Zend framework 2: Define a method available in all controllers - zend-framework

Question

How do I have a method, defined once, available in all controllers?
In my UsersController app I have a method called getAuthService (which fetches the authentication service), but I want to be able to access the authentication instance from other controller too (so I can access it's storage). Below is my method in UsersController:
class UsersController {
protected $authService
.
.
.
protected function getAuthService() {
if (! $this->authService) {
$dbAdapter = $this->getServiceLocator()->get('\Zend\Db\Adapter\Adapter');
$dbTableAuthAdapter = new DbTableAuthAdapter($dbAdapter, 'users', 'email', 'password', 'MD5(?)');
$authService = new AuthenticationService();
$authService->setAdapter($dbTableAuthAdapter);
$this->authService = $authService;
}
return $this->authService;
}
}
.. however, I cannot access this in my ApplicationController unless I copy the method in there? Can I define this method somewhere else? Or, another way?
In Rails I'd put this method into the application controller as other controllers extend from that. Is it the Zend way to create a controller containing shared methods that extends AbstractActionController and other controllers extend from that, or extend other modules' controllers from the Application\Controller\IndexController:
- Zend\Mvc\Controller\AbstractActionController (abstract)
- Application\Controller\IndexController (containing my getAuthService method)
- Users\Controller\UsersController (extends the above so getAuthService is available)
Thanks

Answer 1

You could write a Controller Plugin. Since you require the authservice aswell as the dbadapter it probably is a good idea to write a factory which retrieves those. Within your application/src/Controller we add a folder called Plugin. Once that is done we create our factory which fetches the required services etc.
namespace Application\Controller\Plugin;
use Zend\ServiceManager\FactoryInterface;
use Zend\ServiceManager\ServiceLocatorInterface;
/**
*
* Your factory
*
* #package Application
*/
class AuthFactory implements FactoryInterface
{
/**
* Create Service Factory
*
* #param ServiceLocatorInterface $serviceLocator
*/
public function createService(ServiceLocatorInterface $serviceLocator)
{
$sm = $serviceLocator->getServiceLocator();
$adapter = $sm->get('\Zend\Db\Adapter\Adapter');
$plugin = new Auth();
$plugin->setAdapter($adapter);
return $plugin;
}
}
The Plugin could be something like following:
namespace Application\Controller\Plugin;
use Zend\Mvc\Controller\Plugin\AbstractPlugin;
class Auth extends AbstractPlugin
{
protected $adapter;
protected $authService;
public function setAdapter($adapter)
{
$this->adapter = $adapter;
}
public function getAdapter()
{
return $this->adapter;
}
public function getService()
{
if (! $this->authService) {
$dbAdapter = $this->getAdapter();
$dbTableAuthAdapter = new DbTableAuthAdapter($dbAdapter, 'users', 'email', 'password', 'MD5(?)');
$authService = new AuthenticationService();
$authService->setAdapter($dbTableAuthAdapter);
$this->authService = $authService;
}
return $this->authService;
}
}
Now we have to add our factory to the module.config file like so:
'controller_plugins' => array(
'factories' => array(
'auth' => 'Application\Controller\Plugin\AuthFactory',
),
),
Once that is done you can just call your controller plugin within the controller like so:
$this->auth()->getService();
//or the alternative syntax
$this->plugin('auth')->getService();