DateTime custom handler not working

[redayoub]

I'm trying to add a custom handler for DateTime but it's not working. I've tested with other classes and it works.

I'm using the same exact code from the doc.

<?php

namespace AppBundle\Service;

use JMS\Serializer\Handler\SubscribingHandlerInterface;
use JMS\Serializer\GraphNavigator;
use JMS\Serializer\JsonSerializationVisitor;
use JMS\Serializer\Context;

class MyHandler implements SubscribingHandlerInterface
{
    public static function getSubscribingMethods()
    {
        return array(
            array(
                'direction' => GraphNavigator::DIRECTION_SERIALIZATION,
                'format' => 'json',
                'type' => 'DateTime',
                'method' => 'serializeDateTimeToJson',
            ),
        );
    }

    public function serializeDateTimeToJson(JsonSerializationVisitor $visitor, \DateTime $date, array $type, Context $context)
    {
        return $date->format($type['params'][0]);
    }
}

my_handler:
  class: AppBundle\Service\MyHandler
  tags:
    - { name: jms_serializer.handler, type: DateTime, format: json } 

$date = new \DateTime;
$json = $this->get('jms_serializer')->serialize($date, 'json');

[goetas]

make sure the original date time handler is not enabled

[redayoub]

how can I do that, please?

[goetas]

register your my_handler with higher priority than the jms_serializer.datetime_handler service

[piotr-cz]

Try adding "priority" => -1 like so:

public static function getSubscribingMethods()
{
    return [
        [
            'direction' => GraphNavigator::DIRECTION_SERIALIZATION,
            'format' => 'json',
            'type' => 'DateTime',
            'method' => 'serializeDateTimeToJson',
            'priority' => -1,
        ],
    ];
}