Add Fleet RollingUpdate strategy params validation (#808)

Need to have only values over 0%, otherwise no rolling update would
occur.

pkg/apis/stable/v1alpha1/fleet.go

@@ -143,12 +143,37 @@ func (f *Fleet) GetGameServerSpec() *GameServerSpec {
 	return &f.Spec.Template.Spec
 }
 
+func (f *Fleet) validateRollingUpdate(value *intstr.IntOrString, causes *[]metav1.StatusCause, parameter string) {
+	r, err := intstr.GetValueFromIntOrPercent(value, 100, true)
+	if value.Type == intstr.String {
+		if err != nil || r < 1 || r > 99 {
+			*causes = append(*causes, metav1.StatusCause{
+				Type:    metav1.CauseTypeFieldValueInvalid,
+				Field:   parameter,
+				Message: parameter + " does not have a valid percentage value (1%-99%)",
+			})
+		}
+	} else {
+		if r < 1 {
+			*causes = append(*causes, metav1.StatusCause{
+				Type:    metav1.CauseTypeFieldValueInvalid,
+				Field:   parameter,
+				Message: parameter + " does not have a valid integer value (>1)",
+			})
+		}
+	}
+}
+
 // Validate validates the Fleet configuration.
 // If a Fleet is invalid there will be > 0 values in
 // the returned array
 func (f *Fleet) Validate() ([]metav1.StatusCause, bool) {
 	causes := validateName(f)
 
+	if f.Spec.Strategy.Type == appsv1.RollingUpdateDeploymentStrategyType {
+		f.validateRollingUpdate(f.Spec.Strategy.RollingUpdate.MaxUnavailable, &causes, "MaxUnavailable")
+		f.validateRollingUpdate(f.Spec.Strategy.RollingUpdate.MaxSurge, &causes, "MaxSurge")
+	}
 	// check Gameserver specification in a Fleet
 	gsCauses := validateGSSpec(f)
 	if len(gsCauses) > 0 {

pkg/apis/stable/v1alpha1/fleet_test.go

@@ -22,6 +22,7 @@ import (
 	appsv1 "k8s.io/api/apps/v1"
 	corev1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/util/intstr"
 	"k8s.io/apimachinery/pkg/util/validation"
 )
 
@@ -102,16 +103,21 @@ func TestSumStatusAllocatedReplicas(t *testing.T) {
 
 func TestFleetGameserverSpec(t *testing.T) {
 	f := defaultFleet()
+	f.ApplyDefaults()
+	causes, ok := f.Validate()
+	assert.True(t, ok)
+	assert.Len(t, causes, 0)
+
 	f.Spec.Template.Spec.Template =
 		corev1.PodTemplateSpec{
 			Spec: corev1.PodSpec{
 				Containers: []corev1.Container{{Name: "container", Image: "myimage"}, {Name: "container2", Image: "myimage"}},
 			},
 		}
-	causes, ok := f.Validate()
+	causes, ok = f.Validate()
 
 	assert.False(t, ok)
-	assert.Len(t, causes, 2)
+	assert.Len(t, causes, 1)
 	assert.Equal(t, "container", causes[0].Field)
 
 	f.Spec.Template.Spec.Container = "testing"
@@ -120,6 +126,33 @@ func TestFleetGameserverSpec(t *testing.T) {
 	assert.False(t, ok)
 	assert.Len(t, causes, 1)
 	assert.Equal(t, "Could not find a container named testing", causes[0].Message)
+
+	f.Spec.Template.Spec.Container = "container"
+	causes, ok = f.Validate()
+	assert.True(t, ok)
+	assert.Len(t, causes, 0)
+
+	// Verify RollingUpdate parameters validation
+	percent := intstr.FromString("0%")
+	f.Spec.Strategy.RollingUpdate.MaxUnavailable = &percent
+	f.Spec.Strategy.RollingUpdate.MaxSurge = &percent
+	causes, ok = f.Validate()
+	assert.False(t, ok)
+	assert.Len(t, causes, 2)
+
+	intParam := intstr.FromInt(0)
+	f.Spec.Strategy.RollingUpdate.MaxUnavailable = &intParam
+	f.Spec.Strategy.RollingUpdate.MaxSurge = &intParam
+	causes, ok = f.Validate()
+	assert.False(t, ok)
+	assert.Len(t, causes, 2)
+
+	percent = intstr.FromString("2a")
+	f.Spec.Strategy.RollingUpdate.MaxUnavailable = &percent
+	f.Spec.Strategy.RollingUpdate.MaxSurge = &percent
+	causes, ok = f.Validate()
+	assert.False(t, ok)
+	assert.Len(t, causes, 2)
 }
 
 func TestFleetName(t *testing.T) {