如何限制 WordPress 的登入嘗試？ 【你該這麼做嗎？

 <?php /** * CLASS LIMIT LOGIN ATTEMPTS * Prevent Mass WordPress Login Attacks by setting locking the system when login fails. * To be added in functions.php or as an external file. */ if ( ! class_exists( 'Limit_Login_Attempts' ) ) {    class Limit_Login_Attempts {        var $failed_login_limit = 3;                    //Number of authentication accepted        var $lockout_duration   = 1200;                 //Stop authentification process for 30 minutes: 60*30 = 1800        var $transient_name     = 'attempted_login';    //Transient used        public function __construct() {            add_filter( 'authenticate', array( $this, 'check_attempted_login' ), 30, 3 );            add_action( 'wp_login_failed', array( $this, 'login_failed' ), 10, 1 );        }        /**        * Lock login attempts of failed login limit is reached        */        public function check_attempted_login( $user, $username, $password ) {            if ( get_transient( $this->transient_name ) ) {                $datas = get_transient( $this->transient_name );                if ( $datas['tried'] >= $this->failed_login_limit ) {                    $until = get_option( '_transient_timeout_' . $this->transient_name );                    $time = $this->when( $until );                    //Display error message to the user when limit is reached                    return new WP_Error( 'too_many_tried', sprintf( __( '<strong>ERROR</strong>: You have reached authentification limit, you will be able to try again in %1$s.' ) , $time ) );                }            }            return $user;        }        /**        * Add transient        */        public function login_failed( $username ) {            if ( get_transient( $this->transient_name ) ) {                $datas = get_transient( $this->transient_name );                $datas['tried']++;                if ( $datas['tried'] <= $this->failed_login_limit )                    set_transient( $this->transient_name, $datas , $this->lockout_duration );            } else {                $datas = array(                    'tried'     => 1                );                set_transient( $this->transient_name, $datas , $this->lockout_duration );            }        }        /**        * Return difference between 2 given dates        * @param  int      $time   Date as Unix timestamp        * @return string           Return string        */        private function when( $time ) {            if ( ! $time )                return;            $right_now = time();            $diff = abs( $right_now - $time );            $second = 1;            $minute = $second * 60;            $hour = $minute * 60;            $day = $hour * 24;            if ( $diff < $minute )                return floor( $diff / $second ) . ' secondes';            if ( $diff < $minute * 2 )                return "about 1 minute ago";            if ( $diff < $hour )                return floor( $diff / $minute ) . ' minutes';            if ( $diff < $hour * 2 )                return 'about 1 hour';            return floor( $diff / $hour ) . ' hours';        }    } } //Enable it: new Limit_Login_Attempts(); ?>