Add PVC support (#37)

README.md

@@ -12,6 +12,7 @@ Supported resources:
 - [x] ConfigMaps (not used in any Pods)
 - [x] Secrets (not used in any Pods or ServiceAccounts)
 - [x] Pods (whose status is not `Running`)
+- [x] PersistentVolumeClaim (not used in any Pods)
 - [ ] PodDisruptionBudgets
 - [ ] HorizontalPodAutoscalers
 

pkg/cmd/determiner.go

@@ -5,30 +5,31 @@ import (
 	"fmt"
 
 	corev1 "k8s.io/api/core/v1"
-	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/cli-runtime/pkg/resource"
 	"k8s.io/client-go/kubernetes"
 )
 
 const (
-	kindConfigMap = "ConfigMap"
-	kindSecret    = "Secret"
-	kindPod       = "Pod"
+	kindConfigMap             = "ConfigMap"
+	kindSecret                = "Secret"
+	kindPod                   = "Pod"
+	kindPersistentVolumeClaim = "PersistentVolumeClaim"
 )
 
 // determiner determines whether a resource should be pruned.
 type determiner struct {
-	usedConfigMaps map[string]struct{} // key=ConfigMap.Name
-	usedSecrets    map[string]struct{} // key=Secret.Name
+	usedConfigMaps             map[string]struct{} // key=ConfigMap.Name
+	usedSecrets                map[string]struct{} // key=Secret.Name
+	usedPersistentVolumeClaims map[string]struct{} // key=PersistentVolumeClaim.Name
 
 	pods []*corev1.Pod
 }
 
 func newDeterminer(clientset *kubernetes.Clientset, r *resource.Result, namespace string) (*determiner, error) {
 	var (
-		pruneConfigMaps bool
-		pruneSecrets    bool
-		prunePods       bool
+		pruneConfigMaps             bool
+		pruneSecrets                bool
+		prunePersistentVolumeClaims bool
 	)
 
 	if err := r.Visit(func(info *resource.Info, err error) error {
@@ -37,8 +38,8 @@ func newDeterminer(clientset *kubernetes.Clientset, r *resource.Result, namespac
 			pruneConfigMaps = true
 		case kindSecret:
 			pruneSecrets = true
-		case kindPod:
-			prunePods = true
+		case kindPersistentVolumeClaim:
+			prunePersistentVolumeClaims = true
 		}
 		return nil
 	}); err != nil {
@@ -49,7 +50,7 @@ func newDeterminer(clientset *kubernetes.Clientset, r *resource.Result, namespac
 
 	ctx := context.Background()
 
-	if pruneConfigMaps || pruneSecrets || prunePods {
+	if pruneConfigMaps || pruneSecrets || prunePersistentVolumeClaims {
 		var err error
 		d.pods, err = listPods(ctx, clientset, namespace)
 		if err != nil {
@@ -69,6 +70,10 @@ func newDeterminer(clientset *kubernetes.Clientset, r *resource.Result, namespac
 		d.usedSecrets = detectUsedSecrets(d.pods, sas)
 	}
 
+	if prunePersistentVolumeClaims {
+		d.usedPersistentVolumeClaims = detectUsedPersistentVolumeClaims(d.pods)
+	}
+
 	return d, nil
 }
 
@@ -85,12 +90,14 @@ func (d *determiner) determinePrune(info *resource.Info) (bool, error) {
 			return true, nil
 		}
 
+	case kindPersistentVolumeClaim:
+		if _, ok := d.usedPersistentVolumeClaims[info.Name]; !ok {
+			return true, nil
+		}
+
 	case kindPod:
-		var pod corev1.Pod
-		if err := runtime.DefaultUnstructuredConverter.FromUnstructured(
-			info.Object.(runtime.Unstructured).UnstructuredContent(),
-			&pod,
-		); err != nil {
+		pod, err := infoToPod(info)
+		if err != nil {
 			return false, err
 		}
 
@@ -184,3 +191,18 @@ func detectUsedSecrets(pods []*corev1.Pod, sas []*corev1.ServiceAccount) map[str
 
 	return usedSecrets
 }
+
+func detectUsedPersistentVolumeClaims(pods []*corev1.Pod) map[string]struct{} {
+	usedPersistentVolumeClaims := make(map[string]struct{})
+
+	for _, pod := range pods {
+		for _, volume := range pod.Spec.Volumes {
+			if volume.PersistentVolumeClaim == nil {
+				continue
+			}
+			usedPersistentVolumeClaims[volume.PersistentVolumeClaim.ClaimName] = struct{}{}
+		}
+	}
+
+	return usedPersistentVolumeClaims
+}

pkg/cmd/determiner_test.go

@@ -9,10 +9,17 @@ import (
 )
 
