以下为Woodpress主题目录下function.php中可添加的优化项，请根据需要进行修改。注意备份

删除api.w.org

add_action('after_setup_theme', function(){
    remove_action( 'wp_head', 'rest_output_link_wp_head', 10 );
});

禁用XML-RPC

/**禁用XML-RPC*/
add_filter( 'xmlrpc_enabled', '__return_false' );

删除url/?后的参数，命中CDN缓存

/**删除js及css的版本查询字符串*/
function _remove_script_version ( $src ){
  $parts = explode( '?', $src );
  return $parts[0];
}
add_filter( 'script_loader_src', '_remove_script_version', 15, 1 );
add_filter( 'style_loader_src', '_remove_script_version', 15, 1 );

WordPress完全禁用REST API（最新版）

add_filter( 'rest_authentication_errors', function( $access ) {
    if ( !is_user_logged_in() ) {
        return new WP_Error( 'rest_cannot_acess', 'REST API不再提供访问', array( 'status' => 403 ) );
    }
});

禁用未登录的用户

/*禁用未登录的用户*/
add_filter( 'rest_api_init', 'lxtx_rest_only_for_authorized_users', 99 );
function lxtx_rest_only_for_authorized_users($wp_rest_server){
    if ( !is_user_logged_in() ) {
        wp_die('非法操作！');
    }
}

禁止查看用户id

/*禁止查看用户id*/
function redirect_to_home_if_author_parameter() {

    $is_author_set = get_query_var( 'author', '' );
    if ( $is_author_set != '' && !is_admin()) {
        wp_redirect( home_url(), 301 );
        exit;
    }
}
add_action( 'template_redirect', 'redirect_to_home_if_author_parameter' );

关闭rss feed功能

function disable_all_feeds() {
wp_die(__('<h1>本博客不提供Feed，请访问网站<a href="'.get_bloginfo('url').'">首页</a>！</h1>'));
}
add_action('do_feed', 'disable_all_feeds', 1);
add_action('do_feed_rdf', 'disable_all_feeds', 1);
add_action('do_feed_rss', 'disable_all_feeds', 1);
add_action('do_feed_rss2', 'disable_all_feeds', 1);
add_action('do_feed_atom', 'disable_all_feeds', 1);
remove_action( 'wp_head', 'feed_links_extra', 3 );
remove_action( 'wp_head', 'feed_links', 2 );

移除不必要的信息,wordpress版本

remove_action( 'wp_head', 'wp_generator' ) ;
remove_action( 'wp_head', 'wlwmanifest_link' ) ;
remove_action( 'wp_head', 'rsd_link' ) ;

取消评论框下的HTML标签和属性

add_filter( 'pre_comment_content', 'wp_specialchars' );

隐藏登陆界面错误提示

/*隐藏登陆界面错误提示*/
function no_errors_please(){
return 'GET OFF MY LAWN !! RIGHT NOW !!';
}
add_filter( 'login_errors', 'no_errors_please' );

去除分类标志代码

//去除分类标志代码
add_action( 'load-themes.php',  'no_category_base_refresh_rules');
add_action('created_category', 'no_category_base_refresh_rules');
add_action('edited_category', 'no_category_base_refresh_rules');
add_action('delete_category', 'no_category_base_refresh_rules');
function no_category_base_refresh_rules() {
    global $wp_rewrite;
    $wp_rewrite -> flush_rules();
}
// register_deactivation_hook(__FILE__, 'no_category_base_deactivate');
// function no_category_base_deactivate() {
//  remove_filter('category_rewrite_rules', 'no_category_base_rewrite_rules');
//  // We don't want to insert our custom rules again
//  no_category_base_refresh_rules();
// }
// Remove category base
add_action('init', 'no_category_base_permastruct');
function no_category_base_permastruct() {
    global $wp_rewrite, $wp_version;
    if (version_compare($wp_version, '3.4', '<')) {
        // For pre-3.4 support
        $wp_rewrite -> extra_permastructs['category'][0] = '%category%';
    } else {
        $wp_rewrite -> extra_permastructs['category']['struct'] = '%category%';
    }
}
// Add our custom category rewrite rules
add_filter('category_rewrite_rules', 'no_category_base_rewrite_rules');
function no_category_base_rewrite_rules($category_rewrite) {
    //var_dump($category_rewrite); // For Debugging
    $category_rewrite = array();
    $categories = get_categories(array('hide_empty' => false));
    foreach ($categories as $category) {
        $category_nicename = $category -> slug;
        if ($category -> parent == $category -> cat_ID)// recursive recursion
            $category -> parent = 0;
        elseif ($category -> parent != 0)
            $category_nicename = get_category_parents($category -> parent, false, '/', true) . $category_nicename;
        $category_rewrite['(' . $category_nicename . ')/(?:feed/)?(feed|rdf|rss|rss2|atom)/?$'] = 'index.php?category_name=$matches[1]&feed=$matches[2]';
        $category_rewrite['(' . $category_nicename . ')/page/?([0-9]{1,})/?$'] = 'index.php?category_name=$matches[1]&paged=$matches[2]';
        $category_rewrite['(' . $category_nicename . ')/?$'] = 'index.php?category_name=$matches[1]';
    }
    // Redirect support from Old Category Base
    global $wp_rewrite;
    $old_category_base = get_option('category_base') ? get_option('category_base') : 'category';
    $old_category_base = trim($old_category_base, '/');
    $category_rewrite[$old_category_base . '/(.*)$'] = 'index.php?category_redirect=$matches[1]';
    //var_dump($category_rewrite); // For Debugging
    return $category_rewrite;
}
// Add 'category_redirect' query variable
add_filter('query_vars', 'no_category_base_query_vars');
function no_category_base_query_vars($public_query_vars) {
    $public_query_vars[] = 'category_redirect';
    return $public_query_vars;
}
// Redirect if 'category_redirect' is set
add_filter('request', 'no_category_base_request');
function no_category_base_request($query_vars) {
    //print_r($query_vars); // For Debugging
    if (isset($query_vars['category_redirect'])) {
        $catlink = trailingslashit(get_option('home')) . user_trailingslashit($query_vars['category_redirect'], 'category');
        status_header(301);
        header("Location: $catlink");
        exit();
    }
    return $query_vars;
}