ConfigurableEventHandlerBase.php

<?php

namespace Drupal\rules\EventHandler;

use Drupal\Core\Form\FormStateInterface;
use Drupal\rules\Core\RulesConfigurableEventHandlerInterface;
use Drupal\rules\Core\RulesDefaultEventHandler;

/**
 * Base class for event handler.
 */
abstract class ConfigurableEventHandlerBase extends RulesDefaultEventHandler implements RulesConfigurableEventHandlerInterface {
    
    /**
     * The event configuration.
     *
     * @var array
     */
    protected $configuration = [];
    
    /**
     * {@inheritdoc}
     */
    public function extractConfigurationFormValues(array &$form, FormStateInterface $form_state) {
        foreach ($this->defaultConfiguration() as $key => $configuration) {
            $this->configuration[$key] = $form_state->hasValue($key) ? $form_state->getValue($key) : $configuration;
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public function getConfiguration() {
        return $this->configuration;
    }
    
    /**
     * {@inheritdoc}
     */
    public function setConfiguration(array $configuration) {
        $this->configuration = $configuration + $this->defaultConfiguration();
        return $this;
    }
    
    /**
     * {@inheritdoc}
     */
    public function defaultConfiguration() {
        return [];
    }

}