Don't use SessionClient for version-list API

The endpoint of version API doesn't contain "/v2/{project-id}" and it is
just "/". SessionClient is based on the endpoint "/v2/{project-id}/...",
so this patch makes a client use a raw url for version-list API.

Change-Id: I53f2afacce2dda14ac9761e824b48887f7c192f9
Closes-Bug: #1444235

novaclient/tests/functional/test_readonly_nova.py

@@ -156,6 +156,9 @@ class SimpleReadOnlyNovaClientTest(base.ClientTestBase):
         self.nova('migration-list')
         self.nova('migration-list', flags='--debug')
 
+    def test_version_list(self):
+        self.nova('version-list')
+
     # Optional arguments:
 
     def test_admin_version(self):

novaclient/tests/unit/v2/fakes.py

@@ -64,15 +64,21 @@ class FakeHTTPClient(base_client.HTTPClient):
         elif method == 'PUT':
             assert 'body' in kwargs
 
-        # Call the method
-        args = parse.parse_qsl(parse.urlparse(url)[4])
-        kwargs.update(args)
-        munged_url = url.rsplit('?', 1)[0]
-        munged_url = munged_url.strip('/').replace('/', '_').replace('.', '_')
-        munged_url = munged_url.replace('-', '_')
-        munged_url = munged_url.replace(' ', '_')
+        if url is not None:
+            # Call the method
+            args = parse.parse_qsl(parse.urlparse(url)[4])
+            kwargs.update(args)
+            munged_url = url.rsplit('?', 1)[0]
+            munged_url = munged_url.strip('/').replace('/', '_')
+            munged_url = munged_url.replace('.', '_')
+            munged_url = munged_url.replace('-', '_')
+            munged_url = munged_url.replace(' ', '_')
+            callback = "%s_%s" % (method.lower(), munged_url)
 
-        callback = "%s_%s" % (method.lower(), munged_url)
+        if url is None or callback == "get_http:__nova_api:8774":
+            # To get API version information, it is necessary to GET
+            # a nova endpoint directly without "v2/<tenant-id>".
+            callback = "get_versions"
 
         if not hasattr(self, callback):
             raise AssertionError('Called unknown API method: %s %s, '
@@ -90,6 +96,26 @@ class FakeHTTPClient(base_client.HTTPClient):
         })
         return r, body
 
+    def get_endpoint(self):
+        return "http://nova-api:8774/v2/190a755eef2e4aac9f06aa6be9786385"
+
+    def get_versions(self):
+        return (200, {}, {
+            "versions": [
+                {"status": "SUPPORTED", "updated": "2011-01-21T11:33:21Z",
+                 "links": [{"href": "http://nova-api:8774/v2/",
+                            "rel": "self"}],
+                 "min_version": "",
+                 "version": "",
+                 "id": "v2.0"},
+                {"status": "CURRENT", "updated": "2013-07-23T11:33:21Z",
+                 "links": [{"href": "http://nova-api:8774/v2.1/",
+                            "rel": "self"}],
+                 "min_version": "2.1",
+                 "version": "2.3",
+                 "id": "v2.1"}
+            ]})
+
     #
     # agents
     #

novaclient/tests/unit/v2/test_versions.py

@@ -0,0 +1,38 @@
+# 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 mock
+
+from novaclient.tests.unit import utils
+from novaclient.tests.unit.v2 import fakes
+from novaclient.v2 import versions
+
+
+class VersionsTest(utils.TestCase):
+    def setUp(self):
+        super(VersionsTest, self).setUp()
+        self.cs = fakes.FakeClient()
+        self.service_type = versions.Version
+
+    @mock.patch.object(versions.VersionManager, '_is_session_client',
+                       return_value=False)
+    def test_list_services_with_http_client(self, mock_is_session_client):
+        self.cs.versions.list()
+        self.cs.assert_called('GET', None)
+
+    @mock.patch.object(versions.VersionManager, '_is_session_client',
+                       return_value=True)
+    def test_list_services_with_session_client(self, mock_is_session_client):
+        self.cs.versions.list()
+        self.cs.assert_called('GET', 'http://nova-api:8774/')

novaclient/v2/versions.py

@@ -16,7 +16,10 @@
 version interface
 """
 
+from six.moves import urllib
+
 from novaclient import base
+from novaclient import client
 
 
 class Version(base.Resource):
@@ -30,6 +33,19 @@ class Version(base.Resource):
 class VersionManager(base.ManagerWithFind):
     resource_class = Version
 
+    def _is_session_client(self):
+        return isinstance(self.api.client, client.SessionClient)
+
     def list(self):
         """List all versions."""
-        return self._list(None, "versions")
+
+        version_url = None
+        if self._is_session_client():
+            # NOTE: "list versions" API needs to be accessed without base
+            # URI (like "v2/{project-id}"), so here should be a scheme("http",
+            # etc.) and a hostname.
+            endpoint = self.api.client.get_endpoint()
+            url = urllib.parse.urlparse(endpoint)
+            version_url = '%s://%s/' % (url.scheme, url.netloc)
+
+        return self._list(version_url, "versions")