constellation/operators/constellation-node-operator/controllers/autoscalingstrategy_controller.go
Malte Poll 69d47730c8 [node operator] AutoscalingStrategy controller impl
Signed-off-by: Malte Poll <mp@edgeless.systems>
2022-08-09 10:29:04 +02:00

97 lines
3.8 KiB
Go

package controllers
import (
"context"
appsv1 "k8s.io/api/apps/v1"
"k8s.io/apimachinery/pkg/runtime"
"k8s.io/apimachinery/pkg/types"
"k8s.io/client-go/util/retry"
ctrl "sigs.k8s.io/controller-runtime"
"sigs.k8s.io/controller-runtime/pkg/client"
"sigs.k8s.io/controller-runtime/pkg/log"
updatev1alpha1 "github.com/edgelesssys/constellation/operators/constellation-node-operator/api/v1alpha1"
)
// AutoscalingStrategyReconciler reconciles a AutoscalingStrategy object
type AutoscalingStrategyReconciler struct {
client.Client
Scheme *runtime.Scheme
}
//+kubebuilder:rbac:groups=update.edgeless.systems,resources=autoscalingstrategies,verbs=get;list;watch;create;update;patch;delete
//+kubebuilder:rbac:groups=update.edgeless.systems,resources=autoscalingstrategies/status,verbs=get;update;patch
//+kubebuilder:rbac:groups=update.edgeless.systems,resources=autoscalingstrategies/finalizers,verbs=update
//+kubebuilder:rbac:groups=apps,resources=deployments,verbs=get;list;watch;create;update;delete
// Reconcile enabled or disables the cluster-autoscaler based on the AutoscalingStrategy spec
// by modifying the replicas of the Deployment.
func (r *AutoscalingStrategyReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Result, error) {
logr := log.FromContext(ctx)
var desiredAutoscalingStrategy updatev1alpha1.AutoscalingStrategy
if err := r.Get(ctx, req.NamespacedName, &desiredAutoscalingStrategy); err != nil {
logr.Error(err, "Unable to fetch AutoscalingStrategy")
return ctrl.Result{}, client.IgnoreNotFound(err)
}
var expectedReplicas int32
if desiredAutoscalingStrategy.Spec.Enabled {
expectedReplicas = 1
}
var autoscalerDeployment appsv1.Deployment
if err := r.Get(ctx, client.ObjectKey{Namespace: desiredAutoscalingStrategy.Spec.DeploymentNamespace, Name: desiredAutoscalingStrategy.Spec.DeploymentName}, &autoscalerDeployment); err != nil {
logr.Error(err, "Unable to fetch autoscaler Deployment")
return ctrl.Result{}, client.IgnoreNotFound(err)
}
if autoscalerDeployment.Spec.Replicas == nil || *autoscalerDeployment.Spec.Replicas == 0 {
desiredAutoscalingStrategy.Status.Enabled = false
desiredAutoscalingStrategy.Status.Replicas = 0
} else {
desiredAutoscalingStrategy.Status.Enabled = true
desiredAutoscalingStrategy.Status.Replicas = *autoscalerDeployment.Spec.Replicas
}
if err := r.tryUpdateStatus(ctx, req.NamespacedName, desiredAutoscalingStrategy.Status); err != nil {
logr.Error(err, "Unable to update AutoscalingStrategy status")
return ctrl.Result{}, err
}
if autoscalerDeployment.Spec.Replicas == nil || *autoscalerDeployment.Spec.Replicas != expectedReplicas {
logr.Info("Updating autoscaling replicas", "expectedReplicas", expectedReplicas)
autoscalerDeployment.Spec.Replicas = &expectedReplicas
if err := r.Update(ctx, &autoscalerDeployment); err != nil {
logr.Error(err, "Unable to update autoscaler Deployment")
return ctrl.Result{}, err
}
return ctrl.Result{Requeue: true}, nil
}
return ctrl.Result{}, nil
}
// SetupWithManager sets up the controller with the Manager.
func (r *AutoscalingStrategyReconciler) SetupWithManager(mgr ctrl.Manager) error {
return ctrl.NewControllerManagedBy(mgr).
For(&updatev1alpha1.AutoscalingStrategy{}).
Complete(r)
}
// tryUpdateStatus attempts to update the AutoscalingStrategy status field in a retry loop.
func (r *AutoscalingStrategyReconciler) tryUpdateStatus(ctx context.Context, name types.NamespacedName, status updatev1alpha1.AutoscalingStrategyStatus) error {
return retry.RetryOnConflict(retry.DefaultRetry, func() error {
var autoscalingStrategy updatev1alpha1.AutoscalingStrategy
if err := r.Get(ctx, name, &autoscalingStrategy); err != nil {
return err
}
autoscalingStrategy.Status = *status.DeepCopy()
if err := r.Status().Update(ctx, &autoscalingStrategy); err != nil {
return err
}
return nil
})
}