How to have a global variable coming from db in symfony template? - symfony

Question

How can I have a global variable in symfony template?
I did read this
but I prefer to fetch parameter from database, I think this service will be loaded on startup before it can fetch anything from db. Is it possible to do a trick to do so?

Answer 1

EDIT: Update in 2019 with Symfony 3.4+ syntax.
Create a Twig extension where you inject the Entity Manager:
Fuz/AppBundle/Twig/Extension/DatabaseGlobalsExtension.php
<?php
namespace Fuz\AppBundle\Twig\Extension;
use Doctrine\ORM\EntityManager;
use Twig\Extension\AbstractExtension;
use Twig\Extension\GlobalsInterface;
class DatabaseGlobalsExtension extends AbstractExtension implements GlobalsInterface
{
protected $em;
public function __construct(EntityManager $em)
{
$this->em = $em;
}
public function getGlobals()
{
return [
'myVariable' => $this->em->getRepository(FuzAppBundle\Entity::class)->getSomeData(),
];
}
}
Register your extension in your Fuz/AppBundle/Resources/config/services.yml:
services:
_defaults:
autowire: true
autoconfigure: true
Fuz\AppBundle\Twig\Extension\DatabaseGlobalsExtension: ~
Now you can do the requests you want using the entity manager.
Don't forget to replace paths and namespaces to match with your application.

Answer 2

As of this day, the class signature has changed. You must implement \ Twig_Extension_GlobalsInterface, without it, your globals won't show up.
class MyTwigExtension extends \Twig_Extension implements Twig_Extension_GlobalsInterface
{ }
Bye!

Answer 3

you can register a twig extension
services:
twig_extension:
class: Acme\DemoBundle\Extension\TwigExtension
arguments: [#doctrine]
tags:
- { name: twig.extension }
And then in the TwigExtension you can do as follows:
class TwigExtension extends \Twig_Extension
{
public function getGlobals() {
return array(
// your key => values to make global
);
}
}
So you could get a value from the database in this TwigExtension and pass it to the template with the getGlobals() function

Answer 4

Stay away from global variables.
Instead make a custom twig extension then inject the database connection as a parameter.
Something like:
services:
acme.twig.acme_extension:
class: Acme\DemoBundle\Twig\AcmeExtension
arguments: [#doctrine.dbal.default_connection]
tags:
- { name: twig.extension }
Details:
http://symfony.com/doc/current/cookbook/templating/twig_extension.html