Attempt to get temperature from Withings Smart Body Analyser (Now sold as Nokia Body+) to be displayed within Homekit. Ended up giving up as it appears the temperature information is only updated when you step on the scale, which kind of defeats the purpose.

config.json

{
    "bridge": {
        "name": "Homebridge",
        "username": "CC:22:3D:E3:CE:30",
        "port": 52430,
        "pin": "031-45-154"
    },

    "description": "Config file",

    "accessories": [
        {
            "accessory": "Withings",
            "name": "Scales",
            "email": "",
            "password": "",
            "device_id":"",
            "user_id":""
        }
    ]
}

index.js

var Service, Characteristic;
var request = require('request');
// var withingsApi = require("withings-api"); // Doesn't support Weather and CO2 levels

var temperatureService;
var url;
var humidity = 0;
var temperature = 0;


const DEF_MIN_TEMPERATURE = -100,
      DEF_MAX_TEMPERATURE = 100;

module.exports = function (homebridge) {
    Service = homebridge.hap.Service;
    Characteristic = homebridge.hap.Characteristic;
    homebridge.registerAccessory("homebridge-withings", "Withings", Withings);
};


function Withings(log, config) {
    this.log = log;

    this.email = config.email;
    this.password = config.password;
    this.name = config.name;
    this.manufacturer = config.manufacturer || "Withings";
    this.model = config.model || "Unknown";
    this.serial = config.serial || "Unknown";
    this.device_id = config.device_id;
    this.user_id = config.user_id;
    this.minTemperature = config.min_temp || DEF_MIN_TEMPERATURE;
    this.maxTemperature = config.max_temp || DEF_MAX_TEMPERATURE;
}

Withings.prototype = {

    getState: function (callback) {
      var authUrl = 'https://account.health.nokia.com/connectionwou/account_login?r=https%3A%2F%2Fdashboard.health.nokia.com%2F';
      var measureUrl = 'https://scalews.health.nokia.com/cgi-bin/v2/measure';
      var j = request.jar();
      var withings = this; // Required to ensure that this can be accessed within callbacks.

      var enddate = Math.round(new Date().getTime() / 1000); // time now
      var startdate = enddate - (7 * 24 * 3600); // week ago

      withings.log('Authenticating with Withings...');
      withings.log('Email: ' + withings.email);
      request.post(authUrl,{
                              form: {
                                email: withings.email, 
                                password: withings.password
                              }, 
                              jar: j
                            })
             .on('response', function (r) {
               var cookies = j.getCookieString(authUrl);
               var reg = /session_key=(.*)/;

               var sessionKey = cookies.match(reg)[1];
                //console.log(sessionKey);
               withings.log('Device ID: '+ withings.device_id);
               withings.log('User ID: '+ withings.user_id);
               withings.log('Attempting to retrieve temperature...');
               
               var headersMeasure = {
                      'Origin': 'https://dashboard.health.nokia.com',
                      'Accept-Encoding': 'gzip, deflate, br',
                      'Accept-Language': 'ru-RU,ru;q=0.9,en-US;q=0.8,en;q=0.7',
                      'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/66.0.3359.181 Safari/537.36',
                      'Content-Type': 'text/plain;charset=UTF-8',
                      'Accept': '*/*',
                      'Referer': 'https://dashboard.health.nokia.com/',
                      'Connection': 'keep-alive',
                      'DNT': '1',
                      'Cookie': 'session_key='+sessionKey
                      };
               
               var dataMeasure = 'action=getmeashf&meastype=35%2C12&deviceid='+ withings.device_id +'&userid='+ withings.user_id +'&startdate='+ startdate +'&enddate='+ enddate +'&appname=hmw&apppfm=web&appliver=92d98b4';
               
               request({
                        url: measureUrl,
                        method: 'POST',
                        gzip: true,
                        headers: headersMeasure,
                        body: dataMeasure
               }, function(error, response, body) {
                 withings.log('Response received...');
                 var temperature = null;
                 var json = JSON.parse(body);
                 if (error) {
                   withings.log('HTTP bad response (' + measureUrl + '): ' + error.message);
                 }
                 else if (parseInt(json.status) !== 0) {
                   withings.log('Body: '+ body);
                   withings.log('Status: ' + json.status);
                   try {
                     throw 'Reponse Unsuccessful (' + measureUrl + '):' + json.status;
                   } catch (respErr) {
                     withings.log(respErr.message);
                     error = respErr;
                   }
                 }
                 else {
                   try {
                     temperature = json.body.series[1].data[0].value;
                     withings.log('Temperature: ' + temperature);
                     if (temperature < withings.minTemperature || temperature > withings.maxTemperature || isNaN(temperature)) {
                       throw "Invalid value received";
                     }
                     withings.log('HTTP successful response: ' + body);
                   } catch (parseErr) {
                     withings.log('Error processing received information: ' + parseErr.message);
                     error = parseErr;
                   }
                    console.log(json);
                 }
                 callback(error, temperature);
               });
           });
    },

    getServices: function () {
        this.informationService = new Service.AccessoryInformation();
        this.informationService
                .setCharacteristic(Characteristic.Manufacturer, this.manufacturer)
                .setCharacteristic(Characteristic.Model, this.model)
                .setCharacteristic(Characteristic.SerialNumber, this.serial);

        this.temperatureService = new Service.TemperatureSensor(this.name);
        this.temperatureService
                .getCharacteristic(Characteristic.CurrentTemperature)
                .on('get', this.getState.bind(this))
                .setProps({
                    minValue: this.minTemperature,
                    maxValue: this.maxTemperature
                });

        return [this.informationService, this.temperatureService];
    }
};

How can I get device_id ?