[#1190] ape: Introduce Groups util function to retrieve actor's groupIDs

Signed-off-by: Airat Arifullin <a.arifullin@yadro.com>

pkg/ape/request/frostfsid.go

@@ -34,3 +34,19 @@ func FormFrostfsIDRequestProperties(frostFSIDClient frostfsidcore.SubjectProvide
 
 	return reqProps, nil
 }
+
+// Groups return the actor's group ids from frostfsid contract.
+func Groups(frostFSIDClient frostfsidcore.SubjectProvider, pk *keys.PublicKey) ([]string, error) {
+	subj, err := frostFSIDClient.GetSubjectExtended(pk.GetScriptHash())
+	if err != nil {
+		if !strings.Contains(err.Error(), frostfsidcore.SubjectNotFoundErrorMessage) {
+			return nil, fmt.Errorf("get subject error: %w", err)
+		}
+		return []string{}, nil
+	}
+	groups := make([]string, len(subj.Groups))
+	for i, group := range subj.Groups {
+		groups[i] = strconv.FormatInt(group.ID, 10)
+	}
+	return groups, nil
+}