Support for node replace in cluster service

This patch adds support for "cluster members replace" in cluster service:
1\ add cluster_replace_nodes in _proxy.py
2\ add replace_nodes in cluster.py
3\ add related unit tests

partial-blueprint: support-cluster-replace-action
https://blueprints.launchpad.net/senlin/+spec/support-cluster-replace-action

Change-Id: I57bb835ae9ca31317b2ddd37958ddbdf64df20df

openstack/cluster/v1/_proxy.py

@@ -303,6 +303,20 @@ class Proxy(proxy2.BaseProxy):
             obj = self._find(_cluster.Cluster, cluster, ignore_missing=False)
         return obj.del_nodes(self.session, nodes)
 
+    def cluster_replace_nodes(self, cluster, nodes):
+        """Replace the nodes in a cluster with specified nodes.
+
+        :param cluster: Either the name or the ID of the cluster, or an
+            instance of :class:`~openstack.cluster.v1.cluster.Cluster`.
+        :param nodes: List of nodes to be deleted/added to the cluster.
+        :returns: A dict containing the action initiated by this operation.
+        """
+        if isinstance(cluster, _cluster.Cluster):
+            obj = cluster
+        else:
+            obj = self._find(_cluster.Cluster, cluster, ignore_missing=False)
+        return obj.replace_nodes(self.session, nodes)
+
     def cluster_scale_out(self, cluster, count=None):
         """Inflate the size of a cluster.
 

openstack/cluster/v1/cluster.py

@@ -98,6 +98,14 @@ class Cluster(resource.Resource):
         }
         return self.action(session, body)
 
+    def replace_nodes(self, session, nodes):
+        body = {
+            'replace_nodes': {
+                'nodes': nodes,
+            }
+        }
+        return self.action(session, body)
+
     def scale_out(self, session, count=None):
         body = {
             'scale_out': {

openstack/tests/unit/cluster/v1/test_cluster.py

@@ -165,6 +165,19 @@ class TestCluster(testtools.TestCase):
         sess.post.assert_called_once_with(url, endpoint_filter=sot.service,
                                           json=body)
 
+    def test_replace_nodes(self):
+        sot = cluster.Cluster(**FAKE)
+
+        resp = mock.Mock()
+        resp.json = mock.Mock(return_value='')
+        sess = mock.Mock()
+        sess.post = mock.Mock(return_value=resp)
+        self.assertEqual('', sot.replace_nodes(sess, {'node-22': 'node-44'}))
+        url = 'clusters/%s/actions' % sot.id
+        body = {'replace_nodes': {'nodes': {'node-22': 'node-44'}}}
+        sess.post.assert_called_once_with(url, endpoint_filter=sot.service,
+                                          json=body)
+
     def test_policy_attach(self):
         sot = cluster.Cluster(**FAKE)
 

openstack/tests/unit/cluster/v1/test_proxy.py

@@ -143,6 +143,24 @@ class TestClusterProxy(test_proxy_base2.TestProxyBase):
                      method_args=[mock_cluster, ["node1"]],
                      expected_args=[["node1"]])
 
+    @mock.patch.object(proxy_base.BaseProxy, '_find')
+    def test_cluster_replace_nodes(self, mock_find):
+        mock_cluster = cluster.Cluster.new(id='FAKE_CLUSTER')
+        mock_find.return_value = mock_cluster
+        self._verify("openstack.cluster.v1.cluster.Cluster.replace_nodes",
+                     self.proxy.cluster_replace_nodes,
+                     method_args=["FAKE_CLUSTER", {"node1": "node2"}],
+                     expected_args=[{"node1": "node2"}])
+        mock_find.assert_called_once_with(cluster.Cluster, "FAKE_CLUSTER",
+                                          ignore_missing=False)
+
+    def test_cluster_replace_nodes_with_obj(self):
+        mock_cluster = cluster.Cluster.new(id='FAKE_CLUSTER')
+        self._verify("openstack.cluster.v1.cluster.Cluster.replace_nodes",
+                     self.proxy.cluster_replace_nodes,
+                     method_args=[mock_cluster, {"node1": "node2"}],
+                     expected_args=[{"node1": "node2"}])
+
     @mock.patch.object(proxy_base.BaseProxy, '_find')
     def test_cluster_scale_out(self, mock_find):
         mock_cluster = cluster.Cluster.new(id='FAKE_CLUSTER')