Merge "Adds API version discovery support for V3"

2013-09-02 10:34:02 +00:00 · 2013-09-02 10:34:02 +00:00 · 88fb94f5fa
commit 88fb94f5fa
parent 7c9e6a8a39 a1baa247a4
10 changed files with 503 additions and 14 deletions
--- a/doc/api_samples/versions-get-resp.json
+++ b/doc/api_samples/versions-get-resp.json
@ -10,6 +10,17 @@
            ],
            "status": "CURRENT",
            "updated": "2011-01-21T11:33:21Z"
+        },
+        {
+            "id": "v3.0",
+            "links": [
+                {
+                    "href": "http://openstack.example.com/v3/",
+                    "rel": "self"
+                }
+            ],
+            "status": "EXPERIMENTAL",
+            "updated": "2013-07-23T11:33:21Z"
        }
    ]
-}
+}
--- a/doc/api_samples/versions-get-resp.xml
+++ b/doc/api_samples/versions-get-resp.xml
@ -3,4 +3,7 @@
  <version status="CURRENT" updated="2011-01-21T11:33:21Z" id="v2.0">
    <atom:link href="http://openstack.example.com/v2/" rel="self"/>
  </version>
-</versions>
+  <version status="EXPERIMENTAL" updated="2013-07-23T11:33:21Z" id="v3.0">
+    <atom:link href="http://openstack.example.com/v3/" rel="self"/>
+  </version>
+</versions>
--- a/nova/api/openstack/compute/plugins/v3/versions.py
+++ b/nova/api/openstack/compute/plugins/v3/versions.py
@ -0,0 +1,57 @@
+# vim: tabstop=4 shiftwidth=4 softtabstop=4
+
+# Copyright 2013 IBM Corp.
+# 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.
+
+from nova.api.openstack.compute import versions
+from nova.api.openstack.compute.views import versions as views_versions
+from nova.api.openstack import extensions
+from nova.api.openstack import wsgi
+
+
+ALIAS = "versions"
+
+
+class VersionsController(object):
+    @extensions.expected_errors(())
+    @wsgi.serializers(xml=versions.VersionTemplate,
+                      atom=versions.VersionAtomSerializer)
+    def show(self, req):
+        builder = views_versions.get_view_builder(req)
+        return builder.build_version(versions.VERSIONS['v3.0'])
+
+
+class Versions(extensions.V3APIExtensionBase):
+    """API Version information."""
+
+    name = "Versions"
+    alias = ALIAS
+    namespace = "http://docs.openstack.org/compute/core/versions/v3"
+    version = 1
+
+    def get_resources(self):
+        resources = [
+            extensions.ResourceExtension(ALIAS, VersionsController(),
+                                         custom_routes_fn=self.version_map)]
+        return resources
+
+    def get_controller_extensions(self):
+        return []
+
+    def version_map(self, mapper, wsgi_resource):
+        mapper.connect("versions", "/",
+                       controller=wsgi_resource,
+                       action='show', conditions={"method": ['GET']})
+        mapper.redirect("", "/")
--- a/nova/api/openstack/compute/versions.py
+++ b/nova/api/openstack/compute/versions.py
@ -16,6 +16,7 @@
 #    under the License.

 from lxml import etree
+from oslo.config import cfg

 from nova.api.openstack.compute.views import versions as views_versions
 from nova.api.openstack import wsgi
@ -23,6 +24,9 @@ from nova.api.openstack import xmlutil
 from nova.openstack.common import timeutils


+CONF = cfg.CONF
+CONF.import_opt('enabled', 'nova.api.openstack', group='osapi_v3')
+
 LINKS = {
   'v2.0': {
       'pdf': 'http://docs.openstack.org/'
@ -30,6 +34,12 @@ LINKS = {
       'wadl': 'http://docs.openstack.org/'
               'api/openstack-compute/2/wadl/os-compute-2.wadl'
    },
+   'v3.0': {
+       'pdf': 'http://docs.openstack.org/'
+               'api/openstack-compute/3/os-compute-devguide-3.pdf',
+       'wadl': 'http://docs.openstack.org/'
+               'api/openstack-compute/3/wadl/os-compute-3.wadl'
+    },
 }


