WordPress从入门到精通(第二部分)

<?php
/**
 * Plugin Name:       My Custom Plugin
 * Plugin URI:        https://example.com/my-plugin
 * Description:       A custom WordPress plugin for demonstration.
 * Version:           1.0.0
 * Requires at least: 6.0
 * Requires PHP:      7.4
 * Author:            Your Name
 * Author URI:        https://example.com
 * License:           GPL v2 or later
 * License URI:       https://www.gnu.org/licenses/gpl-2.0.html
 * Text Domain:       my-plugin
 * Domain Path:       /languages
 */

// 防止直接访问
if (!defined('ABSPATH')) {
    exit;
}

// 常量定义
define('MY_PLUGIN_VERSION', '1.0.0');
define('MY_PLUGIN_DIR', plugin_dir_path(__FILE__));
define('MY_PLUGIN_URL', plugin_dir_url(__FILE__));

// 激活钩子
register_activation_hook(__FILE__, 'my_plugin_activate');
function my_plugin_activate() {
    // 创建数据库表
    global $wpdb;
    $table_name = $wpdb->prefix . 'my_plugin_data';
    $charset_collate = $wpdb->get_charset_collate();

    $sql = "CREATE TABLE $table_name (
        id mediumint(9) NOT NULL AUTO_INCREMENT,
        name varchar(100) NOT NULL,
        value text,
        created_at datetime DEFAULT CURRENT_TIMESTAMP,
        PRIMARY KEY (id)
    ) $charset_collate;";

    require_once(ABSPATH . 'wp-admin/includes/upgrade.php');
    dbDelta($sql);

    // 设置默认选项
    add_option('my_plugin_settings', array(
        'enabled'      => true,
        'title'        => 'My Plugin',
        'items_per_page' => 10,
    ));

    // 设置默认选项
    flush_rewrite_rules();
}

// 停用钩子
register_deactivation_hook(__FILE__, 'my_plugin_deactivate');
function my_plugin_deactivate() {
    flush_rewrite_rules();
}

// 加载国际化
function my_plugin_load_textdomain() {
    load_plugin_textdomain('my-plugin', false, dirname(plugin_basename(__FILE__)) . '/languages');
}
add_action('init', 'my_plugin_load_textdomain');

// 加载后台脚本
function my_plugin_admin_scripts($hook) {
    if (strpos($hook, 'my-plugin') === false) {
        return;
    }

    wp_enqueue_style('my-plugin-admin', MY_PLUGIN_URL . 'admin/css/admin.css', array(), MY_PLUGIN_VERSION);
    wp_enqueue_script('my-plugin-admin', MY_PLUGIN_URL . 'admin/js/admin.js', array('jquery'), MY_PLUGIN_VERSION, true);

    wp_localize_script('my-plugin-admin', 'myPluginAdmin', array(
        'ajaxUrl' => admin_url('admin-ajax.php'),
        'nonce'   => wp_create_nonce('my_plugin_nonce'),
    ));
}
add_action('admin_enqueue_scripts', 'my_plugin_admin_scripts');

// 加载前台脚本
function my_plugin_frontend_scripts() {
    wp_enqueue_style('my-plugin-frontend', MY_PLUGIN_URL . 'public/css/frontend.css', array(), MY_PLUGIN_VERSION);
    wp_enqueue_script('my-plugin-frontend', MY_PLUGIN_URL . 'public/js/frontend.js', array(), MY_PLUGIN_VERSION, true);
}
add_action('wp_enqueue_scripts', 'my_plugin_frontend_scripts');

<?php
// 添加顶级菜单
function my_plugin_menu() {
    add_menu_page(
        'My Plugin',                 // 页面标题
        'My Plugin',                 // 菜单标题
        'manage_options',            // 权限
        'my-plugin',                 // Slug
        'my_plugin_settings_page',   // 回调函数
        'dashicons-admin-plugins',   // 图标
        80                           // 位置
    );

    // 添加子菜单
    add_submenu_page(
        'my-plugin',
        'Settings',
        'Settings',
        'manage_options',
        'my-plugin-settings',
        'my_plugin_settings_page'
    );

    add_submenu_page(
        'my-plugin',
        'Data',
        'Data',
        'manage_options',
        'my-plugin-data',
        'my_plugin_data_page'
    );

    // 隐藏重复的子菜单（第一个子菜单 = 顶级菜单）
    global $submenu;
    unset($submenu['my-plugin'][0]);
}
add_action('admin_menu', 'my_plugin_menu');

