Symfony inject EntityManager in SwitchUserListener

Question

My question is about how to inject the entity manager in the SwitchUserListener that already has 9 parameters.

I have a custom switch user flow where I need to set the ExternalClient passed along with the _switch_user parameter (?_switch_user=user1&external_client_id=1) in the session. I first have to fetch the ExternalClient from the database before I can set it.

In parameters.yml I've added

security.authentication.switchuser_listener.class: App\Bundle\Listener\SwitchUserListener

And for the content of App\Bundle\Listener\SwitchUserListener I used the Symfony SwitchUserListener Symfony\Component\Security\Http\Firewall\SwitchUserListener.php

Everything works and when I fetch the external_client_id parameter from the request variable in the listener it is populated. But I can't seem to get access to the entity manager.

Things I've tried:

1. Add decorator in services.yml

   app.decorating_switch_user:
     class:     App\Bundle\Listener\SwitchUserListener
     decorates: security.authentication.switchuser_listener
     arguments: ['@app.decorating_switch_user.inner', '@doctrine.orm.entity_manager']
     public:    false
   

2. Overriding parent dependencies in services.yml

   security.authentication.switchuser_listener:
     abstract:  true
   
   test:
     class: "%security.authentication.switchuser_listener.class%"
     parent: security.authentication.switchuser_listener
     public: false
     # appends the '@doctrine.orm.entity_manager' argument to the parent
     # argument list
     arguments: ['@doctrine.orm.entity_manager']
   

3. Listen to SwitchUserEvent instead

    app.switch_user_listener:
      class: App\Bundle\Listener\SwitchUserListener
      tags:
         - { name: kernel.event_listener, event: security.switch_user, method: onSwitchUser }
   

   Here I've replace the contents of 'App\Bundle\Listener\SwitchUserListener' with:

   class SwitchUserListener
   {
       public function onSwitchUser(SwitchUserEvent $event)
       {
           $request = $event->getRequest();
           echo "<pre>";
           dump($externalClientId = $request->get('external_client_id'));
           echo "</pre>";
           exit;
       }
   }
   

   I'm getting the external_client_id as well with this attempt but I have no idea how to inject the entity manager. And even If I did, I'd have no way of getting the original user that initiated the _switch_user request. SwitchUserEvent only has access to the getTargetUser() method.

Conclusion:

If anybody has experience with this topic and is willing to share it that would be great. Ideally I would add the entity manager service to the previous 9 arguments of the __construct function. I'm expanding that class just like Matt is doing here: Symfony2: Making impersonating a user more friendly

Answer 1

You can override the service as follows. You may need to look up/change the concrete order of service arguments as it changed between symfony versions. Some arguments like $providerKey can be left empty as they will be changed/injected automatically by symfony.

In order to save some time coding you won't need to override the constructor if you use setter injection.

A look at Symfony's default SwitchUserListener (switch to the tag/version used in your application) will help when implementing your new handle method.

# app/config/services.yml
services:
  # [..]
  security.authentication.switchuser_listener:
    class: 'Your\Namespace\SwitchUserListener'
    public: false
    abstract: true
    arguments: 
      - '@security.context'
      - ~
      - '@security.user_checker' 
      - ~
      - '@security.access.decision_manager' 
      - '@?logger' 
      - '_switch_user' 
      - ~
      - '@?event_dispatcher' 
      - ~
    calls:
      - [ 'setEntityManager', [ '@doctrine.orm.entity_manager' ]]
    tags:
      - { name: monolog.logger, channel: security }

Now your SwitchUserListener might look like this:

namespace Your\Namespace;

use Symfony\Component\Security\Http\Firewall\SwitchUserListener as DefaultListener;
use Doctrine\ORM\EntityManagerInterface;
use Symfony\Component\HttpKernel\Event\GetResponseEvent;

class SwitchUserListener extends DefaultListener
{
    /** @var EntityManagerInterface */
    protected $em;

    public function setEntityManager(EntityManagerInterface $em)
    {
        $this->em = $em;
    }

    /**
     * Handles the switch to another user.
     *
     * @throws \LogicException if switching to a user failed
     */
     public function handle(GetResponseEvent $event)
     {
          // Do your custom switching logic here
     }
}

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