controller.go

package storage

import (
	"context"
	"errors"
	"fmt"

	"github.com/go-logr/logr"
	monitoringv1 "github.com/prometheus-operator/prometheus-operator/pkg/apis/monitoring/v1"
	appsv1 "k8s.io/api/apps/v1"
	corev1 "k8s.io/api/core/v1"
	apierrors "k8s.io/apimachinery/pkg/api/errors"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/apimachinery/pkg/types"
	"k8s.io/client-go/rest"
	"k8s.io/client-go/tools/record"
	ctrl "sigs.k8s.io/controller-runtime"
	"sigs.k8s.io/controller-runtime/pkg/builder"
	"sigs.k8s.io/controller-runtime/pkg/client"
	"sigs.k8s.io/controller-runtime/pkg/controller/controllerutil"
	"sigs.k8s.io/controller-runtime/pkg/handler"
	"sigs.k8s.io/controller-runtime/pkg/log"
	"sigs.k8s.io/controller-runtime/pkg/predicate"
	"sigs.k8s.io/controller-runtime/pkg/reconcile"
	"sigs.k8s.io/controller-runtime/pkg/source"

	"github.com/ydb-platform/ydb-kubernetes-operator/api/v1alpha1"
	ydbannotations "github.com/ydb-platform/ydb-kubernetes-operator/internal/annotations"
	. "github.com/ydb-platform/ydb-kubernetes-operator/internal/controllers/constants" //nolint:revive,stylecheck
	"github.com/ydb-platform/ydb-kubernetes-operator/internal/resources"
)

// Reconciler reconciles a Storage object
type Reconciler struct {
	client.Client
	Scheme   *runtime.Scheme
	Config   *rest.Config
	Recorder record.EventRecorder
	Log      logr.Logger

	WithServiceMonitors bool
}

//+kubebuilder:rbac:groups=ydb.tech,resources=storages,verbs=get;list;watch;create;update;patch;delete
//+kubebuilder:rbac:groups=ydb.tech,resources=storages/status,verbs=get;update;patch
//+kubebuilder:rbac:groups=ydb.tech,resources=storages/finalizers,verbs=update
//+kubebuilder:rbac:groups=ydb.tech,resources=remotestoragenodesets,verbs=get;list;watch;create;update;patch;delete
//+kubebuilder:rbac:groups=ydb.tech,resources=remotestoragenodesets/status,verbs=get;update;patch
//+kubebuilder:rbac:groups=ydb.tech,resources=remotestoragenodesets/finalizers,verbs=update
//+kubebuilder:rbac:groups=ydb.tech,resources=storagenodesets,verbs=get;list;watch;create;update;patch;delete
//+kubebuilder:rbac:groups=ydb.tech,resources=storagenodesets/status,verbs=get;update;patch
//+kubebuilder:rbac:groups=ydb.tech,resources=storagenodesets/finalizers,verbs=update
//+kubebuilder:rbac:groups=core,resources=services,verbs=get;list;watch;create;update;patch;delete
//+kubebuilder:rbac:groups=core,resources=services/status,verbs=get;update;patch
//+kubebuilder:rbac:groups=core,resources=services/finalizers,verbs=get;list;watch
//+kubebuilder:rbac:groups=core,resources=configmaps,verbs=get;list;watch;create;update;patch;delete
//+kubebuilder:rbac:groups=core,resources=configmaps/status,verbs=get;update;patch
//+kubebuilder:rbac:groups=core,resources=secrets,verbs=get;list;watch;create;update;patch;delete
//+kubebuilder:rbac:groups=core,resources=secrets/status,verbs=get;update;patch
//+kubebuilder:rbac:groups=apps,resources=statefulsets,verbs=get;list;watch;create;update;patch;delete
//+kubebuilder:rbac:groups=apps,resources=statefulsets/status,verbs=get;update;patch
//+kubebuilder:rbac:groups=apps,resources=statefulsets/finalizers,verbs=get;list;watch
//+kubebuilder:rbac:groups=batch,resources=jobs,verbs=get;list;watch;create;update;patch;delete
//+kubebuilder:rbac:groups=batch,resources=jobs/status,verbs=get;update;patch
//+kubebuilder:rbac:groups=monitoring.coreos.com,resources=servicemonitors,verbs=get;list;watch;create;update;patch;delete
//+kubebuilder:rbac:groups=monitoring.coreos.com,resources=servicemonitors/status,verbs=get;update;patch

