class NodeModerationHandler

class NodeModerationHandler extends ModerationHandler {
    
    /**
     * The moderation information service.
     *
     * @var \Drupal\content_moderation\ModerationInformationInterface
     */
    protected $moderationInfo;
    
    /**
     * NodeModerationHandler constructor.
     *
     * @param \Drupal\content_moderation\ModerationInformationInterface $moderation_info
     *   The moderation information service.
     */
    public function __construct(ModerationInformationInterface $moderation_info) {
        $this->moderationInfo = $moderation_info;
    }
    
    /**
     * {@inheritdoc}
     */
    public static function createInstance(ContainerInterface $container, EntityTypeInterface $entity_type) {
        return new static($container->get('content_moderation.moderation_information'));
    }
    
    /**
     * {@inheritdoc}
     */
    public function enforceRevisionsEntityFormAlter(array &$form, FormStateInterface $form_state, $form_id) {
        $form['revision']['#disabled'] = TRUE;
        $form['revision']['#default_value'] = TRUE;
        $form['revision']['#description'] = $this->t('Revisions are required.');
    }
    
    /**
     * {@inheritdoc}
     */
    public function enforceRevisionsBundleFormAlter(array &$form, FormStateInterface $form_state, $form_id) {
        // Force the revision checkbox on.
        $form['workflow']['options']['revision']['#value'] = 'revision';
        $form['workflow']['options']['revision']['#disabled'] = TRUE;
    }

}