fix: support different type of registry response

client/registry.go

@@ -116,7 +116,7 @@ func GetTagDigest(image reference.Named) (string, error) {
 		return "", err
 	}
 
-	registryRes := struct {
+	registryResT1 := struct {
 		SchemaVersion int
 		MediaType     string
 		Manifests     []struct {
@@ -130,17 +130,39 @@ func GetTagDigest(image reference.Named) (string, error) {
 		}
 	}{}
 
-	if err := json.Unmarshal(body, &registryRes); err != nil {
+	registryResT2 := struct {
+		SchemaVersion int
+		MediaType     string
+		Config        struct {
+			MediaType string
+			Size      int
+			Digest    string
+		}
+		Layers []struct {
+			MediaType string
+			Size      int
+			Digest    string
+		}
+	}{}
+
+	if err := json.Unmarshal(body, &registryResT1); err != nil {
 		return "", err
 	}
 
 	var digest string
-	for _, manifest := range registryRes.Manifests {
+	for _, manifest := range registryResT1.Manifests {
 		if string(manifest.Platform.Architecture) == "amd64" {
 			digest = strings.Split(manifest.Digest, ":")[1][:7]
 		}
 	}
 
+	if digest == "" {
+		if err := json.Unmarshal(body, &registryResT2); err != nil {
+			return "", err
+		}
+		digest = strings.Split(registryResT2.Config.Digest, ":")[1][:7]
+	}
+
 	if digest == "" {
 		return "", fmt.Errorf("Unable to retrieve amd64 digest for '%s'", image)
 	}