network: add metering api operations

This patch aims to bring new tests related to Neutron Metering plugin.

They cover:
- List / Create / Show / Delete metering labels
- List / Create / Show / Delete metering label rules

Note: Update operation is not covered by the API.
Also add basic operations in network admin client.

Change-Id: Ieaf9a5dcd52f54e015e7565f50a3ea81569c483a
Signed-off-by: Emilien Macchi <emilien.macchi@enovance.com>
diff --git a/tempest/api/network/base.py b/tempest/api/network/base.py
index b129786..0f73aca 100644
--- a/tempest/api/network/base.py
+++ b/tempest/api/network/base.py
@@ -75,6 +75,8 @@
         cls.vpnservices = []
         cls.ikepolicies = []
         cls.floating_ips = []
+        cls.metering_labels = []
+        cls.metering_label_rules = []
 
     @classmethod
     def tearDownClass(cls):
@@ -107,6 +109,13 @@
         # Clean up pools
         for pool in cls.pools:
             cls.client.delete_pool(pool['id'])
+        # Clean up metering label rules
+        for metering_label_rule in cls.metering_label_rules:
+            cls.admin_client.delete_metering_label_rule(
+                metering_label_rule['id'])
+        # Clean up metering labels
+        for metering_label in cls.metering_labels:
+            cls.admin_client.delete_metering_label(metering_label['id'])
         # Clean up ports
         for port in cls.ports:
             cls.client.delete_port(port['id'])
@@ -287,3 +296,24 @@
         else:
             cls.os_adm = clients.ComputeAdminManager(interface=cls._interface)
         cls.admin_client = cls.os_adm.network_client
+
+    @classmethod
+    def create_metering_label(cls, name, description):
+        """Wrapper utility that returns a test metering label."""
+        resp, body = cls.admin_client.create_metering_label(
+            description=description,
+            name=data_utils.rand_name("metering-label"))
+        metering_label = body['metering_label']
+        cls.metering_labels.append(metering_label)
+        return metering_label
+
+    @classmethod
+    def create_metering_label_rule(cls, remote_ip_prefix, direction,
+                                   metering_label_id):
+        """Wrapper utility that returns a test metering label rule."""
+        resp, body = cls.admin_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']
+        cls.metering_label_rules.append(metering_label_rule)
+        return metering_label_rule