remote/index_options: create new index with IndexManifest

Signed-off-by: Husni Faiz <[email protected]>

remote/index_options.go

@@ -2,12 +2,14 @@ package remote
 
 import (
 	"github.com/buildpacks/imgutil"
+	v1 "github.com/google/go-containerregistry/pkg/v1"
 )
 
 type ImageIndexOption func(*indexOptions) error
 
 type indexOptions struct {
 	mediaTypes imgutil.MediaTypes
+	manifest   v1.IndexManifest
 }
 
 // WithIndexMediaTypes loads an existing index as a source.
@@ -18,3 +20,10 @@ func WithIndexMediaTypes(requested imgutil.MediaTypes) ImageIndexOption {
 		return nil
 	}
 }
+
+func WithManifest(manifest v1.IndexManifest) ImageIndexOption {
+	return func(opts *indexOptions) error {
+		opts.manifest = manifest
+		return nil
+	}
+}

remote/new_manifest_list.go

@@ -23,6 +23,31 @@ func NewIndex(repoName string, keychain authn.Keychain, ops ...ImageIndexOption)
 		}
 	}
 
+	if len(indexOpts.manifest.Manifests) != 0 {
+		index, err := emptyIndex(indexOpts.manifest.MediaType)
+		if err != nil {
+			return nil, err
+		}
+
+		for _, manifest_i := range indexOpts.manifest.Manifests {
+			img, _ := emptyImage(imgutil.Platform{
+				Architecture: manifest_i.Platform.Architecture,
+				OS:           manifest_i.Platform.OS,
+				OSVersion:    manifest_i.Platform.OSVersion,
+			})
+			index = mutate.AppendManifests(index, mutate.IndexAddendum{Add: img, Descriptor: manifest_i})
+		}
+
+		idx := &ImageIndex{
+			keychain: keychain,
+			repoName: repoName,
+			index:    index,
+		}
+
+		return idx, nil
+
+	}
+
 	mediaType := defaultMediaType()
 	if indexOpts.mediaTypes.IndexManifestType() != "" {
 		mediaType = indexOpts.mediaTypes