// 设置页面内容
function my_plugin_settings_page() {
    ?>
    <div class="wrap">
        <h1>My Plugin Settings</h1>
        <form method="post" action="options.php">
            <?php
            settings_fields('my_plugin_settings_group');
            do_settings_sections('my-plugin-settings');
            submit_button();
            ?>
        </form>
    </div>
    <?php
}

// 注册设置
function my_plugin_register_settings() {
    register_setting('my_plugin_settings_group', 'my_plugin_settings', array(
        'sanitize_callback' => 'my_plugin_sanitize_settings',
    ));

    add_settings_section(
        'my_plugin_general_section',
        'General Settings',
        'my_plugin_section_callback',
        'my-plugin-settings'
    );

    add_settings_field(
        'my_plugin_enabled',
        'Enable Plugin',
        'my_plugin_enabled_callback',
        'my-plugin-settings',
        'my_plugin_general_section'
    );

    add_settings_field(
        'my_plugin_title',
        'Plugin Title',
        'my_plugin_title_callback',
        'my-plugin-settings',
        'my_plugin_general_section'
    );
}
add_action('admin_init', 'my_plugin_register_settings');

// 字段回调
function my_plugin_enabled_callback() {
    $options = get_option('my_plugin_settings');
    ?>
    <input type="checkbox" name="my_plugin_settings[enabled]" value="1" <?php checked(1, $options['enabled'] ?? 0); ?>>
    <?php
}

function my_plugin_title_callback() {
    $options = get_option('my_plugin_settings');
    ?>
    <input type="text" name="my_plugin_settings[title]" value="<?php echo esc_attr($options['title'] ?? ''); ?>" class="regular-text">
    <?php
}

// 清理回调
function my_plugin_sanitize_settings($input) {
    $sanitized = array();
    $sanitized['enabled'] = !empty($input['enabled']) ? 1 : 0;
    $sanitized['title'] = sanitize_text_field($input['title'] ?? '');
    return $sanitized;
}

<?php
// AJAX 处理（登录用户）
function my_plugin_ajax_handler() {
    // 验证 nonce
    if (!wp_verify_nonce($_POST['nonce'] ?? '', 'my_plugin_nonce')) {
        wp_send_json_error('Security check failed');
    }

    // 验证权限
    if (!current_user_can('manage_options')) {
        wp_send_json_error('Permission denied');
    }

    $action_type = sanitize_text_field($_POST['action_type'] ?? '');

    switch ($action_type) {
        case 'save_data':
            $name = sanitize_text_field($_POST['name'] ?? '');
            $value = sanitize_textarea_field($_POST['value'] ?? '');

            global $wpdb;
            $result = $wpdb->insert($wpdb->prefix . 'my_plugin_data', array(
                'name'  => $name,
                'value' => $value,
            ));

            if ($result) {
                wp_send_json_success(array('message' => 'Data saved successfully'));
            } else {
                wp_send_json_error('Failed to save data');
            }
            break;

        case 'get_data':
            global $wpdb;
            $data = $wpdb->get_results("SELECT * FROM {$wpdb->prefix}my_plugin_data ORDER BY created_at DESC LIMIT 10");
            wp_send_json_success($data);
            break;

        default:
            wp_send_json_error('Unknown action');
    }
}
add_action('wp_ajax_my_plugin_action', 'my_plugin_ajax_handler');

// AJAX 处理（未登录用户）
// add_action('wp_ajax_nopriv_my_plugin_action', 'my_plugin_ajax_handler');

// 添加动作
add_action('hook_name', 'callback_function', $priority, $accepted_args);

// 示例：在页面底部添加内容
function my_custom_footer_content() {
    echo '<p>Powered by My Theme</p>';
}
add_action('wp_footer', 'my_custom_footer_content');

// 常用 Action 钩子
// init                  WordPress 初始化后（加载主题/插件后）
// wp_loaded             所有内容加载完成后
// template_redirect     模板加载前
// wp_head               <head> 标签内
// wp_footer             </body> 标签前
// wp_body_open          <body> 标签打开后
// after_setup_theme     主题设置后
// wp_enqueue_scripts    前台脚本加载
// admin_enqueue_scripts 后台脚本加载
// save_post             保存文章后
// publish_post          发布文章后
// delete_post           删除文章后
// user_register         用户注册后
// wp_login              用户登录后
// wp_logout             用户登出后
// comment_post          发表评论后
// switch_theme          切换主题后
// admin_menu            添加后台菜单
// widgets_init          注册小工具

