events.md

Events

Like Symfony, The AdminBundle use events to gather data in order to build the Admin view can be customized using events. Here is a list of all available events to help you to finely customize your Admin. The list is available in the LAG\AdminBundle\Event\Events class.

ADMIN_HANDLE_REQUEST

This event is dispatched when an Admin route is called. It is responsible for build the current Action (list, edit...), and to set this Action in the event. It also in charge of checking if the current User is allowed to see a view or to do an action.

You can set an Action to this event, and get the current Admin object.

Changing the current Action class

You can change the current Action class using the ADMIN_HANDLE_REQUEST event :

use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use LAG\AdminBundle\Event\EventsOLD;
use LAG\AdminBundle\Event\EventsOLD\AdminEvent;


class MySubscriber implements EventSubscriberInterface
{
    public static function getSubscribedEvents()
    {
        return [
            Events::ADMIN_HANDLE_REQUEST => 'handleRequest',
        ];
    }
    
    public function handleRequest(AdminEvent $event): void
    {
        // Get the current Admin object
        $admin = $event->getAdmin();
        
        // For instance, create an action according to the Admin name
        if ($admin->getName() === 'my_custom_name') {
            // Create a new Action object implementing LAG\AdminBundle\Admin\ActionInterface
            // $action = ...     
        }
        $event->setAction($action);
        
        // Latter in the code (when this event dispatched), you can use $admin->getCurrentAction() and your Action object will be returned
    }
}

Denying access for the current user

The AdminBundle use Symfony roles to check permissions. It can be configured the Admin configuration or for each Action, using the following configuration :

my_admin:
    # This permissions are checked for each Actions in the Admin
    permissions: [ROLE_MY_ADMIN_ROLE]
    actions:
        list:
            # Only users with this role can see the list of entities
            permissions: [ROLE_MY_ACTION_ROLE]

By convention, roles in Symfony starts with ROLE_.

You can also deny access using your custom code to check permissions. Here is an example :

use LAG\AdminBundle\Application\Configuration\ApplicationConfiguration;use LAG\AdminBundle\Configuration\ApplicationConfigurationStorage;use LAG\AdminBundle\Event\EventsOLD;use LAG\AdminBundle\Event\EventsOLD\AdminEvent;use Symfony\Component\EventDispatcher\EventSubscriberInterface;use Symfony\Component\Security\Core\Exception\AccessDeniedException;

class MySubscriber implements EventSubscriberInterface
{
    /**
     * @var \LAG\AdminBundle\Admin\Configuration\ApplicationConfiguration
     */
    private $applicationConfiguration;
    
    public static function getSubscribedEvents()
    {
        return [
            Events::ADMIN_HANDLE_REQUEST => 'handleRequest',
        ];
    }

    public function __construct(ApplicationConfigurationStorage $applicationConfigurationStorage)
    {        
        $this->applicationConfiguration = $applicationConfigurationStorage->getConfiguration();
    }
    
    public function handleRequest(AdminEvent $event)
    {
        // Check if the security is enabled in the global Admin Application configuration
        if (!$this->applicationConfiguration->getParameter('enable_security')) {
            return;
        }
        $configuration = $event->getAdmin()->getConfiguration();
        $roles = $configuration->getParameter('permissions');
            
        // Do something to check if the user is allowed. If not, throw an AccessDeniedException        
        if (!$allowed) {
            throw new AccessDeniedException();
        }
    }
}

ADMIN_FILTER

The ADMIN_FILTER event is in charge of creating filters according to the configuration. Those filters will be applied to the query builder (when using Doctrine ORM). A form is built with the filters to be displayed.

Filters are only relevant in a list action. When only entity or no entity is loaded, the identifier will be used to load the entity.

Override the filter form

Filters can be configured using the Admin yaml configuration. See the Filters documentation for more information. Sometimes, you may want to override the whole filter form to use your custom form. This can be achieved using the ADMIN_FILTER event.

use LAG\AdminBundle\Event\EventsOLD;
use LAG\AdminBundle\Event\EventsOLD\FilterEvent;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;

class FilterSubscriber implements EventSubscriberInterface
{
    public static function getSubscribedEvents()
    {
        return [
            Events::ADMIN_FILTER => 'onFilter',
        ];
    }

    public function onFilter(FilterEvent $event): void
    {
        // Remove the existing filter form
        $event->removeForm('filter');
           
        // Add new custom filter form. The removeForm() method should be called before setting a new custom form
        $event->addForm($myCustomForm, 'filter');
    }
}

Add a custom Filter object

Usually the filter form is built from the configuration. When the yaml configuration is not sufficient, you can add your custom filter object or remove existing filters.

Filters object should implement LAG\AdminBundle\Filter\FilterInterface.

use LAG\AdminBundle\Event\EventsOLD;
use LAG\AdminBundle\Event\EventsOLD\FilterEvent;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;

class FilterSubscriber implements EventSubscriberInterface
{
    public static function getSubscribedEvents()
    {
        return [
            Events::ADMIN_FILTER => 'onFilter',
        ];
    }

    public function onFilter(FilterEvent $event): void
    {
        // Get existing filters
        $filters = $event->getFilters();
        
        // Add your custom filter
        $event->addFilter($myCustomFilter);

        // Or remove any existing filters
        $event->clearFilters();
    }
}

ENTITY_LOAD

This event is in charge of entity loading from the database. For the list action, several entities should be loaded. For the edit and create action, only one entity is loaded.

For more information about loading strategy, see the Loading Strategy documentation.

Load entities with a custom code

The AdminBundle load entities using data providers (see the Data Provider) documentation for more information about data providers. But you can load entities using your custom code.

use Doctrine\Common\Collections\ArrayCollection;
use LAG\AdminBundle\Event\EventsOLD;
use LAG\AdminBundle\Event\EventsOLD\EntityEvent;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;

class AdminSubscriber implements EventSubscriberInterface
{
    /**
     * @return array
     */
    public static function getSubscribedEvents()
    {
        return [
            // Use a priority higher than 255
            Events::ENTITY_LOAD => [
                'loadEntities', 300,
            ],            
        ];
    }
    
    public function loadEntities(EntityEvent $event): void
    {
        // Load your entities
        // ...
        
        // Set the event entities which will be passed to the Admin
        $event->setEntities(new ArrayCollection($myEntities));
    }
}

ADMIN_CREATE_FORM

Documentation in progress...

ADMIN_FILTER

Documentation in progress...

ADMIN_VIEW

Documentation in progress...

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