(feat): Add versions controller for UCP integration compliance,

This PS adds the versions controller to Armada for UCP integration
compliance. It's responsible for returning information about
each of Armada's API versions.

Change-Id: I0ad5f0578ab97a50b30e8322647347aa1ed962dd

armada/api/controller/versions.py

@@ -0,0 +1,36 @@
+# Copyright 2017 AT&T Intellectual Property.  All other 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 json
+
+import falcon
+
+from armada import api
+
+
+class Versions(api.BaseResource):
+    """Versions resource
+
+    Returns the list of supported versions of the Armada API.
+    """
+
+    def on_get(self, req, resp):
+        resp.status = falcon.HTTP_200
+        resp.body = json.dumps({
+            'v1.0': {
+                'path': '/api/v1.0',
+                'status': 'stable'
+            }
+        })
+        resp.content_type = 'application/json'

armada/api/server.py

@@ -28,6 +28,7 @@ from armada.api.controller.health import Health
 from armada.api.controller.tiller import Release
 from armada.api.controller.tiller import Status
 from armada.api.controller.validation import Validate
+from armada.api.controller.versions import Versions
 
 conf.set_app_default_configs()
 CONF = cfg.CONF
@@ -64,6 +65,7 @@ def create(enable_middleware=CONF.middleware):
 
     for route, service in url_routes_v1:
         api.add_route("/api/v1.0/{}".format(route), service)
+    api.add_route('/versions', Versions())
 
     # Initialize policy config options.
     policy.Enforcer(CONF)

armada/tests/unit/api/test_versions_controller.py

@@ -0,0 +1,31 @@
+# Copyright 2017 AT&T Intellectual Property.  All other 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.
+
+from armada.tests.unit.api import base
+
+
+class VersionsControllerTest(base.BaseControllerTest):
+
+    def test_list_versions(self):
+        """
+        Validate that /api/v1.0/health returns 204.
+        """
+        result = self.app.simulate_get('/versions')
+        expected = {
+            'v1.0': {
+                'path': '/api/v1.0',
+                'status': 'stable'
+            }
+        }
+        self.assertDictEqual(expected, result.json)