// Reconcile is part of the main kubernetes reconciliation loop which aims to
// move the current state of the cluster closer to the desired state.
func (r *Reconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Result, error) {
	r.Log = log.FromContext(ctx)

	resource := &v1alpha1.Storage{}
	err := r.Get(ctx, req.NamespacedName, resource)
	if err != nil {
		if apierrors.IsNotFound(err) {
			r.Log.Info("Storage resource not found")
			return ctrl.Result{Requeue: false}, nil
		}
		r.Log.Error(err, "unexpected Get error")
		return ctrl.Result{RequeueAfter: DefaultRequeueDelay}, err
	}

	//nolint:nestif
	// examine DeletionTimestamp to determine if object is under deletion
	if resource.ObjectMeta.DeletionTimestamp.IsZero() {
		// The object is not being deleted, so if it does not have our finalizer,
		// then lets add the finalizer and update the object. This is equivalent
		// to registering our finalizer.
		if !controllerutil.ContainsFinalizer(resource, ydbannotations.StorageFinalizerKey) {
			controllerutil.AddFinalizer(resource, ydbannotations.StorageFinalizerKey)
			if err := r.Client.Update(ctx, resource); err != nil {
				return ctrl.Result{RequeueAfter: DefaultRequeueDelay}, err
			}
		}
	} else {
		// The object is being deleted
		if controllerutil.ContainsFinalizer(resource, ydbannotations.StorageFinalizerKey) {
			// our finalizer is present, so lets handle any external dependency
			if err := r.checkExistingDatabases(ctx, resource); err != nil {
				// if fail to check dependency existence, return with error
				// so that it can be retried.
				return ctrl.Result{RequeueAfter: DefaultRequeueDelay}, err
			}

			// remove our finalizer from the list and update it.
			controllerutil.RemoveFinalizer(resource, ydbannotations.StorageFinalizerKey)
			if err := r.Client.Update(ctx, resource); err != nil {
				return ctrl.Result{RequeueAfter: DefaultRequeueDelay}, err
			}
		}

		// Stop reconciliation as the item is being deleted
		return ctrl.Result{Requeue: false}, nil
	}

	result, err := r.Sync(ctx, resource)
	if err != nil {
		r.Log.Error(err, "unexpected Sync error")
	}

	return result, err
}

func createFieldIndexers(mgr ctrl.Manager) error {
	if err := mgr.GetFieldIndexer().IndexField(
		context.Background(),
		&v1alpha1.RemoteStorageNodeSet{},
		OwnerControllerField,
		func(obj client.Object) []string {
			// grab the RemoteStorageNodeSet object, extract the owner...
			remoteStorageNodeSet := obj.(*v1alpha1.RemoteStorageNodeSet)
			owner := metav1.GetControllerOf(remoteStorageNodeSet)
			if owner == nil {
				return nil
			}
			// ...make sure it's a Storage...
			if owner.APIVersion != v1alpha1.GroupVersion.String() || owner.Kind != StorageKind {
				return nil
			}

			// ...and if so, return it
			return []string{owner.Name}
		}); err != nil {
		return err
	}

	if err := mgr.GetFieldIndexer().IndexField(
		context.Background(),
		&v1alpha1.StorageNodeSet{},
		OwnerControllerField,
		func(obj client.Object) []string {
			// grab the StorageNodeSet object, extract the owner...
			storageNodeSet := obj.(*v1alpha1.StorageNodeSet)
			owner := metav1.GetControllerOf(storageNodeSet)
			if owner == nil {
				return nil
			}
			// ...make sure it's a Storage...
			if owner.APIVersion != v1alpha1.GroupVersion.String() || owner.Kind != StorageKind {
				return nil
			}