// 添加过滤器
add_filter('hook_name', 'callback_function', $priority, $accepted_args);

// 示例：修改文章标题
function my_custom_title($title) {
    if (is_single()) {
        $title = $title . ' - My Blog';
    }
    return $title;
}
add_filter('the_title', 'my_custom_title');

// 示例：修改摘要长度
function my_excerpt_length($length) {
    return 50;
}
add_filter('excerpt_length', 'my_excerpt_length', 999);

// 常用 Filter 钩子
// the_title             文章标题
// the_content           文章内容
// the_excerpt           文章摘要
// excerpt_length        摘要长度
// excerpt_more          摘要后缀
// wp_title              页面标题
// body_class            body 类名
// post_class            文章类名
// upload_mimes          允许上传的文件类型
// login_redirect        登录后跳转
// wp_mail_from          邮件发送者
// wp_mail_from_name     邮件发送者名称
// comment_text          评论内容
// wp_nav_menu_items     菜单项 HTML
// widget_display_callback 小工具显示
// the_editor            编辑器内容
// query_vars            查询变量
// cron_schedules        自定义 cron 间隔

// 自定义 Action
do_action('my_custom_action', $arg1, $arg2);

// 其他代码中使用
add_action('my_custom_action', 'my_callback_function', 10, 2);
function my_callback_function($arg1, $arg2) {
    // 处理逻辑
}

// 自定义 Filter
$value = apply_filters('my_custom_filter', $original_value, $arg1);

// 其他代码中使用
add_filter('my_custom_filter', 'my_filter_function', 10, 2);
function my_filter_function($value, $arg1) {
    return $value . ' modified';
}

<?php
// 注册自定义端点
function my_plugin_register_rest_routes() {
    register_rest_route('my-plugin/v1', '/data', array(
        'methods'             => 'GET',
        'callback'            => 'my_plugin_get_data',
        'permission_callback' => 'my_plugin_check_permission',
        'args'                => array(
            'per_page' => array(
                'default'           => 10,
                'sanitize_callback' => 'absint',
            ),
            'page' => array(
                'default'           => 1,
                'sanitize_callback' => 'absint',
            ),
        ),
    ));

    register_rest_route('my-plugin/v1', '/data', array(
        'methods'             => 'POST',
        'callback'            => 'my_plugin_create_data',
        'permission_callback' => 'my_plugin_check_permission',
    ));

    register_rest_route('my-plugin/v1', '/data/(?P<id>\d+)', array(
        'methods'             => 'PUT',
        'callback'            => 'my_plugin_update_data',
        'permission_callback' => 'my_plugin_check_permission',
    ));

    register_rest_route('my-plugin/v1', '/data/(?P<id>\d+)', array(
        'methods'             => 'DELETE',
        'callback'            => 'my_plugin_delete_data',
        'permission_callback' => 'my_plugin_check_permission',
    ));
}
add_action('rest_api_init', 'my_plugin_register_rest_routes');

// 权限检查
function my_plugin_check_permission($request) {
    return current_user_can('edit_posts');
}

// GET - 获取数据
function my_plugin_get_data($request) {
    global $wpdb;
    $per_page = $request->get_param('per_page');
    $page = $request->get_param('page');
    $offset = ($page - 1) * $per_page;

    $data = $wpdb->get_results($wpdb->prepare(
        "SELECT * FROM {$wpdb->prefix}my_plugin_data LIMIT %d OFFSET %d",
        $per_page, $offset
    ));

    $total = $wpdb->get_var("SELECT COUNT(*) FROM {$wpdb->prefix}my_plugin_data");

    return new WP_REST_Response(array(
        'data'       => $data,
        'total'      => (int) $total,
        'page'       => (int) $page,
        'per_page'   => (int) $per_page,
        'total_pages' => ceil($total / $per_page),
    ), 200);
}

// POST - 创建数据
function my_plugin_create_data($request) {
    global $wpdb;

    $name = sanitize_text_field($request->get_param('name'));
    $value = sanitize_textarea_field($request->get_param('value'));