@ -60,6 +70,33 @@ VERSIONS = {
                "type": "application/vnd.openstack.compute+json;version=2",
            }
        ],
+    },
+    "v3.0": {
+        "id": "v3.0",
+        "status": "EXPERIMENTAL",
+        "updated": "2013-07-23T11:33:21Z",
+        "links": [
+            {
+                "rel": "describedby",
+                "type": "application/pdf",
+                "href": LINKS['v3.0']['pdf'],
+            },
+            {
+                "rel": "describedby",
+                "type": "application/vnd.sun.wadl+xml",
+                "href": LINKS['v3.0']['wadl'],
+            },
+        ],
+        "media-types": [
+            {
+                "base": "application/xml",
+                "type": "application/vnd.openstack.compute+xml;version=3",
+            },
+            {
+                "base": "application/json",
+                "type": "application/vnd.openstack.compute+json;version=3",
+            }
+        ],
    }
 }

@ -205,6 +242,8 @@ class VersionAtomSerializer(AtomSerializer):
 class Versions(wsgi.Resource):
    def __init__(self):
        super(Versions, self).__init__(None)
+        if not CONF.osapi_v3.enabled:
+            del VERSIONS["v3.0"]

    @wsgi.serializers(xml=VersionsTemplate,
                      atom=VersionsAtomSerializer)
--- a/nova/api/openstack/compute/views/versions.py
+++ b/nova/api/openstack/compute/views/versions.py
@ -44,7 +44,7 @@ class ViewBuilder(common.ViewBuilder):
                "links": [
                    {
                        "rel": "self",
-                        "href": self.generate_href(req.path),
+                        "href": self.generate_href(version['id'], req.path),
                    },
                ],
                "media-types": version['media-types'],
@ -75,7 +75,7 @@ class ViewBuilder(common.ViewBuilder):

    def _build_links(self, version_data):
        """Generate a container of links that refer to the provided version."""
-        href = self.generate_href()
+        href = self.generate_href(version_data['id'])

        links = [
            {
@ -86,10 +86,14 @@ class ViewBuilder(common.ViewBuilder):

