How to create a new Selection Rule(Condition) for Panels in Drupal 8

SubscriptionIsActive.php

<?php
/**
 * Created by PhpStorm.
 * User: Lex
 * Date: 23.12.2017
 * Time: 6:52
 */

namespace Drupal\housing\Plugin\Condition;

use Drupal\Core\Condition\ConditionPluginBase;
use Drupal\housing\Entity\HousingInterface;

/**
 * Provides a 'Subscription Is Active' condition.
 *
 * @Condition(
 *   id = "subscription_is_active",
 *   label = @Translation("Subscription Is Active"),
 *   category = @Translation("Housing"),
 *   context = {
 *     "housing" = @ContextDefinition("entity:housing",
 *       label = @Translation("Housing")
 *     )
 *   }
 * )
 *
 */
class SubscriptionIsActive extends ConditionPluginBase{

  /**
   * @inheritDoc
   */
  public function evaluate() {
    $pass = FALSE;
    /** @var \Drupal\housing\Entity\HousingInterface $housing */
    $housing = $this->getContextValue('housing');
    if (!$housing instanceof HousingInterface) {
      return $pass;
    }

    if(!$housing->getSubscription()) {
      return $pass;
    }

    $subscription = $housing->getSubscription();
    $pass = $subscription->isActive();
    return $pass;
  }

  /**
   * @inheritDoc
   */
  public function summary() {
    return $this->t('The TRUE if Subscription is active.');
  }


}