in src/main/scala/com/gu/ssm/utils/FilePermissions.scala [55:64]
def permissionAsString(perm: Int): String = perm match {
case 0 => "---"
case 1 => "--x"
case 2 => "-w-"
case 3 => "-wx"
case 4 => "r--"
case 5 => "r-x"
case 6 => "rw-"
case 7 => "rwx"
}