Get user role in WordPress

get-user-role.php

<?php
/*
 * Get user's role
 *
 * If $user parameter is not provided, returns the current user's role.
 * Only returns the user's first role, even if they have more than one.
 * Returns false on failure.
 *
 * @param  mixed       $user User ID or object.
 * @return string|bool       The User's role, or false on failure.
 */
function km_get_user_role( $user = null ) {

	$user = $user ? new WP_User( $user ) : wp_get_current_user();

	return $user->roles ? $user->roles[0] : false;
}

//Disallow direct access
defined( 'ABSPATH' ) or die( 'No Access' );

add_filter( 'wp_headers', 'remove_headers', 10000 );
function remove_headers( $headers ) {
    unset($headers['Pragma']);
    unset($headers['Expires']);
    unset($headers['Cache-Control']);
    $headers['User-Role'] = km_get_user_role();
    return $headers;
}