code: function (req, res, next) {
      var profileUrl = 'https://api.foursquare.com/v2/users/self';
      var params = {
        v: '20140806',
        oauth_token: req.accessToken
      };
  
      request.get({ url: profileUrl, qs: params, json: true }, function(err, response, profile) {
        if (err) {
          res.status(500).send(err);
          return;
        }
        req.profile = profile.response.user;
        next();
      });
    }
docs: Step 2. Retrieve information about the current user.