Add interfaces functional negative tests

The negative tests of interfaces API are not covered enough
in functional tests. We want to add the conflict tests of when
this API runs in the unexpected state (e.g. not ACTIVE) of server.

Change-Id: I4bea067a729db735524689a5cbe49cceab23b51c

nova/tests/functional/api/client.py

@@ -408,3 +408,11 @@ class TestOpenStackClient(object):
         """
         return self.api_put('/servers/%s/tags' % server_id,
                             {'tags': tags}).body['tags']
+
+    def get_port_interfaces(self, server_id):
+        return self.api_get('/servers/%s/os-interface' %
+                            (server_id)).body['interfaceAttachments']
+
+    def detach_interface(self, server_id, port_id):
+        return self.api_delete('/servers/%s/os-interface/%s' %
+                               (server_id, port_id))

nova/tests/functional/wsgi/test_interfaces.py

@@ -1,4 +1,4 @@
-# Copyright 2016 NTT Corporation.
+# Copyright 2017 NTT Corporation.
 #
 # All Rights Reserved.
 #
@@ -15,7 +15,9 @@
 # under the License.
 
 from nova.tests import fixtures as nova_fixtures
+from nova.tests.functional.api import client
 from nova.tests.functional import integrated_helpers
+from nova.tests.functional import test_servers
 from nova.tests.unit import policy_fixture
 from nova.tests import uuidsentinel as uuids
 
@@ -93,3 +95,50 @@ class InterfaceFullstack(integrated_helpers._IntegratedTestBase):
         resp = self.api.api_post(os_interface_url, body,
                                  check_response_status=False)
         self.assertEqual(400, resp.status)
+
+
+class InterfaceFullstackWithNeutron(test_servers.ServersTestBase):
+    """Tests for port interfaces command.
+
+    Functional Test Scope:
+
+    This test uses Neutron.
+    os-interface API specifies a port ID created by Neutron.
+
+    """
+    api_major_version = 'v2.1'
+    USE_NEUTRON = True
+
+    def setUp(self):
+        super(InterfaceFullstackWithNeutron, self).setUp()
+        self.useFixture(nova_fixtures.NeutronFixture(self))
+
+    def test_detach_interface_negative_invalid_state(self):
+        # Create server with network
+        image = self.api.get_images()[0]['id']
+        post = {"server": {"name": "test", "flavorRef": "1",
+            "imageRef": image,
+            "networks": [{"uuid": "3cb9bc59-5699-4588-a4b1-b87f96708bc6"}]}}
+        created_server = self.api.post_server(post)
+        created_server_id = created_server['id']
+        found_server = self._wait_for_state_change(created_server, 'BUILD')
+        self.assertEqual('ACTIVE', found_server['status'])
+
+        response = self.api.get_port_interfaces(created_server_id)[0]
+        port_id = response['port_id']
+
+        # Change status from ACTIVE to SUSPENDED for negative test
+        post = {'suspend': {}}
+        self.api.post_server_action(created_server_id, post)
+        found_server = self._wait_for_state_change(found_server, 'ACTIVE')
+        self.assertEqual('SUSPENDED', found_server['status'])
+
+        # Detach port interface in SUSPENDED (not ACTIVE, etc.)
+        ex = self.assertRaises(client.OpenStackApiException,
+                               self.api.detach_interface,
+                               created_server_id, port_id)
+        self.assertEqual(409, ex.response.status_code)
+        self.assertEqual('SUSPENDED', found_server['status'])
+
+        # Cleanup
+        self._delete_server(created_server_id)