    $result = $wpdb->insert($wpdb->prefix . 'my_plugin_data', array(
        'name'  => $name,
        'value' => $value,
    ));

    if ($result) {
        return new WP_REST_Response(array(
            'id'      => $wpdb->insert_id,
            'message' => 'Created successfully',
        ), 201);
    }

    return new WP_REST_Response(array('message' => 'Failed to create'), 500);
}

// PUT - 更新数据
function my_plugin_update_data($request) {
    global $wpdb;
    $id = $request->get_param('id');

    $result = $wpdb->update(
        $wpdb->prefix . 'my_plugin_data',
        array(
            'name'  => sanitize_text_field($request->get_param('name')),
            'value' => sanitize_textarea_field($request->get_param('value')),
        ),
        array('id' => $id)
    );

    return new WP_REST_Response(array('message' => 'Updated successfully'), 200);
}

// DELETE - 删除数据
function my_plugin_delete_data($request) {
    global $wpdb;
    $id = $request->get_param('id');

    $result = $wpdb->delete($wpdb->prefix . 'my_plugin_data', array('id' => $id));

    return new WP_REST_Response(array('message' => 'Deleted successfully'), 200);
}

<?php
// 修改文章 API 返回的字段
function my_plugin_modify_post_response($response, $post) {
    $data = $response->get_data();
    $data['custom_field'] = get_post_meta($post->ID, 'custom_field', true);
    $data['reading_time'] = ceil(str_word_count(strip_tags($post->post_content)) / 200) . ' min';
    $response->set_data($data);
    return $response;
}
add_filter('rest_prepare_post', 'my_plugin_modify_post_response', 10, 2);

// 注册自定义文章字段
function my_plugin_register_post_meta() {
    register_post_meta('post', 'custom_field', array(
        'show_in_rest'  => true,
        'single'        => true,
        'type'          => 'string',
        'auth_callback' => function() {
            return current_user_can('edit_posts');
        },
    ));
}
add_action('init', 'my_plugin_register_post_meta');

// functions.php 中添加优化代码

// 1. 禁用 Emoji 脚本（不需要时）
function disable_emoji() {
    remove_action('wp_head', 'print_emoji_detection_script', 7);
    remove_action('wp_print_styles', 'print_emoji_styles');
}
add_action('init', 'disable_emoji');

// 2. 移除不必要的头部信息
remove_action('wp_head', 'wp_generator');           // WordPress 版本号
remove_action('wp_head', 'wlwmanifest_link');       // Windows Live Writer
remove_action('wp_head', 'rsd_link');               // RSD
remove_action('wp_head', 'wp_shortlink_wp_head');   // 短链接

// 3. 禁用 XML-RPC（减少攻击面）
add_filter('xmlrpc_enabled', '__return_false');

// 4. 移除查询字符串
function remove_query_strings($src) {
    if (strpos($src, '?ver=')) {
        $src = remove_query_arg('ver', $src);
    }
    return $src;
}
add_filter('style_loader_src', 'remove_query_strings');
add_filter('script_loader_src', 'remove_query_strings');

// 5. 限制修订版本数量
define('WP_POST_REVISIONS', 3);

// 6. 禁用文章自动保存
define('AUTOSAVE_INTERVAL', 300);   // 5 分钟

// 7. 禁用文章版本控制（极端情况）
// define('WP_POST_REVISIONS', false);

// wp-config.php 安全配置

// 禁用文件编辑器
define('DISALLOW_FILE_EDIT', true);

// 禁用插件和主题安装（生产环境）
// define('DISALLOW_FILE_MODS', true);

// 强制 SSL（后台）
define('FORCE_SSL_ADMIN', true);

// 自动更新
define('WP_AUTO_UPDATE_CORE', 'minor');   // 仅小版本更新

// 文件系统
define('FS_METHOD', 'direct');

// 1. 修改登录 URL（插件：WPS Hide Login）
// 默认：/wp-admin / wp-login.php
// 修改后：/my-secret-login

// 2. 限制登录尝试（插件：Limit Login Attempts Reloaded）
// 或手动添加代码

// 3. 双因素认证（插件：WP 2FA / Google Authenticator）

// 4. 添加登录验证码
function my_login_captcha() {
    ?>
    <p>
        <label for="captcha">What is 3 + 4?</label><br>
        <input type="text" name="captcha" id="captcha" class="input" required>
    </p>
    <?php
}
add_action('login_form', 'my_login_captcha');

function my_verify_login_captcha($user, $password) {
    $answer = $_POST['captcha'] ?? '';
    if ($answer != '7') {
        return new WP_Error('captcha_error', 'Incorrect captcha answer.');
    }
    return $user;
}
add_filter('authenticate', 'my_verify_login_captcha', 20, 3);