        return links

-    def generate_href(self, path=None):
+    def generate_href(self, version, path=None):
        """Create an url that refers to a specific version_number."""
        prefix = self._update_compute_link_prefix(self.base_url)
-        version_number = 'v2'
+        if version.find('v3.') == 0:
+            version_number = 'v3'
+        else:
+            version_number = 'v2'
+
        if path:
            path = path.strip('/')
            return os.path.join(prefix, version_number, path)
--- a/nova/tests/api/openstack/compute/plugins/v3/test_versions.py
+++ b/nova/tests/api/openstack/compute/plugins/v3/test_versions.py
@ -0,0 +1,246 @@
+# vim: tabstop=4 shiftwidth=4 softtabstop=4
+
+# Copyright 2013 IBM Corp.
+# Copyright 2010-2011 OpenStack Foundation
+#
+#    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 feedparser
+from lxml import etree
+import webob
+
+from nova.api.openstack import xmlutil
+from nova.openstack.common import jsonutils
+from nova import test
+from nova.tests.api.openstack import common
+from nova.tests.api.openstack import fakes
+
+
+NS = {
+    'atom': 'http://www.w3.org/2005/Atom',
+    'ns': 'http://docs.openstack.org/common/api/v1.0'
+}
+
+
+EXP_LINKS = {
+   'v3.0': {
+       'pdf': 'http://docs.openstack.org/'
+               'api/openstack-compute/3/os-compute-devguide-3.pdf',
+       'wadl': 'http://docs.openstack.org/'
+               'api/openstack-compute/3/wadl/os-compute-3.wadl'
+    },
+}
+
+
+EXP_VERSIONS = {
+    "v3.0": {
+        "id": "v3.0",
+        "status": "EXPERIMENTAL",
+        "updated": "2013-07-23T11:33:21Z",
+        "links": [
+            {
+                "rel": "describedby",
+                "type": "application/pdf",
+                "href": EXP_LINKS['v3.0']['pdf'],
+            },
+            {
+                "rel": "describedby",
+                "type": "application/vnd.sun.wadl+xml",
+                "href": EXP_LINKS['v3.0']['wadl'],
+            },
+        ],
+        "media-types": [
+            {
+                "base": "application/xml",
+                "type": "application/vnd.openstack.compute+xml;version=3",
+            },
+            {
+                "base": "application/json",
+                "type": "application/vnd.openstack.compute+json;version=3",
+            }
+        ],
+    }
+}
+
+
+class VersionsTest(test.TestCase):
+
+    def test_get_version_list_302(self):
+        req = webob.Request.blank('/v3')
+        req.accept = "application/json"
+        res = req.get_response(fakes.wsgi_app_v3())
+        self.assertEqual(res.status_int, 302)
+        redirect_req = webob.Request.blank('/v3/')
+        self.assertEqual(res.location, redirect_req.url)
+
+    def test_get_version_3_detail(self):
+        req = webob.Request.blank('/v3/')
+        req.accept = "application/json"
+        res = req.get_response(fakes.wsgi_app_v3())
+        self.assertEqual(res.status_int, 200)
+        self.assertEqual(res.content_type, "application/json")
+        version = jsonutils.loads(res.body)
+        expected = {
+            "version": {
+                "id": "v3.0",
+                "status": "EXPERIMENTAL",
+                "updated": "2013-07-23T11:33:21Z",
+                "links": [
+                    {
+                        "rel": "self",
+                        "href": "http://localhost/v3/",
+                    },
+                ],
+                "links": [
+                    {
+                        "rel": "self",
+                        "href": "http://localhost/v3/",
+                    },
+                    {
+                        "rel": "describedby",
+                        "type": "application/pdf",
+                        "href": EXP_LINKS['v3.0']['pdf'],
+                    },
+                    {
+                        "rel": "describedby",
+                        "type": "application/vnd.sun.wadl+xml",
+                        "href": EXP_LINKS['v3.0']['wadl'],
+                    },
+                ],
+                "media-types": [
+                    {
+                        "base": "application/xml",
+                        "type": "application/"
+                                "vnd.openstack.compute+xml;version=3",
+                    },
+                    {
+                        "base": "application/json",
+                        "type": "application/"
+                                "vnd.openstack.compute+json;version=3",
+                    },
+                ],
+            },
+        }
+        self.assertEqual(expected, version)
+
+    def test_get_version_3_detail_content_type(self):
+        req = webob.Request.blank('/')
+        req.accept = "application/json;version=3"
+        res = req.get_response(fakes.wsgi_app_v3())
+        self.assertEqual(res.status_int, 200)
+        self.assertEqual(res.content_type, "application/json")
+        version = jsonutils.loads(res.body)
+        expected = {
+            "version": {
+                "id": "v3.0",
