Switch task parser to custom yaml

1.Switch task parser to custom yaml, custom yaml deprecates duplicate key
and loads task in the same order as they are in task file.
2.Remove duplicate scenario KeystoneBasic.create_delete_user.

Change-Id: I3b338f63eca0ac217a6376f6d6705da69fb97e80

rally-jobs/rally-keystone-api-v2.yaml

@@ -197,17 +197,6 @@
         failure_rate:
           max: 0
 
-  KeystoneBasic.create_delete_user:
-    -
-      args: {}
-      runner:
-        type: "constant"
-        times: 10
-        concurrency: 10
-      sla:
-        failure_rate:
-          max: 0
-
   KeystoneBasic.create_and_delete_service:
     -
       runner:

rally-jobs/rally-mos.yaml

@@ -116,17 +116,6 @@
         failure_rate:
           max: 0
 
-  KeystoneBasic.create_delete_user:
-    -
-      args: {}
-      runner:
-        type: "constant"
-        times: 1
-        concurrency: 1
-      sla:
-        failure_rate:
-          max: 0
-
   HeatStacks.create_and_list_stack:
     -
       args:

rally-jobs/rally.yaml

@@ -197,17 +197,6 @@
         failure_rate:
           max: 0
 
-  KeystoneBasic.create_delete_user:
-    -
-      args: {}
-      runner:
-        type: "constant"
-        times: 10
-        concurrency: 10
-      sla:
-        failure_rate:
-          max: 0
-
   KeystoneBasic.create_and_delete_service:
     -
       runner:

rally/cli/commands/task.py

@@ -26,7 +26,6 @@ import jsonschema
 from oslo_utils import uuidutils
 import six
 from six.moves.urllib import parse as urlparse
-import yaml
 
 from rally.cli import cliutils
 from rally.cli import envutils
@@ -36,6 +35,7 @@ from rally.common.io import junit
 from rally.common import logging
 from rally.common import utils as rutils
 from rally.common import version
+from rally.common import yamlutils as yaml
 from rally import consts
 from rally import exceptions
 from rally import plugins
@@ -80,7 +80,7 @@ class TaskCommands(object):
             try:
                 kw = args and yaml.safe_load(args)
                 kw = {} if kw is None else kw
-            except yaml.parser.ParserError as e:
+            except yaml.ParserError as e:
                 print_invalid_header(src_name, args)
                 print(_("%(source)s has to be YAML or JSON. Details:"
                         "\n\n%(err)s\n")

rally/task/context.py

@@ -75,12 +75,12 @@ class BaseContext(plugin.Plugin, functional.FunctionalMixin,
         # NOTE(amaretskiy): self.config is a constant data and must be
         #                   immutable or write-protected type to prevent
         #                   unexpected changes in runtime
-        if type(config) == dict:
+        if isinstance(config, dict):
             if hasattr(self, "DEFAULT_CONFIG"):
                 for key, value in self.DEFAULT_CONFIG.items():
                     config.setdefault(key, value)
             self.config = utils.LockedDict(config)
-        elif type(config) == list:
+        elif isinstance(config, list):
             self.config = tuple(config)
         else:
             # NOTE(amaretskiy): It is improbable that config can be a None,

rally/task/validation.py

@@ -21,10 +21,10 @@ import re
 from glanceclient import exc as glance_exc
 from novaclient import exceptions as nova_exc
 import six
-import yaml
 
 from rally.common.i18n import _
 from rally.common import objects
+from rally.common import yamlutils as yaml
 from rally import consts
 from rally import exceptions
 from rally import osclients
@@ -171,7 +171,7 @@ def file_exists(config, clients, deployment, param_name, mode=os.R_OK,
 def check_command_dict(command):
     """Check command-specifying dict `command', raise ValueError on error."""
 
-    if type(command) != dict:
+    if not isinstance(command, dict):
         raise ValueError("Command must be a dictionary")
 
     # NOTE(pboldin): Here we check for the values not for presence of the keys

tests/unit/task/test_validation.py

@@ -923,7 +923,7 @@ class ValidatorsTestCase(test.TestCase):
                          valid)
 
     @mock.patch(
-        "yaml.safe_load",
+        "rally.common.yamlutils.safe_load",
         return_value={
             "version": "2.0",
             "name": "wb",