Merge pull request #102155 from lauchokyip/addTop

Added field-selector option for kubectl top pod

staging/src/k8s.io/kubectl/pkg/cmd/top/top_pod.go

@@ -24,6 +24,7 @@ import (
 
 	"k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/fields"
 	"k8s.io/apimachinery/pkg/labels"
 	"k8s.io/client-go/discovery"
 	corev1client "k8s.io/client-go/kubernetes/typed/core/v1"
@@ -44,7 +45,8 @@ import (
 type TopPodOptions struct {
 	ResourceName       string
 	Namespace          string
-	Selector           string
+	LabelSelector      string
+	FieldSelector      string
 	SortBy             string
 	AllNamespaces      bool
 	PrintContainers    bool
@@ -106,7 +108,8 @@ func NewCmdTopPod(f cmdutil.Factory, o *TopPodOptions, streams genericclioptions
 		},
 		Aliases: []string{"pods", "po"},
 	}
-	cmd.Flags().StringVarP(&o.Selector, "selector", "l", o.Selector, "Selector (label query) to filter on, supports '=', '==', and '!='.(e.g. -l key1=value1,key2=value2)")
+	cmd.Flags().StringVarP(&o.LabelSelector, "selector", "l", o.LabelSelector, "Selector (label query) to filter on, supports '=', '==', and '!='.(e.g. -l key1=value1,key2=value2)")
+	cmd.Flags().StringVar(&o.FieldSelector, "field-selector", o.FieldSelector, "Selector (field query) to filter on, supports '=', '==', and '!='.(e.g. --field-selector key1=value1,key2=value2). The server only supports a limited number of field queries per type.")
 	cmd.Flags().StringVar(&o.SortBy, "sort-by", o.SortBy, "If non-empty, sort pods list using specified field. The field can be either 'cpu' or 'memory'.")
 	cmd.Flags().BoolVar(&o.PrintContainers, "containers", o.PrintContainers, "If present, print usage of containers within a pod.")
 	cmd.Flags().BoolVarP(&o.AllNamespaces, "all-namespaces", "A", o.AllNamespaces, "If present, list the requested object(s) across all namespaces. Namespace in current context is ignored even if specified with --namespace.")
@@ -157,17 +160,24 @@ func (o *TopPodOptions) Validate() error {
 			return errors.New("--sort-by accepts only cpu or memory")
 		}
 	}
-	if len(o.ResourceName) > 0 && len(o.Selector) > 0 {
+	if len(o.ResourceName) > 0 && (len(o.LabelSelector) > 0 || len(o.FieldSelector) > 0) {
-		return errors.New("only one of NAME or --selector can be provided")
+		return errors.New("only one of NAME or selector can be provided")
 	}
 	return nil
 }
 
 func (o TopPodOptions) RunTopPod() error {
 	var err error
-	selector := labels.Everything()
+	labelSelector := labels.Everything()
-	if len(o.Selector) > 0 {
+	if len(o.LabelSelector) > 0 {
-		selector, err = labels.Parse(o.Selector)
+		labelSelector, err = labels.Parse(o.LabelSelector)
+		if err != nil {
+			return err
+		}
+	}
+	fieldSelector := fields.Everything()
+	if len(o.FieldSelector) > 0 {
+		fieldSelector, err = fields.ParseSelector(o.FieldSelector)
 		if err != nil {
 			return err
 		}
@@ -183,7 +193,7 @@ func (o TopPodOptions) RunTopPod() error {
 	if !metricsAPIAvailable {
 		return errors.New("Metrics API not available")
 	}
-	metrics, err := getMetricsFromMetricsAPI(o.MetricsClient, o.Namespace, o.ResourceName, o.AllNamespaces, selector)
+	metrics, err := getMetricsFromMetricsAPI(o.MetricsClient, o.Namespace, o.ResourceName, o.AllNamespaces, labelSelector, fieldSelector)
 	if err != nil {
 		return err
 	}
@@ -192,7 +202,7 @@ func (o TopPodOptions) RunTopPod() error {
 	if len(metrics.Items) == 0 {
 		// If the API server query is successful but all the pods are newly created,
 		// the metrics are probably not ready yet, so we return the error here in the first place.
-		err := verifyEmptyMetrics(o, selector)
+		err := verifyEmptyMetrics(o, labelSelector, fieldSelector)
 		if err != nil {
 			return err
 		}
@@ -208,7 +218,7 @@ func (o TopPodOptions) RunTopPod() error {
 	return o.Printer.PrintPodMetrics(metrics.Items, o.PrintContainers, o.AllNamespaces, o.NoHeaders, o.SortBy)
 }
 
