MQTT connection options

Here is the code that works without error:

var
    led = NodeMCU.D7,
    relay = NodeMCU.D6;

pinMode(led, "output");
pinMode(relay, "output");



function onInit() {
    setupWifi();
    setLed(led, 0);
}



function setupWifi() {
    var
        ssid = "ssid",
        options = {
            password: "password"
        },
        wifi = require("Wifi");


    wifi.connect(ssid, options, function() {
        print(wifi.getIP());

        server = "192.168.2.10";
        mqtt = require("MQTT").create(server);
        mqtt.connect();

        mqtt.on('connected', function() {
            mqtt.publish('esp8266/status', 'sonoff01 start');
            mqtt.subscribe("esp8266/sonoff01");

        });

        mqtt.on('publish', function(pub) {
            mqtt.publish('esp8266/status', 'sonoff01 ' + pub.message);

            switch (pub.message) {
                case 'on':
                    setLed(led, 1);
                    setRelay(relay, 1);
                    break;
                case 'off':
                    setLed(led, 0);
                    setRelay(relay, 0);
                    break;
            }
        });

    });
}




function setLed(led, state) {
    state = !state;
    digitalWrite(led, state);
}

function setRelay(relay, state) {
    digitalWrite(relay, state);
}

Here is what process.memory() shows:

process.memory();
={ "free": 849, "usage": 851, "total": 1700, "history": 434 }

Change line 31 from:

mqtt.connect();

to:

mqtt.connect({client_id:"booger"});

This is the result:

Running onInit()...
{
  "ip": "192.168.2.16",
  "netmask": "255.255.255.0",
  "gw": "192.168.2.1",
  "mac": "60:01:94:07:ab:1e"
 }
Client connected
Uncaught Error: Function "write" not found!
 at line 1 col 35
....log("Client connected");a.write(b.mqttConnect(b.client_id))...
                              ^
in function "e" called from line 3 col 353
..."close")});b.client=a};a?e():a=require("net").connect({host:...
                              ^
in function "connect" called from line 1 col 109
...onnect({client_id:'booger'}),mqtt.on('connected',function(){...
                              ^
in function called from system

Here is what process.memory() shows:

process.memory();
={ "free": 1120, "usage": 580, "total": 1700, "history": 436 }