Stop logging noisy errors when finishing/canceling scenario

webhosting-operator/pkg/experiment/generator/reconciler.go

@@ -60,7 +60,7 @@ func (r *Every) AddToManager(mgr manager.Manager) error {
 			RateLimiter:             &workqueue.BucketRateLimiter{Limiter: rate.NewLimiter(r.Rate, int(r.Rate))},
 		}).
 		WatchesRawSource(EmitN(reconcileWorkers), &handler.EnqueueRequestForObject{}).
-		Complete(r)
+		Complete(StopOnContextCanceled(r))
 }
 
 func (r *Every) Reconcile(ctx context.Context, _ reconcile.Request) (reconcile.Result, error) {
@@ -122,7 +122,7 @@ func (r *ForEach[T]) AddToManager(mgr manager.Manager) error {
 				GenericFunc: func(event.GenericEvent) bool { return false },
 			}),
 		).
-		Complete(r)
+		Complete(StopOnContextCanceled(r))
 }
 
 func (r *ForEach[T]) Reconcile(ctx context.Context, request reconcile.Request) (reconcile.Result, error) {

webhosting-operator/pkg/experiment/generator/utils.go

@@ -18,6 +18,7 @@ package generator
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"sync"
 	"time"
@@ -32,6 +33,7 @@ import (
 	"sigs.k8s.io/controller-runtime/pkg/handler"
 	logf "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"
 )
 
@@ -62,6 +64,19 @@ func EmitN(n int) source.Source {
 	})
 }
 
+// StopOnContextCanceled wraps the given reconciler so that "context canceled" errors are ignored. This is helpful when
+// a reconciler is expected to be canceled (e.g., when the scenario finishes). We neither need to retry nor log on such
+// errors. We can just stop silently.
+func StopOnContextCanceled(r reconcile.Reconciler) reconcile.Reconciler {
+	return reconcile.Func(func(ctx context.Context, request reconcile.Request) (reconcile.Result, error) {
+		result, err := r.Reconcile(ctx, request)
+		if errors.Is(err, context.Canceled) {
+			err = nil
+		}
+		return result, err
+	})
+}
+
 // NTimesConcurrently runs the given action n times. It distributes the work across the given number of concurrent
 // workers.
 func NTimesConcurrently(n, workers int, do func() error) error {