Separate in-cluster build and image existence verification (#33)

This PR removes the image existance verification from
Sync API of the build package and moves it into the
handleBuild function of the module reconcilier(prior
to calling the Sync API)

Author: yevgeny-shnaidman

controllers/module_reconciler.go

@@ -21,11 +21,13 @@ import (
 	"fmt"
 
 	kmmv1beta1 "github.com/kubernetes-sigs/kernel-module-management/api/v1beta1"
+	"github.com/kubernetes-sigs/kernel-module-management/internal/auth"
 	"github.com/kubernetes-sigs/kernel-module-management/internal/build"
 	"github.com/kubernetes-sigs/kernel-module-management/internal/daemonset"
 	"github.com/kubernetes-sigs/kernel-module-management/internal/filter"
 	"github.com/kubernetes-sigs/kernel-module-management/internal/metrics"
 	"github.com/kubernetes-sigs/kernel-module-management/internal/module"
+	"github.com/kubernetes-sigs/kernel-module-management/internal/registry"
 	"github.com/kubernetes-sigs/kernel-module-management/internal/statusupdater"
 	appsv1 "k8s.io/api/apps/v1"
 	batchv1 "k8s.io/api/batch/v1"
@@ -52,6 +54,7 @@ type ModuleReconciler struct {
 	daemonAPI        daemonset.DaemonSetCreator
 	kernelAPI        module.KernelMapper
 	metricsAPI       metrics.Metrics
+	registry         registry.Registry
 	filter           *filter.Filter
 	statusUpdaterAPI statusupdater.ModuleStatusUpdater
 }
@@ -63,6 +66,7 @@ func NewModuleReconciler(
 	kernelAPI module.KernelMapper,
 	metricsAPI metrics.Metrics,
 	filter *filter.Filter,
+	registry registry.Registry,
 	statusUpdaterAPI statusupdater.ModuleStatusUpdater) *ModuleReconciler {
 	return &ModuleReconciler{
 		Client:           client,
@@ -71,6 +75,7 @@ func NewModuleReconciler(
 		kernelAPI:        kernelAPI,
 		metricsAPI:       metricsAPI,
 		filter:           filter,
+		registry:         registry,
 		statusUpdaterAPI: statusUpdaterAPI,
 	}
 }
@@ -229,8 +234,14 @@ func (r *ModuleReconciler) handleBuild(ctx context.Context,
 	if mod.Spec.ModuleLoader.Container.Build == nil && km.Build == nil {
 		return false, nil
 	}
+	exists, err := r.checkImageExists(ctx, mod, km)
+	if err != nil {
+		return false, fmt.Errorf("failed to check image existence for kernel %s: %w", kernelVersion, err)
+	}
+	if exists {
+		return false, nil
+	}
 
-	// [TODO] check access to the image - execute build only if needed (image is inaccessible)
 	logger := log.FromContext(ctx).WithValues("kernel version", kernelVersion, "image", km.ContainerImage)
 	buildCtx := log.IntoContext(ctx, logger)
 
@@ -249,6 +260,23 @@ func (r *ModuleReconciler) handleBuild(ctx context.Context,
 	return buildRes.Requeue, nil
 }
 
+func (r *ModuleReconciler) checkImageExists(ctx context.Context, mod *kmmv1beta1.Module, km *kmmv1beta1.KernelMapping) (bool, error) {
+	var registryAuthGetter auth.RegistryAuthGetter
+	if irs := mod.Spec.ImageRepoSecret; irs != nil {
+		namespacedName := types.NamespacedName{
+			Name:      irs.Name,
+			Namespace: mod.Namespace,
+		}
+		registryAuthGetter = auth.NewRegistryAuthGetter(r.Client, namespacedName)
+	}
+	pullOptions := module.GetRelevantPullOptions(mod, km)
+	imageAvailable, err := r.registry.ImageExists(ctx, km.ContainerImage, pullOptions, registryAuthGetter)
+	if err != nil {
+		return false, fmt.Errorf("could not check if the image is available: %v", err)
+	}
+	return imageAvailable, nil
+}
+
 func (r *ModuleReconciler) handleDriverContainer(ctx context.Context,
 	mod *kmmv1beta1.Module,
 	km *kmmv1beta1.KernelMapping,