feat: add PodDisruptionBudget trackability (#999)

add PDB trackability and unit test

Author: britaniar

go.mod

@@ -30,6 +30,7 @@ require (
 	k8s.io/apimachinery v0.30.3
 	k8s.io/client-go v0.30.3
 	k8s.io/component-base v0.30.2
+	k8s.io/component-helpers v0.28.3
 	k8s.io/klog/v2 v2.130.1
 	k8s.io/metrics v0.25.2
 	k8s.io/utils v0.0.0-20240711033017-18e509b52bc8

pkg/controllers/workapplier/availability_tracker.go

@@ -11,11 +11,13 @@ import (
 
 	appv1 "k8s.io/api/apps/v1"
 	corev1 "k8s.io/api/core/v1"
+	policyv1 "k8s.io/api/policy/v1"
 	apiextensionshelpers "k8s.io/apiextensions-apiserver/pkg/apihelpers"
 	apiextensionsv1 "k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1"
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/component-helpers/apps/poddisruptionbudget"
 	"k8s.io/klog/v2"
 
 	"go.goms.io/fleet/pkg/utils"
@@ -79,6 +81,8 @@ func trackInMemberClusterObjAvailabilityByGVR(
 		return trackServiceAvailability(inMemberClusterObj)
 	case utils.CustomResourceDefinitionGVR:
 		return trackCRDAvailability(inMemberClusterObj)
+	case utils.PodDisruptionBudgetGVR:
+		return trackPDBAvailability(inMemberClusterObj)
 	default:
 		if isDataResource(*gvr) {
 			klog.V(2).InfoS("The object from the member cluster is a data object, consider it to be immediately available",
@@ -218,6 +222,21 @@ func trackCRDAvailability(inMemberClusterObj *unstructured.Unstructured) (Manife
 	return ManifestProcessingAvailabilityResultTypeNotYetAvailable, nil
 }
 
+// trackPDBAvailability tracks the availability of a pod disruption budget in the member cluster
+func trackPDBAvailability(curObj *unstructured.Unstructured) (ManifestProcessingAvailabilityResultType, error) {
+	var pdb policyv1.PodDisruptionBudget
+	if err := runtime.DefaultUnstructuredConverter.FromUnstructured(curObj.Object, &pdb); err != nil {
+		return ManifestProcessingAvailabilityResultTypeFailed, controller.NewUnexpectedBehaviorError(err)
+	}
+	// Check if conditions are up-to-date
+	if poddisruptionbudget.ConditionsAreUpToDate(&pdb) {
+		klog.V(2).InfoS("PodDisruptionBudget is available", "pdb", klog.KObj(curObj))
+		return ManifestProcessingAvailabilityResultTypeAvailable, nil
+	}
+	klog.V(2).InfoS("Still need to wait for PodDisruptionBudget to be available", "pdb", klog.KObj(curObj))
+	return ManifestProcessingAvailabilityResultTypeNotYetAvailable, nil
+}
+
 // isDataResource checks if the resource is a data resource; such resources are
 // available immediately after creation.
 func isDataResource(gvr schema.GroupVersionResource) bool {

pkg/controllers/workapplier/availability_tracker_test.go

@@ -14,10 +14,12 @@ import (
 	appsv1 "k8s.io/api/apps/v1"
 	batchv1 "k8s.io/api/batch/v1"
 	corev1 "k8s.io/api/core/v1"
+	policyv1 "k8s.io/api/policy/v1"
 	apiextensionsv1 "k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/apimachinery/pkg/util/intstr"
 	"k8s.io/klog/v2"
 	"k8s.io/utils/ptr"
 
@@ -136,6 +138,22 @@ var (
 			},
 		},
 	}
+	minAvailable = intstr.FromInt32(1)
+
+	pdbTemplate = &policyv1.PodDisruptionBudget{
+		TypeMeta: metav1.TypeMeta{
+			APIVersion: "policy/v1",
+			Kind:       "PodDisruptionBudget",
+		},
+		ObjectMeta: metav1.ObjectMeta{
+			Name:       "test-pdb",
+			Namespace:  nsName,
+			Generation: 2,
+		},
+		Spec: policyv1.PodDisruptionBudgetSpec{
+			MinAvailable: &minAvailable,
+		},
+	}
 )
 
 // TestTrackDeploymentAvailability tests the trackDeploymentAvailability function.
@@ -667,6 +685,93 @@ func TestTrackCRDAvailability(t *testing.T) {
 	}
 }
 
