Add support for faults

Added:

* Faults manager - a compnent for managing faults (load them,
connect os-faults to cloud, exdcute faults, etc.).

* Faults for test_floatingip test class

Also, modified test_floatingip tests to run faults
if faults manager set up properly (loaded configuration file,
managed to connect the nodes of the cloud, etc.).

Change-Id: I1dd48bc9a7cc385a46d9b3b2382000581a614b42

Pipfile

@@ -4,8 +4,9 @@ verify_ssl = true
 name = "pypi"
 
 [packages]
-tobiko = {editable = true, path = "."}
+tobiko = {editable = true,path = "."}
 ansible = "*"
+testscenarios = "*"
 
 [dev-packages]
 

extra-requirements.txt

@@ -1,4 +1,5 @@
-# Optional tobiko requirements
+# Tobiko extra requirements
 
 ansible>=2.4.0       # GPLv3
+os-faults>=0.1.18    # Apache-2.0
 tempest>=17.1.0      # Apache-2.0

requirements.txt

@@ -7,3 +7,4 @@ python-heatclient>=1.5.0     # Apache-2.0
 python-neutronclient>=6.7.0  # Apache-2.0
 stestr>=2.0                  # Apache-2.0
 testtools>=2.2.0             # MIT
+testscenarios>=0.4           # Apache-2.0/BSD

tobiko/common/managers/fault.py

@@ -0,0 +1,72 @@
+# Copyright 2018 Red Hat
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+from __future__ import absolute_import
+
+import os
+
+import os_faults
+import yaml
+
+from oslo_log import log
+
+LOG = log.getLogger(__name__)
+
+try:
+    FileNotFoundError
+except NameError:
+    FileNotFoundError = IOError  # pylint: disable=redefined-builtin
+
+CONF_DIR = os.path.expanduser('~')
+CONF_FILE = 'os-faults.yaml'
+
+
+class FaultManager():
+    """Manages faults."""
+
+    def __init__(self, test_file):
+        self.faults_dir = os.path.join(os.path.dirname(test_file), 'faults')
+        faults_f_name = os.path.splitext(os.path.basename(test_file))[0]
+        self.faults_file = os.path.join(self.faults_dir, faults_f_name)
+        fault_config_f = os.path.join(CONF_DIR, CONF_FILE)
+        try:
+            self.cloud = os_faults.connect(config_filename=fault_config_f)
+            self.cloud.verify()
+            self.scenarios = self.get_scenarios()
+        except os_faults.ansible.executor.AnsibleExecutionUnreachable:
+            LOG.warning("Couldn't verify connectivity to the"
+                        " cloud with os-faults configuration")
+            self.scenarios = None
+        except FileNotFoundError:
+            LOG.warning("Couldn't find os-faults configuration file")
+            self.scenarios = None
+
+    def get_scenarios(self):
+        """Returns list of scenarios based on defined faults.
+
+        A scenario composed out of scenario name and the fault to execute.
+        """
+        scenarios = []
+        with open(self.faults_file, 'r') as stream:
+            faults_yaml = yaml.load(stream)
+            for fault in faults_yaml:
+                scenarios.append((fault['name'], dict(fault=fault['action'])))
+            return scenarios
+
+    def run_fault(self, fault):
+        """Executes given fault."""
+        if self.scenarios:
+            os_faults.human_api(self.cloud, fault)
+        else:
+            LOG.debug("Skipped fault: '{}' since".format(fault),
+                      " scenarios are not defined.")

tobiko/common/managers/fixture.py

@@ -73,7 +73,7 @@ FIXTURES = FixtureManager()
 
 class FixtureMeta(abc.ABCMeta):
 
-    def __new__(cls, name, bases, members):
+    def __new__(cls, name, bases, members):  # pylint: disable=arguments-differ
         fixture_class = super(FixtureMeta, cls).__new__(cls, name, bases,
                                                         members)
         if not inspect.isabstract(fixture_class):

tobiko/tests/scenario/base.py

@@ -32,6 +32,7 @@ class ScenarioTestsBase(base.TobikoTest):
     templates_dir = os.path.join(os.path.dirname(__file__), 'templates')
     stacks = stack_manager.StackManager(clients, templates_dir)
     stack = None
+    fault = None
 
     @classmethod
     def setUpClass(cls):

tobiko/tests/scenario/faults/test_floatingip

@@ -0,0 +1,2 @@
+- name: 'Restart OVS'
+  action: 'restart openvswitch service'

tobiko/tests/scenario/test_floatingip.py

@@ -14,13 +14,24 @@
 #    under the License.
 from __future__ import absolute_import
 
+import testscenarios
+from testscenarios.scenarios import multiply_scenarios
+
 from tobiko.tests.scenario import base
 from tobiko.common.asserts import assert_ping
+from tobiko.common.managers import fault
+
+load_tests = testscenarios.load_tests_apply_scenarios
 
 
 class FloatingIPTest(base.ScenarioTestsBase):
     """Tests server connectivity"""
 
+    fault_manager = fault.FaultManager(__file__)
+    test_faults = fault_manager.scenarios
+    if test_faults:
+        scenarios = multiply_scenarios(test_faults)
+
     @classmethod
     def setUpClass(cls):
         super(FloatingIPTest, cls).setUpClass()
@@ -29,7 +40,9 @@ class FloatingIPTest(base.ScenarioTestsBase):
 
     def test_ping_floating_ip(self):
         """Validates connectivity to a server post upgrade."""
+        self.fault_manager.run_fault(self.fault)
         assert_ping(self.fip)
 
     def test_ping_unreachable_floating_ip(self):
+        self.fault_manager.run_fault(self.fault)
         assert_ping(self.unreachable_fip, should_fail=True)