add: override artifactType

pkg/mutate/image.go

@@ -17,11 +17,12 @@ import (
 )
 
 type image struct {
-	base               v1.Image
-	overrides          []v1.Layer
-	history            *v1.History
-	configFileOverride any
-	configTypeOverride types.MediaType
+	base                 v1.Image
+	overrides            []v1.Layer
+	history              *v1.History
+	configFileOverride   any
+	configTypeOverride   types.MediaType
+	artifactTypeOverride string
 
 	computed      bool
 	diffIDs       []v1.Hash
@@ -86,6 +87,7 @@ func (img *image) populate() error {
 
 	configFile := img.configFileOverride
 	configType := img.configTypeOverride
+	artifactType := img.artifactTypeOverride
 
 	// If configFile is not overridden, populate from the base image.
 	if configFile == nil {
@@ -151,6 +153,10 @@ func (img *image) populate() error {
 		manifest.Config.Data = config
 	}
 
+	if artifactType != "" {
+		manifest.Config.ArtifactType = artifactType
+	}
+
 	img.computed = true
 	img.diffIDs = diffIDs
 	img.byDiffID = byDiffID

pkg/mutate/mutate.go

@@ -79,6 +79,14 @@ func SetConfig(configFile any, configType types.MediaType) Mutation {
 	}
 }
 
+// SetArtifactType replaces the artifact type with the specified value.
+func SetArtifactType(artifactType string) Mutation {
+	return func(img *image) error {
+		img.artifactTypeOverride = artifactType
+		return nil
+	}
+}
+
 // Apply performs the specified mutation(s) to a base image, returning the resulting image.
 func Apply(base v1.Image, ms ...Mutation) (v1.Image, error) {
 	if len(ms) == 0 {

pkg/mutate/mutate_test.go

@@ -71,6 +71,21 @@ func TestApply(t *testing.T) {
 				SetConfig(&v1.ConfigFile{Author: "Author"}, types.DockerConfigJSON),
 			},
 		},
+		{
+			name: "SetConfigEmpty",
+			base: img,
+			ms: []Mutation{
+				SetConfig(struct{}{}, "application/vnd.oci.empty.v1+json"),
+			},
+		},
+		{
+			name: "SetArtifactType",
+			base: img,
+			ms: []Mutation{
+				SetConfig(struct{}{}, "application/vnd.oci.empty.v1+json"),
+				SetArtifactType("application/vnd.sylabs.container"),
+			},
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {

pkg/mutate/testdata/TestApply/SetArtifactType/config.golden

@@ -0,0 +1 @@
+{}

pkg/mutate/testdata/TestApply/SetArtifactType/manifest.golden

@@ -0,0 +1 @@
+{"schemaVersion":2,"mediaType":"application/vnd.docker.distribution.manifest.v2+json","config":{"mediaType":"application/vnd.oci.empty.v1+json","size":2,"digest":"sha256:44136fa355b3678a1146ad16f7e8649e94fb4fc21fe77e8310c060f61caaff8a","artifactType":"application/vnd.sylabs.container"},"layers":[{"mediaType":"application/vnd.docker.image.rootfs.diff.tar.gzip","size":3208,"digest":"sha256:7050e35b49f5e348c4809f5eff915842962cb813f32062d3bbdd35c750dd7d01"}]}

pkg/mutate/testdata/TestApply/SetConfigEmpty/config.golden

@@ -0,0 +1 @@
+{}

pkg/mutate/testdata/TestApply/SetConfigEmpty/manifest.golden

@@ -0,0 +1 @@
+{"schemaVersion":2,"mediaType":"application/vnd.docker.distribution.manifest.v2+json","config":{"mediaType":"application/vnd.oci.empty.v1+json","size":2,"digest":"sha256:44136fa355b3678a1146ad16f7e8649e94fb4fc21fe77e8310c060f61caaff8a"},"layers":[{"mediaType":"application/vnd.docker.image.rootfs.diff.tar.gzip","size":3208,"digest":"sha256:7050e35b49f5e348c4809f5eff915842962cb813f32062d3bbdd35c750dd7d01"}]}