fix: Ensure that resource limits that exactly equal capacity are allo…

…wed (#200)

* Ensure that resource limits that exactly equal capacity are allowed

Change the definition of ExceededBy to allow exact resource
matches (this can happen if a Provisioner has
`spec.resources.limits.cpu` set to a value identical to a node's
CPU count (or a multiple of a node's CPU count))

* Add test case for limits ExceededBy method

pkg/apis/v1alpha5/limits.go

@@ -32,7 +32,7 @@ func (l *Limits) ExceededBy(resources v1.ResourceList) error {
 	}
 	for resourceName, usage := range resources {
 		if limit, ok := l.Resources[resourceName]; ok {
-			if usage.Cmp(limit) >= 0 {
+			if usage.Cmp(limit) > 0 {
 				return fmt.Errorf("%s resource usage of %v exceeds limit of %v", resourceName, usage.AsDec(), limit.AsDec())
 			}
 		}

pkg/apis/v1alpha5/suite_test.go

@@ -482,3 +482,33 @@ var _ = Describe("Validation", func() {
 		})
 	})
 })
+
+var _ = Describe("Limits", func() {
+	var provisioner *Provisioner
+
+	BeforeEach(func() {
+		provisioner = &Provisioner{
+			ObjectMeta: metav1.ObjectMeta{Name: strings.ToLower(randomdata.SillyName())},
+			Spec: ProvisionerSpec{
+				Limits: &Limits{
+					Resources: v1.ResourceList{
+						"cpu": resource.MustParse("16"),
+					},
+				},
+			},
+		}
+	})
+
+	It("should work when usage is lower than limit", func() {
+		provisioner.Status.Resources = v1.ResourceList{"cpu": resource.MustParse("15")}
+		Expect(provisioner.Spec.Limits.ExceededBy(provisioner.Status.Resources)).To(Succeed())
+	})
+	It("should work when usage is equal to limit", func() {
+		provisioner.Status.Resources = v1.ResourceList{"cpu": resource.MustParse("16")}
+		Expect(provisioner.Spec.Limits.ExceededBy(provisioner.Status.Resources)).To(Succeed())
+	})
+	It("should fail when usage is higher than limit", func() {
+		provisioner.Status.Resources = v1.ResourceList{"cpu": resource.MustParse("17")}
+		Expect(provisioner.Spec.Limits.ExceededBy(provisioner.Status.Resources)).To(MatchError("cpu resource usage of 17 exceeds limit of 16"))
+	})
+})