+                "status": "EXPERIMENTAL",
+                "updated": "2013-07-23T11:33:21Z",
+                "links": [
+                    {
+                        "rel": "self",
+                        "href": "http://localhost/v3/",
+                    },
+                ],
+                "links": [
+                    {
+                        "rel": "self",
+                        "href": "http://localhost/v3/",
+                    },
+                    {
+                        "rel": "describedby",
+                        "type": "application/pdf",
+                        "href": EXP_LINKS['v3.0']['pdf'],
+                    },
+                    {
+                        "rel": "describedby",
+                        "type": "application/vnd.sun.wadl+xml",
+                        "href": EXP_LINKS['v3.0']['wadl'],
+                    },
+                ],
+                "media-types": [
+                    {
+                        "base": "application/xml",
+                        "type": "application/"
+                                "vnd.openstack.compute+xml;version=3",
+                    },
+                    {
+                        "base": "application/json",
+                        "type": "application/"
+                                "vnd.openstack.compute+json;version=3",
+                    },
+                ],
+            },
+        }
+        self.assertEqual(expected, version)
+
+    def test_get_version_3_detail_xml(self):
+        req = webob.Request.blank('/v3/')
+        req.accept = "application/xml"
+        res = req.get_response(fakes.wsgi_app_v3())
+        self.assertEqual(res.status_int, 200)
+        self.assertEqual(res.content_type, "application/xml")
+
+        version = etree.XML(res.body)
+        xmlutil.validate_schema(version, 'version')
+
+        expected = EXP_VERSIONS['v3.0']
+        self.assertTrue(version.xpath('/ns:version', namespaces=NS))
+        media_types = version.xpath('ns:media-types/ns:media-type',
+                                    namespaces=NS)
+        self.assertTrue(common.compare_media_types(media_types,
+                                             expected['media-types']))
+        for key in ['id', 'status', 'updated']:
+            self.assertEqual(version.get(key), expected[key])
+        links = version.xpath('atom:link', namespaces=NS)
+        self.assertTrue(common.compare_links(links,
+            [{'rel': 'self', 'href': 'http://localhost/v3/'}]
+            + expected['links']))
+
+    def test_get_version_3_detail_atom(self):
+        req = webob.Request.blank('/v3/')
+        req.accept = "application/atom+xml"
+        res = req.get_response(fakes.wsgi_app_v3())
+        self.assertEqual(res.status_int, 200)
+        self.assertEqual("application/atom+xml", res.content_type)
+
+        xmlutil.validate_schema(etree.XML(res.body), 'atom')
+
+        f = feedparser.parse(res.body)
+        self.assertEqual(f.feed.title, 'About This Version')
+        self.assertEqual(f.feed.updated, '2013-07-23T11:33:21Z')
+        self.assertEqual(f.feed.id, 'http://localhost/v3/')
+        self.assertEqual(f.feed.author, 'Rackspace')
+        self.assertEqual(f.feed.author_detail.href,
+                         'http://www.rackspace.com/')
+        self.assertEqual(f.feed.links[0]['href'], 'http://localhost/v3/')
+        self.assertEqual(f.feed.links[0]['rel'], 'self')
+
+        self.assertEqual(len(f.entries), 1)
+        entry = f.entries[0]
+        self.assertEqual(entry.id, 'http://localhost/v3/')
+        self.assertEqual(entry.title, 'Version v3.0')
+        self.assertEqual(entry.updated, '2013-07-23T11:33:21Z')
+        self.assertEqual(len(entry.content), 1)
+        self.assertEqual(entry.content[0].value,
+            'Version v3.0 EXPERIMENTAL (2013-07-23T11:33:21Z)')
+        self.assertEqual(len(entry.links), 3)
+        self.assertEqual(entry.links[0]['href'], 'http://localhost/v3/')
+        self.assertEqual(entry.links[0]['rel'], 'self')
+        self.assertEqual(entry.links[1], {
+            'href': EXP_LINKS['v3.0']['pdf'],
+            'type': 'application/pdf',
+            'rel': 'describedby'})
+        self.assertEqual(entry.links[2], {
+            'href': EXP_LINKS['v3.0']['wadl'],
+            'type': 'application/vnd.sun.wadl+xml',
+            'rel': 'describedby'})
--- a/nova/tests/api/openstack/compute/test_versions.py
+++ b/nova/tests/api/openstack/compute/test_versions.py
@ -75,6 +75,21 @@ EXP_VERSIONS = {
            },
        ],
    },
+    "v3.0": {
+        "id": "v3.0",
+        "status": "EXPERIMENTAL",
+        "updated": "2013-07-23T11:33:21Z",
+        "media-types": [
+            {
+                "base": "application/xml",
+                "type": "application/vnd.openstack.compute+xml;version=3",
+            },
+            {
+                "base": "application/json",
+                "type": "application/vnd.openstack.compute+json;version=3",
+            }
+        ],
+    }
 }


