How can you remove another modules events?

Question

So, I have an event subscriber for Drupal commerce that listens for "commerce_order.place.post_transition" and will send a bespoke order email (due to not being able to change some of the things like subject title in the commerce module).

Commerce also has an event subscriber listening to "commerce_order.place.post_transition" which will send an order receipt email. I need to unsubscribe this event to prevent sending duplicate emails but searching through google and comments sections of articles has lead me to a dead end.

Any ideas?

Answer 1

Remove the event subcriber service from the container:

my_module/src/MyModuleServiceProvider.php

namespace Drupal\my_module;

use Drupal\Core\DependencyInjection\ContainerBuilder;
use Drupal\Core\DependencyInjection\ServiceProviderBase;

/**
 * Remove the foo event subscriber.
 */
class MyModuleServiceProvider extends ServiceProviderBase {

  /**
   * {@inheritdoc}
   */
  public function alter(ContainerBuilder $container) {
    $container->removeDefinition('foo_event_subscriber'); 
  }

}

You find the service name in the MODULE.services.yml file of the other module.

More info https://www.drupal.org/docs/8/api/services-and-dependency-injection/altering-existing-services-providing-dynamic-services

Answer 2

This doesn't answer your question specifically but is an alternative. If it's the standard commerce email you could go to "Commerce > configuration > Orders > Order types" and within each order type you can control to "Email the customer a receipt when an order is placed"

Answer 3

Decorate the existing event as described in this article: https://matthieuscarset.com/en/blog/how-safely-override-or-extend-other-services-methods-drupal-8

In mymodule/src/EventSubscriber/MySubscriber.php:

namespace Drupal\mymodule\EventSubscriber;

class MySubscriber extends ParentSubscriber {

  /**
   * {@inheritDoc}
   */
  public function decoratedMethod(...$args) {
    parent::decoratedMethod(...$args); // or whatever you want to do
  }
}

In mymodule/mymodule.services.yml:

services:
  mymodule.myservice:
    public: false
    class: Drupal\mymodule\EventSubscriber\mySubscriber
    decorates: decorated_provider.decorated_service_name

Answer 4

and welcome to Drupal Answers.

Assuming you're using Drupal 8, you may try the below code to hide the email fieldset:

function mymodule_form_alter(&$form, \Drupal\Core\Form\FormStateInterface $form_state, $form_id) {
    if ($form_id == "commerce_order_type_edit_form") {
        $form["emails"] = [
            "#checked" => FALSE,
        ];
    }
}

Hope that helps.