// wp-config.php 中添加
define('WP_ALLOW_MULTISITE', true);

// 1. 开启调试模式
// wp-config.php
define('WP_DEBUG', true);
define('WP_DEBUG_LOG', true);
define('WP_DEBUG_DISPLAY', false);

// 查看日志
tail -f /var/www/wordpress/wp-content/debug.log

// 2. 禁用所有插件（通过数据库）
mysql -u root -p wordpress -e "UPDATE wp_options SET option_value='a:0:{}' WHERE option_name='active_plugins';"

// 3. 切换默认主题（通过数据库）
mysql -u root -p wordpress -e "UPDATE wp_options SET option_value='twentytwentyfour' WHERE option_name='template';"
mysql -u root -p wordpress -e "UPDATE wp_options SET option_value='twentytwentyfour' WHERE option_name='stylesheet';"

// 4. 检查 PHP 内存限制
// php.ini 或 wp-config.php
define('WP_MEMORY_LIMIT', '256M');

// 5. 重新上传 WordPress 核心文件
wp core download --force

// "建立数据库连接时出错"

// 1. 检查 wp-config.php 中的数据库信息
define('DB_NAME', 'wordpress');
define('DB_USER', 'wpuser');
define('DB_PASSWORD', 'password');
define('DB_HOST', 'localhost');

// 2. 检查 MySQL 服务
sudo systemctl status mysql
sudo systemctl restart mysql

// 3. 检查数据库用户权限
mysql -u root -p -e "SHOW GRANTS FOR 'wpuser'@'localhost';"

// 4. 测试数据库连接
mysql -u wpuser -p'password' wordpress -e "SELECT 1;"

<?php
/**
 * Plugin Name: My Shortcodes
 * Description: 自定义短代码集合
 * Version: 1.0.0
 * Author: Your Name
 * Text Domain: my-shortcodes
 */

if (!defined('ABSPATH')) exit;

// 按钮短代码 [my_button url="#" text="点击这里" color="blue" size="large"]
function my_button_shortcode($atts) {
    $atts = shortcode_atts(array(
        'url'   => '#',
        'text'  => 'Click Here',
        'color' => 'blue',
        'size'  => 'medium',
        'target' => '_self',
    ), $atts, 'my_button');

    return sprintf(
        '<a href="%s" class="my-btn my-btn-%s my-btn-%s" target="%s">%s</a>',
        esc_url($atts['url']),
        esc_attr($atts['color']),
        esc_attr($atts['size']),
        esc_attr($atts['target']),
        esc_html($atts['text'])
    );
}
add_shortcode('my_button', 'my_button_shortcode');

// 信息框短代码 [my_alert type="info" title="提示"]内容[/my_alert]
function my_alert_shortcode($atts, $content = null) {
    $atts = shortcode_atts(array(
        'type'  => 'info',
        'title' => '',
    ), $atts, 'my_alert');

    $types = array('info', 'success', 'warning', 'error');
    $type = in_array($atts['type'], $types) ? $atts['type'] : 'info';

    $html = '<div class="my-alert my-alert-' . esc_attr($type) . '">';
    if (!empty($atts['title'])) {
        $html .= '<strong>' . esc_html($atts['title']) . '</strong>';
    }
    $html .= '<p>' . wp_kses_post(do_shortcode($content)) . '</p>';
    $html .= '</div>';

    return $html;
}
add_shortcode('my_alert', 'my_alert_shortcode');

// 文章列表短代码 [my_posts category="news" count="5" layout="grid"]
function my_posts_shortcode($atts) {
    $atts = shortcode_atts(array(
        'category' => '',
        'count'    => 5,
        'layout'   => 'list',
    ), $atts, 'my_posts');

    $args = array(
        'post_type'      => 'post',
        'posts_per_page' => intval($atts['count']),
        'orderby'        => 'date',
        'order'          => 'DESC',
    );

    if (!empty($atts['category'])) {
        $args['category_name'] = sanitize_text_field($atts['category']);
    }

