Doctrine connection in Twig extension - Symfony - symfony

Question

According to what I've read online, it should be possible to create Doctrine connection inside Twig extensions file. I'd like to create an extension with filter that would recieve id of category and then return position of that category in the categery tree as it was established in database.
Twig extension file:
(Symfony/src/MyProject/AdminBundle/Twig/MyExtension.php)
<?php
namespace MyProject\AdminBundle\Twig;
class ToolboxExtension extends \Twig_Extension
{
protected $em;
public function __construct($em)
{
$this->em = $em;
}
public function getFilters()
{
return array(
new \Twig_SimpleFilter('path', array($this, 'categoryPath'))
);
}
public function categoryPath($category_id) {
$repository = $this->$em->getRepository('MyProjectAdminBundle:Category');
$category = $repository->findOneById($category_id);
$path = $repository->getPath($category);
return implode(">", $path);
return $category;
}
public function getName()
{
return 'toolbox_extension';
}
}
Services configuration file:
(Symfony/src/MyProject/AdminBundle/Resources/config/services.yml)
services:
myproject.twig.toolbox_extension:
class: MyProject\AdminBundle\Twig\MyExtension
tags:
- { name: twig.extension }
arguments:
em: "#doctrine.orm.entity_manager"
But whenever I use this filter categoryPath, Twig crashes. So the template is loaded only until the first usage of this extension.

Answer 1

For me, solution below work perfect. I found post on google groups which resolve my problem with doctrine in Twig extensions.
In my AppBundle\Resources\services.yml:
app.twig.get_province.extension:
class: AppBundle\Twig\GetProvinceExtension
tags:
- { name: twig.extension }
arguments: [ '#doctrine.orm.entity_manager' ]
In AppBundle\Twig\GetProvinceExtention.php:
class GetProvinceExtension extends \Twig_Extension {
/**
* #var EntityManager
*/
protected $em;
/**
* GetProvinceExtension constructor.
* #param EntityManager $em
*/
public function __construct(EntityManager $em) {
$this->em = $em;
}
public function getFilters() {
return [
new \Twig_SimpleFilter('province', [$this, 'provinceFilter']),
];
}
public function provinceFilter($code) {
$province = $this->em->getRepository("AppBundle:Province")
->findOneBy([ "code" => $code ]);
return $province->getName();
}
}

Answer 2

Try replacing $this->em-> with $this->$em->.

Answer 3

Try replacing
$this->em->
with $this->$em->
and replacing
$this->em = $em;
with
$this->em = $em['em'];
and
arguments:
em: "#doctrine.orm.entity_manager"
with
arguments: [em: "#doctrine.orm.entity_manager"]

Answer 4

You can use
{% set Products = repository('Entity\\Products').findAll() %}
inside your twig
Then you can do a foreach by using
{% Product in Products %}
<p>{{ Product.name }}</p>
{% endfor %}