OAuth 1.0 3-legged server side flow (motorsportreg example)

oauth_node_example.js

'use strict';

process.env.NODE_TLS_REJECT_UNAUTHORIZED = '0';

var localtunnel = require('localtunnel');
var request = require('request');

var qs = require('querystring');
var url = require('url');
var http = require('http');

const apiUrl = 'https://demo.motorsportreg.com:9201/';
const requestUrl = apiUrl + 'rest/tokens/request';
const accessUrl = apiUrl + 'rest/tokens/access';
const meUrl = apiUrl + 'rest/me.json';
const consumerKey = '*';
const consumerSecret = '*';
const authorizePage = 'https://demo.motorsportreg.com/index.cfm/event/oauth';

const port = 8000;

localtunnel(port, function(err, tunnel) {
  if (err) { throw err; }

  console.log('tunnel url:', tunnel.url);

  var oauth = {
    callback: tunnel.url,
    'consumer_key': consumerKey,
    'consumer_secret': consumerSecret
  };
  /* leg 1: request token */
  request.post({url: requestUrl, oauth: oauth}, function (e, r, body) {
    if (r.statusCode !== 200) { throw r.headers; }

    var reqData = qs.parse(body);
    console.log('reqData', reqData);

    /* leg 2: authorize */
    console.log('***');
    console.log('authorize page (Cmd + double click to open):', authorizePage + '?' + body);
    console.log('***');

    http.createServer(function(req, res) {
      var parsedUrl = url.parse(req.url, true);
      if (parsedUrl.pathname === '/') { /* skip favicon.ico request */
        /* leg 3: access token */
        var authData = parsedUrl.query;
        console.log('authData', authData);
        var oauth = {
          'consumer_key': consumerKey,
          'consumer_secret': consumerSecret,
          token: authData['oauth_token'],
          'token_secret': reqData['oauth_token_secret'],
          verifier: authData['oauth_verifier']
        };
        request.post({url: accessUrl, oauth: oauth}, function (e, r, body) {
          if (r.statusCode !== 200) { throw r.headers; }

          var permData = qs.parse(body);
          console.log('permData', permData);
          var oauth = {
            'consumer_key': consumerKey,
            'consumer_secret': consumerSecret,
            token: permData['oauth_token'],
            'token_secret': permData['oauth_token_secret'],
          };
          request.get({url: meUrl, oauth: oauth, json: true}, function(e, r, body) {
            if (r.statusCode !== 200) { throw r.headers; }

            console.log('user', JSON.stringify(body.response));
          });
        });
      }

      res.writeHead(200, {'Content-Type': 'application/json'});
      res.end(JSON.stringify({url: req.url, headers: req.headers}, null, 2));
    }).listen(port, function() {
      console.log('listening to', port);
    });
  });
});

Don't forget to install packages:
npm install --save localtunnel request