fix: Also request OCI media type image index (#524)

Signed-off-by: jannfis <jann@mistrust.net>

Signed-off-by: jannfis <jann@mistrust.net>

Author: jannfis

go.mod

@@ -11,6 +11,7 @@ require (
 	github.com/distribution/distribution/v3 v3.0.0-20221208165359-362910506bc2
 	github.com/go-git/go-git/v5 v5.2.0
 	github.com/opencontainers/go-digest v1.0.0
+	github.com/opencontainers/image-spec v1.0.2
 	github.com/patrickmn/go-cache v2.1.0+incompatible
 	github.com/prometheus/client_golang v1.12.1
 	github.com/sirupsen/logrus v1.8.1
@@ -110,7 +111,6 @@ require (
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/modern-go/reflect2 v1.0.2 // indirect
 	github.com/monochromegane/go-gitignore v0.0.0-20200626010858-205db1a8cc00 // indirect
-	github.com/opencontainers/image-spec v1.0.2 // indirect
 	github.com/peterbourgon/diskv v2.0.1+incompatible // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect

pkg/registry/client.go

@@ -24,6 +24,7 @@ import (
 	"github.com/distribution/distribution/v3/registry/client/transport"
 
 	"github.com/opencontainers/go-digest"
+	ociv1 "github.com/opencontainers/image-spec/specs-go/v1"
 
 	"go.uber.org/ratelimit"
 
@@ -35,6 +36,15 @@ import (
 
 // TODO: Check image's architecture and OS
 
+// knownMediaTypes is the list of media types we can process
+var knownMediaTypes = []string{
+	ocischema.SchemaVersion.MediaType,
+	schema1.MediaTypeSignedManifest,
+	schema2.SchemaVersion.MediaType,
+	manifestlist.SchemaVersion.MediaType,
+	ociv1.MediaTypeImageIndex,
+}
+
 // RegistryClient defines the methods we need for querying container registries
 type RegistryClient interface {
 	NewRepository(nameInRepository string) error
@@ -159,11 +169,10 @@ func (clt *registryClient) ManifestForTag(tagStr string) (distribution.Manifest,
 	if err != nil {
 		return nil, err
 	}
-	mediaType := []string{ocischema.SchemaVersion.MediaType, schema1.MediaTypeSignedManifest, schema2.SchemaVersion.MediaType, manifestlist.SchemaVersion.MediaType}
 	manifest, err := manService.Get(
 		context.Background(),
 		digest.FromString(tagStr),
-		distribution.WithTag(tagStr), distribution.WithManifestMediaTypes(mediaType))
+		distribution.WithTag(tagStr), distribution.WithManifestMediaTypes(knownMediaTypes))
 	if err != nil {
 		return nil, err
 	}
@@ -176,11 +185,10 @@ func (clt *registryClient) ManifestForDigest(dgst digest.Digest) (distribution.M
 	if err != nil {
 		return nil, err
 	}
-	mediaType := []string{ocischema.SchemaVersion.MediaType, schema1.MediaTypeSignedManifest, schema2.SchemaVersion.MediaType, manifestlist.SchemaVersion.MediaType}
 	manifest, err := manService.Get(
 		context.Background(),
 		dgst,
-		distribution.WithManifestMediaTypes(mediaType))
+		distribution.WithManifestMediaTypes(knownMediaTypes))
 	if err != nil {
 		return nil, err
 	}