protected function parseConverterMap(array $objectSchema)
{
$converterMap = [];
if (array_key_exists('converters', $objectSchema)) {
foreach ($objectSchema['converters'] as $converter => $attributes) {
if (is_array($attributes)) {
foreach ($attributes as $attribute) {
$converterMap[$attribute] = $converter;
}
} elseif (is_string($attributes)) {
$converterMap[$attributes] = $converter;
}
}
}
return $converterMap;
}