quota: Use neutron quota_details API to retrieve usage

Previously neutron did not provide a way to retrieve resource usage
in a single API, so we need to call list APIs and count the number of
resources. Since Pike release, quota details API is provided and
it returns both quota and usage (used + reserved).

blueprint make-quotas-great-again
Change-Id: I63d0e81654c18f0f235631922d64d1109233fcfa

openstack_dashboard/api/neutron.py

@@ -1445,6 +1445,13 @@ def tenant_quota_update(request, tenant_id, **kwargs):
     return neutronclient(request).update_quota(tenant_id, quotas)
 
 
+@profiler.trace
+def tenant_quota_detail_get(request, tenant_id=None):
+    tenant_id = tenant_id or request.user.tenant_id
+    response = neutronclient(request).get('/quotas/%s/details' % tenant_id)
+    return response['quota']
+
+
 @profiler.trace
 def agent_list(request, **params):
     agents = neutronclient(request).list_agents(**params)

openstack_dashboard/dashboards/project/floating_ips/tests.py

@@ -333,6 +333,8 @@ class FloatingIpViewTests(test.TestCase):
             .AndReturn(True)
         api.neutron.is_router_enabled(IsA(http.HttpRequest)) \
             .AndReturn(True)
+        api.neutron.is_extension_supported(IsA(http.HttpRequest),
+                                           'quota_details').AndReturn(False)
         api.neutron.tenant_quota_get(IsA(http.HttpRequest), self.tenant.id) \
             .AndReturn(self.neutron_quotas.first())
         api.neutron.floating_ip_supported(IsA(http.HttpRequest)) \

openstack_dashboard/test/unit/usage/test_quotas.py

@@ -472,6 +472,8 @@ class QuotaTests(test.APITestCase):
         api.base.is_service_enabled(IsA(http.HttpRequest), 'compute') \
             .MultipleTimes().AndReturn(True)
 
+        api.neutron.is_extension_supported(IsA(http.HttpRequest),
+                                           'quota_details').AndReturn(False)
         api.neutron.tenant_quota_get(IsA(http.HttpRequest), '1') \
             .AndReturn(self.neutron_quotas.first())
         if 'networks' in targets:

openstack_dashboard/usage/quotas.py

@@ -355,6 +355,29 @@ def _get_tenant_network_usages(request, usages, disabled_quotas, tenant_id):
     if not enabled_quotas:
         return
 
+    if neutron.is_extension_supported(request, 'quota_details'):
+        details = neutron.tenant_quota_detail_get(request, tenant_id)
+        for name, neutron_name in (
+                ('floating_ips', 'floatingip'),
+                ('security_groups', 'security_group'),
+                ('security_group_rules', 'security_group_rule'),
+                ('networks', 'network'),
+                ('subnets', 'subnet'),
+                ('ports', 'port'),
+                ('routers', 'router')):
+            if neutron_name in disabled_quotas:
+                continue
+            detail = details[neutron_name]
+            usages.add_quota(base.Quota(name, detail['limit']))
+            usages.tally(name, detail['used'] + detail['reserved'])
+    else:
+        _get_tenant_network_usages_legacy(
+            request, usages, disabled_quotas, tenant_id)
+
+
+def _get_tenant_network_usages_legacy(request, usages, disabled_quotas,
+                                      tenant_id):
+    enabled_quotas = NEUTRON_QUOTA_FIELDS - disabled_quotas
     qs = base.QuotaSet()
     _get_neutron_quota_data(request, qs, disabled_quotas, tenant_id)
     for quota in qs: