基于三级自定义分类及RankMath主术语优化WooCommerce关联商品

问题说明 #

我有一个带自定义分类sport的WooCommerce商店，该分类分三级：父级>子级>孙级（比如Indoor Sport > Arena Sport > Basketball）。浏览篮球商品时，希望关联商品优先展示同孙级（Basketball）的商品，数量不足时再降级显示子级（Arena Sport）的商品，以此类推。

同时我用RankMath插件设置了「主术语」（Primary），通常是孙级，偶尔也会是子级。当前代码仅能匹配子级分类商品，无法优先展示主术语对应的孙级商品，需要修改代码实现按优先级匹配的逻辑。

现有代码 #

add_filter( 'woocommerce_related_products', 'related_products_from_rankmath_primary_esporte_taxonomy', 10, 3 );
function related_products_from_rankmath_primary_esporte_taxonomy( $related_posts, $product_id, $args ) {
    $taxonomy     = 'sport'; 
    $term_ids     = wp_get_post_terms( $product_id, $taxonomy, array( 'fields' => 'ids' ) ); 
    $term_slugs   = array(); 

 if( count($term_ids) == 1 ) {
        // Get children categories
        $children_ids = get_term_children( reset($category_ids), $taxonomy );
        // Loop through children terms Ids
        foreach ( $children_ids as $tem_id ) {
            $term_slugs[] = get_term_by( 'id', $tem_id, $taxonomy )->slug; // get the slug from each term Id
        }
    } 
    elseif( count( $term_ids ) > 1 ) {
        // Get the primary taxonomy/term as saved by Rank Math SEO
        $primary_tax_id = get_post_meta( $product_id, 'rank_math_primary_taxonomy', true );
        $term_slugs[]   = get_term_by( 'id', $primary_tax_id, $taxonomy )->slug; // get the slug from the term Id
    }
        
        
    if ( count( $term_ids ) > 0 ) {
        foreach ( $term_ids as $term_id ) {
            $term_slugs[] = get_term_by( 'id', $term_id, $taxonomy )->slug; 

            // Gets the IDs of child terms
            $children_ids = get_term_children( $term_id, $taxonomy );

            foreach ( $children_ids as $child_id ) {
                $term_slugs[] = get_term_by( 'id', $child_id, $taxonomy )->slug; // Gets the slug of each child term
            }
        }

        $related_posts = wc_get_products( array(
            'status'        => 'publish',
            'tax_query'     => array(
                array(
                    'taxonomy' => $taxonomy,
                    'field'    => 'slug',
                    'terms'    => $term_slugs,
                ),
            ),
            'return'        => 'ids',
            'exclude'       => array( $product_id ),
            'visibility'    => 'catalog',
            'limit'         => -1,
        ) );
    }

    return $related_posts;
}

修改方案 #

核心逻辑是按优先级顺序查询商品：先收集主术语下的商品，数量不够则向上取父级术语的商品补充，直到达到默认的关联商品数量。具体修改如下：

修改后的代码 #

add_filter( 'woocommerce_related_products', 'related_products_from_rankmath_primary_sport_taxonomy', 10, 3 );
function related_products_from_rankmath_primary_sport_taxonomy( $related_posts, $product_id, $args ) {
    $taxonomy = 'sport';
    $default_limit = $args['posts_per_page']; // 获取默认关联商品数量
    $related_ids = array();

    // 1. 获取主术语ID（优先RankMath设置的主术语）
    $primary_tax_id = get_post_meta( $product_id, 'rank_math_primary_taxonomy', true );
    if ( empty( $primary_tax_id ) ) {
        $term_ids = wp_get_post_terms( $product_id, $taxonomy, array( 'fields' => 'ids' ) );
        $primary_tax_id = reset( $term_ids ); // 没有主术语则取第一个分类ID
    }

    if ( empty( $primary_tax_id ) ) {
        return $related_posts; // 无分类则返回原关联商品
    }

    // 2. 构建优先级术语链：主术语 → 父级术语 → 顶级父级
    $term_chain = array();
    $current_term = get_term( $primary_tax_id, $taxonomy );
    
    while ( ! is_wp_error( $current_term ) && $current_term ) {
        $term_chain[] = $current_term->slug;
        $current_term = get_term( $current_term->parent, $taxonomy ); // 向上遍历父级
    }

    // 3. 按优先级查询商品，先取主术语的，数量不够再补父级的
    foreach ( $term_chain as $term_slug ) {
        if ( count( $related_ids ) >= $default_limit ) {
            break; // 数量够了就停止
        }

        $remaining = $default_limit - count( $related_ids );
        $products = wc_get_products( array(
            'status'        => 'publish',
            'tax_query'     => array(
                array(
                    'taxonomy' => $taxonomy,
                    'field'    => 'slug',
                    'terms'    => $term_slug,
                    'operator' => 'IN'
                ),
            ),
            'return'        => 'ids',
            'exclude'       => array_merge( array( $product_id ), $related_ids ), // 排除当前商品和已选商品
            'visibility'    => 'catalog',
            'limit'         => $remaining,
        ) );

        $related_ids = array_merge( $related_ids, $products );
    }

    // 4. 返回最终的关联商品ID数组
    return $related_ids;
}

关键修改点说明 #

• 优先级术语链：从主术语开始向上遍历所有父级，形成明确的优先级顺序（孙级→子级→父级）
• 分步查询：按术语优先级依次查询商品，每次只补够剩余需要的数量，保证高优先级商品先展示
• 排除已选商品：每次查询时排除已经选中的商品，避免重复
• 适配默认数量：使用WooCommerce默认的关联商品数量$args['posts_per_page']，无需硬编码

内容的提问来源于stack exchange，提问作者quizzical