Symfony + FOS Rest + JMS serializer - Serialization handler

README.md

Symfony + FOS Rest + JMS serializer - Serialization handler

During building an API service, I encountered with a problem, that I did not want to serve everything as Doctrine Entity object and also, not everything can be converted to json (E.g. Darsyn\IP\Version\Multi)

This issues can be solved by converting one format (used in Doctrine Entity) to wanted format (used in REST API response) We can achieve this via JMS Handlers

To use it you can simply create a Symfony controller

class SalesOrderController extends FOSRestController
{
    public function listAction(): Response
    {
        $allEntities = $this->myRepository->findAll();
        // Let's say one entity is holding info about creation date in \DateTime format, but we want to show it as timestamp.
        $view = $this->view($allEntities, Response::HTTP_OK);

        return $this->handleView($view);
    }
}

And then create and register JMS handler (code below)

DateTimeHandler.php

<?php

declare(strict_types=1);

namespace MyApp\Infrastructure\Handler;

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

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

    /**
     * @param JsonSerializationVisitor $visitor
     * @param \DateTime $ipAddress
     * @param array $type
     * @param Context $context
     *
     * @return string
     *
     * @throws \Darsyn\IP\Exception\IpException
     * @throws \Darsyn\IP\Exception\WrongVersionException
     */
    public function serializeIpAddressToJson(JsonSerializationVisitor $visitor, \DateTime $dateTime, array $type, Context $context)
    {
        return $dateTime->getTimestamp;
    }
}

services.yaml

services:

  # Json Serialize handler
   MyApp\Infrastructure\Handler\DateTimeHandler:
    class: 'MyApp\Infrastructure\Handler\DateTimeHandler'
    tags:
      - { name: jms_serializer.subscribing_handler }