Webservice with wordpress login

<?php

require ("../wp-load.php");

if($_REQUEST['pass'] != "" && $_REQUEST['email'] != "") {

$ar = wp_authenticate_username_password("", $_REQUEST['email'], $_REQUEST['pass']);

$class_name = get_class ($ar);

if ( $class_name == "WP_User" ) {

$user_id = $ar->data->ID;

$arr = array(

"id" => $user_id,

"email" => $ar->data->user_email,

"name" => $ar->data->display_name,

);

$ar = array ("result" => 0, "message" => $arr);

echo json_encode($ar);

exit();

} else {

$ar = array ("result" => 0, "message" => "Email or Password is Wrong");

echo json_encode($ar);

exit();

}

} else {

$ar = array ("result" => 0, "message" => "Require Field Missing");

echo json_encode($ar);

exit();

}