Split out Neutron metering label rules client

Splitting out a metering label rules client for Neutron.

Partially implements blueprint consistent-service-method-names

Change-Id: Iddecde5f6f5c1ac88a18d71aab1fc26370b26ba8
diff --git a/tempest/api/network/base.py b/tempest/api/network/base.py
index b4ea29b..c5a3dff 100644
--- a/tempest/api/network/base.py
+++ b/tempest/api/network/base.py
@@ -98,9 +98,12 @@
                     floating_ip['id'])
 
             # Clean up metering label rules
+            # Not all classes in the hierarchy have the client class variable
+            if len(cls.metering_label_rules) > 0:
+                label_rules_client = cls.admin_metering_label_rules_client
             for metering_label_rule in cls.metering_label_rules:
                 cls._try_delete_resource(
-                    cls.admin_client.delete_metering_label_rule,
+                    label_rules_client.delete_metering_label_rule,
                     metering_label_rule['id'])
             # Clean up metering labels
             for metering_label in cls.metering_labels:
@@ -273,6 +276,8 @@
         cls.admin_ports_client = cls.os_adm.ports_client
         cls.admin_floating_ips_client = cls.os_adm.floating_ips_client
         cls.admin_metering_labels_client = cls.os_adm.metering_labels_client
+        cls.admin_metering_label_rules_client = (
+            cls.os_adm.metering_label_rules_client)
 
     @classmethod
     def create_metering_label(cls, name, description):
@@ -288,7 +293,8 @@
     def create_metering_label_rule(cls, remote_ip_prefix, direction,
                                    metering_label_id):
         """Wrapper utility that returns a test metering label rule."""
-        body = cls.admin_client.create_metering_label_rule(
+        client = cls.admin_metering_label_rules_client
+        body = client.create_metering_label_rule(
             remote_ip_prefix=remote_ip_prefix, direction=direction,
             metering_label_id=metering_label_id)
         metering_label_rule = body['metering_label_rule']
diff --git a/tempest/api/network/test_metering_extensions.py b/tempest/api/network/test_metering_extensions.py
index c4021b4..007ba3b 100644
--- a/tempest/api/network/test_metering_extensions.py
+++ b/tempest/api/network/test_metering_extensions.py
@@ -59,12 +59,11 @@
         self.assertEqual(len(labels['metering_labels']), 0)
 
     def _delete_metering_label_rule(self, metering_label_rule_id):
+        client = self.admin_metering_label_rules_client
         # Deletes a rule and verifies if it is deleted or not
-        self.admin_client.delete_metering_label_rule(
-            metering_label_rule_id)
+        client.delete_metering_label_rule(metering_label_rule_id)
         # Asserting that the rule is not found in list after deletion
-        rules = (self.admin_client.list_metering_label_rules(
-                 id=metering_label_rule_id))
+        rules = client.list_metering_label_rules(id=metering_label_rule_id)
         self.assertEqual(len(rules['metering_label_rules']), 0)
 
     @test.idempotent_id('e2fb2f8c-45bf-429a-9f17-171c70444612')
@@ -105,8 +104,9 @@
 
     @test.idempotent_id('cc832399-6681-493b-9d79-0202831a1281')
     def test_list_metering_label_rules(self):
+        client = self.admin_metering_label_rules_client
         # Verify rule filtering
-        body = self.admin_client.list_metering_label_rules(id=33)
+        body = client.list_metering_label_rules(id=33)
         metering_label_rules = body['metering_label_rules']
         self.assertEqual(0, len(metering_label_rules))
 
@@ -115,7 +115,8 @@
         # Creates a rule
         remote_ip_prefix = ("10.0.1.0/24" if self._ip_version == 4
                             else "fd03::/64")
-        body = (self.admin_client.create_metering_label_rule(
+        client = self.admin_metering_label_rules_client
+        body = (client.create_metering_label_rule(
                 remote_ip_prefix=remote_ip_prefix,
                 direction="ingress",
                 metering_label_id=self.metering_label['id']))
@@ -124,14 +125,14 @@
                         metering_label_rule['id'])
         # Assert whether created rules are found in rules list or fail
         # if created rules are not found in rules list
-        rules = (self.admin_client.list_metering_label_rules(
-                 id=metering_label_rule['id']))
+        rules = client.list_metering_label_rules(id=metering_label_rule['id'])
         self.assertEqual(len(rules['metering_label_rules']), 1)
 
     @test.idempotent_id('b7354489-96ea-41f3-9452-bace120fb4a7')
     def test_show_metering_label_rule(self):
         # Verifies the details of a rule
-        body = (self.admin_client.show_metering_label_rule(
+        client = self.admin_metering_label_rules_client
+        body = (client.show_metering_label_rule(
                 self.metering_label_rule['id']))
         metering_label_rule = body['metering_label_rule']
         self.assertEqual(self.metering_label_rule['id'],