Export::saveProgressParameters

protected function saveProgressParameters(): void
{
	// store state
	$progressData = [
		'processToken' => $this->processToken,
	];
	foreach ($this->fieldToStoreInProcess as $fieldName)
	{
		$progressData[$fieldName] = $this->{$fieldName};
	}

	$progressData = (new Signer())->sign(Json::encode($progressData));

	$localStorage = Application::getInstance()->getLocalSession($this->module.'_export_stepper');
	$localStorage->set($this->getProgressParameterOptionName(), $progressData);
}