Replace voluptuous with JSONSchema to validate change_node_power_state

Now in watcher,both JSONSchema and voluptuous are used to validate
JSON payloads. We want to remove voluptuous and Use
JSONSchema as our only JSON validation tool to keep consistence
and also to make it easier to expose the validation schema
through our API in future work.

In this patch, we replace voluptuous with JSONSchema to validate
the change_node_power_state action in watcher applier.

Partially Implements: blueprint jsonschema-validation

Change-Id: If9ffe5e0b107e0da5673247e4d5ec9917790827f

watcher/tests/applier/actions/test_change_node_power_state.py

@@ -15,8 +15,8 @@
 
 from __future__ import unicode_literals
 
+import jsonschema
 import mock
-import voluptuous
 
 from watcher.applier.actions import base as baction
 from watcher.applier.actions import change_node_power_state
@@ -59,34 +59,21 @@ class TestChangeNodePowerState(base.TestCase):
         self.action.input_parameters = {
             baction.BaseAction.RESOURCE_ID: COMPUTE_NODE,
             self.action.STATE: 'error'}
-        exc = self.assertRaises(
-            voluptuous.Invalid, self.action.validate_parameters)
-        self.assertEqual(
-            [(['state'], voluptuous.ScalarInvalid)],
-            [([str(p) for p in e.path], type(e)) for e in exc.errors])
+        self.assertRaises(jsonschema.ValidationError,
+                          self.action.validate_parameters)
 
     def test_parameters_resource_id_empty(self, mock_ironic, mock_nova):
         self.action.input_parameters = {
             self.action.STATE:
                 change_node_power_state.NodeState.POWERON.value,
         }
-        exc = self.assertRaises(
-            voluptuous.Invalid, self.action.validate_parameters)
-        self.assertEqual(
-            [(['resource_id'], voluptuous.RequiredFieldInvalid)],
-            [([str(p) for p in e.path], type(e)) for e in exc.errors])
+        self.assertRaises(jsonschema.ValidationError,
+                          self.action.validate_parameters)
 
     def test_parameters_applies_add_extra(self, mock_ironic, mock_nova):
         self.action.input_parameters = {"extra": "failed"}
-        exc = self.assertRaises(
-            voluptuous.Invalid, self.action.validate_parameters)
-        self.assertEqual(
-            sorted([(['resource_id'], voluptuous.RequiredFieldInvalid),
-                    (['state'], voluptuous.RequiredFieldInvalid),
-                    (['extra'], voluptuous.Invalid)],
-                   key=lambda x: str(x[0])),
-            sorted([([str(p) for p in e.path], type(e)) for e in exc.errors],
-                   key=lambda x: str(x[0])))
+        self.assertRaises(jsonschema.ValidationError,
+                          self.action.validate_parameters)
 
     def test_change_service_state_pre_condition(self, mock_ironic, mock_nova):
         try: