adds tests for CINDER encryption volume-type APIs

This patch adds the JSON tests for CINDER encryption volume-type V1 APIs.
It also adds the JSON clients for following APIs :
1. cinder encryption-type-delete

Change-Id: I20a68684f950fe36653eb4304edb56e244867ca3
diff --git a/tempest/api/volume/admin/test_volume_types.py b/tempest/api/volume/admin/test_volume_types.py
index ee1d09a..3b8c214 100644
--- a/tempest/api/volume/admin/test_volume_types.py
+++ b/tempest/api/volume/admin/test_volume_types.py
@@ -118,14 +118,16 @@
                          'from the created Volume_type')
 
     @test.attr(type='smoke')
-    def test_volume_type_encryption_create_get(self):
-        # Create/get encryption type.
+    def test_volume_type_encryption_create_get_delete(self):
+        # Create/get/delete encryption type.
         provider = "LuksEncryptor"
         control_location = "front-end"
         name = data_utils.rand_name("volume-type-")
         resp, body = self.client.create_volume_type(name)
         self.assertEqual(200, resp.status)
         self.addCleanup(self._delete_volume_type, body['id'])
+
+        # Create encryption type
         resp, encryption_type = self.client.create_encryption_type(
             body['id'], provider=provider,
             control_location=control_location)
@@ -137,6 +139,8 @@
         self.assertEqual(control_location, encryption_type['control_location'],
                          "The created encryption_type control_location is not "
                          "equal to the requested control_location")
+
+        # Get encryption type
         resp, fetched_encryption_type = self.client.get_encryption_type(
             encryption_type['volume_type_id'])
         self.assertEqual(200, resp.status)
@@ -148,3 +152,15 @@
                          fetched_encryption_type['control_location'],
                          'The fetched encryption_type control_location is '
                          'different from the created encryption_type')
+
+        # Delete encryption type
+        resp, _ = self.client.delete_encryption_type(
+            encryption_type['volume_type_id'])
+        self.assertEqual(202, resp.status)
+        resource = {"id": encryption_type['volume_type_id'],
+                    "type": "encryption-type"}
+        self.client.wait_for_resource_deletion(resource)
+        resp, deleted_encryption_type = self.client.get_encryption_type(
+            encryption_type['volume_type_id'])
+        self.assertEqual(200, resp.status)
+        self.assertEmpty(deleted_encryption_type)
diff --git a/tempest/services/volume/json/admin/volume_types_client.py b/tempest/services/volume/json/admin/volume_types_client.py
index c9c0582..65ecc67 100644
--- a/tempest/services/volume/json/admin/volume_types_client.py
+++ b/tempest/services/volume/json/admin/volume_types_client.py
@@ -18,6 +18,7 @@
 
 from tempest.common import rest_client
 from tempest import config
+from tempest import exceptions
 
 CONF = config.CONF
 
@@ -34,6 +35,26 @@
         self.build_interval = CONF.volume.build_interval
         self.build_timeout = CONF.volume.build_timeout
 
+    def is_resource_deleted(self, resource):
+        # to use this method self.resource must be defined to respective value
+        # Resource is a dictionary containing resource id and type
+        # Resource : {"id" : resource_id
+        #             "type": resource_type}
+        try:
+            if resource['type'] == "volume-type":
+                self.get_volume_type(resource['id'])
+            elif resource['type'] == "encryption-type":
+                resp, body = self.get_encryption_type(resource['id'])
+                assert 200 == resp.status
+                if not body:
+                    return True
+            else:
+                msg = (" resource value is either not defined or incorrect.")
+                raise exceptions.UnprocessableEntity(msg)
+        except exceptions.NotFound:
+            return True
+        return False
+
     def list_volume_types(self, params=None):
         """List all the volume_types created."""
         url = 'types'
@@ -150,3 +171,7 @@
         resp, body = self.post(url, post_body)
         body = json.loads(body)
         return resp, body['encryption']
+
+    def delete_encryption_type(self, vol_type_id):
+        """Delete the encryption type for the specified volume-type."""
+        return self.delete("/types/%s/encryption/provider" % str(vol_type_id))