Update docs and log messages

internal/controller/stream_controller.go

@@ -44,6 +44,10 @@ type StreamReconciler struct {
 // - Initialize finalizer and ready condition if not present
 // - Delete stream if it is marked for deletion.
 // - Create or Update the stream
+//
+// A call to reconcile may perform only one action, expecting the reconciliation to be triggered again by an update.
+// For example: Setting the finalizer triggers a second reconciliation. Reconcile returns after setting the finalizer,
+// to prevent parallel reconciliations performing the same steps.
 func (r *StreamReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Result, error) {
 	log := klog.FromContext(ctx)
 
@@ -116,27 +120,28 @@ func (r *StreamReconciler) deleteStream(ctx context.Context, log logr.Logger, st
 		return fmt.Errorf("update ready condition: %w", err)
 	}
 
-	if stream.Spec.PreventDelete {
-		log.Info("PreventDelete set: skipping stream deletion.", "streamName", stream.Spec.Name)
-	} else if r.ReadOnly() {
-		log.Info("Read-only mode: skipping stream deletion.", "streamName", stream.Spec.Name)
-	} else {
+	if !stream.Spec.PreventDelete && !r.ReadOnly() {
 		log.Info("Deleting stream.")
-		err := r.WithJetStreamClient(mapToConnectionOptions(stream.Spec), func(js jetstream.JetStream) error {
+		err := r.WithJetStreamClient(getConnOpts(stream.Spec), func(js jetstream.JetStream) error {
 			return js.DeleteStream(ctx, stream.Spec.Name)
 		})
 		if errors.Is(err, jetstream.ErrStreamNotFound) {
 			log.Info("Managed stream was already deleted.")
 		} else if err != nil {
 			return fmt.Errorf("delete stream during finalization: %w", err)
 		}
+	} else {
+		log.Info("Skipping stream deletion.",
+			"streamName", stream.Spec.Name,
+			"preventDelete", stream.Spec.PreventDelete,
+			"read-only", r.ReadOnly(),
+		)
 	}
 
-	log.Info("Stream deleted. Removing stream finalizer.")
+	log.Info("Removing stream finalizer.")
 	if ok := controllerutil.RemoveFinalizer(stream, streamFinalizer); !ok {
 		return errors.New("failed to remove stream finalizer")
 	}
-
 	if err := r.Update(ctx, stream); err != nil {
 		return fmt.Errorf("remove finalizer: %w", err)
 	}
@@ -147,11 +152,12 @@ func (r *StreamReconciler) deleteStream(ctx context.Context, log logr.Logger, st
 func (r *StreamReconciler) createOrUpdate(ctx context.Context, log logr.Logger, stream *api.Stream) error {
 
 	// Create or Update the stream based on the spec
-	if stream.Spec.PreventUpdate {
-		log.Info("PreventUpdate is set: skipping stream creation/update.", "streamName", stream.Spec.Name)
-		return nil
-	} else if r.ReadOnly() {
-		log.Info("Read-only mode: skipping stream creation/update.", "streamName", stream.Spec.Name)
+	if stream.Spec.PreventDelete || r.ReadOnly() {
+		log.Info("Skipping stream creation or update.",
+			"streamName", stream.Spec.Name,
+			"preventDelete", stream.Spec.PreventDelete,
+			"read-only", r.ReadOnly(),
+		)
 		return nil
 	}
 
@@ -163,7 +169,7 @@ func (r *StreamReconciler) createOrUpdate(ctx context.Context, log logr.Logger,
 
 	// CreateOrUpdateStream is called on every reconciliation when the stream is not to be deleted.
 	// TODO(future-feature): Do we need to check if config differs?
-	err = r.WithJetStreamClient(mapToConnectionOptions(stream.Spec), func(js jetstream.JetStream) error {
+	err = r.WithJetStreamClient(getConnOpts(stream.Spec), func(js jetstream.JetStream) error {
 		log.Info("create or update stream", "streamName", targetConfig.Name)
 		_, err = js.CreateOrUpdateStream(ctx, targetConfig)
 		return err
@@ -193,7 +199,8 @@ func (r *StreamReconciler) createOrUpdate(ctx context.Context, log logr.Logger,
 	return nil
 }
 
-func mapToConnectionOptions(spec api.StreamSpec) *connectionOptions {
+// getConnOpts extracts nats connection relevant fields from the given stream spec as connectionOptions.
+func getConnOpts(spec api.StreamSpec) *connectionOptions {
 	return &connectionOptions{
 		Account: spec.Account, // TODO(review): Where does Spec.Account have to be considered?
 		Creds:   spec.Creds,