产品架构不再适用于Rich Snippets

如何解决产品架构不再适用于Rich Snippets

我一直在我的functions.php中使用以下代码来为Woocommerce中的产品提供架构标记。在最新的PHP更新之前，它已在Rich Snippets中完美运行。现在，它只返回解析错误：缺少'，'或'}'

经过大量测试，似乎我的代码的描述部分导致了问题。关于为什么突然停止工作以及我应该使用什么的任何想法？

谢谢。

function product_schema(){
global $product;
if (! is_product()){
return;
}
?>
<title><?php echo the_title();?></title>
<script type="application/ld+json">
{
"@context": "https://schema.org/","@type": "Product","name": "<?php echo the_title(); ?>","image": "<?php echo get_the_post_thumbnail_url(); ?>","description": "<?php echo $product->get_short_description(); ?>","sku": "<?php echo $product->get_sku(); ?>","mpn": "<?php echo get_the_id(); ?>","brand": {
"@type": "Brand","name": "<?php echo get_bloginfo('name'); ?>"
},"review": {
"@type": "Review","reviewRating": {
"@type": "Rating","ratingValue": "5","bestRating": "5"
},"author": {
"@type": "Person","name": "<?php the_author(); ?>"
}
},"aggregateRating": {
"@type": "AggregateRating","ratingValue": "4.9","reviewCount": "89"
},"offers": {
"@type": "Offer","url": "<?php echo get_permalink(); ?>","priceCurrency": "<?php echo get_woocommerce_currency(); ?>","price": "<?php echo $product->get_price(); ?>","priceValidUntil": "<?php echo get_the_date(); ?>","itemCondition": "https://schema.org/NewCondition","availability": "<?php echo $product->get_stock_status(); ?>"
}
}
</script>
<?
}
add_action ('wp_footer','product_schema');