feat(controller-runtime): Add consumer controller (#212)

* implement consumerSpecToConfig

* implement consumer resource initialization

* implement consumer update/creation

* implement preventUpdate, readonly and namespace restrictions

Checks for the PreventUpdate or readonly mode during creation/update.
Skips reconciliation when resource is in namespace not matching restriction.

* test consumer creation on alternative server

* implement consumer deletion

* handle deletion when the underlying stream was deleted

* add missing GenerationChanged event filter to consumerReconciler

* update logging

Set streamName and consumerName fields once.
Reword log messages.

Author: adriandieter

internal/controller/consumer_controller.go

@@ -18,9 +18,18 @@ package controller
 
 import (
 	"context"
+	"errors"
+	"fmt"
+	"github.com/go-logr/logr"
+	"github.com/nats-io/nats.go/jetstream"
+	v1 "k8s.io/api/core/v1"
+	apierrors "k8s.io/apimachinery/pkg/api/errors"
 	"k8s.io/klog/v2"
+	"sigs.k8s.io/controller-runtime/pkg/controller/controllerutil"
+	"sigs.k8s.io/controller-runtime/pkg/predicate"
+	"time"
 
-	jetstreamnatsiov1beta2 "github.com/nats-io/nack/pkg/jetstream/apis/jetstream/v1beta2"
+	api "github.com/nats-io/nack/pkg/jetstream/apis/jetstream/v1beta2"
 	ctrl "sigs.k8s.io/controller-runtime"
 )
 
@@ -36,14 +45,264 @@ type ConsumerReconciler struct {
 // - https://pkg.go.dev/sigs.k8s.io/[email protected]/pkg/reconcile
 func (r *ConsumerReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Result, error) {
 	log := klog.FromContext(ctx)
-	log.Info("reconcile", "namespace", req.Namespace, "name", req.Name)
 
+	if ok := r.ValidNamespace(req.Namespace); !ok {
+		log.Info("Controller restricted to namespace, skipping reconciliation.")
+		return ctrl.Result{}, nil
+	}
+
+	// Fetch consumer resource
+	consumer := &api.Consumer{}
+	if err := r.Get(ctx, req.NamespacedName, consumer); err != nil {
+		if apierrors.IsNotFound(err) {
+			log.Info("Consumer resource not found. Ignoring since object must be deleted.")
+			return ctrl.Result{}, nil
+		}
+		return ctrl.Result{}, fmt.Errorf("get consumer resource '%s': %w", req.NamespacedName.String(), err)
+	}
+
+	log = log.WithValues(
+		"streamName", consumer.Spec.StreamName,
+		"consumerName", consumer.Spec.DurableName,
+	)
+
+	// Update ready status to unknown when no status is set
+	if consumer.Status.Conditions == nil || len(consumer.Status.Conditions) == 0 {
+		log.Info("Setting initial ready condition to unknown.")
+		consumer.Status.Conditions = updateReadyCondition(consumer.Status.Conditions, v1.ConditionUnknown, "Reconciling", "Starting reconciliation")
+		err := r.Status().Update(ctx, consumer)
+		if err != nil {
+			return ctrl.Result{}, fmt.Errorf("set condition unknown: %w", err)
+		}
+		return ctrl.Result{Requeue: true}, nil
+	}
+
+	// Add finalizer
+	if !controllerutil.ContainsFinalizer(consumer, consumerFinalizer) {
+		log.Info("Adding consumer finalizer.")
+		if ok := controllerutil.AddFinalizer(consumer, consumerFinalizer); !ok {
+			return ctrl.Result{}, errors.New("failed to add finalizer to consumer resource")
+		}
+
+		if err := r.Update(ctx, consumer); err != nil {
+			return ctrl.Result{}, fmt.Errorf("update consumer resource to add finalizer: %w", err)
+		}
+		return ctrl.Result{}, nil
+	}
+
+	// Check Deletion
+	markedForDeletion := consumer.GetDeletionTimestamp() != nil
+	if markedForDeletion {
+		if controllerutil.ContainsFinalizer(consumer, consumerFinalizer) {
+			err := r.deleteConsumer(ctx, log, consumer)
+			if err != nil {
+				return ctrl.Result{}, fmt.Errorf("delete consumer: %w", err)
+			}
+		} else {
+			log.Info("Consumer marked for deletion and already finalized. Ignoring.")
+		}
+
+		return ctrl.Result{}, nil
+	}
+
+	// Create or update stream
+	if err := r.createOrUpdate(ctx, log, consumer); err != nil {
+		return ctrl.Result{}, fmt.Errorf("create or update: %s", err)
+	}
 	return ctrl.Result{}, nil
 }
 
