Enable resource metadata history in Gnocchi client

This patch will enable the feature that is being introduced via PR gnocchixyz/gnocchi#1059.

gnocchiclient/v1/aggregates.py

@@ -24,7 +24,8 @@
 class AggregatesManager(base.Manager):
     def fetch(self, operations, search=None,
               resource_type='generic', start=None, stop=None, granularity=None,
-              needed_overlap=None, groupby=None, fill=None, details=False):
+              needed_overlap=None, groupby=None, fill=None, details=False,
+              use_history=False):
         """Get measurements of an aggregated metrics.
 
         :param operations: operations
@@ -44,6 +45,10 @@ def fetch(self, operations, search=None,
         :param details: also returns the list of metrics or resources
                         associated to the operations
         :type details: boolean
+        :param use_history: indicates if Gnocchi server must include in the
+                            response the tag history for resources. The
+                            default value is `False`.
+        :type use_history: boolean
 
         See Gnocchi REST API documentation for the format
         of *query dictionary*
@@ -66,6 +71,8 @@ def fetch(self, operations, search=None,
             data["resource_type"] = resource_type
             params["groupby"] = groupby
 
+        params['use_history'] = use_history
+
         aggregates = self._post("v1/aggregates?%s" % (
             utils.dict_to_querystring(params)),
             headers={'Content-Type': "application/json"},

gnocchiclient/v1/aggregates_cli.py

@@ -42,7 +42,16 @@ def get_parser(self, prog_name):
         parser.add_argument("--fill",
                             help=("Value to use when backfilling timestamps "
                                   "with missing values in a subset of series. "
-                                  "Value should be a float or 'null'."))
+                                  "Value should be a float or 'null'.")),
+        parser.add_argument("--use-history", default=False,
+                            help=("Indicates if Gnocchi server should respond "
+                                  "with the resource tags history for the "
+                                  "aggregation query. If set to `False`, only "
+                                  "the latest tag values will be returned. "
+                                  "Otherwise, the measures will be split "
+                                  "proportionally if a tag has been changed "
+                                  "in the `granularity` requested.")
+                            )
         return parser
 
     def take_action(self, parsed_args):
@@ -55,6 +64,7 @@ def take_action(self, parsed_args):
             granularity=parsed_args.granularity,
             needed_overlap=parsed_args.needed_overlap,
             groupby=parsed_args.groupby,
+            use_history=parsed_args.use_history
         )
 
         if parsed_args.search and parsed_args.groupby: