Sync.php

См. документацию.

<?php
 
namespace Bitrix\Im\V2\Controller;
 
use Bitrix\Im\V2\Error;
use Bitrix\Im\V2\Sync\SyncService;
use Bitrix\Main\ObjectException;
use Bitrix\Main\Type\DateTime;
use DateTimeInterface;
 
class Sync extends BaseController
{
    private const DATE_FORMAT = DateTimeInterface::RFC3339;
 
    public function listAction(array $filter = [], int $limit = 50): ?array
    {
        $syncService = new SyncService();
 
        if (isset($filter['lastDate']))
        {
            try
            {
                $date = new DateTime($filter['lastDate'], self::DATE_FORMAT);
            }
            catch (ObjectException $exception)
            {
                $this->addError(new Error($exception->getCode(), $exception->getMessage()));
 
                return null;
            }
        }
        else
        {
            $date = new DateTime(null, self::DATE_FORMAT);
        }
 
        return $syncService->getChangesFromDate($date, $limit);
    }
}