karmada/pkg/karmadactl/cordon.go

255 lines
7.3 KiB
Go

package karmadactl
import (
"context"
"encoding/json"
"errors"
"fmt"
"github.com/spf13/cobra"
corev1 "k8s.io/api/core/v1"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"k8s.io/apimachinery/pkg/types"
"k8s.io/apimachinery/pkg/util/strategicpatch"
"k8s.io/kubectl/pkg/util/templates"
clusterv1alpha1 "github.com/karmada-io/karmada/pkg/apis/cluster/v1alpha1"
karmadaclientset "github.com/karmada-io/karmada/pkg/generated/clientset/versioned"
"github.com/karmada-io/karmada/pkg/karmadactl/options"
)
var (
cordonShort = `Mark cluster as unschedulable`
cordonLong = `Mark cluster as unschedulable.`
uncordonShort = `Mark cluster as schedulable`
uncordonLong = `Mark cluster as schedulable.`
cordonExample = templates.Examples(`
# Mark cluster "foo" as unschedulable.
%[1]s cordon foo`)
uncordonExample = templates.Examples(`
# Mark cluster "foo" as schedulable.
%[1]s uncordon foo`)
)
const (
// DesiredCordon a flag indicate karmadactl.RunCordonOrUncordon cordon a cluster,
// cordon prevent new resource scheduler to cordoned cluster.
DesiredCordon = iota
// DesiredUnCordon a flag indicate karmadactl.RunCordonOrUncordon uncordon a cluster.
DesiredUnCordon
)
// NewCmdCordon defines the `cordon` command that mark cluster as unschedulable.
func NewCmdCordon(karmadaConfig KarmadaConfig, parentCommand string) *cobra.Command {
opts := CommandCordonOption{}
cmd := &cobra.Command{
Use: "cordon CLUSTER",
Short: cordonShort,
Long: cordonLong,
Example: fmt.Sprintf(cordonExample, parentCommand),
SilenceUsage: true,
DisableFlagsInUseLine: true,
RunE: func(cmd *cobra.Command, args []string) error {
if err := opts.Complete(args); err != nil {
return err
}
if err := RunCordonOrUncordon(DesiredCordon, karmadaConfig, opts); err != nil {
return err
}
return nil
},
}
flags := cmd.Flags()
opts.GlobalCommandOptions.AddFlags(flags)
flags.BoolVar(&opts.DryRun, "dry-run", false, "Run the command in dry-run mode, without making any server requests.")
return cmd
}
// NewCmdUncordon defines the `uncordon` command that mark cluster as schedulable.
func NewCmdUncordon(karmadaConfig KarmadaConfig, parentCommand string) *cobra.Command {
opts := CommandCordonOption{}
cmd := &cobra.Command{
Use: "uncordon CLUSTER",
Short: uncordonShort,
Long: uncordonLong,
Example: fmt.Sprintf(uncordonExample, parentCommand),
SilenceUsage: true,
DisableFlagsInUseLine: true,
RunE: func(cmd *cobra.Command, args []string) error {
if err := opts.Complete(args); err != nil {
return err
}
if err := RunCordonOrUncordon(DesiredUnCordon, karmadaConfig, opts); err != nil {
return err
}
return nil
},
}
flags := cmd.Flags()
opts.AddFlags(flags)
return cmd
}
// CommandCordonOption holds all command options for cordon and uncordon
type CommandCordonOption struct {
// global flags
options.GlobalCommandOptions
// ClusterName is the cluster's name that we are going to join with.
ClusterName string
// DryRun tells if run the command in dry-run mode, without making any server requests.
