Building a Chat Plugin for Shopware 6: Message Queues, Sales Channels, and Service Decoration

I already had webhook sync modules for Drupal Commerce, Sylius, and PrestaShop. Shopware 6 is the most complex of the four: sales channels, multi-currency, Symfony Messenger for async, and a Vue.js admin framework.

Shopware's Event Subscriber System

Shopware uses event subscribers similar to Sylius (both are Symfony-based), but with Shopware-specific event classes:

class ProductSubscriber implements EventSubscriberInterface

{