Magento – Magento 2 : Use plugin / interceptor on abstract class

Plugins are sorted by sort order first, and then by method prefix.

Example: for method with 3 plugins (PluginA, PluginB, PluginC) with following methods and sortOrder:

• PluginA (sortOrder = 10)
  • beforeDispatch()
  • afterDispatch()
• PluginB (sortOrder = 20)
  • beforeDispatch()
  • aroundDispatch()
  • afterDispatch()
• PluginC (sortOrder = 30):
  • beforeDispatch()
  • aroundDispatch()
  • afterDispatch()

Execution flow should be following:

• PluginA::beforeDispatch()
• PluginB::beforeDispatch()
• PluginB::aroundDispatch()
  • PluginC::beforeDispatch()
  • PluginC::aroundDispatch()
    • Action::dispatch()
  • PluginC::afterDispatch()
• PluginB::afterDispatch()
• PluginA::afterDispatch()

This is because the controller object does not contain the order and you are trying to call getOrder() on it. Magento dispatches an observer for this purpose, sales_order_place_after, and you can grab the order there. There are a variety of plugins that could be created for this purpose but the observer mentioned above is easiest.

If you only want this to occur for orders placed through the admin panel, you could implement a plugin for Magento\Sales\Model\AdminOrder\Create with the method afterCreateOrder($subject,$result). The $result variable will contain the actual order.