+// TestTrackPDBAvailability tests the trackPDBAvailability function.
+func TestTrackPDBAvailability(t *testing.T) {
+	availablePDB := pdbTemplate.DeepCopy()
+	availablePDB.Status = policyv1.PodDisruptionBudgetStatus{
+		DisruptionsAllowed: 1,
+		CurrentHealthy:     2,
+		ObservedGeneration: 2,
+		DesiredHealthy:     2,
+		ExpectedPods:       1,
+		Conditions: []metav1.Condition{
+			{
+				Type:               policyv1.DisruptionAllowedCondition,
+				Status:             metav1.ConditionTrue,
+				Reason:             policyv1.SufficientPodsReason,
+				ObservedGeneration: 2,
+			},
+		},
+	}
+	unavailablePDBInsufficientPods := pdbTemplate.DeepCopy()
+	unavailablePDBInsufficientPods.Status = policyv1.PodDisruptionBudgetStatus{
+		DisruptionsAllowed: 0,
+		CurrentHealthy:     1,
+		ObservedGeneration: 2,
+		DesiredHealthy:     2,
+		ExpectedPods:       1,
+		Conditions: []metav1.Condition{
+			{
+				Type:               policyv1.DisruptionAllowedCondition,
+				Status:             metav1.ConditionTrue,
+				Reason:             policyv1.SufficientPodsReason,
+				ObservedGeneration: 2,
+			},
+		},
+	}
+
+	unavailablePDBStaleCondition := pdbTemplate.DeepCopy()
+	unavailablePDBStaleCondition.Status = policyv1.PodDisruptionBudgetStatus{
+		DisruptionsAllowed: 1,
+		CurrentHealthy:     2,
+		ObservedGeneration: 1,
+		DesiredHealthy:     2,
+		ExpectedPods:       1,
+		Conditions: []metav1.Condition{
+			{
+				Type:               policyv1.DisruptionAllowedCondition,
+				Status:             metav1.ConditionTrue,
+				Reason:             policyv1.SufficientPodsReason,
+				ObservedGeneration: 1,
+			},
+		},
+	}
+
+	testCases := []struct {
+		name                                         string
+		pdb                                          *policyv1.PodDisruptionBudget
+		wantManifestProcessingAvailabilityResultType ManifestProcessingAvailabilityResultType
+	}{
+		{
+			name: "available PDB",
+			pdb:  availablePDB,
+			wantManifestProcessingAvailabilityResultType: ManifestProcessingAvailabilityResultTypeAvailable,
+		},
+		{
+			name: "unavailable PDB (insufficient pods)",
+			pdb:  unavailablePDBInsufficientPods,
+			wantManifestProcessingAvailabilityResultType: ManifestProcessingAvailabilityResultTypeNotYetAvailable,
+		},
+		{
+			name: "unavailable PDB (stale condition)",
+			pdb:  unavailablePDBStaleCondition,
+			wantManifestProcessingAvailabilityResultType: ManifestProcessingAvailabilityResultTypeNotYetAvailable,
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			gotResTyp, err := trackPDBAvailability(toUnstructured(t, tc.pdb))
+			if err != nil {
+				t.Fatalf("trackPDBAvailability() = %v, want no error", err)
+			}
+			if gotResTyp != tc.wantManifestProcessingAvailabilityResultType {
+				t.Errorf("manifestProcessingAvailabilityResultType = %v, want %v", gotResTyp, tc.wantManifestProcessingAvailabilityResultType)
+			}
+		})
+	}
+}
+
 // TestTrackInMemberClusterObjAvailabilityByGVR tests the trackInMemberClusterObjAvailabilityByGVR function.
 func TestTrackInMemberClusterObjAvailabilityByGVR(t *testing.T) {
 	availableDeploy := deploy.DeepCopy()

pkg/utils/common.go

@@ -17,6 +17,7 @@ import (
 	batchv1 "k8s.io/api/batch/v1"
 	corev1 "k8s.io/api/core/v1"
 	discoveryv1 "k8s.io/api/discovery/v1"
+	policyv1 "k8s.io/api/policy/v1"
 	rbacv1 "k8s.io/api/rbac/v1"
 	apiextensionsv1 "k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1"
 	"k8s.io/apimachinery/pkg/api/equality"
@@ -263,6 +264,12 @@ var (
 		Kind:    "Pod",
 	}
 
+	PodDisruptionBudgetGVR = schema.GroupVersionResource{
+		Group:    policyv1.GroupName,
+		Version:  policyv1.SchemeGroupVersion.Version,
+		Resource: "poddisruptionbudgets",
+	}
+
 	RoleMetaGVK = metav1.GroupVersionKind{
 		Group:   rbacv1.SchemeGroupVersion.Group,
 		Version: rbacv1.SchemeGroupVersion.Version,