connot find client.user

[expandboard]

when use Ponte as embedded in nodejs code and i want to authorize for publishing, client.user is not found in client object while publish payload in MQTT.

var authorizePublish = function(client, topic, payload, callback) {
		callback(null, client.user == topic.split('/')[1]);
	} 

client.id is Ok but about client.user it is not included and it's undefined.

you can find whole code below;

       const debug = require('debug')('iok-express:ponte');
       const ponte = require('ponte');
       var config = require('../config/ponte.js');
       var mongoose = require('mongoose');
       var Thing = require("../models/thing");

		// Accepts the connection if the username and password are valid
	var authenticate = function (client, username, password, callback) {
		Thing.findOne({clientid: client.id}, function(err, things) {
			if (err) {
				console.log('Quering thing failed.');
				console.log(err);
				callback(null, false);
				return;
			}
			if (!things) {
				console.log("ClientID Not found, Client ID:" + client.id);
				callback(null, false);
				return;
			}  
			if (username == things.config.username && password == things.config.password)	{
				console.log('Successful MQTT credintial. Client ID:' + client.id);
				callback(null, true);
				return;
			}
			else {
				console.log('Unsuccessful MQTT credintial. Client ID:' + client.id + '  ,Username:' + username + '  ,Password:' + password);
				callback(null, false);	
			}
		});
	}
	
	var authorizePublish = function(client, topic, payload, callback) {
		callback(null, client.id == topic.split('/')[1]);
	}
	
	var authorizeSubscribe = function(client, topic, callback) {
		callback(null, client.id == topic.split('/')[1]);
	}
	
	config.mqtt.authenticate = authenticate;
	config.mqtt.authorizePublish = authorizePublish;
	config.mqtt.authorizeSubscribe = authorizeSubscribe;
	
	var server = ponte(config);
		
	server.on("updated", function(resource, buffer) {
		console.log("Resource Updated", resource, buffer);
	});