+func (r *ConsumerReconciler) deleteConsumer(ctx context.Context, log logr.Logger, consumer *api.Consumer) error {
+
+	// Set status to not false
+	consumer.Status.Conditions = updateReadyCondition(consumer.Status.Conditions, v1.ConditionFalse, "Finalizing", "Performing finalizer operations.")
+	if err := r.Status().Update(ctx, consumer); err != nil {
+		return fmt.Errorf("update ready condition: %w", err)
+	}
+
+	if !consumer.Spec.PreventDelete && !r.ReadOnly() {
+		err := r.WithJetStreamClient(consumerConnOpts(consumer.Spec), func(js jetstream.JetStream) error {
+			return js.DeleteConsumer(ctx, consumer.Spec.StreamName, consumer.Spec.DurableName)
+		})
+		switch {
+		case errors.Is(err, jetstream.ErrConsumerNotFound):
+			log.Info("Consumer does not exist. Unable to delete.")
+		case errors.Is(err, jetstream.ErrStreamNotFound):
+			log.Info("Stream of consumer does not exist. Unable to delete.")
+		case err != nil:
+			return fmt.Errorf("delete jetstream consumer: %w", err)
+		default:
+			log.Info("Consumer deleted.")
+		}
+	} else {
+		log.Info("Skipping consumer deletion.",
+			"consumerName", consumer.Spec.DurableName,
+			"preventDelete", consumer.Spec.PreventDelete,
+			"read-only", r.ReadOnly(),
+		)
+	}
+
+	log.Info("Removing consumer finalizer.")
+	if ok := controllerutil.RemoveFinalizer(consumer, consumerFinalizer); !ok {
+		return errors.New("failed to remove consumer finalizer")
+	}
+	if err := r.Update(ctx, consumer); err != nil {
+		return fmt.Errorf("remove finalizer: %w", err)
+	}
+
+	return nil
+}
+
+func (r *ConsumerReconciler) createOrUpdate(ctx context.Context, log klog.Logger, consumer *api.Consumer) error {
+
+	// Create or Update the stream based on the spec
+	if consumer.Spec.PreventUpdate || r.ReadOnly() {
+		log.Info("Skipping consumer creation or update.",
+			"preventDelete", consumer.Spec.PreventDelete,
+			"read-only", r.ReadOnly(),
+		)
+		return nil
+	}
+
+	// Map spec to consumer target config
+	targetConfig, err := consumerSpecToConfig(&consumer.Spec)
+	if err != nil {
+		return fmt.Errorf("map consumer spec to target config: %w", err)
+	}
+
+	err = r.WithJetStreamClient(consumerConnOpts(consumer.Spec), func(js jetstream.JetStream) error {
+		log.Info("Consumer created or updated.")
+		_, err := js.CreateOrUpdateConsumer(ctx, consumer.Spec.StreamName, *targetConfig)
+		return err
+	})
+	if err != nil {
+		err = fmt.Errorf("create or update consumer: %w", err)
+		consumer.Status.Conditions = updateReadyCondition(consumer.Status.Conditions, v1.ConditionFalse, "Errored", err.Error())
+		if err := r.Status().Update(ctx, consumer); err != nil {
+			log.Error(err, "Failed to update ready condition to Errored.")
+		}
+		return err
+	}
+
+	// update the observed generation and ready status
+	consumer.Status.ObservedGeneration = consumer.Generation
+	consumer.Status.Conditions = updateReadyCondition(
+		consumer.Status.Conditions,
+		v1.ConditionTrue,
+		"Reconciling",
+		"Consumer successfully created or updated.",
+	)
+	err = r.Status().Update(ctx, consumer)
+	if err != nil {
