Add unit test for agents_client

We have a plan to migrate service clients to tempest-lib from Tempest.
However, we are not doing enough tests for service clients now.
This patch adds unit test for agents_client. After that, we can add
tests for each service client.

Change-Id: I0519c6d0f689de19075640c5842dfea39adc7617
diff --git a/tempest/tests/services/__init__.py b/tempest/tests/services/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/tempest/tests/services/__init__.py
diff --git a/tempest/tests/services/compute/__init__.py b/tempest/tests/services/compute/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/tempest/tests/services/compute/__init__.py
diff --git a/tempest/tests/services/compute/test_agents_client.py b/tempest/tests/services/compute/test_agents_client.py
new file mode 100644
index 0000000..e8ea525
--- /dev/null
+++ b/tempest/tests/services/compute/test_agents_client.py
@@ -0,0 +1,50 @@
+# Copyright 2015 NEC Corporation.  All rights reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+import httplib2
+
+from oslotest import mockpatch
+
+from tempest.services.compute.json import agents_client
+from tempest.tests import base
+from tempest.tests import fake_auth_provider
+from tempest.tests import fake_config
+
+
+class TestAgentsClient(base.TestCase):
+
+    def setUp(self):
+        super(TestAgentsClient, self).setUp()
+        self.useFixture(fake_config.ConfigFixture())
+        fake_auth = fake_auth_provider.FakeAuthProvider()
+        self.client = agents_client.AgentsClient(fake_auth,
+                                                 'compute', 'regionOne')
+
+    def _test_list_agents(self, bytes_body=False):
+        if bytes_body:
+            body = bytes(b'{"agents": []}')
+        else:
+            body = '{"agents": []}'
+        expected = []
+        response = (httplib2.Response({'status': 200}), body)
+        self.useFixture(mockpatch.Patch(
+            'tempest.common.service_client.ServiceClient.get',
+            return_value=response))
+        self.assertEqual(expected, self.client.list_agents())
+
+    def test_list_agents_with_str_body(self):
+        self._test_list_agents()
+
+    def test_list_agents_with_bytes_body(self):
+        self._test_list_agents(bytes_body=True)