 func Test_determiner_determinePrune(t *testing.T) {
+	const (
+		fakeConfigMap             = "fake-cm"
+		fakeSecret                = "fake-secret"
+		fakePersistentVolumeClaim = "fake-pvc"
+	)
+
 	type fields struct {
-		usedConfigMaps map[string]struct{}
-		usedSecrets    map[string]struct{}
-		pods           []*corev1.Pod
+		usedConfigMaps        map[string]struct{}
+		usedSecrets           map[string]struct{}
+		usedPersistentVolumes map[string]struct{}
+		pods                  []*corev1.Pod
 	}
 	type args struct {
 		info *resource.Info
@@ -29,7 +36,7 @@ func Test_determiner_determinePrune(t *testing.T) {
 			name: "configmap should be pruned when it is used",
 			fields: fields{
 				usedConfigMaps: map[string]struct{}{
-					"fake-cm": {},
+					fakeConfigMap: {},
 				},
 				pods: []*corev1.Pod{
 					{
@@ -40,7 +47,7 @@ func Test_determiner_determinePrune(t *testing.T) {
 										{
 											ConfigMapRef: &corev1.ConfigMapEnvSource{
 												LocalObjectReference: corev1.LocalObjectReference{
-													Name: "fake-cm",
+													Name: fakeConfigMap,
 												},
 											},
 										},
@@ -58,7 +65,7 @@ func Test_determiner_determinePrune(t *testing.T) {
 							Kind: kindConfigMap,
 						},
 					},
-					Name: "fake-cm",
+					Name: fakeConfigMap,
 				},
 			},
 			want:    false,
@@ -73,7 +80,7 @@ func Test_determiner_determinePrune(t *testing.T) {
 							Kind: kindConfigMap,
 						},
 					},
-					Name: "fake-cm",
+					Name: fakeConfigMap,
 				},
 			},
 			want:    true,
@@ -83,7 +90,7 @@ func Test_determiner_determinePrune(t *testing.T) {
 			name: "secret should be pruned when it is used",
 			fields: fields{
 				usedSecrets: map[string]struct{}{
-					"fake-secret": {},
+					fakeSecret: {},
 				},
 				pods: []*corev1.Pod{
 					{
@@ -94,7 +101,7 @@ func Test_determiner_determinePrune(t *testing.T) {
 										{
 											SecretRef: &corev1.SecretEnvSource{
 												LocalObjectReference: corev1.LocalObjectReference{
-													Name: "fake-secret",
+													Name: fakeSecret,
 												},
 											},
 										},
@@ -112,7 +119,7 @@ func Test_determiner_determinePrune(t *testing.T) {
 							Kind: kindSecret,
 						},
 					},
-					Name: "fake-secret",
+					Name: fakeSecret,
 				},
 			},
 			want:    false,
@@ -127,7 +134,57 @@ func Test_determiner_determinePrune(t *testing.T) {
 							Kind: kindSecret,
 						},
 					},
-					Name: "fake-secret",
+					Name: fakeSecret,
+				},
+			},
+			want:    true,
+			wantErr: false,
+		},
+		{
+			name: "pvc should be pruned when it is used",
+			fields: fields{
+				usedPersistentVolumes: map[string]struct{}{
+					fakePersistentVolumeClaim: {},
+				},
+				pods: []*corev1.Pod{
+					{
+						Spec: corev1.PodSpec{
+							Volumes: []corev1.Volume{
+								{
+									VolumeSource: corev1.VolumeSource{
+										PersistentVolumeClaim: &corev1.PersistentVolumeClaimVolumeSource{
+											ClaimName: fakePersistentVolumeClaim,
+										},
+									},
+								},
+							},
+						},
+					},
+				},
+			},
+			args: args{
+				info: &resource.Info{
+					Object: &corev1.PersistentVolume{
+						TypeMeta: metav1.TypeMeta{
+							Kind: kindPersistentVolumeClaim,
+						},
+					},
+					Name: fakePersistentVolumeClaim,
+				},
+			},
+			want:    false,
+			wantErr: false,
+		},
+		{
+			name: "pvc should not be pruned when it is not used",
+			args: args{
+				info: &resource.Info{
+					Object: &corev1.PersistentVolume{
+						TypeMeta: metav1.TypeMeta{
+							Kind: kindPersistentVolumeClaim,
+						},
+					},
+					Name: fakePersistentVolumeClaim,
 				},
 			},
 			want:    true,
@@ -142,9 +199,10 @@ func Test_determiner_determinePrune(t *testing.T) {
 			t.Parallel()
 
 			d := &determiner{
-				usedConfigMaps: tt.fields.usedConfigMaps,
-				usedSecrets:    tt.fields.usedSecrets,
-				pods:           tt.fields.pods,
+				usedConfigMaps:             tt.fields.usedConfigMaps,
+				usedSecrets:                tt.fields.usedSecrets,
+				usedPersistentVolumeClaims: tt.fields.usedPersistentVolumes,
+				pods:                       tt.fields.pods,
 			}
 
 			got, err := d.determinePrune(tt.args.info)

pkg/cmd/resource.go

@@ -5,6 +5,8 @@ import (
 
 	corev1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/cli-runtime/pkg/resource"
 	"k8s.io/client-go/kubernetes"
 )
 
@@ -38,3 +40,15 @@ func podListToPods(podList *corev1.PodList) []*corev1.Pod {
 	}
 	return pods
 }
+
+func infoToPod(info *resource.Info) (*corev1.Pod, error) {
+	var pod corev1.Pod
+	if err := runtime.DefaultUnstructuredConverter.FromUnstructured(
+		info.Object.(runtime.Unstructured).UnstructuredContent(),
+		&pod,
+	); err != nil {
+		return nil, err
+	}
+
+	return &pod, nil
+}