Merge lp:~gundlach/nova/rsapi-pagination into lp:~hudson-openstack/nova/trunk

[Michael Gundlach]

Support the pagination interface in RS API -- the &offset and &limit parameters are now recognized.

This implementation is stupid (it just slices the full list at the last second), so in Bexar we should do this right.

[Matt Dietz (cerberus)]

Seems fine

review: Approve

[OpenStack Infra (hudson-openstack)]

Attempt to merge lp:~gundlach/nova/rsapi-pagination into lp:nova failed due to merge conflicts:

text conflict in nova/api/rackspace/flavors.py

=== modified file 'nova/api/rackspace/__init__.py'
--- nova/api/rackspace/__init__.py	2010-09-29 13:39:24 +0000
+++ nova/api/rackspace/__init__.py	2010-09-29 16:37:07 +0000
@@ -168,3 +168,23 @@
                         controller=sharedipgroups.Controller())
 
         super(APIRouter, self).__init__(mapper)
+
+
+def limited(items, req):
+    """Return a slice of items according to requested offset and limit.
+    
+    items - a sliceable
+    req - wobob.Request possibly containing offset and limit GET variables.
+          offset is where to start in the list, and limit is the maximum number
+          of items to return.
+
+    If limit is not specified, 0, or > 1000, defaults to 1000.
+    """
+    offset = int(req.GET.get('offset', 0))
+    limit = int(req.GET.get('limit', 0))
+    if not limit:
+        limit = 1000
+    limit = min(1000, limit)
+    range_end = offset + limit
+    return items[offset:range_end]
+

=== modified file 'nova/api/rackspace/flavors.py'
--- nova/api/rackspace/flavors.py	2010-09-29 13:39:24 +0000
+++ nova/api/rackspace/flavors.py	2010-09-29 16:37:07 +0000
@@ -15,10 +15,12 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+from webob import exc
+
 from nova.api.rackspace import faults
 from nova.compute import instance_types
 from nova import wsgi
-from webob import exc
+import nova.api.rackspace
 
 class Controller(wsgi.Controller):
     """Flavor controller for the Rackspace API."""
@@ -39,6 +41,7 @@
     def detail(self, req):
         """Return all flavors in detail."""
         items = [self.show(req, id)['flavor'] for id in self._all_ids()]
+        items = nova.api.rackspace.limited(items, req)
         return dict(flavors=items)
 
     def show(self, req, id):

=== modified file 'nova/api/rackspace/images.py'
--- nova/api/rackspace/images.py	2010-09-29 13:39:24 +0000
+++ nova/api/rackspace/images.py	2010-09-29 16:37:07 +0000
@@ -19,6 +19,7 @@
 
 from nova import wsgi
 from nova.api.rackspace import _id_translator
+import nova.api.rackspace
 import nova.image.service
 from nova.api.rackspace import faults
 
@@ -46,6 +47,7 @@
     def detail(self, req):
         """Return all public images in detail."""
         data = self._service.index()
+        data = nova.api.rackspace.limited(data, req)
         for img in data:
             img['id'] = self._id_translator.to_rs_id(img['id'])
         return dict(images=data)

=== modified file 'nova/api/rackspace/servers.py'
--- nova/api/rackspace/servers.py	2010-09-29 14:17:10 +0000
+++ nova/api/rackspace/servers.py	2010-09-29 16:37:07 +0000
@@ -26,6 +26,7 @@
 from nova.api.rackspace import _id_translator
 from nova.api.rackspace import faults
 from nova.compute import power_state
+import nova.api.rackspace
 import nova.image.service
 
 FLAGS = flags.FLAGS
@@ -102,16 +103,21 @@
 
     def index(self, req):
         """ Returns a list of server names and ids for a given user """
-        user_id = req.environ['nova.context']['user']['id']
-        instance_list = self.db_driver.instance_get_all_by_user(None, user_id)
-        res = [_entity_inst(inst)['server'] for inst in instance_list]
-        return _entity_list(res)
+        return self._items(req, entity_maker=_entity_inst)
 
     def detail(self, req):
         """ Returns a list of server details for a given user """
+        return self._items(req, entity_maker=_entity_detail)
+
+    def _items(self, req, entity_maker):
+        """Returns a list of servers for a given user.
+
+        entity_maker - either _entity_detail or _entity_inst
+        """
         user_id = req.environ['nova.context']['user']['id']
-        res = [_entity_detail(inst)['server'] for inst in 
-                self.db_driver.instance_get_all_by_user(None, user_id)]
+        instance_list = self.db_driver.instance_get_all_by_user(None, user_id)
+        limited_list = nova.api.rackspace.limited(instance_list, req)
+        res = [entity_maker(inst)['server'] for inst in limited_list]
         return _entity_list(res)
 
     def show(self, req, id):

=== modified file 'nova/tests/api/rackspace/__init__.py'
--- nova/tests/api/rackspace/__init__.py	2010-09-15 17:54:38 +0000
+++ nova/tests/api/rackspace/__init__.py	2010-09-29 16:37:07 +0000
@@ -17,6 +17,7 @@
 
 import unittest
 
+from nova.api.rackspace import limited
 from nova.api.rackspace import RateLimitingMiddleware
 from nova.tests.api.test_helper import *
 from webob import Request
@@ -77,3 +78,31 @@
         self.assertEqual(middleware.limiter.__class__.__name__, "Limiter")
         middleware = RateLimitingMiddleware(APIStub(), service_host='foobar')
         self.assertEqual(middleware.limiter.__class__.__name__, "WSGIAppProxy")
+
+
+class LimiterTest(unittest.TestCase):
+
+    def testLimiter(self):
+        items = range(2000)
+        req = Request.blank('/')
+        self.assertEqual(limited(items, req), items[ :1000])
+        req = Request.blank('/?offset=0')
+        self.assertEqual(limited(items, req), items[ :1000])
+        req = Request.blank('/?offset=3')
+        self.assertEqual(limited(items, req), items[3:1003])
+        req = Request.blank('/?offset=2005')
+        self.assertEqual(limited(items, req), [])
+        req = Request.blank('/?limit=10')
+        self.assertEqual(limited(items, req), items[ :10])
+        req = Request.blank('/?limit=0')
+        self.assertEqual(limited(items, req), items[ :1000])
+        req = Request.blank('/?limit=3000')
+        self.assertEqual(limited(items, req), items[ :1000])
+        req = Request.blank('/?offset=1&limit=3')
+        self.assertEqual(limited(items, req), items[1:4])
+        req = Request.blank('/?offset=3&limit=0')
+        self.assertEqual(limited(items, req), items[3:1003])
+        req = Request.blank('/?offset=3&limit=1500')
+        self.assertEqual(limited(items, req), items[3:1003])
+        req = Request.blank('/?offset=3000&limit=10')
+        self.assertEqual(limited(items, req), [])