Support skipping artifacts synchronization

README.md

@@ -8,6 +8,7 @@ Sync chart packages and associated container images between chart repositories
     + [Sync all charts](#sync-all-helm-charts)
     + [Sync all charts from specific date](#sync-all-charts-from-specific-date)
 - [Advanced Usage](#advanced-usage)
+    + [Skip syncing artifacts](#skip-syncing-artifacts)
     + [Sync only specific container platforms](#sync-only-specific-container-platforms)
     + [Sync Helm Charts and Container Images to different registries](#sync-helm-charts-and-container-images-to-different-registries)
     + [Sync charts between repositories without direct connectivity](#sync-charts-between-repositories-without-direct-connectivity)
@@ -75,6 +76,44 @@ charts:
   - mariadb
 ```
 
+### Skip syncing artifacts
+
+If your chart and docker images include artifacts such as signatures or metadata, they will be synced to the destination repository. If you want to disable this behavior, you can opt out by setting `skipArtifacts` to true:
+
+```yaml
+source:
+  repo:
+    kind: OCI
+    url: http://localhost:8080
+target:
+  repo:
+    kind: OCI
+    url: http://localhost:9090/charts
+charts:
+  - redis
+
+skipArtifacts: true
+```
+
+This is especially useful when you filter the container platforms to sync, which would invalidate the signatures. Using `skipArtifacts: true` will prevent syncing the now invalid signatures:
+
+```yaml
+source:
+  repo:
+    kind: OCI
+    url: http://localhost:8080
+target:
+  repo:
+    kind: OCI
+    url: http://localhost:9090/charts
+charts:
+  - redis
+skipArtifacts: true
+containerPlatforms:
+  - linux/amd64
+```
+
+
 ### Sync Helm Charts and Container Images to different registries
 
 By default, charts-syncer syncs Helm Charts packages and their container images to the same registry specified in the `target.repo.url` property. If you require to configure a different destination registry for the images, this can be configured in the `target.containers.url` property:

api/config.proto

@@ -13,6 +13,9 @@ message Config {
     repeated string container_platforms = 4;
     // Opposite of charts property. It indicates the list of charts to skip during sync
     repeated string skip_charts = 5;
+    // Do not sync chart and container artifacts (signatures and metadata)
+    bool skip_artifacts = 6;
+
 }
 
 // SourceRepo contains the required information of the source chart repository

cmd/sync.go

@@ -106,6 +106,7 @@ func newSyncCmd() *cobra.Command {
 				syncer.WithContainerPlatforms(c.GetContainerPlatforms()),
 				syncer.WithInsecure(rootInsecure),
 				syncer.WithLatestVersionOnly(syncLatestVersionOnly),
+				syncer.WithSkipArtifacts(c.GetSkipArtifacts()),
 				syncer.WithSkipCharts(c.SkipCharts),
 				syncer.WithUsePlainHTTP(usePlainHTTP),
 				syncer.WithLogger(l),

pkg/client/config/config.go

@@ -11,6 +11,7 @@ type Config struct {
 	Logger             log.SectionLogger
 	WorkDir            string
 	ContainerPlatforms []string
+	SkipArtifacts      bool
 }
 
 // Option is a function that modifies the Config
@@ -23,6 +24,13 @@ func WithWorkDir(workdir string) func(*Config) {
 	}
 }
 
+// WithSkipArtifacts sets the skip artifacts flag
+func WithSkipArtifacts(skipArtifacts bool) func(*Config) {
+	return func(c *Config) {
+		c.SkipArtifacts = skipArtifacts
+	}
+}
+
 // WithContainerPlatforms sets the container platforms to sync
 func WithContainerPlatforms(containerPlatforms []string) func(*Config) {
 	return func(c *Config) {

pkg/client/source/common/common.go

@@ -50,7 +50,9 @@ func (t *Source) Wrap(tgz, destWrap string, opts ...config.Option) (string, erro
 	}
 	defer os.RemoveAll(wrapWorkdir)
 
-	outputFile, err := wrap.Chart(tgz, wrap.WithFetchArtifacts(true),
+	fetchArtifacts := !cfg.SkipArtifacts
+
+	outputFile, err := wrap.Chart(tgz, wrap.WithFetchArtifacts(fetchArtifacts),
 		wrap.WithInsecure(t.insecure), wrap.WithTempDirectory(wrapWorkdir),
 		wrap.WithAuth(t.username, t.password),
 		wrap.WithPlatforms(cfg.ContainerPlatforms),

pkg/syncer/sync.go

@@ -43,7 +43,8 @@ func (s *Syncer) syncChart(ch *Chart, l log.SectionLogger) error {
 
 	wrappedChartPath, err := s.cli.src.Wrap(ch.TgzPath,
 		filepath.Join(workdir, "wraps", fmt.Sprintf("%s-%s.wrap.tgz", ch.Name, ch.Version)),
-		config.WithLogger(l), config.WithWorkDir(workdir), config.WithContainerPlatforms(s.containerPlatforms),
+		config.WithLogger(l), config.WithWorkDir(workdir),
+		config.WithContainerPlatforms(s.containerPlatforms), config.WithSkipArtifacts(s.skipArtifacts),
 	)
 	if err != nil {
 		return errors.Annotatef(err, "unable to move chart %q with charts-syncer", id)

pkg/syncer/syncer.go

@@ -45,6 +45,9 @@ type Syncer struct {
 	// up re-runs
 	index ChartIndex
 
+	// skip syncing artifacts
+	skipArtifacts bool
+
 	// Storage directory for required artifacts
 	workdir string
 
@@ -91,6 +94,13 @@ func WithUsePlainHTTP(enable bool) Option {
 	}
 }
 
+// WithSkipArtifacts configures the syncer to skip syncing artifacts
+func WithSkipArtifacts(skip bool) Option {
+	return func(s *Syncer) {
+		s.skipArtifacts = skip
+	}
+}
+
 // WithWorkdir configures the syncer to store artifacts in a specific directory.
 func WithWorkdir(dir string) Option {
 	return func(s *Syncer) {