    $query = new WP_Query($args);
    $html = '<div class="my-posts my-posts-' . esc_attr($atts['layout']) . '">';

    if ($query->have_posts()) {
        while ($query->have_posts()) {
            $query->the_post();
            $html .= '<div class="my-post-item">';
            $html .= '<h3><a href="' . get_permalink() . '">' . get_the_title() . '</a></h3>';
            $html .= '<p>' . get_the_excerpt() . '</p>';
            $html .= '<span class="date">' . get_the_date() . '</span>';
            $html .= '</div>';
        }
    } else {
        $html .= '<p>暂无文章</p>';
    }

    $html .= '</div>';
    wp_reset_postdata();

    return $html;
}
add_shortcode('my_posts', 'my_posts_shortcode');

// 加载短代码样式
function my_shortcodes_styles() {
    wp_enqueue_style('my-shortcodes', plugin_dir_url(__FILE__) . 'assets/css/shortcodes.css', array(), '1.0.0');
}
add_action('wp_enqueue_scripts', 'my_shortcodes_styles');

<?php
/**
 * Plugin Name: My Custom Post Types
 * Description: 注册自定义文章类型和分类法
 * Version: 1.0.0
 */

if (!defined('ABSPATH')) exit;

// 注册自定义文章类型
function my_register_post_types() {

    // 作品集（Portfolio）
    register_post_type('portfolio', array(
        'labels' => array(
            'name'               => '作品集',
            'singular_name'      => '作品',
            'add_new'            => '添加作品',
            'add_new_item'       => '添加新作品',
            'edit_item'          => '编辑作品',
            'new_item'           => '新作品',
            'view_item'          => '查看作品',
            'search_items'       => '搜索作品',
            'not_found'          => '未找到作品',
            'not_found_in_trash' => '回收站中无作品',
        ),
        'public'          => true,
        'has_archive'     => true,
        'rewrite'         => array('slug' => 'portfolio'),
        'menu_icon'       => 'dashicons-portfolio',
        'supports'        => array('title', 'editor', 'thumbnail', 'excerpt', 'custom-fields', 'comments'),
        'show_in_rest'    => true,
        'capability_type' => 'post',
    ));

    // 产品（Product）
    register_post_type('product', array(
        'labels' => array(
            'name'          => '产品',
            'singular_name' => '产品',
            'add_new'       => '添加产品',
            'edit_item'     => '编辑产品',
        ),
        'public'       => true,
        'has_archive'  => true,
        'rewrite'      => array('slug' => 'product'),
        'menu_icon'    => 'dashicons-cart',
        'supports'     => array('title', 'editor', 'thumbnail', 'excerpt', 'custom-fields'),
        'show_in_rest' => true,
    ));
}
add_action('init', 'my_register_post_types');

// 注册自定义分类法
function my_register_taxonomies() {

    // 作品分类
    register_taxonomy('portfolio_category', 'portfolio', array(
        'labels' => array(
            'name'          => '作品分类',
            'singular_name' => '作品分类',
            'add_new_item'  => '添加作品分类',
        ),
        'hierarchical'      => true,
        'rewrite'           => array('slug' => 'portfolio-category'),
        'show_admin_column' => true,
        'show_in_rest'      => true,
    ));

    // 产品标签
    register_taxonomy('product_tag', 'product', array(
        'labels' => array(
            'name'          => '产品标签',
            'singular_name' => '产品标签',
        ),
        'hierarchical'      => false,
        'rewrite'           => array('slug' => 'product-tag'),
        'show_admin_column' => true,
        'show_in_rest'      => true,
    ));
}
add_action('init', 'my_register_taxonomies');

// 注册自定义元数据
function my_register_meta() {
    register_post_meta('portfolio', 'project_url', array(
        'show_in_rest'  => true,
        'single'        => true,
        'type'          => 'string',
        'auth_callback' => function() { return current_user_can('edit_posts'); },
    ));

    register_post_meta('portfolio', 'client_name', array(
        'show_in_rest'  => true,
        'single'        => true,
        'type'          => 'string',
        'auth_callback' => function() { return current_user_can('edit_posts'); },
    ));

    register_post_meta('product', 'price', array(
        'show_in_rest'  => true,
        'single'        => true,
        'type'          => 'string',
        'auth_callback' => function() { return current_user_can('edit_posts'); },
    ));

    register_post_meta('product', 'sku', array(
        'show_in_rest'  => true,
        'single'        => true,
        'type'          => 'string',
        'auth_callback' => function() { return current_user_can('edit_posts'); },
    ));
}
add_action('init', 'my_register_meta');