parseTemplate

The parseTemplate hook is triggered before parsing a template. It passes the template object and does not expect a return value. This hook is useful to transform existing template data or to enrich the template with additional variables or even functions.

Parameters

  1. \Contao\Template $template

    The front end or back end template instance.

Examples

The following example will provide an additional variable called foobar in any fe_page template:

// src/EventListener/ParseTemplateListener.php
namespace App\EventListener;

use Contao\CoreBundle\DependencyInjection\Attribute\AsHook;
use Contao\Template;

#[AsHook('parseTemplate')]
class ParseTemplateListener
{
    public function __invoke(Template $template): void
    {
        if ('fe_page' === $template->getName() || 0 === strpos($template->getName(), 'fe_page_')) {
            $template->foobar = 'foobar';
        }
    }
}

The following example provides an additional isMemberOf function in any front end template, which will check whether the currently logged in member is a member of the given group ID (or IDs):

// src/EventListener/ParseTemplateListener.php
namespace App\EventListener;

use Contao\CoreBundle\Security\ContaoCorePermissions;
use Contao\CoreBundle\DependencyInjection\Attribute\AsHook;
use Contao\FrontendTemplate;
use Contao\Template;
use Symfony\Component\Security\Core\Authorization\AuthorizationCheckerInterface;

#[AsHook('parseTemplate')]
class ParseTemplateListener
{
    public function __construct(
        private readonly AuthorizationCheckerInterface $authorizationChecker
    ) {
    }

    public function __invoke(Template $template): void
    {
        if (!$template instanceof FrontendTemplate) {
            return;
        }

        $template->isMemberOf = function ($groupId): bool {
            return $this->authorizationChecker->isGranted(ContaoCorePermissions::MEMBER_IN_GROUPS, $groupId);
        };
    }
}

<!-- templates/my_template.html5 -->
<?php if ($this->isMemberOf(1)): ?>
  <p>Member belongs to group ID 1!</p>
<?php endif; ?>

<?php if ($this->isMemberOf([1, 2])): ?>
  <p>Member belongs to group IDs 1 or 2!</p>
<?php endif; ?>

The ContaoCorePermissions::MEMBER_IN_GROUPS check is only available in Contao 4.12 or higher.

References