Delay pod deletion to handle deregistraton delay

config/rbac/role.yaml

@@ -45,6 +45,8 @@ rules:
   - get
   - list
   - watch
+  - patch
+  - delete
 - apiGroups:
   - ""
   resources:

config/webhook/manifests.v1beta1.yaml

@@ -48,6 +48,24 @@ metadata:
   creationTimestamp: null
   name: webhook
 webhooks:
+  - clientConfig:
+      caBundle: Cg==
+      service:
+        name: webhook-service
+        namespace: system
+        path: /validate-v1-pod
+    failurePolicy: Ignore
+    name: vpod.elbv2.k8s.aws
+    rules:
+      - apiGroups:
+        - ""
+        apiVersions:
+          - v1
+        operations:
+          - DELETE
+        resources:
+          - pods
+    sideEffects: NoneOnDryRun
   - clientConfig:
       caBundle: Cg==
       service:

main.go

@@ -33,6 +33,7 @@ import (
 	"sigs.k8s.io/aws-load-balancer-controller/pkg/aws"
 	"sigs.k8s.io/aws-load-balancer-controller/pkg/aws/throttle"
 	"sigs.k8s.io/aws-load-balancer-controller/pkg/config"
+	"sigs.k8s.io/aws-load-balancer-controller/pkg/gracefuldrain"
 	"sigs.k8s.io/aws-load-balancer-controller/pkg/inject"
 	"sigs.k8s.io/aws-load-balancer-controller/pkg/k8s"
 	"sigs.k8s.io/aws-load-balancer-controller/pkg/networking"
@@ -143,6 +144,14 @@ func main() {
 	elbv2webhook.NewTargetGroupBindingValidator(ctrl.Log).SetupWithManager(mgr)
 	//+kubebuilder:scaffold:builder
 
+	podGracefulDrain := gracefuldrain.NewPodGracefulDrain(controllerCFG.PodGracefulDrainConfig, mgr.GetClient(),
+		ctrl.Log.WithName("pod-graceful-drain"))
+	if err := mgr.Add(podGracefulDrain); err != nil {
+		setupLog.Error(err, "Unable to add pod-graceful-drain")
+		os.Exit(1)
+	}
+	corewebhook.NewPodValidator(podGracefulDrain, ctrl.Log).SetupWithManager(mgr)
+
 	stopChan := ctrl.SetupSignalHandler()
 	go func() {
 		setupLog.Info("starting podInfo repo")

pkg/config/controller_config.go

@@ -4,6 +4,7 @@ import (
 	"github.com/pkg/errors"
 	"github.com/spf13/pflag"
 	"sigs.k8s.io/aws-load-balancer-controller/pkg/aws"
+	"sigs.k8s.io/aws-load-balancer-controller/pkg/gracefuldrain"
 	"sigs.k8s.io/aws-load-balancer-controller/pkg/inject"
 )
 
@@ -33,6 +34,8 @@ type ControllerConfig struct {
 	IngressConfig IngressConfig
 	// Configurations for Addons feature
 	AddonsConfig AddonsConfig
+	// Configurations for Pod graaceful drain
+	PodGracefulDrainConfig gracefuldrain.Config
 
 	// Default AWS Tags that will be applied to all AWS resources managed by this controller.
 	DefaultTags map[string]string
@@ -61,12 +64,16 @@ func (cfg *ControllerConfig) BindFlags(fs *pflag.FlagSet) {
 	cfg.PodWebhookConfig.BindFlags(fs)
 	cfg.IngressConfig.BindFlags(fs)
 	cfg.AddonsConfig.BindFlags(fs)
+	cfg.PodGracefulDrainConfig.BindFlags(fs)
 }
 
 // Validate the controller configuration
 func (cfg *ControllerConfig) Validate() error {
 	if len(cfg.ClusterName) == 0 {
 		return errors.New("kubernetes cluster name must be specified")
 	}
+	if cfg.PodGracefulDrainConfig.PodGracefulDrainDelay < 0 {
+		return errors.New("pod-graceful-drain-delay cannot be negative")
+	}
 	return nil
 }

pkg/gracefuldrain/config.go

@@ -0,0 +1,19 @@
+package gracefuldrain
+
+import (
+	"github.com/spf13/pflag"
+	"time"
+)
+
+const (
+	flagPodGracefulDrainDelay = "pod-graceful-drain-delay"
+)
+
+type Config struct {
+	PodGracefulDrainDelay time.Duration
+}
+
+func (cfg *Config) BindFlags(fs *pflag.FlagSet) {
+	fs.DurationVar(&cfg.PodGracefulDrainDelay, flagPodGracefulDrainDelay, time.Duration(0),
+		`Deregistering pod's deletions are delayed while draining`)
+}