RequirementsException.php

<?php

namespace Drupal\migrate\Exception;

use Exception;

/**
 * Defines an exception thrown when a migration does not meet the requirements.
 *
 * @see \Drupal\migrate\Plugin\RequirementsInterface
 */
class RequirementsException extends \RuntimeException {
    
    /**
     * The missing requirements.
     *
     * @var array
     */
    protected $requirements;
    
    /**
     * Constructs a new RequirementsException instance.
     *
     * @param string $message
     *   (optional) The Exception message to throw.
     * @param array $requirements
     *   (optional) The missing requirements.
     * @param int $code
     *   (optional) The Exception code.
     * @param \Exception $previous
     *   (optional) The previous exception used for the exception chaining.
     */
    public function __construct($message = "", array $requirements = [], $code = 0, Exception $previous = NULL) {
        parent::__construct($message, $code, $previous);
        $this->requirements = $requirements;
    }
    
    /**
     * Get an array of requirements.
     *
     * @return array
     *   The requirements.
     */
    public function getRequirements() {
        return $this->requirements;
    }
    
    /**
     * Get the requirements as a string.
     *
     * @return string
     *   A formatted requirements string.
     */
    public function getRequirementsString() {
        $output = '';
        foreach ($this->requirements as $requirement_type => $requirements) {
            if (!is_array($requirements)) {
                $requirements = [
                    $requirements,
                ];
            }
            foreach ($requirements as $value) {
                $output .= "{$requirement_type}: {$value}. ";
            }
        }
        return trim($output);
    }

}