " Original error message: fake_msg.", result.msg)
             self.assertFalse(result.is_valid)
+
+    def test_required_api_versions(self):
+        validatorv2 = self._unwrap_validator(
+            validation.required_api_versions, component="keystone",
+            versions=[2.0])
+        clients = mock.MagicMock()
+        if hasattr(clients.keystone(), "tenants"):
+            del clients.keystone().tenants
+        self.assertFalse(validatorv2(None, clients, None).is_valid)
+        clients.keystone().tenants = mock.MagicMock
+        self.assertTrue(validatorv2(None, clients, None).is_valid)
+
+        validatorv3 = self._unwrap_validator(
+            validation.required_api_versions, component="keystone",
+            versions=[3])
+        if hasattr(clients.keystone(), "projects"):
+            del clients.keystone().projects
+        self.assertFalse(validatorv3(None, clients, None).is_valid)
+        clients.keystone().projects = mock.MagicMock
+        self.assertTrue(validatorv3(None, clients, None).is_valid)
+
+        validatorother = self._unwrap_validator(
+            validation.required_api_versions, component="nova",
+            versions=[2])
+        clients.nova.choose_version.return_value = 2
+        self.assertTrue(validatorother(None, clients, None).is_valid)
+        clients.nova.choose_version.return_value = 3
+        self.assertFalse(validatorother(None, clients, None).is_valid)
+        clients.nova.choose_version.return_value = None
+        self.assertFalse(validatorother(None, clients, None).is_valid)