DryRun bool
}
// Complete ensures that options are valid and marshals them if necessary.
func (o *CommandCordonOption) Complete(args []string) error {
// Get cluster name from the command args.
if len(args) == 0 {
return errors.New("cluster name is required")
}
o.ClusterName = args[0]
return nil
}
// CordonHelper wraps functionality to cordon/uncordon cluster
type CordonHelper struct {
cluster *clusterv1alpha1.Cluster
desired int
}
// NewCordonHelper returns a new CordonHelper that help execute
// the cordon and uncordon commands
func NewCordonHelper(cluster *clusterv1alpha1.Cluster) *CordonHelper {
return &CordonHelper{
cluster: cluster,
}
}
// UpdateIfRequired returns true if unscheduler taint isn't already set,
// or false when no change is needed
func (c *CordonHelper) UpdateIfRequired(desired int) bool {
c.desired = desired
if desired == DesiredCordon && !c.hasUnschedulerTaint() {
return true
}
if desired == DesiredUnCordon && c.hasUnschedulerTaint() {
return true
}
return false
}
func (c *CordonHelper) hasUnschedulerTaint() bool {
unschedulerTaint := corev1.Taint{
Key: clusterv1alpha1.TaintClusterUnscheduler,
Effect: corev1.TaintEffectNoSchedule,
}
for _, taint := range c.cluster.Spec.Taints {
if taint.MatchTaint(&unschedulerTaint) {
return true
}
}
return false
}
// PatchOrReplace uses given karmada clientset to update the cluster unschedulable scheduler, either by patching or
// updating the given cluster object; it may return error if the object cannot be encoded as
// JSON, or if either patch or update calls fail; it will also return error whenever creating a patch has failed
func (c *CordonHelper) PatchOrReplace(controlPlaneClient *karmadaclientset.Clientset) error {
client := controlPlaneClient.ClusterV1alpha1().Clusters()
oldData, err := json.Marshal(c.cluster)
if err != nil {
return err
}
unschedulerTaint := corev1.Taint{
Key: clusterv1alpha1.TaintClusterUnscheduler,
Effect: corev1.TaintEffectNoSchedule,
}
if c.desired == DesiredCordon {
c.cluster.Spec.Taints = append(c.cluster.Spec.Taints, unschedulerTaint)
}
if c.desired == DesiredUnCordon {
for i, n := 0, len(c.cluster.Spec.Taints); i < n; i++ {
if c.cluster.Spec.Taints[i].MatchTaint(&unschedulerTaint) {
c.cluster.Spec.Taints[i] = c.cluster.Spec.Taints[n-1]
c.cluster.Spec.Taints = c.cluster.Spec.Taints[:n-1]
break
}
}
}
newData, err := json.Marshal(c.cluster)
if err != nil {
return err
}
patchBytes, err := strategicpatch.CreateTwoWayMergePatch(oldData, newData, c.cluster)
if err == nil {
_, err = client.Patch(context.TODO(), c.cluster.Name, types.MergePatchType, patchBytes, metav1.PatchOptions{})
} else {
_, err = client.Update(context.TODO(), c.cluster, metav1.UpdateOptions{})
}
return err
}
// RunCordonOrUncordon exec marks the cluster unschedulable or schedulable according to desired.
// if true cordon cluster otherwise uncordon cluster.
func RunCordonOrUncordon(desired int, karmadaConfig KarmadaConfig, opts CommandCordonOption) error {
cordonOrUncordon := "cordon"
if desired == DesiredUnCordon {
cordonOrUncordon = "un" + cordonOrUncordon
}
// Get control plane kube-apiserver client
controlPlaneRestConfig, err := karmadaConfig.GetRestConfig(opts.KarmadaContext, opts.KubeConfig)
if err != nil {
return fmt.Errorf("failed to get control plane rest config. context: %s, kube-config: %s, error: %v",
opts.KarmadaContext, opts.KubeConfig, err)
}
controlPlaneKarmadaClient := karmadaclientset.NewForConfigOrDie(controlPlaneRestConfig)
cluster, err := controlPlaneKarmadaClient.ClusterV1alpha1().Clusters().Get(context.TODO(), opts.ClusterName, metav1.GetOptions{})
if err != nil {
return err
}
cordonHelper := NewCordonHelper(cluster)
if !cordonHelper.UpdateIfRequired(desired) {
fmt.Printf("%s cluster %s\n", cluster.Name, alreadyStr(desired))
return nil
}
if !opts.DryRun {
err := cordonHelper.PatchOrReplace(controlPlaneKarmadaClient)
if err != nil {
return err
}
}
fmt.Printf("%s cluster %sed\n", cluster.Name, cordonOrUncordon)
return nil
}
func alreadyStr(desired int) string {
if desired == DesiredCordon {
return "already cordoned"
}
return "already uncordoned"
}