cvo: refactor LoadUpdate

Extract loading tasks from `loadUpdatePayloadMetadata` one layer up to `LoadUpdate`, which makes more sense as a logical sequence of "loading the update". This also allows simplifying `loadUpdatePayloadMetadata` signature because the inputs for loading tasks are partially disjoint from the ones needed for loading the metadata.

Author: petr-muller

pkg/payload/payload.go

@@ -140,12 +140,22 @@ type metadata struct {
 
 func LoadUpdate(dir, releaseImage, excludeIdentifier string, requiredFeatureSet string, profile string,
 	knownCapabilities []configv1.ClusterVersionCapability) (*Update, error) {
+	klog.V(2).Infof("Loading updatepayload from %q", dir)
+	if err := ValidateDirectory(dir); err != nil {
+		return nil, err
+	}
+	var (
+		cvoDir     = filepath.Join(dir, CVOManifestDir)
+		releaseDir = filepath.Join(dir, ReleaseManifestDir)
+	)
 
-	payload, tasks, err := loadUpdatePayloadMetadata(dir, releaseImage, profile)
+	payload, err := loadPayloadMetadata(releaseDir, releaseImage)
 	if err != nil {
 		return nil, err
 	}
 
+	tasks := loadPayloadTasks(releaseDir, cvoDir, releaseImage, profile)
+
 	var onlyKnownCaps *configv1.ClusterVersionCapabilitiesStatus
 
 	if knownCapabilities != nil {
@@ -293,47 +303,36 @@ func ValidateDirectory(dir string) error {
 	return nil
 }
 
-type payloadTasks struct {
-	idir       string
-	preprocess func([]byte) ([]byte, error)
-	skipFiles  sets.Set[string]
-}
-
-func loadUpdatePayloadMetadata(dir, releaseImage, clusterProfile string) (*Update, []payloadTasks, error) {
-	klog.V(2).Infof("Loading updatepayload from %q", dir)
-	if err := ValidateDirectory(dir); err != nil {
-		return nil, nil, err
-	}
-	var (
-		cvoDir     = filepath.Join(dir, CVOManifestDir)
-		releaseDir = filepath.Join(dir, ReleaseManifestDir)
-	)
-
+func loadPayloadMetadata(releaseDir, releaseImage string) (*Update, error) {
 	release, arch, err := loadReleaseFromMetadata(releaseDir)
 	if err != nil {
-		return nil, nil, err
+		return nil, err
 	}
 	release.Image = releaseImage
 
 	imageRef, err := loadImageReferences(releaseDir)
 	if err != nil {
-		return nil, nil, err
+		return nil, err
 	}
 
 	if imageRef.Name != release.Version {
-		return nil, nil, fmt.Errorf("Version from %s (%s) differs from %s (%s)", imageReferencesFile, imageRef.Name, cincinnatiJSONFile, release.Version)
+		return nil, fmt.Errorf("Version from %s (%s) differs from %s (%s)", imageReferencesFile, imageRef.Name, cincinnatiJSONFile, release.Version)
 	}
 
-	tasks := getPayloadTasks(releaseDir, cvoDir, releaseImage, clusterProfile)
-
 	return &Update{
 		Release:      release,
 		ImageRef:     imageRef,
 		Architecture: arch,
-	}, tasks, nil
+	}, nil
+}
+
+type payloadTasks struct {
+	idir       string
+	preprocess func([]byte) ([]byte, error)
+	skipFiles  sets.Set[string]
 }
 
-func getPayloadTasks(releaseDir, cvoDir, releaseImage, clusterProfile string) []payloadTasks {
+func loadPayloadTasks(releaseDir, cvoDir, releaseImage, clusterProfile string) []payloadTasks {
 	cjf := filepath.Join(releaseDir, cincinnatiJSONFile)
 	irf := filepath.Join(releaseDir, imageReferencesFile)