Find the Orphan Volume in k8s cluster

deploy/craned/deployment.yaml

@@ -119,6 +119,10 @@ data:
         acceptedResources:
           - kind: Node
             apiVersion: v1
+      - name: Volumes
+        acceptedResources:
+          - kind: PersistentVolume
+            apiVersion: v1
 ---
 apiVersion: v1
 kind: ConfigMap

pkg/recommendation/framework/context.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
+	"strings"
 	"sync"
 
 	jsonpatch "github.com/evanphx/json-patch"
@@ -178,6 +179,19 @@ func RetrieveScale(ctx *RecommendationContext) error {
 	return nil
 }
 
+func RetrieveVolumes(ctx *RecommendationContext) error {
+	if ctx.Recommendation.Spec.TargetRef.Kind == "PersistentVolume" {
+		volumes, err := utils.GetOrphanVolumes(ctx.Client)
+		if len(volumes) == 0 {
+			return err
+		}
+		str := strings.Join(volumes, ",")
+		ctx.Recommendation.Status.RecommendedValue = str
+		return err
+	}
+	return nil
+}
+
 func RetrievePods(ctx *RecommendationContext) error {
 	if ctx.Recommendation.Spec.TargetRef.Kind == "Node" {
 		pods, err := utils.GetNodePods(ctx.Client, ctx.Recommendation.Spec.TargetRef.Name)

pkg/recommendation/recommender/const.go

@@ -12,4 +12,7 @@ const (
 
 	// IdleNodeRecommender name
 	IdleNodeRecommender string = "IdleNode"
+
+	// VolumesRecommender name
+	VolumesRecommender string = "Volumes"
 )

pkg/recommendation/recommender/volumes/filter.go

@@ -0,0 +1,21 @@
+package volumes
+
+import (
+	"github.com/gocrane/crane/pkg/recommendation/framework"
+)
+
+// Filter out k8s resources that are not supported by the recommender.
+func (vr *VolumesRecommender) Filter(ctx *framework.RecommendationContext) error {
+	var err error
+
+	// filter resource that not match objectIdentity
+	if err = vr.BaseRecommender.Filter(ctx); err != nil {
+		return err
+	}
+
+	if err = framework.RetrieveVolumes(ctx); err != nil {
+		return err
+	}
+
+	return nil
+}

pkg/recommendation/recommender/volumes/observe.go

@@ -0,0 +1,10 @@
+package volumes
+
+import (
+	"github.com/gocrane/crane/pkg/recommendation/framework"
+)
+
+// Observe enhance the observability.
+func (s *VolumesRecommender) Observe(ctx *framework.RecommendationContext) error {
+	return nil
+}

pkg/recommendation/recommender/volumes/prepare.go

@@ -0,0 +1,22 @@
+package volumes
+
+import (
+	"github.com/gocrane/crane/pkg/recommendation/framework"
+)
+
+// CheckDataProviders in PrePrepare phase, will create data source provider via your recommendation config.
+func (rr *VolumesRecommender) CheckDataProviders(ctx *framework.RecommendationContext) error {
+	if err := rr.BaseRecommender.CheckDataProviders(ctx); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (rr *VolumesRecommender) CollectData(ctx *framework.RecommendationContext) error {
+	return nil
+}
+
+func (rr *VolumesRecommender) PostProcessing(ctx *framework.RecommendationContext) error {
+	return nil
+}

pkg/recommendation/recommender/volumes/recommend.go

@@ -0,0 +1,20 @@
+package volumes
+
+import (
+	"github.com/gocrane/crane/pkg/recommendation/framework"
+)
+
+func (s *VolumesRecommender) PreRecommend(ctx *framework.RecommendationContext) error {
+	return nil
+}
+
+func (s *VolumesRecommender) Recommend(ctx *framework.RecommendationContext) error {
+	ctx.Recommendation.Status.Action = "Delete"
+	ctx.Recommendation.Status.Description = "It is an Orphan Volumes"
+	return nil
+}
+
+// Policy add some logic for result of recommend phase.
+func (s *VolumesRecommender) Policy(ctx *framework.RecommendationContext) error {
+	return nil
+}

pkg/recommendation/recommender/volumes/registry.go

@@ -0,0 +1,31 @@
+package volumes
+
+import (
+	analysisv1alph1 "github.com/gocrane/api/analysis/v1alpha1"
+	"github.com/gocrane/crane/pkg/recommendation/config"
+	"github.com/gocrane/crane/pkg/recommendation/recommender"
+	"github.com/gocrane/crane/pkg/recommendation/recommender/apis"
+	"github.com/gocrane/crane/pkg/recommendation/recommender/base"
+)
+
+var _ recommender.Recommender = &VolumesRecommender{}
+
+type VolumesRecommender struct {
+	base.BaseRecommender
+}
+
+func init() {
+	recommender.RegisterRecommenderProvider(recommender.VolumesRecommender, NewVolumesRecommender)
+}
+
+func (s *VolumesRecommender) Name() string {
+	return recommender.VolumesRecommender
+}
+
+// NewVolumesRecommender create a new Volumes recommender.
+func NewVolumesRecommender(recommender apis.Recommender, recommendationRule analysisv1alph1.RecommendationRule) (recommender.Recommender, error) {
+	recommender = config.MergeRecommenderConfigFromRule(recommender, recommendationRule)
+	return &VolumesRecommender{
+		*base.NewBaseRecommender(recommender),
+	}, nil
+}

pkg/utils/pod.go

@@ -312,6 +312,43 @@ func GetNodePods(kubeClient client.Client, nodeName string) ([]corev1.Pod, error
 	return podList.Items, nil
 }
 
+// GetOrphanVolumes returns Orphan Volumes
+func GetOrphanVolumes(kubeClient client.Client) ([]string, error) {
+	// Get a list of all volumes
+	volumes := &corev1.PersistentVolumeList{}
+	if err := kubeClient.List(context.Background(), volumes); err != nil {
+		return nil, err
+	}
+
+	// Get a list of all pods
+	pods := &corev1.PodList{}
+	if err := kubeClient.List(context.Background(), pods); err != nil {
+		return nil, err
+	}
+
+	// Check if each volume is being used by any pods
+	orphanVolumesName := []string{}
+	for _, volume := range volumes.Items {
+		if isOrphanVolume(&volume, pods) {
+			orphanVolumesName = append(orphanVolumesName, volume.Spec.ClaimRef.Name)
+		}
+	}
+
+	return orphanVolumesName, nil
+}
+
+// volume is not being used by any pod
+func isOrphanVolume(volume *corev1.PersistentVolume, pods *corev1.PodList) bool {
+	for _, pod := range pods.Items {
+		for _, volumeClaim := range pod.Spec.Volumes {
+			if volumeClaim.PersistentVolumeClaim != nil && volumeClaim.PersistentVolumeClaim.ClaimName == volume.Spec.ClaimRef.Name {
+				return false
+			}
+		}
+	}
+	return true
+}
+
 func IsPodTerminated(pod *corev1.Pod) bool {
 	return pod.Status.Phase == corev1.PodSucceeded || pod.Status.Phase == corev1.PodFailed
 }