			// ...and if so, return it
			return []string{owner.Name}
		}); err != nil {
		return err
	}

	if err := mgr.GetFieldIndexer().IndexField(
		context.Background(),
		&v1alpha1.Database{},
		StorageRefField,
		func(obj client.Object) []string {
			// grab the Database object, extract the .spec.storageRef.name...
			database := obj.(*v1alpha1.Database)
			return []string{database.Spec.StorageClusterRef.Name}
		}); err != nil {
		return err
	}

	return mgr.GetFieldIndexer().IndexField(
		context.Background(),
		&v1alpha1.Storage{},
		SecretField,
		func(obj client.Object) []string {
			secrets := []string{}
			storage := obj.(*v1alpha1.Storage)
			for _, secret := range storage.Spec.Secrets {
				secrets = append(secrets, secret.Name)
			}

			return secrets
		})
}

// SetupWithManager sets up the controller with the Manager.
func (r *Reconciler) SetupWithManager(mgr ctrl.Manager) error {
	r.Recorder = mgr.GetEventRecorderFor(StorageKind)
	controller := ctrl.NewControllerManagedBy(mgr)

	if err := createFieldIndexers(mgr); err != nil {
		r.Log.Error(err, "unexpected FieldIndexer error")
		return err
	}

	if r.WithServiceMonitors {
		controller = controller.
			Owns(&monitoringv1.ServiceMonitor{})
	}

	return controller.
		For(&v1alpha1.Storage{},
			builder.WithPredicates(predicate.GenerationChangedPredicate{}),
		).
		Owns(&v1alpha1.RemoteStorageNodeSet{},
			builder.WithPredicates(resources.LastAppliedAnnotationPredicate()), // TODO: YDBOPS-9194
		).
		Owns(&v1alpha1.StorageNodeSet{},
			builder.WithPredicates(resources.LastAppliedAnnotationPredicate()), // TODO: YDBOPS-9194
		).
		Owns(&appsv1.StatefulSet{},
			builder.WithPredicates(predicate.GenerationChangedPredicate{}),
		).
		Owns(&corev1.ConfigMap{},
			builder.WithPredicates(predicate.ResourceVersionChangedPredicate{}),
		).
		Owns(&corev1.Service{},
			builder.WithPredicates(predicate.ResourceVersionChangedPredicate{}),
		).
		Watches(
			&source.Kind{Type: &corev1.Secret{}},
			handler.EnqueueRequestsFromMapFunc(r.findStoragesForSecret),
			builder.WithPredicates(predicate.ResourceVersionChangedPredicate{}),
		).
		WithEventFilter(resources.IsStorageCreatePredicate()).
		WithEventFilter(resources.IgnoreDeleteStateUnknownPredicate()).
		Complete(r)
}

func (r *Reconciler) findStoragesForSecret(secret client.Object) []reconcile.Request {
	attachedStorages := &v1alpha1.StorageList{}
	err := r.List(
		context.Background(),
		attachedStorages,
		client.InNamespace(secret.GetNamespace()),
		client.MatchingFields{SecretField: secret.GetName()},
	)
	if err != nil {
		return []reconcile.Request{}
	}

	requests := make([]reconcile.Request, len(attachedStorages.Items))
	for i, item := range attachedStorages.Items {
		requests[i] = reconcile.Request{
			NamespacedName: types.NamespacedName{
				Name:      item.GetName(),
				Namespace: item.GetNamespace(),
			},
		}
	}
	return requests
}

func (r *Reconciler) checkExistingDatabases(
	ctx context.Context,
	storage *v1alpha1.Storage,
) error {
	databaseList := &v1alpha1.DatabaseList{}
	err := r.Client.List(
		ctx,
		databaseList,
		client.InNamespace(storage.Namespace),
		client.MatchingFields{
			StorageRefField: storage.Name,
		},
	)
	if err != nil {
		r.Log.Error(err, "failed to list Databases")
		r.Recorder.Event(
			storage,
			corev1.EventTypeWarning,
			"ControllerError",
			fmt.Sprintf("Failed to list Databases: %s", err),
		)
		return err
	}

	if len(databaseList.Items) > 0 {
		var databases []string
		for _, database := range databaseList.Items {
			databases = append(databases, database.Name)
		}
		errMessage := fmt.Sprintf("Waiting for existing Databases to be deleted: %v", databases)
		r.Log.Info(errMessage)
		r.Recorder.Event(
			storage,
			corev1.EventTypeNormal,
			string(StorageProvisioning),
			fmt.Sprintf(errMessage, databases),
		)
		return errors.New(errMessage)
	}

	return nil
}