don't report network limits after 2.35

We correctly stopped reporting the limits for things like security
groups and floating ips after mv 2.35. We completely missed that
limits are modified by the used_limits extension, and hilarity
ensued. We were reporting no maxSecurityGroups over the wire, but we
were reporting totalSecurityGroups through the magic of extensions.

Change-Id: I85b2b41d919ed6987d4c9288905ccce49c10c81f
Closes-Bug: #1614133

doc/api_samples/limits/v2.36/limit-get-resp.json

@@ -0,0 +1,21 @@
+{
+    "limits": {
+        "absolute": {
+            "maxImageMeta": 128,
+            "maxPersonality": 5,
+            "maxPersonalitySize": 10240,
+            "maxServerMeta": 128,
+            "maxTotalCores": 20,
+            "maxTotalInstances": 10,
+            "maxTotalKeypairs": 100,
+            "maxTotalRAMSize": 51200,
+            "maxServerGroups": 10,
+            "maxServerGroupMembers": 10,
+            "totalCoresUsed": 0,
+            "totalInstancesUsed": 0,
+            "totalRAMUsed": 0,
+            "totalServerGroupsUsed": 0
+        },
+        "rate": []
+    }
+}

nova/api/openstack/compute/used_limits.py

@@ -14,6 +14,9 @@
 
 import six
 
+from nova.api.openstack import api_version_request
+from nova.api.openstack.api_version_request \
+    import MIN_WITHOUT_PROXY_API_SUPPORT_VERSION
 from nova.api.openstack import extensions
 from nova.api.openstack import wsgi
 from nova.policies import used_limits as ul_policies
@@ -41,14 +44,24 @@ class UsedLimitsController(wsgi.Controller):
         context = req.environ['nova.context']
         project_id = self._project_id(context, req)
         quotas = QUOTAS.get_project_quotas(context, project_id, usages=True)
-        quota_map = {
-            'totalRAMUsed': 'ram',
-            'totalCoresUsed': 'cores',
-            'totalInstancesUsed': 'instances',
-            'totalFloatingIpsUsed': 'floating_ips',
-            'totalSecurityGroupsUsed': 'security_groups',
-            'totalServerGroupsUsed': 'server_groups',
-        }
+        if api_version_request.is_supported(
+                req, min_version=MIN_WITHOUT_PROXY_API_SUPPORT_VERSION):
+            quota_map = {
+                'totalRAMUsed': 'ram',
+                'totalCoresUsed': 'cores',
+                'totalInstancesUsed': 'instances',
+                'totalServerGroupsUsed': 'server_groups',
+            }
+        else:
+            quota_map = {
+                'totalRAMUsed': 'ram',
+                'totalCoresUsed': 'cores',
+                'totalInstancesUsed': 'instances',
+                'totalFloatingIpsUsed': 'floating_ips',
+                'totalSecurityGroupsUsed': 'security_groups',
+                'totalServerGroupsUsed': 'server_groups',
+            }
+
         used_limits = {}
         for display_name, key in six.iteritems(quota_map):
             if key in quotas:

nova/tests/functional/api_sample_tests/api_samples/limits/v2.36/limit-get-resp.json.tpl

@@ -0,0 +1,21 @@
+{
+    "limits": {
+        "absolute": {
+            "maxImageMeta": 128,
+            "maxPersonality": 5,
+            "maxPersonalitySize": 10240,
+            "maxServerMeta": 128,
+            "maxTotalCores": 20,
+            "maxTotalInstances": 10,
+            "maxTotalKeypairs": 100,
+            "maxTotalRAMSize": 51200,
+            "maxServerGroups": 10,
+            "maxServerGroupMembers": 10,
+            "totalCoresUsed": 0,
+            "totalInstancesUsed": 0,
+            "totalRAMUsed": 0,
+            "totalServerGroupsUsed": 0
+        },
+        "rate": []
+    }
+}

nova/tests/functional/api_sample_tests/test_limits.py

@@ -29,3 +29,22 @@ class LimitsSampleJsonTest(api_sample_base.ApiSampleTestBaseV21):
     def test_limits_get(self):
         response = self._do_get('limits')
         self._verify_response(self.template, {}, response, 200)
+
+
+class LimitsV236Test(api_sample_base.ApiSampleTestBaseV21):
+    """Test limits don't return network resources after 2.36.
+
+    We dropped the network API in 2.36, which also means that we
+    shouldn't be returning any limits related to network resources
+    either. This tests a different limits template after that point
+    which does not have these.
+
+    """
+    sample_dir = "limits"
+    microversion = '2.36'
+    scenarios = [('v2_36', {'api_major_version': 'v2.1'})]
+
+    def test_limits_get(self):
+        self.api.microversion = self.microversion
+        response = self._do_get('limits')
+        self._verify_response('limit-get-resp', {}, response, 200)

nova/tests/unit/api/openstack/compute/test_used_limits.py

@@ -16,6 +16,7 @@
 import mock
 import six
 
+from nova.api.openstack import api_version_request
 from nova.api.openstack.compute import used_limits \
         as used_limits_v21
 from nova.api.openstack import wsgi
@@ -30,6 +31,8 @@ class FakeRequest(object):
     def __init__(self, context, reserved=False):
         self.environ = {'nova.context': context}
         self.reserved = reserved
+
+        self.api_version_request = api_version_request.min_api_version()
         self.GET = {'reserved': 1} if reserved else {}