Make interfaces_client use **kwargs

As we discussed on
http://lists.openstack.org/pipermail/openstack-dev/2015-July/068864.html
All http POST/PUT methods need to contain **kwargs as their arguments.
This patch makes interfaces_client use **kwargs.

Partially implements blueprint consistent-service-method-names

Change-Id: I18a1b5cd224912f937f1ea39ff0053bf5e6b36ff
diff --git a/tempest/api/compute/servers/test_attach_interfaces.py b/tempest/api/compute/servers/test_attach_interfaces.py
index 396327b..9e27f33 100644
--- a/tempest/api/compute/servers/test_attach_interfaces.py
+++ b/tempest/api/compute/servers/test_attach_interfaces.py
@@ -98,7 +98,7 @@
     def _test_create_interface_by_network_id(self, server, ifs):
         network_id = ifs[0]['net_id']
         iface = self.client.create_interface(server['id'],
-                                             network_id=network_id)
+                                             net_id=network_id)
         iface = self.wait_for_interface_status(
             server['id'], iface['port_id'], 'ACTIVE')
         self._check_interface(iface, network_id=network_id)
@@ -179,7 +179,7 @@
         self.assertTrue(interface_count > 0)
         self._check_interface(ifs[0])
         network_id = ifs[0]['net_id']
-        self.client.add_fixed_ip(server['id'], network_id)
+        self.client.add_fixed_ip(server['id'], networkId=network_id)
         # Remove the fixed IP from server.
         server_detail = self.os.servers_client.show_server(
             server['id'])
@@ -192,4 +192,4 @@
                     break
             if fixed_ip is not None:
                 break
-        self.client.remove_fixed_ip(server['id'], fixed_ip)
+        self.client.remove_fixed_ip(server['id'], address=fixed_ip)
diff --git a/tempest/scenario/test_network_basic_ops.py b/tempest/scenario/test_network_basic_ops.py
index ff58eea..e676063 100644
--- a/tempest/scenario/test_network_basic_ops.py
+++ b/tempest/scenario/test_network_basic_ops.py
@@ -244,7 +244,7 @@
         old_port = port_list[0]
         interface = self.interface_client.create_interface(
             server_id=server['id'],
-            network_id=self.new_net.id)
+            net_id=self.new_net.id)
         self.addCleanup(self.network_client.wait_for_resource_deletion,
                         'port',
                         interface['port_id'])
diff --git a/tempest/services/compute/json/interfaces_client.py b/tempest/services/compute/json/interfaces_client.py
index e8b2b64..c437c08 100644
--- a/tempest/services/compute/json/interfaces_client.py
+++ b/tempest/services/compute/json/interfaces_client.py
@@ -29,16 +29,8 @@
         return service_client.ResponseBodyList(resp,
                                                body['interfaceAttachments'])
 
-    def create_interface(self, server_id, port_id=None, network_id=None,
-                         fixed_ip=None):
-        post_body = dict(interfaceAttachment=dict())
-        if port_id:
-            post_body['interfaceAttachment']['port_id'] = port_id
-        if network_id:
-            post_body['interfaceAttachment']['net_id'] = network_id
-        if fixed_ip:
-            fip = dict(ip_address=fixed_ip)
-            post_body['interfaceAttachment']['fixed_ips'] = [fip]
+    def create_interface(self, server_id, **kwargs):
+        post_body = {'interfaceAttachment': kwargs}
         post_body = json.dumps(post_body)
         resp, body = self.post('servers/%s/os-interface' % server_id,
                                body=post_body)
@@ -59,26 +51,18 @@
         self.validate_response(schema.delete_interface, resp, body)
         return service_client.ResponseBody(resp, body)
 
-    def add_fixed_ip(self, server_id, network_id):
+    def add_fixed_ip(self, server_id, **kwargs):
         """Add a fixed IP to input server instance."""
-        post_body = json.dumps({
-            'addFixedIp': {
-                'networkId': network_id
-            }
-        })
+        post_body = json.dumps({'addFixedIp': kwargs})
         resp, body = self.post('servers/%s/action' % server_id,
                                post_body)
         self.validate_response(servers_schema.server_actions_common_schema,
                                resp, body)
         return service_client.ResponseBody(resp, body)
 
-    def remove_fixed_ip(self, server_id, ip_address):
+    def remove_fixed_ip(self, server_id, **kwargs):
         """Remove input fixed IP from input server instance."""
-        post_body = json.dumps({
-            'removeFixedIp': {
-                'address': ip_address
-            }
-        })
+        post_body = json.dumps({'removeFixedIp': kwargs})
         resp, body = self.post('servers/%s/action' % server_id,
                                post_body)
         self.validate_response(servers_schema.server_actions_common_schema,