Add Octavia (load_balancer) load balancer failover

This patch adds a Octavia (load_balancer) load balancer failover method.

It also corrects the resource documentation for the Octavia stats resource
classes.

Depends-On: https://review.openstack.org/634344
Change-Id: I7384351a5b59b2d68d6a45c543449815adfe52f2

doc/source/user/proxies/load_balancer_v2.rst

@@ -22,6 +22,7 @@ Load Balancer Operations
    .. automethod:: openstack.load_balancer.v2._proxy.Proxy.get_load_balancer_statistics
    .. automethod:: openstack.load_balancer.v2._proxy.Proxy.load_balancers
    .. automethod:: openstack.load_balancer.v2._proxy.Proxy.update_load_balancer
+   .. automethod:: openstack.load_balancer.v2._proxy.Proxy.failover_load_balancer
 
 Listener Operations
 ^^^^^^^^^^^^^^^^^^^

doc/source/user/resources/load_balancer/v2/listener.rst

@@ -10,3 +10,12 @@ The ``Listener`` class inherits from :class:`~openstack.resource.Resource`.
 
 .. autoclass:: openstack.load_balancer.v2.listener.Listener
    :members:
+
+The ListenerStats Class
+-----------------------
+
+The ``ListenerStats`` class inherits from
+:class:`~openstack.resource.Resource`.
+
+.. autoclass:: openstack.load_balancer.v2.listener.ListenerStats
+   :members:

doc/source/user/resources/load_balancer/v2/load_balancer.rst

@@ -10,3 +10,21 @@ The ``LoadBalancer`` class inherits from :class:`~openstack.resource.Resource`.
 
 .. autoclass:: openstack.load_balancer.v2.load_balancer.LoadBalancer
    :members:
+
+The LoadBalancerStats Class
+---------------------------
+
+The ``LoadBalancerStats`` class inherits from
+:class:`~openstack.resource.Resource`.
+
+.. autoclass:: openstack.load_balancer.v2.load_balancer.LoadBalancerStats
+   :members:
+
+The LoadBalancerFailover Class
+------------------------------
+
+The ``LoadBalancerFailover`` class inherits from
+:class:`~openstack.resource.Resource`.
+
+.. autoclass:: openstack.load_balancer.v2.load_balancer.LoadBalancerFailover
+   :members:

openstack/load_balancer/v2/_proxy.py

@@ -126,6 +126,15 @@ class Proxy(proxy.Proxy):
         return resource.wait_for_status(self, lb, status, failures, interval,
                                         wait, attribute='provisioning_status')
 
+    def failover_load_balancer(self, name_or_id, **attrs):
+        """Failover a load balancer
+
+        :param name_or_id: The name or ID of a load balancer
+
+        :returns: ``None``
+        """
+        return self._update(_lb.LoadBalancerFailover, lb_id=name_or_id)
+
     def create_listener(self, **attrs):
         """Create a new listener from attributes
 

openstack/load_balancer/v2/load_balancer.py

@@ -33,7 +33,7 @@ class LoadBalancer(resource.Resource, resource.TagMixin):
         **resource.TagMixin._tag_query_parameters
     )
 
-    #: Properties
+    # Properties
     #: The administrative state of the load balancer *Type: bool*
     is_admin_state_up = resource.Body('admin_state_up', type=bool)
     #: Timestamp when the load balancer was created
@@ -113,3 +113,38 @@ class LoadBalancerStats(resource.Resource):
     request_errors = resource.Body('request_errors', type=int)
     #: The total connections handled.
     total_connections = resource.Body('total_connections', type=int)
+
+
+class LoadBalancerFailover(resource.Resource):
+    base_path = '/lbaas/loadbalancers/%(lb_id)s/failover'
+
+    # capabilities
+    allow_create = False
+    allow_fetch = False
+    allow_commit = True
+    allow_delete = False
+    allow_list = False
+
+    requires_id = False
+
+    # Properties
+    #: The ID of the load balancer.
+    lb_id = resource.URI('lb_id')
+
+    # The parent commit method assumes there is a header or body change,
+    # which we do not have here. The default _update code path also has no
+    # way to pass has_body into this function, so overriding the method here.
+    def commit(self, session, base_path=None):
+        kwargs = {}
+        request = self._prepare_request(prepend_key=False,
+                                        base_path=base_path,
+                                        **kwargs)
+        session = self._get_session(session)
+        kwargs = {}
+        microversion = self._get_microversion_for(session, 'commit')
+        response = session.put(request.url, json=request.body,
+                               headers=request.headers,
+                               microversion=microversion, **kwargs)
+        self.microversion = microversion
+        self._translate_response(response, has_body=False)
+        return self

openstack/tests/functional/load_balancer/v2/test_load_balancer.py

@@ -228,6 +228,13 @@ class TestLoadBalancer(base.BaseFunctionalTest):
         test_lb = self.conn.load_balancer.get_load_balancer(self.LB_ID)
         self.assertEqual(self.LB_NAME, test_lb.name)
 
+    def test_lb_failover(self):
+        self.conn.load_balancer.failover_load_balancer(self.LB_ID)
+        self.conn.load_balancer.wait_for_load_balancer(
+            self.LB_ID, wait=self._wait_for_timeout)
+        test_lb = self.conn.load_balancer.get_load_balancer(self.LB_ID)
+        self.assertEqual(self.LB_NAME, test_lb.name)
+
     def test_listener_find(self):
         test_listener = self.conn.load_balancer.find_listener(
             self.LISTENER_NAME)

openstack/tests/unit/load_balancer/test_load_balancer.py

@@ -187,3 +187,16 @@ class TestLoadBalancerStats(base.TestCase):
                          test_load_balancer.request_errors)
         self.assertEqual(EXAMPLE_STATS['total_connections'],
                          test_load_balancer.total_connections)
+
+
+class TestLoadBalancerFailover(base.TestCase):
+
+    def test_basic(self):
+        test_load_balancer = load_balancer.LoadBalancerFailover()
+        self.assertEqual('/lbaas/loadbalancers/%(lb_id)s/failover',
+                         test_load_balancer.base_path)
+        self.assertFalse(test_load_balancer.allow_create)
+        self.assertFalse(test_load_balancer.allow_fetch)
+        self.assertFalse(test_load_balancer.allow_delete)
+        self.assertFalse(test_load_balancer.allow_list)
+        self.assertTrue(test_load_balancer.allow_commit)

openstack/tests/unit/load_balancer/test_proxy.py

@@ -97,6 +97,13 @@ class TestLoadBalancerProxy(test_proxy_base.TestProxyBase):
         self.verify_update(self.proxy.update_load_balancer,
                            lb.LoadBalancer)
 
+    def test_load_balancer_failover(self):
+        self.verify_update(self.proxy.failover_load_balancer,
+                           lb.LoadBalancerFailover,
+                           value=[self.LB_ID],
+                           expected_args=[],
+                           expected_kwargs={'lb_id': self.LB_ID})
+
     def test_listeners(self):
         self.verify_list(self.proxy.listeners,
                          listener.Listener)

releasenotes/notes/add-octavia-lb-failover-9a34c9577d78ad34.yaml

@@ -0,0 +1,4 @@
+---
+features:
+  - |
+    Added Octavia (load_balancer) load balancer failover.