+		return fmt.Errorf("update ready condition: %w", err)
+	}
+
+	return nil
+}
+
+func consumerConnOpts(spec api.ConsumerSpec) *connectionOptions {
+	return &connectionOptions{
+		Account: spec.Account,
+		Creds:   spec.Creds,
+		Nkey:    spec.Nkey,
+		Servers: spec.Servers,
+		TLS:     spec.TLS,
+	}
+}
+
+func consumerSpecToConfig(spec *api.ConsumerSpec) (*jetstream.ConsumerConfig, error) {
+
+	config := &jetstream.ConsumerConfig{
+		Durable:            spec.DurableName,
+		Description:        spec.Description,
+		OptStartSeq:        uint64(spec.OptStartSeq),
+		MaxDeliver:         spec.MaxDeliver,
+		FilterSubject:      spec.FilterSubject,
+		RateLimit:          uint64(spec.RateLimitBps),
+		SampleFrequency:    spec.SampleFreq,
+		MaxWaiting:         spec.MaxWaiting,
+		MaxAckPending:      spec.MaxAckPending,
+		HeadersOnly:        spec.HeadersOnly,
+		MaxRequestBatch:    spec.MaxRequestBatch,
+		MaxRequestMaxBytes: spec.MaxRequestMaxBytes,
+		Replicas:           spec.Replicas,
+		MemoryStorage:      spec.MemStorage,
+		FilterSubjects:     spec.FilterSubjects,
+		Metadata:           spec.Metadata,
+
+		// Explicitly set not (yet) mapped fields
+		Name:              "",
+		InactiveThreshold: 0,
+	}
+
+	// DeliverPolicy
+	if spec.DeliverPolicy != "" {
+		err := config.DeliverPolicy.UnmarshalJSON(asJsonString(spec.DeliverPolicy))
+		if err != nil {
+			return nil, fmt.Errorf("invalid delivery policy: %w", err)
+		}
+	}
+
+	//	OptStartTime RFC3339
+	if spec.OptStartTime != "" {
+		t, err := time.Parse(time.RFC3339, spec.OptStartTime)
+		if err != nil {
+			return nil, fmt.Errorf("invalid opt start time: %w", err)
+		}
+		config.OptStartTime = &t
+	}
+
+	//	AckPolicy
+	if spec.AckPolicy != "" {
+		err := config.AckPolicy.UnmarshalJSON(asJsonString(spec.AckPolicy))
+		if err != nil {
+			return nil, fmt.Errorf("invalid ack policy: %w", err)
+		}
+	}
+
+	//	AckWait
+	if spec.AckWait != "" {
+		d, err := time.ParseDuration(spec.AckWait)
+		if err != nil {
+			return nil, fmt.Errorf("invalid ack wait duration: %w", err)
+		}
+		config.AckWait = d
+	}
+
+	//BackOff
+	for _, bo := range spec.BackOff {
+		d, err := time.ParseDuration(bo)
+		if err != nil {
+			return nil, fmt.Errorf("invalid backoff: %w", err)
+		}
+
+		config.BackOff = append(config.BackOff, d)
+	}
+
+	//	ReplayPolicy
+	if spec.ReplayPolicy != "" {
+		err := config.ReplayPolicy.UnmarshalJSON(asJsonString(spec.ReplayPolicy))
+		if err != nil {
+			return nil, fmt.Errorf("invalid replay policy: %w", err)
+		}
+	}
+
+	//	MaxRequestExpires
+	if spec.MaxRequestExpires != "" {
+		d, err := time.ParseDuration(spec.MaxRequestExpires)
+		if err != nil {
+			return nil, fmt.Errorf("invalid opt start time: %w", err)
+		}
+		config.MaxRequestExpires = d
+	}
+
+	return config, nil
+}
+
 // SetupWithManager sets up the controller with the Manager.
 func (r *ConsumerReconciler) SetupWithManager(mgr ctrl.Manager) error {
 	return ctrl.NewControllerManagedBy(mgr).
-		For(&jetstreamnatsiov1beta2.Consumer{}).
+		For(&api.Consumer{}).
+		WithEventFilter(predicate.GenerationChangedPredicate{}).
 		Complete(r)
 }