old_contents: require('dotenv').config();
  var https = require('https');
  var app = require('express')();
  var ringcentral = require('ringcentral');
  
  // Configure Mustache
  var mustacheExpress = require('mustache-express');
  app.engine('mustache', mustacheExpress());
  app.set('view engine', 'mustache');
  app.set('views', __dirname + '/views');
  
  // Start HTTP server
  var server = null;
  var port = process.env.MY_APP_PORT;
  var useTls = process.env.MY_APP_TLS_ENABLED > 0 ? true : false;
  
  if (useTls) {
    var tls = require('tls'),
        fs = require('fs');
    server = https.createServer({
      key: fs.readFileSync(process.env.MY_APP_TLS_PRIVATE_KEY),
      cert: fs.readFileSync(process.env.MY_APP_TLS_PUBLIC_CERT)
    }, app).listen(port, function() {
      console.log('LISTEN_HTTPS ' + port);    
    });
  } else {
    server = require('http').Server(app);
    server.listen(port, function() {
      console.log('LISTEN_HTTP ' + port);    
    });
  }
  
  // Start RingCentral SDK
  var rcsdk = new ringcentral({
    server: process.env.RC_APP_SERVER_URL,
    appKey: process.env.RC_APP_KEY,
    appSecret: process.env.RC_APP_SECRET
  });
  
  app.get('/', function(req, res) {
    // Get token for display after OAuth
    token = rcsdk.platform().auth().data();
    token_json = token['access_token'] ? JSON.stringify(token, null, ' ') : '';
  
    // Render home page with params
    res.render('index', {
      authorize_uri: rcsdk.platform().authUrl({
        redirectUri: process.env.RC_APP_REDIRECT_URL
      }),
      redirect_uri: process.env.RC_APP_REDIRECT_URL,
      token_json: token_json
    });
  });
  
  app.get('/callback', function(req, res) {
    if (req.query.code) {
      rcsdk.platform()
        .login({
          code: req.query.code,
          redirectUri: process.env.RC_APP_REDIRECT_URL
        })
        .then(function(response) {
          console.log('logged_in');
          res.send('');
        })
        .catch(function(e) {
          console.log('ERR ' + e.message  || 'Server cannot authorize user');
          res.send('');
        });
    } else {
      res.send('');
    }
  });
  
new_contents: require('dotenv').config();
  var app = require('express')();
  var ringcentral = require('ringcentral');
  
  // Configure Mustache
  var mustacheExpress = require('mustache-express');
  app.engine('mustache', mustacheExpress());
  app.set('view engine', 'mustache');
  app.set('views', __dirname + '/views');
  
  // Start HTTP server
  var server = null;
  var port = process.env.MY_APP_PORT;
  var useTls = process.env.MY_APP_TLS_ENABLED > 0 ? true : false;
  
  if (useTls) {
    var fs = require('fs');
    server = require('https')
      .createServer({
        key: fs.readFileSync(process.env.MY_APP_TLS_PRIVATE_KEY),
        cert: fs.readFileSync(process.env.MY_APP_TLS_PUBLIC_CERT)
      }, app)
      .listen(port, function() {
        console.log('LISTEN_HTTPS ' + port);    
      });
  } else {
    server = require('http')
      .Server(app)
      .listen(port, function() {
        console.log('LISTEN_HTTP ' + port);    
      });
  }
  
  // Start RingCentral SDK
  var rcsdk = new ringcentral({
    server: process.env.RC_APP_SERVER_URL,
    appKey: process.env.RC_APP_KEY,
    appSecret: process.env.RC_APP_SECRET
  });
  
  app.get('/', function(req, res) {
    // Get token for display after OAuth
    token = rcsdk.platform().auth().data();
    token_json = token['access_token'] ? JSON.stringify(token, null, ' ') : '';
  
    // Render home page with params
    res.render('index', {
      authorize_uri: rcsdk.platform().authUrl({
        redirectUri: process.env.RC_APP_REDIRECT_URL
      }),
      redirect_uri: process.env.RC_APP_REDIRECT_URL,
      token_json: token_json
    });
  });
  
  app.get('/callback', function(req, res) {
    if (req.query.code) {
      rcsdk.platform()
        .login({
          code: req.query.code,
          redirectUri: process.env.RC_APP_REDIRECT_URL
        })
        .then(function(response) {
          console.log('logged_in');
          res.send('');
        })
        .catch(function(e) {
          console.log('ERR ' + e.message  || 'Server cannot authorize user');
          res.send('');
        });
    } else {
      res.send('');
    }
  });
  
subject: update style