Merge pull request #85571 from mgugino-upstream-stage/drain-ignore-pdbs

kubectl/drain: add disable-eviction option

staging/src/k8s.io/kubectl/pkg/cmd/drain/drain.go

@@ -192,6 +192,7 @@ func NewCmdDrain(f cmdutil.Factory, ioStreams genericclioptions.IOStreams) *cobr
 	cmd.Flags().DurationVar(&o.drainer.Timeout, "timeout", o.drainer.Timeout, "The length of time to wait before giving up, zero means infinite")
 	cmd.Flags().StringVarP(&o.drainer.Selector, "selector", "l", o.drainer.Selector, "Selector (label query) to filter on")
 	cmd.Flags().StringVarP(&o.drainer.PodSelector, "pod-selector", "", o.drainer.PodSelector, "Label selector to filter pods on the node")
+	cmd.Flags().BoolVar(&o.drainer.DisableEviction, "disable-eviction", o.drainer.DisableEviction, "Force drain to use delete, even if eviction is supported. This will bypass checking PodDisruptionBudgets, use with caution.")
 
 	cmdutil.AddDryRunFlag(cmd)
 	return cmd

staging/src/k8s.io/kubectl/pkg/drain/drain.go

@@ -52,6 +52,10 @@ type Helper struct {
 	DeleteLocalData     bool
 	Selector            string
 	PodSelector         string
+
+	// DisableEviction forces drain to use delete rather than evict
+	DisableEviction bool
+
 	Out    io.Writer
 	ErrOut io.Writer
 
@@ -179,18 +183,21 @@ func (d *Helper) DeleteOrEvictPods(pods []corev1.Pod) error {
 		return nil
 	}
 
+	// TODO(justinsb): unnecessary?
+	getPodFn := func(namespace, name string) (*corev1.Pod, error) {
+		return d.Client.CoreV1().Pods(namespace).Get(name, metav1.GetOptions{})
+	}
+
+	if !d.DisableEviction {
 		policyGroupVersion, err := CheckEvictionSupport(d.Client)
 		if err != nil {
 			return err
 		}
 
-	// TODO(justinsb): unnecessary?
-	getPodFn := func(namespace, name string) (*corev1.Pod, error) {
-		return d.Client.CoreV1().Pods(namespace).Get(name, metav1.GetOptions{})
-	}
 		if len(policyGroupVersion) > 0 {
 			return d.evictPods(pods, policyGroupVersion, getPodFn)
 		}
+	}
 
 	return d.deletePods(pods, getPodFn)
 }

staging/src/k8s.io/kubectl/pkg/drain/drain_test.go

@@ -245,10 +245,34 @@ func TestCheckEvictionSupport(t *testing.T) {
 }
 
 func TestDeleteOrEvict(t *testing.T) {
-	for _, evictionSupported := range []bool{true, false} {
-		evictionSupported := evictionSupported
-		t.Run(fmt.Sprintf("evictionSupported=%v", evictionSupported),
-			func(t *testing.T) {
+	tests := []struct {
+		description       string
+		evictionSupported bool
+		disableEviction   bool
+	}{
+		{
+			description:       "eviction supported/enabled",
+			evictionSupported: true,
+			disableEviction:   false,
+		},
+		{
+			description:       "eviction unsupported/disabled",
+			evictionSupported: false,
+			disableEviction:   false,
+		},
+		{
+			description:       "eviction supported/disabled",
+			evictionSupported: true,
+			disableEviction:   true,
+		},
+		{
+			description:       "eviction unsupported/disabled",
+			evictionSupported: false,
+			disableEviction:   false,
+		},
+	}
+	for _, tc := range tests {
+		t.Run(tc.description, func(t *testing.T) {
 			h := &Helper{
 				Out:                os.Stdout,
 				GracePeriodSeconds: 10,
@@ -267,7 +291,7 @@ func TestDeleteOrEvict(t *testing.T) {
 				if i <= 2 {
 					deletePods = append(deletePods, *pod)
 
-						if evictionSupported {
+					if tc.evictionSupported && !tc.disableEviction {
 						eviction := policyv1beta1.Eviction{}
 						eviction.Kind = "Eviction"
 						eviction.APIVersion = "policy/v1"
@@ -286,11 +310,11 @@ func TestDeleteOrEvict(t *testing.T) {
 
 			// Build the fake client
 			k := fake.NewSimpleClientset(create...)
-				if evictionSupported {
+			if tc.evictionSupported {
 				addEvictionSupport(t, k)
 			}
 			h.Client = k
-
+			h.DisableEviction = tc.disableEviction
 			// Do the eviction
 			if err := h.DeleteOrEvictPods(deletePods); err != nil {
 				t.Fatalf("error from DeleteOrEvictPods: %v", err)
@@ -311,7 +335,7 @@ func TestDeleteOrEvict(t *testing.T) {
 			}
 			expected := []string{"default/mypod-3", "default/mypod-4"}
 			if !reflect.DeepEqual(remainingPods, expected) {
-					t.Errorf("unexpected remaining pods after DeleteOrEvictPods; actual %v; expected %v", remainingPods, expected)
+				t.Errorf("%s: unexpected remaining pods after DeleteOrEvictPods; actual %v; expected %v", tc.description, remainingPods, expected)
 			}
 
 			// Test that pods were evicted as expected
@@ -327,7 +351,7 @@ func TestDeleteOrEvict(t *testing.T) {
 				return actualEvictions[i].Name < actualEvictions[j].Name
 			})
 			if !reflect.DeepEqual(actualEvictions, expectedEvictions) {
-					t.Errorf("unexpected evictions; actual %v; expected %v", actualEvictions, expectedEvictions)
+				t.Errorf("%s: unexpected evictions; actual %v; expected %v", tc.description, actualEvictions, expectedEvictions)
 			}
 		})
 	}