From 4371509084c97072cc5f2fe16fe01f09b81b1af0 Mon Sep 17 00:00:00 2001
From: Eoghan Glynn <eglynn@redhat.com>
Date: Mon, 10 Dec 2012 19:18:50 +0000
Subject: Consider reserved count in os-user-limits extension

Fixes bug 1088606

Previously, the reserved count was not considered in the
total<Resource>Used values returned, leading to a potentially
inaccurate view of the actual headroom available when resource
creation was in-flight.

Now, the reserved count is optionally included, controlled
by a new 'reserved' query parameter.

Change-Id: If71ac6f8e428b58b7c80c67ad99124e4233102d1
---
 nova/api/openstack/compute/contrib/used_limits.py  | 11 +++++++-
 .../openstack/compute/contrib/test_used_limits.py  | 33 ++++++++++++++++------
 2 files changed, 34 insertions(+), 10 deletions(-)

diff --git a/nova/api/openstack/compute/contrib/used_limits.py b/nova/api/openstack/compute/contrib/used_limits.py
index 020f6d8e4..a7ac33ae9 100644
--- a/nova/api/openstack/compute/contrib/used_limits.py
+++ b/nova/api/openstack/compute/contrib/used_limits.py
@@ -39,6 +39,13 @@ class UsedLimitsTemplate(xmlutil.TemplateBuilder):
 
 class UsedLimitsController(wsgi.Controller):
 
+    @staticmethod
+    def _reserved(req):
+        try:
+            return int(req.GET['reserved'])
+        except (ValueError, KeyError):
+            return False
+
     @wsgi.extends
     def index(self, req, resp_obj):
         resp_obj.attach(xml=UsedLimitsTemplate())
@@ -57,7 +64,9 @@ class UsedLimitsController(wsgi.Controller):
         used_limits = {}
         for display_name, quota in quota_map.iteritems():
             if quota in quotas:
-                used_limits[display_name] = quotas[quota]['in_use']
+                reserved = (quotas[quota]['reserved']
+                            if self._reserved(req) else 0)
+                used_limits[display_name] = quotas[quota]['in_use'] + reserved
 
         resp_obj.obj['limits']['absolute'].update(used_limits)
 
diff --git a/nova/tests/api/openstack/compute/contrib/test_used_limits.py b/nova/tests/api/openstack/compute/contrib/test_used_limits.py
index 3ab814ebb..4a75961ed 100644
--- a/nova/tests/api/openstack/compute/contrib/test_used_limits.py
+++ b/nova/tests/api/openstack/compute/contrib/test_used_limits.py
@@ -24,8 +24,10 @@ from nova import test
 
 
 class FakeRequest(object):
-    def __init__(self, context):
+    def __init__(self, context, reserved=False):
         self.environ = {'nova.context': context}
+        self.reserved = reserved
+        self.GET = {'reserved': 1} if reserved else {}
 
 
 class UsedLimitsTestCase(test.TestCase):
@@ -36,9 +38,9 @@ class UsedLimitsTestCase(test.TestCase):
         self.controller = used_limits.UsedLimitsController()
 
         self.fake_context = nova.context.RequestContext('fake', 'fake')
-        self.fake_req = FakeRequest(self.fake_context)
 
-    def test_used_limits(self):
+    def _do_test_used_limits(self, reserved):
+        fake_req = FakeRequest(self.fake_context, reserved=reserved)
         obj = {
             "limits": {
                 "rate": [],
@@ -57,19 +59,30 @@ class UsedLimitsTestCase(test.TestCase):
         }
         limits = {}
         for display_name, q in quota_map.iteritems():
-            limits[q] = {'limit': 10, 'in_use': 2}
+            limits[q] = {'limit': len(display_name),
+                         'in_use': len(display_name) / 2,
+                         'reserved': len(display_name) / 3}
 
         def stub_get_project_quotas(context, project_id, usages=True):
             return limits
         self.stubs.Set(quota.QUOTAS, "get_project_quotas",
                        stub_get_project_quotas)
 
-        self.controller.index(self.fake_req, res)
+        self.controller.index(fake_req, res)
         abs_limits = res.obj['limits']['absolute']
         for used_limit, value in abs_limits.iteritems():
-            self.assertEqual(value, limits[quota_map[used_limit]]['in_use'])
+            r = limits[quota_map[used_limit]]['reserved'] if reserved else 0
+            self.assertEqual(value,
+                             limits[quota_map[used_limit]]['in_use'] + r)
+
+    def test_used_limits_basic(self):
+        self._do_test_used_limits(False)
+
+    def test_used_limits_with_reserved(self):
+        self._do_test_used_limits(True)
 
     def test_used_ram_added(self):
+        fake_req = FakeRequest(self.fake_context)
         obj = {
             "limits": {
                 "rate": [],
@@ -84,12 +97,13 @@ class UsedLimitsTestCase(test.TestCase):
             return {'ram': {'limit': 512, 'in_use': 256}}
         self.stubs.Set(quota.QUOTAS, "get_project_quotas",
                        stub_get_project_quotas)
-        self.controller.index(self.fake_req, res)
+        self.controller.index(fake_req, res)
         abs_limits = res.obj['limits']['absolute']
         self.assertTrue('totalRAMUsed' in abs_limits)
         self.assertEqual(abs_limits['totalRAMUsed'], 256)
 
     def test_no_ram_quota(self):
+        fake_req = FakeRequest(self.fake_context)
         obj = {
             "limits": {
                 "rate": [],
@@ -102,11 +116,12 @@ class UsedLimitsTestCase(test.TestCase):
             return {}
         self.stubs.Set(quota.QUOTAS, "get_project_quotas",
                        stub_get_project_quotas)
-        self.controller.index(self.fake_req, res)
+        self.controller.index(fake_req, res)
         abs_limits = res.obj['limits']['absolute']
         self.assertFalse('totalRAMUsed' in abs_limits)
 
     def test_used_limits_xmlns(self):
+        fake_req = FakeRequest(self.fake_context)
         obj = {
             "limits": {
                 "rate": [],
@@ -120,6 +135,6 @@ class UsedLimitsTestCase(test.TestCase):
             return {}
         self.stubs.Set(quota.QUOTAS, "get_project_quotas",
                        stub_get_project_quotas)
-        self.controller.index(self.fake_req, res)
+        self.controller.index(fake_req, res)
         response = res.serialize(None, 'xml')
         self.assertTrue(used_limits.XMLNS in response.body)
-- 
cgit