Get rid of decorator lib

This lib is used only in two places and the latest release fails now.

Change-Id: Ia79008c6ac7dc3be92afdea5f8ffabcd697e7599

rally/cli/envutils.py

@@ -13,12 +13,13 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+import functools
+import inspect
 import os
 
-import decorator
-
 from rally import exceptions
 
+
 PATH_GLOBALS = "~/.rally/globals"
 ENV_ENV = "RALLY_ENV"
 ENV_DEPLOYMENT = "RALLY_DEPLOYMENT"
@@ -124,16 +125,23 @@ def get_global(global_key, do_raise=False):
 def default_from_global(arg_name, env_name,
                         cli_arg_name,
                         message=MSG_MISSING_ARG):
-    def default_from_global(f, *args, **kwargs):
-        id_arg_index = f.__code__.co_varnames.index(arg_name)
-        args = list(args)
-        if args[id_arg_index] is None:
-            args[id_arg_index] = get_global(env_name)
-            if not args[id_arg_index]:
-                print(message % {"arg_name": cli_arg_name})
-                return(1)
-        return f(*args, **kwargs)
-    return decorator.decorator(default_from_global)
+    def wrapper(func):
+
+        @functools.wraps(func)
+        def inner(*args, **kwargs):
+            params = list(inspect.signature(func).parameters)
+            id_arg_index = params.index(arg_name)
+
+            args = list(args)
+            if ((len(args) <= id_arg_index or args[id_arg_index] is None)
+                    and arg_name not in kwargs):
+                kwargs[arg_name] = get_global(env_name)
+                if not kwargs[arg_name]:
+                    print(message % {"arg_name": cli_arg_name})
+                    return 1
+            return func(*args, **kwargs)
+        return inner
+    return wrapper
 
 
 def with_default_env():

rally/plugins/__init__.py

@@ -13,10 +13,9 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+import functools
 import os
 
-import decorator
-
 from rally.common.plugin import discover
 
 
@@ -53,7 +52,9 @@ def load():
     PLUGINS_LOADED = True
 
 
-@decorator.decorator
-def ensure_plugins_are_loaded(f, *args, **kwargs):
-    load()
-    return f(*args, **kwargs)
+def ensure_plugins_are_loaded(func):
+    @functools.wraps(func)
+    def wrapper(*args, **kwargs):
+        load()
+        return func(*args, **kwargs)
+    return wrapper

requirements.txt

@@ -4,7 +4,6 @@
 
 # Rally core dependencies
 alembic!=1.2.0                                         # MIT
-decorator                                              # new BSD License
 Jinja2                                                 # BSD-3-Clause
 jsonschema                                             # MIT
 oslo.config!=4.3.0,!=4.4.0                             # Apache Software License

tox.ini

@@ -77,7 +77,7 @@ deps =
   -r{toxinidir}/doc/requirements.txt
 commands =
   rm -rf doc/build
-  sphinx-build -b html doc/source doc/build/html
+  sphinx-build -v -b html doc/source doc/build/html
 
 [testenv:genconfig]
 commands =
@@ -153,6 +153,7 @@ filterwarnings =
     ignore:invalid escape sequence:DeprecationWarning:.*netaddr.*
     ignore:invalid escape sequence:DeprecationWarning:.*prettytable
     ignore:invalid escape sequence:DeprecationWarning:.*subunit.*
+    ignore:invalid escape sequence:DeprecationWarning:.*docutils.*
     # python 3.7
     ignore:Using or importing the ABCs:DeprecationWarning:unittest2.*
     # python 3.8