Support Pagination for namespace list

The rest api metadefs/namespaces supports pagination using the parameters
of limit, marker, sort_dir, & sort_key. However, the glance client isn't
passing those parameters through (they come in as kwargs). This is
preventing pagination from working properly in horizon.

This is affecting Horizon support: https://review.openstack.org/#/c/104063/

Change-Id: Ib349cf3a3a437eb1711f350b37d0bd0e7d01330a
Closes-Bug: 1381816

glanceclient/v2/metadefs.py

@@ -22,6 +22,8 @@ from glanceclient.openstack.common import strutils
 from glanceclient.v2 import schemas
 
 DEFAULT_PAGE_SIZE = 20
+SORT_DIR_VALUES = ('asc', 'desc')
+SORT_KEY_VALUES = ('created_at', 'namespace')
 
 
 class NamespaceController(object):
@@ -88,8 +90,17 @@ class NamespaceController(object):
 
     def list(self, **kwargs):
         """Retrieve a listing of Namespace objects
-
+        :param page_size: Number of items to request in each paginated request
-        :param page_size: Number of namespaces to request in each request
+        :param limit: Use to request a specific page size. Expect a response
+                      to a limited request to return between zero and limit
+                      items.
+        :param marker: Specifies the namespace of the last-seen namespace.
+                       The typical pattern of limit and marker is to make an
+                       initial limited request and then to use the last
+                       namespace from the response as the marker parameter
+                       in a subsequent limited request.
+        :param sort_key: The field to sort on (for example, 'created_at')
+        :param sort_dir: The direction to sort ('asc' or 'desc')
         :returns generator over list of Namespaces
         """
 
@@ -129,6 +140,25 @@ class NamespaceController(object):
         else:
             filters['limit'] = kwargs['page_size']
 
+        if 'marker' in kwargs:
+            filters['marker'] = kwargs['marker']
+
+        sort_key = kwargs.get('sort_key')
+        if sort_key is not None:
+            if sort_key in SORT_KEY_VALUES:
+                filters['sort_key'] = sort_key
+            else:
+                raise ValueError('sort_key must be one of the following: %s.'
+                                 % ', '.join(SORT_KEY_VALUES))
+
+        sort_dir = kwargs.get('sort_dir')
+        if sort_dir is not None:
+            if sort_dir in SORT_DIR_VALUES:
+                filters['sort_dir'] = sort_dir
+            else:
+                raise ValueError('sort_dir must be one of the following: %s.'
+                                 % ', '.join(SORT_DIR_VALUES))
+
         for param, value in six.iteritems(filters):
             if isinstance(value, list):
                 filters[param] = strutils.safe_encode(','.join(value))

tests/v2/test_metadefs_namespaces.py

@@ -89,7 +89,7 @@ data_fixtures = {
         "GET": (
             {},
             {
-                "first": "/v2/metadefs/namespaces?limit=1",
+                "first": "/v2/metadefs/namespaces?limit=2",
                 "namespaces": [
                     _get_namespace_fixture(NAMESPACE8),
                 ],
@@ -97,6 +97,43 @@ data_fixtures = {
             }
         )
     },
+    "/v2/metadefs/namespaces?limit=2&marker=%s" % NAMESPACE6: {
+        "GET": (
+            {},
+            {
+                "first": "/v2/metadefs/namespaces?limit=2",
+                "namespaces": [
+                    _get_namespace_fixture(NAMESPACE7),
+                    _get_namespace_fixture(NAMESPACE8),
+                ],
+                "schema": "/v2/schemas/metadefs/namespaces"
+            }
+        )
+    },
+    "/v2/metadefs/namespaces?limit=20&sort_dir=asc": {
+        "GET": (
+            {},
+            {
+                "first": "/v2/metadefs/namespaces?limit=1",
+                "namespaces": [
+                    _get_namespace_fixture(NAMESPACE1),
+                ],
+                "schema": "/v2/schemas/metadefs/namespaces"
+            }
+        )
+    },
+    "/v2/metadefs/namespaces?limit=20&sort_key=created_at": {
+        "GET": (
+            {},
+            {
+                "first": "/v2/metadefs/namespaces?limit=1",
+                "namespaces": [
+                    _get_namespace_fixture(NAMESPACE1),
+                ],
+                "schema": "/v2/schemas/metadefs/namespaces"
+            }
+        )
+    },
     "/v2/metadefs/namespaces?limit=20&resource_types=%s" % RESOURCE_TYPE1: {
         "GET": (
             {},
@@ -269,7 +306,7 @@ data_fixtures = {
                 "updated_at": "2014-08-14T09:07:06Z",
             }
         ),
-    }
+    },
 }
 
 schema_fixtures = {
@@ -521,6 +558,40 @@ class TestNamespaceController(testtools.TestCase):
         self.assertEqual(NAMESPACE7, namespaces[0]['namespace'])
         self.assertEqual(NAMESPACE8, namespaces[1]['namespace'])
 
+    def test_list_with_limit_greater_than_page_size(self):
+        namespaces = list(self.controller.list(page_size=1, limit=2))
+        self.assertEqual(2, len(namespaces))
+        self.assertEqual(NAMESPACE7, namespaces[0]['namespace'])
+        self.assertEqual(NAMESPACE8, namespaces[1]['namespace'])
+
+    def test_list_with_marker(self):
+        namespaces = list(self.controller.list(marker=NAMESPACE6, page_size=2))
+        self.assertEqual(2, len(namespaces))
+        self.assertEqual(NAMESPACE7, namespaces[0]['namespace'])
+        self.assertEqual(NAMESPACE8, namespaces[1]['namespace'])
+
+    def test_list_with_sort_dir(self):
+        namespaces = list(self.controller.list(sort_dir='asc', limit=1))
+        self.assertEqual(1, len(namespaces))
+        self.assertEqual(NAMESPACE1, namespaces[0]['namespace'])
+
+    def test_list_with_sort_dir_invalid(self):
+        # NOTE(TravT): The clients work by returning an iterator.
+        # Invoking the iterator is what actually executes the logic.
+        ns_iterator = self.controller.list(sort_dir='foo')
+        self.assertRaises(ValueError, next, ns_iterator)
+
+    def test_list_with_sort_key(self):
+        namespaces = list(self.controller.list(sort_key='created_at', limit=1))
+        self.assertEqual(1, len(namespaces))
+        self.assertEqual(NAMESPACE1, namespaces[0]['namespace'])
+
+    def test_list_with_sort_key_invalid(self):
+        # NOTE(TravT): The clients work by returning an iterator.
+        # Invoking the iterator is what actually executes the logic.
+        ns_iterator = self.controller.list(sort_key='foo')
+        self.assertRaises(ValueError, next, ns_iterator)
+
     def test_list_namespaces_with_one_resource_type_filter(self):
         namespaces = list(self.controller.list(
             filters={