TransformerService.php
<?php
namespace Automattic\WooCommerce\Admin\RemoteSpecs\RuleProcessors\Transformers;
use InvalidArgumentException;
use stdClass;
/**
* A simple service class for the Transformer classes.
*
* Class TransformerService
*
* @package Automattic\WooCommerce\Admin\RemoteSpecs\RuleProcessors\Transformers
*/
class TransformerService {
/**
* Create a transformer object by name.
*
* @param string $name name of the transformer.
*
* @return TransformerInterface|null
*/
public static function create_transformer( $name ) {
$camel_cased = str_replace( ' ', '', ucwords( str_replace( '_', ' ', $name ) ) );
$classname = __NAMESPACE__ . '\\' . $camel_cased;
if ( ! class_exists( $classname ) ) {
return null;
}
return new $classname();
}
/**
* Apply transformers to the given value.
*
* @param mixed $target_value a value to transform.
* @param array $transformer_configs transform configuration.
* @param bool $is_default_set flag on is default value set.
* @param string $default_value default value.
*
* @throws InvalidArgumentException Throws when one of the requried arguments is missing.
* @return mixed|null
*/
public static function apply( $target_value, array $transformer_configs, $is_default_set, $default_value ) {
foreach ( $transformer_configs as $transformer_config ) {
if ( ! isset( $transformer_config->use ) ) {
throw new InvalidArgumentException( 'Missing required config value: use' );
}
if ( ! isset( $transformer_config->arguments ) ) {
$transformer_config->arguments = null;
}
$transformer = self::create_transformer( $transformer_config->use );
if ( null === $transformer ) {
throw new InvalidArgumentException( "Unable to find a transformer by name: {$transformer_config->use}" ); // phpcs:ignore WordPress.Security.EscapeOutput.ExceptionNotEscaped
}
$target_value = $transformer->transform( $target_value, $transformer_config->arguments, $is_default_set ? $default_value : null );
// Break early when there's no more value to traverse.
if ( null === $target_value ) {
break;
}
}
if ( $is_default_set ) {
// Nulls always return the default value.
if ( null === $target_value ) {
return $default_value;
}
// When type of the default value is different from the target value, return the default value
// to ensure type safety.
if ( gettype( $default_value ) !== gettype( $target_value ) ) {
return $default_value;
}
}
return $target_value;
}
}