检查WooCommerce优惠券是否已存在

Question

我正在编辑一个装箱单，这是在订单付款和打包时生成的。如果包含特定类别的产品，装箱单会自动添加优惠券，并在其上打印。

我的问题是，每次刷新或重新打开装箱单时，都会使用相同的优惠券代码生成新的优惠券。所以我想实现一个规则，检查coupon_code是否已经存在。

add_action( 'wpo_wcpdf_after_order_details', 'wpo_wcpdf_custom_text_categories', 10, 2 );
function wpo_wcpdf_custom_text_categories ($template_type, $order) {
    // collect categories from order items
    $order_cats = array();
    $items = $order->get_items();
    foreach ($items as $item_id => $item) {
        $product = $order->get_product_from_item($item);
        if ($product) {
            $terms = get_the_terms( $product->id , 'product_cat' );
            foreach ($terms as $term) {
                $order_cats[$term->term_id] = $term->name;
            }
        }
    }
    $target = array('Testtragen', 'Testtragetuch');
    // 
    // check for your category requirement
    if(count(array_intersect($order_cats, $target)) > 0 && $template_type == 'packing-slip'){
        $coupon_code = $order->get_order_number();
        $discount_type = 'fixed_product'; // Type: fixed_cart, percent, fixed_product, percent_product       
        $order_date = get_post_meta( $order->id, '_wcpdf_order_date', true );
        $due_date = date_i18n( get_option( 'date_format' ), strtotime( $invoice_date . ' + 60 days') );
        $email = $order->billing_email;   



        $amount = '10'; // Amount
        $discount_type = 'fixed_cart'; // Type: fixed_cart, percent, fixed_product, percent_product

        $coupon = array(
            'post_title'   => $coupon_code,
            'post_content' => '',
            'post_status'  => 'publish',
            'post_author'  => 1,
            'post_type'    => 'shop_coupon'
        );
        /*          
        $new_coupon_id = wp_insert_post( $coupon );

        // Add meta
        update_post_meta( $new_coupon_id, 'discount_type', $discount_type );
        update_post_meta( $new_coupon_id, 'coupon_amount', $amount );
        update_post_meta( $new_coupon_id, 'individual_use', 'no' );
        update_post_meta( $new_coupon_id, 'product_ids', '' );
        update_post_meta( $new_coupon_id, 'exclude_product_ids', '' );
        update_post_meta( $new_coupon_id, 'usage_limit', '' );
        update_post_meta( $new_coupon_id, 'expiry_date', '' );
        update_post_meta( $new_coupon_id, 'apply_before_tax', 'yes' );
        update_post_meta( $new_coupon_id, 'free_shipping', 'no' );   
        */
    }
}

所以我想在if之前添加一个wp_insert_post($coupon)语句，只有当coupon_code的优惠券不存在时才会执行所有这些代码。

我试过：term_exists( $coupon_code, ‘coupons’)but这没用。

谢谢你的帮助！

Answer 1

更新（添加了WooCommerce 3兼容性）

这是一个解决方案，为meta_key创建一个特殊的$order->id，以避免在刷新或重新打开装箱单时使用相同的优惠券代码生成新的优惠券。

这是您更改的代码（带注释说明）：

add_action( 'wpo_wcpdf_after_order_details', 'wpo_wcpdf_custom_text_categories', 10, 2 );
function wpo_wcpdf_custom_text_categories ($template_type, $order) {
    // collect categories from order items
    $order_cats = array();

    $order_id = method_exists( $order, 'get_id' ) ? $order->get_id() : $order->id;

    // Loop through order items
    foreach ($order->get_items() as $item_id => $item) {
        $product = version_compare( WC_VERSION, '3.0', '<' ) ? $product_id = version_compare( WC_VERSION, '3.0', '<' ) ? $cart_item['data']->id : $cart_item['data']->get_id() : $item->get_product();
        $product_id = method_exists( $product, 'get_id' ) ? $item->get_product_id() : $item['product_id'];
        if ($product) {
            $terms = get_the_terms( $product_id , 'product_cat' );
            foreach ($terms as $term) {
                $order_cats[$term->term_id] = $term->name;
            }
        }
    }
    $target = array('Testtragen', 'Testtragetuch');
    // 
    // check for your category requirement
    if(count(array_intersect($order_cats, $target)) > 0 && $template_type == 'packing-slip'){
        $coupon_code = $order->get_order_number();
        $discount_type = 'fixed_product'; // Type: fixed_cart, percent, fixed_product, percent_product       
        $order_date = get_post_meta( $order_id, '_wcpdf_order_date', true );
        $due_date = date_i18n( get_option( 'date_format' ), strtotime( $invoice_date . ' + 60 days') );
        $email = method_exists( $order, 'get_billing_email' ) ? $order->get_billing_email() : $order->billing_email;

        $amount = '10'; // Amount
        $discount_type = 'fixed_cart'; // Type: fixed_cart, percent, fixed_product, percent_product

        $coupon = array(
            'post_title'   => $coupon_code,
            'post_content' => '',
            'post_status'  => 'publish',
            'post_author'  => 1,
            'post_type'    => 'shop_coupon'
        );


        // @@@ We create a meta_key '_wcpdf_coupon' for this order with value 'no'
        if( empty( get_post_meta( $order_id, '_wcpdf_coupon', true) ) ) {
            add_post_meta( $order_id, '_wcpdf_coupon', 'no', true );
        }

        // @@@ if this meta_key for this order has a value = 'no' was update it to 'yes'
        if( get_post_meta( $order_id, '_wcpdf_coupon', true) == 'no' ) {

            // Now we update it to 'yes'. This avoid the coupon be reused for this order.
            update_post_meta( $order_id, '_wcpdf_coupon', 'yes');

            $new_coupon_id = wp_insert_post( $coupon );

            // Add meta
            update_post_meta( $new_coupon_id, 'discount_type', $discount_type );
            update_post_meta( $new_coupon_id, 'coupon_amount', $amount );
            update_post_meta( $new_coupon_id, 'individual_use', 'no' );
            update_post_meta( $new_coupon_id, 'product_ids', '' );
            update_post_meta( $new_coupon_id, 'exclude_product_ids', '' );
            update_post_meta( $new_coupon_id, 'usage_limit', '' );
            update_post_meta( $new_coupon_id, 'expiry_date', '' );
            update_post_meta( $new_coupon_id, 'apply_before_tax', 'yes' );
            update_post_meta( $new_coupon_id, 'free_shipping', 'no' );
        }
    }
}

这应该解决这个问题......