private function unserializeProductPositions(\Magento\Catalog\Model\Category $category)
{
$productPositions = $category->getSortedProducts() ? $category->getSortedProducts() : [];
if (is_string($productPositions)) {
try {
$productPositions = $this->jsonHelper->jsonDecode($productPositions);
} catch (\Exception $e) {
$productPositions = [];
}
}
$category->setSortedProducts($productPositions);
return $this;
}