Handle float('inf') in tenant_quota_usages properly

tenant_absolute_limits API wrapper converts -1 (unlimited)
to float('inf'), but tenant_quota_usages() cannot handle this
properly. This is a regression during the quota refactoring work.
This commit changes QuotaUsage.add_quota() to accept float('inf')
as one of unlimited quota value.

Closes-Bug: #1741493
Part of blueprint make-quotas-great-again
Change-Id: Ic6ed00761381d52ee04a15a43ee4fe2a30b9a106

openstack_dashboard/test/unit/usage/test_quotas.py

@@ -68,7 +68,8 @@ class QuotaTests(test.APITestCase):
         return usages
 
     def get_usages_from_limits(self, with_volume=True, with_compute=True,
-                               nova_quotas_enabled=True):
+                               nova_quotas_enabled=True,
+                               unlimited_items=None):
         usages = {}
         if with_compute and nova_quotas_enabled:
             usages.update({
@@ -83,6 +84,10 @@ class QuotaTests(test.APITestCase):
                 'gigabytes': {'available': 600, 'used': 400, 'quota': 1000},
                 'snapshots': {'available': 7, 'used': 3, 'quota': 10},
             })
+        if unlimited_items:
+            for item in unlimited_items:
+                usages[item]['available'] = float('inf')
+                usages[item]['quota'] = float('inf')
         return usages
 
     def assertAvailableQuotasEqual(self, expected_usages, actual_usages):
@@ -130,7 +135,8 @@ class QuotaTests(test.APITestCase):
                         cinder: ('tenant_absolute_limits',
                                  'is_volume_service_enabled')})
     def _test_tenant_quota_usages(self, nova_quotas_enabled=True,
-                                  with_compute=True, with_volume=True):
+                                  with_compute=True, with_volume=True,
+                                  unlimited_items=None):
         tenant_id = '1'
         cinder.is_volume_service_enabled(IsA(http.HttpRequest)).AndReturn(
             with_volume)
@@ -157,7 +163,8 @@ class QuotaTests(test.APITestCase):
         expected_output = self.get_usages_from_limits(
             nova_quotas_enabled=nova_quotas_enabled,
             with_volume=with_volume,
-            with_compute=with_compute)
+            with_compute=with_compute,
+            unlimited_items=unlimited_items)
 
         # Compare internal structure of usages to expected.
         self.assertItemsEqual(expected_output, quota_usages.usages)
@@ -173,6 +180,10 @@ class QuotaTests(test.APITestCase):
                                        with_compute=True,
                                        with_volume=False)
 
+    def test_tenant_quota_usages_with_unlimited(self):
+        self.limits['absolute']['maxTotalInstances'] = float('inf')
+        self._test_tenant_quota_usages(unlimited_items=['instances'])
+
     @override_settings(OPENSTACK_HYPERVISOR_FEATURES={'enable_quotas': False})
     @test.create_stubs({api.base: ('is_service_enabled',),
                         cinder: ('is_volume_service_enabled',)})

openstack_dashboard/usage/quotas.py

@@ -137,7 +137,7 @@ class QuotaUsage(dict):
 
     def add_quota(self, quota):
         """Adds an internal tracking reference for the given quota."""
-        if quota.limit is None or quota.limit == -1:
+        if quota.limit in (None, -1, float('inf')):
             # Handle "unlimited" quotas.
             self.usages[quota.name]['quota'] = float("inf")
             self.usages[quota.name]['available'] = float("inf")