Revised cluster model and clusterpolicy model

We make the following operations actions of clusters:
 - cluster_policy_attach
 - cluster_policy_detach
 - cluster_policy_update
 - cluster_policy_enable
 - cluster_policy_disable

We don't allow create, update, delete operations on the ClusterPolicy
model. The reason is due to OpenStack SDK restrictions, we cannot make
the ClusterPolicy binding ID transparent, while most of the time users
will use cluster ID/name and policy ID/name directly.

senlinclient/v1/models.py

@@ -306,6 +306,64 @@ class Cluster(resource.Resource):
         }
         return self.action(session, body)
 
+    def policy_attach(self, session, policy_id, priority, level, cooldown,
+                      enabled):
+        body = {
+            'policy_attach': {
+                'policy_id': policy_id,
+                'priority': priority,
+                'level': level,
+                'cooldown': cooldown,
+                'enabled': enabled,
+            }
+        }
+        return self.action(session, body)
+
+    def policy_detach(self, session, policy_id):
+        body = {
+            'policy_detach': {
+                'policy_id': policy_id,
+            }
+        }
+        return self.action(session, body)
+
+    def policy_update(self, session, policy_id, priority, level, cooldown,
+                      enabled):
+
+        body = {
+            'policy_update': {
+                'policy_id': policy_id,
+            }
+        }
+        if priority is not None:
+            body['policy_update']['priority'] = priority
+        if level is not None:
+            body['policy_update']['level'] = level
+        if cooldown is not None:
+            body['policy_update']['cooldown'] = cooldown
+        if enabled is not None:
+            body['policy_update']['enabled'] = enabled
+
+        return self.action(session, body)
+
+    def policy_enable(self, session, policy_id):
+        body = {
+            'policy_update': {
+                'policy_id': policy_id,
+                'enabled': True,
+            }
+        }
+        return self.action(session, body)
+
+    def policy_disable(self, session, policy_id):
+        body = {
+            'policy_update': {
+                'policy_id': policy_id,
+                'enabled': False,
+            }
+        }
+        return self.action(session, body)
+
     def to_dict(self):
         info = {
             'id': self.id,
@@ -339,9 +397,6 @@ class ClusterPolicy(resource.Resource):
     # Capabilities
     allow_list = True
     allow_retrieve = True
-    allow_create = True
-    allow_delete = True
-    allow_update = True
 
     # Properties
     id = resource.prop('id')