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;
    }