@ -98,6 +113,16 @@ class VersionsTest(test.TestCase):
                        "href": "http://localhost/v2/",
                    }],
            },
+            {
+                "id": "v3.0",
+                "status": "EXPERIMENTAL",
+                "updated": "2013-07-23T11:33:21Z",
+                "links": [
+                    {
+                        "rel": "self",
+                        "href": "http://localhost/v3/",
+                    }],
+            },
        ]
        self.assertEqual(versions, expected)

@ -232,9 +257,9 @@ class VersionsTest(test.TestCase):

        self.assertTrue(root.xpath('/ns:versions', namespaces=NS))
        versions = root.xpath('ns:version', namespaces=NS)
-        self.assertEqual(len(versions), 1)
+        self.assertEqual(len(versions), 2)

-        for i, v in enumerate(['v2.0']):
+        for i, v in enumerate(['v2.0', 'v3.0']):
            version = versions[i]
            expected = EXP_VERSIONS[v]
            for key in ['id', 'status', 'updated']:
@ -291,7 +316,7 @@ class VersionsTest(test.TestCase):

        f = feedparser.parse(res.body)
        self.assertEqual(f.feed.title, 'Available API Versions')
-        self.assertEqual(f.feed.updated, '2011-01-21T11:33:21Z')
+        self.assertEqual(f.feed.updated, '2013-07-23T11:33:21Z')
        self.assertEqual(f.feed.id, 'http://localhost/')
        self.assertEqual(f.feed.author, 'Rackspace')
        self.assertEqual(f.feed.author_detail.href,
@ -299,7 +324,7 @@ class VersionsTest(test.TestCase):
        self.assertEqual(f.feed.links[0]['href'], 'http://localhost/')
        self.assertEqual(f.feed.links[0]['rel'], 'self')

-        self.assertEqual(len(f.entries), 1)
+        self.assertEqual(len(f.entries), 2)
        entry = f.entries[0]
        self.assertEqual(entry.id, 'http://localhost/v2/')
        self.assertEqual(entry.title, 'Version v2.0')
@ -311,6 +336,17 @@ class VersionsTest(test.TestCase):
        self.assertEqual(entry.links[0]['href'], 'http://localhost/v2/')
        self.assertEqual(entry.links[0]['rel'], 'self')

+        entry = f.entries[1]
+        self.assertEqual(entry.id, 'http://localhost/v3/')
+        self.assertEqual(entry.title, 'Version v3.0')
+        self.assertEqual(entry.updated, '2013-07-23T11:33:21Z')
+        self.assertEqual(len(entry.content), 1)
+        self.assertEqual(entry.content[0].value,
+            'Version v3.0 EXPERIMENTAL (2013-07-23T11:33:21Z)')
+        self.assertEqual(len(entry.links), 1)
+        self.assertEqual(entry.links[0]['href'], 'http://localhost/v3/')
+        self.assertEqual(entry.links[0]['rel'], 'self')
+
    def test_multi_choice_image(self):
        req = webob.Request.blank('/images/1')
        req.accept = "application/json"
@ -320,6 +356,28 @@ class VersionsTest(test.TestCase):

        expected = {
        "choices": [
+            {
+                "id": "v3.0",
+                "status": "EXPERIMENTAL",
+                "links": [
+                    {
+                        "href": "http://localhost/v3/images/1",
+                        "rel": "self",
+                    },
+                ],
+                "media-types": [
+                    {
+                        "base": "application/xml",
+                        "type":
+                        "application/vnd.openstack.compute+xml;version=3",
+                    },
+                    {
+                        "base": "application/json",
+                        "type":
+                        "application/vnd.openstack.compute+json;version=3",
+                    }
+                ],
+            },
            {
                "id": "v2.0",
                "status": "CURRENT",
@ -357,9 +415,9 @@ class VersionsTest(test.TestCase):
        root = etree.XML(res.body)
        self.assertTrue(root.xpath('/ns:choices', namespaces=NS))
        versions = root.xpath('ns:version', namespaces=NS)
-        self.assertEqual(len(versions), 1)
+        self.assertEqual(len(versions), 2)

-        version = versions[0]
+        version = versions[1]
        self.assertEqual(version.get('id'), 'v2.0')
        self.assertEqual(version.get('status'), 'CURRENT')
        media_types = version.xpath('ns:media-types/ns:media-type',
@ -373,6 +431,20 @@ class VersionsTest(test.TestCase):
        self.assertTrue(common.compare_links(links,
            [{'rel': 'self', 'href': 'http://localhost/v2/images/1'}]))