-func getMetricsFromMetricsAPI(metricsClient metricsclientset.Interface, namespace, resourceName string, allNamespaces bool, selector labels.Selector) (*metricsapi.PodMetricsList, error) {
+func getMetricsFromMetricsAPI(metricsClient metricsclientset.Interface, namespace, resourceName string, allNamespaces bool, labelSelector labels.Selector, fieldSelector fields.Selector) (*metricsapi.PodMetricsList, error) {
 	var err error
 	ns := metav1.NamespaceAll
 	if !allNamespaces {
@@ -222,7 +232,7 @@ func getMetricsFromMetricsAPI(metricsClient metricsclientset.Interface, namespac
 		}
 		versionedMetrics.Items = []metricsv1beta1api.PodMetrics{*m}
 	} else {
-		versionedMetrics, err = metricsClient.MetricsV1beta1().PodMetricses(ns).List(context.TODO(), metav1.ListOptions{LabelSelector: selector.String()})
+		versionedMetrics, err = metricsClient.MetricsV1beta1().PodMetricses(ns).List(context.TODO(), metav1.ListOptions{LabelSelector: labelSelector.String(), FieldSelector: fieldSelector.String()})
 		if err != nil {
 			return nil, err
 		}
@@ -235,7 +245,7 @@ func getMetricsFromMetricsAPI(metricsClient metricsclientset.Interface, namespac
 	return metrics, nil
 }
 
-func verifyEmptyMetrics(o TopPodOptions, selector labels.Selector) error {
+func verifyEmptyMetrics(o TopPodOptions, labelSelector labels.Selector, fieldSelector fields.Selector) error {
 	if len(o.ResourceName) > 0 {
 		pod, err := o.PodClient.Pods(o.Namespace).Get(context.TODO(), o.ResourceName, metav1.GetOptions{})
 		if err != nil {
@@ -246,7 +256,8 @@ func verifyEmptyMetrics(o TopPodOptions, selector labels.Selector) error {
 		}
 	} else {
 		pods, err := o.PodClient.Pods(o.Namespace).List(context.TODO(), metav1.ListOptions{
-			LabelSelector: selector.String(),
+			LabelSelector: labelSelector.String(),
+			FieldSelector: fieldSelector.String(),
 		})
 		if err != nil {
 			return err

staging/src/k8s.io/kubectl/pkg/cmd/top/top_pod_test.go

@@ -107,10 +107,16 @@ func TestTopPod(t *testing.T) {
 		},
 		{
 			name:          "pod with label selector",
-			options:       &TopPodOptions{Selector: "key=value"},
+			options:       &TopPodOptions{LabelSelector: "key=value"},
 			expectedQuery: "labelSelector=" + url.QueryEscape("key=value"),
 			namespaces:    []string{testNS, testNS},
 		},
+		{
+			name:          "pod with field selector",
+			options:       &TopPodOptions{FieldSelector: "key=value"},
+			expectedQuery: "fieldSelector=" + url.QueryEscape("key=value"),
+			namespaces:    []string{testNS, testNS},
+		},
 		{
 			name:    "pod with container metrics",
 			options: &TopPodOptions{PrintContainers: true},