old_contents: var express = require('express');
  var path = require('path');
  var favicon = require('serve-favicon');
  var logger = require('morgan');
  var cookieParser = require('cookie-parser');
  
  var bodyParser = require('body-parser');var express = require('express');
  var router = express.Router();
  
  var mongoose = require('mongoose');
  var jwt = require('jsonwebtoken');
  var config = require('../config.js');
  var User = require('../models/user.js');
  
  /* GET users listing. */
  router.get('/', function(req, res, next) {
      User.find({}, function(err, users) {
          res.json(users);
      })
       //res.send('respond with a resource');
  });
  
  module.exports = router;
  
new_contents: var express = require('express');
  var path = require('path');
  var favicon = require('serve-favicon');
  var logger = require('morgan');
  var cookieParser = require('cookie-parser');
  
  var bodyParser = require('body-parser');var express = require('express');
  var router = express.Router();
  
  var mongoose = require('mongoose');
  var jwt = require('jsonwebtoken');
  var config = require('../config.js');
  var User = require('../models/user.js');
  
  router.use(function(req, res, next) {
      var token = req.body.token || req.query.token || req.headers['x-access-token'];
  
      if(token) {
          jwt.verify(token, 'supersecret', function(err, decoded) {
              if(err) {
                  return res.json({
                      success: false,
                      message: 'Failed to authenticate'
                  });
              } else {
                  req.decoded = decoded;
                  next();
              }
          });
      } else {
          return res.status(403).send({
                  success: false,
                  message: 'No token provided'
          });
      }
  });
  
  /* GET users listing. */
  router.get('/', function(req, res, next) {
      User.find({}, function(err, users) {
          res.json(users);
      });
  });
  
  module.exports = router;
  
subject: Add authentication to the users file