Add functional test for version negotiation

the test attempts to make an unauthenticated request to the Heat API
root.

Change-Id: Ib14628927efe561744cda683ca4dcf27b0524e20
Story: 2002531
Task: 22077

heat_integrationtests/functional/test_versionnegotiation.py

@@ -0,0 +1,36 @@
+#    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 requests
+
+from heat_integrationtests.functional import functional_base
+
+expected_version_dict = {
+    "versions": [
+        {"links": [{"href": None, "rel": "self"}],
+         "status": "CURRENT", "id": "v1.0"}
+    ]
+}
+
+
+class VersionNegotiationTestCase(functional_base.FunctionalTestsBase):
+
+    def test_authless_version_negotiation(self):
+        # NOTE(pas-ha): this will grab the public endpoint by default
+        heat_url = self.identity_client.get_endpoint_url(
+            'orchestration', region=self.conf.region)
+        heat_api_root = heat_url.split('/v1')[0]
+        expected_version_dict[
+            'versions'][0]['links'][0]['href'] = heat_api_root + '/v1/'
+        r = requests.get(heat_api_root)
+        self.assertEqual(300, r.status_code, 'got response %s' % r.text)
+        self.assertEqual(expected_version_dict, r.json())