+        version = versions[0]
+        self.assertEqual(version.get('id'), 'v3.0')
+        self.assertEqual(version.get('status'), 'EXPERIMENTAL')
+        media_types = version.xpath('ns:media-types/ns:media-type',
+                                    namespaces=NS)
+        self.assertTrue(common.
+                        compare_media_types(media_types,
+                                            EXP_VERSIONS['v3.0']['media-types']
+                                            ))
+
+        links = version.xpath('atom:link', namespaces=NS)
+        self.assertTrue(common.compare_links(links,
+            [{'rel': 'self', 'href': 'http://localhost/v3/images/1'}]))
+
    def test_multi_choice_server_atom(self):
        """
        Make sure multi choice responses do not have content-type
@ -394,6 +466,28 @@ class VersionsTest(test.TestCase):

        expected = {
        "choices": [
+            {
+                "id": "v3.0",
+                "status": "EXPERIMENTAL",
+                "links": [
+                    {
+                        "href": "http://localhost/v3/servers/" + uuid,
+                        "rel": "self",
+                    },
+                ],
+                "media-types": [
+                    {
+                        "base": "application/xml",
+                        "type":
+                        "application/vnd.openstack.compute+xml;version=3",
+                    },
+                    {
+                        "base": "application/json",
+                        "type":
+                        "application/vnd.openstack.compute+json;version=3",
+                    }
+                ],
+            },
            {
                "id": "v2.0",
                "status": "CURRENT",
@ -461,7 +555,27 @@ class VersionsViewBuilderTests(test.TestCase):
        expected = "http://example.org/app/v2/"

        builder = views.versions.ViewBuilder(base_url)
-        actual = builder.generate_href()
+        actual = builder.generate_href('v2')
+
+        self.assertEqual(actual, expected)
+
+    def test_generate_href_v3(self):
+        base_url = "http://example.org/app/"
+
+        expected = "http://example.org/app/v3/"
+
+        builder = views.versions.ViewBuilder(base_url)
+        actual = builder.generate_href('v3.0')
+
+        self.assertEqual(actual, expected)
+
+    def test_generate_href_unknown(self):
+        base_url = "http://example.org/app/"
+
+        expected = "http://example.org/app/v2/"
+
+        builder = views.versions.ViewBuilder(base_url)
+        actual = builder.generate_href('foo')

        self.assertEqual(actual, expected)

--- a/nova/tests/integrated/api_samples/versions-get-resp.json.tpl
+++ b/nova/tests/integrated/api_samples/versions-get-resp.json.tpl
@ -4,12 +4,23 @@
            "id": "v2.0",
            "links": [
                {
-                    "href": "%(host)s/v2/",
+                    "href": "http://openstack.example.com/v2/",
                    "rel": "self"
                }
            ],
            "status": "CURRENT",
            "updated": "2011-01-21T11:33:21Z"
+        },
+        {
+            "id": "v3.0",
+            "links": [
+                {
+                    "href": "http://openstack.example.com/v3/",
+                    "rel": "self"
+                }
+            ],
+            "status": "EXPERIMENTAL",
+            "updated": "2013-07-23T11:33:21Z"
        }
    ]
 }
--- a/nova/tests/integrated/api_samples/versions-get-resp.xml.tpl
+++ b/nova/tests/integrated/api_samples/versions-get-resp.xml.tpl
@ -3,4 +3,7 @@
  <version status="CURRENT" updated="2011-01-21T11:33:21Z" id="v2.0">
    <atom:link href="http://openstack.example.com/v2/" rel="self"/>
  </version>
+  <version status="EXPERIMENTAL" updated="2013-07-23T11:33:21Z" id="v3.0">
+    <atom:link href="http://openstack.example.com/v3/" rel="self"/>
+  </version>
 </versions>
--- a/setup.cfg
+++ b/setup.cfg
@ -106,6 +106,7 @@ nova.api.v3.extensions =
    services = nova.api.openstack.compute.plugins.v3.services:Services
    simple_tenant_usage = nova.api.openstack.compute.plugins.v3.simple_tenant_usage:SimpleTenantUsage
    used_limits = nova.api.openstack.compute.plugins.v3.used_limits:UsedLimits
+    versions = nova.api.openstack.compute.plugins.v3.versions:Versions

 nova.api.v3.extensions.server.create =
    availability_zone = nova.api.openstack.compute.plugins.v3.availability_zone:AvailabilityZone