Add YAML type in Doctrine (with Symfony)

AppBundle.php

namespace AppBundle;

use Doctrine\DBAL\Types\Type;
use Symfony\Component\HttpKernel\Bundle\Bundle;

class AppBundle extends Bundle
{
    public function boot() {
        Type::addType('yaml', 'AppBundle\Extension\YamlType');
        $em = $this->container->get('doctrine.orm.default_entity_manager');
        $em->getConnection()->getDatabasePlatform()->registerDoctrineTypeMapping('YAML', 'yaml');
    }
}

YamlType.php

<?php
namespace AppBundle\Extension;


use Doctrine\DBAL\Platforms\AbstractPlatform;
use Doctrine\DBAL\Types\Type;
use Symfony\Component\Yaml\Parser;
use Symfony\Component\Yaml\Yaml;

/**
 * Type that maps a PHP array to a clob SQL type using the YML representation.
 *
 * @author Remy Mellet <remy.mellet@gmail.com>
 */
class YamlType extends Type
{

    /**
     * {@inheritdoc}
     */
    public function getSQLDeclaration(array $fieldDeclaration, AbstractPlatform $platform)
    {
        return $platform->getClobTypeDeclarationSQL($fieldDeclaration);
    }

    /**
     * {@inheritdoc}
     */
    public function convertToDatabaseValue($value, AbstractPlatform $platform)
    {
        if (null === $value) {
            return null;
        }
        return Yaml::dump($value); //object to yml as string
    }

    /**
     * {@inheritdoc}
     */
    public function convertToPHPValue($value, AbstractPlatform $platform)
    {
        if ($value === null || $value === '') {
            return array();
        }
        return Yaml::parse($value); //yml as string to object
    }

    /**
     * {@inheritdoc}
     */
    public function getName()
    {
        return "yaml"; //Type::YAML;
    }

    /**
     * {@inheritdoc}
     */
    public function requiresSQLCommentHint(AbstractPlatform $platform)
    {
        return true;
    }
}