Don't check for project-id if accessing the / route

The versions route (or / route) should be publicly accessible and is
used for keystone discovery. We shouldn't be checking for the
project-id if that's accessed. On the other hand, this also fixes the
issue where the server crashes if no version is given.

Change-Id: I0481ef6f3920c8ee56ea79ed5621206246b26299
Closes-Bug: #1609662

zaqar/common/transport/wsgi/helpers.py

@@ -91,14 +91,19 @@ def extract_project_id(req, resp, params):
     :type params: dict
     :rtype: None
     """
+    api_version_string = req.path.split('/')[1]
     params['project_id'] = req.get_header('X-PROJECT-ID')
+    if not api_version_string:
+        # NOTE(jaosorior): The versions resource is public and shouldn't need
+        # a check for the project-id.
+        return
     if params['project_id'] == "":
         raise falcon.HTTPBadRequest('Empty project header not allowed',
                                     _(u'X-PROJECT-ID cannot be an empty '
                                       u'string. Specify the right header '
                                       u'X-PROJECT-ID and retry.'))
 
-    api_version = LooseVersion(req.path.split('/')[1])
+    api_version = LooseVersion(api_version_string)
     if not params['project_id'] and api_version >= LooseVersion('v1.1'):
         raise falcon.HTTPBadRequest('Project-Id Missing',
                                     _(u'The header X-PROJECT-ID was missing'))

zaqar/tests/functional/wsgi/test_versions.py

@@ -0,0 +1,36 @@
+# Copyright (c) 2016 Red Hat, Inc.
+#
+# 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 zaqar.tests.functional import base
+
+
+class TestVersions(base.FunctionalTestBase):
+
+    """Tests for Versions Resource."""
+
+    server_class = base.ZaqarServer
+
+    def setUp(self):
+        super(TestVersions, self).setUp()
+        self.base_url = "{url}/".format(url=self.cfg.zaqar.url)
+        self.client.set_base_url(self.base_url)
+
+    def test_get_versions_without_headers(self):
+        result = self.client.get('', headers={})
+        self.assertIn("versions", result.json())
+
+    def test_get_versions_with_headers(self):
+        result = self.client.get('')
+        self.assertIn("versions", result.json())