<?php
//api.php
$key = $_SESSION["csrf-key"];
$api = new Webix\Remote\Server($key);
//add function
$api->setMethod("add", function($a, $b){
	return $a + $b;
});
$api->setMethod("error", function(){
	throw new \Exception("Dummy");
});
//add static value
$api->setData("user", "1");
//add class
class DataDao{
	public function mul($a, $b){
		return $a * $b;
	}
}
$api->setClass("data", new DataDao());
$api->end();

<script src="http://cdn.webix.com/edge/webix.js"></script>
<script src="api.php"></script>
<script>
//async by default
var res = webix.remote.data.mul(2, 4);
res.then((data) => alert(data));  //8
//still, can be sync when necessary
var sum = webix.remote.add(2, 4); //6
alert(sum);
</script>