old_contents: 'use strict';
  
  const express = require('express');
  const app = express();
  const mongoose = require('mongoose');
  const morgan = require('morgan');
  const errorHandler = require('./lib/error_handling');
  
  const dbPort = process.env.MONGOLAB_URI || 'mongodb://localhost/dev_db';
  
  mongoose.connect(dbPort);
  
  const iceCreamRouter = require('./route/icecream_routes');
  const milkShakeRouter = require('./route/milkshake_routes');
  
  app.use(morgan('dev'));
  app.use('/icecream', iceCreamRouter);
  app.use('/milkshake', milkShakeRouter);
  
  app.use(errorHandler);
  
  app.use((req, res) => {
    res.status(404).json({message: 'not found'});
  });
  
  
  app.listen(3000, () => {
    console.log('up on 3000');
  });
  
new_contents: 'use strict';
  
  const express = require('express');
  const app = express();
  const mongoose = require('mongoose');
  const morgan = require('morgan');
  const errorHandler = require('./lib/error_handling');
  
  const dbPort = process.env.MONGODB_URI || 'mongodb://localhost/dev_db';
  
  mongoose.connect(dbPort);
  
  const iceCreamRouter = require('./route/icecream_routes');
  const milkShakeRouter = require('./route/milkshake_routes');
  
  app.use(morgan('dev'));
  app.use('/icecream', iceCreamRouter);
  app.use('/milkshake', milkShakeRouter);
  
  app.use(errorHandler);
  
  app.use((req, res) => {
    res.status(404).json({message: 'not found'});
  });
  
  
  app.listen(3000, () => {
    console.log('up on 3000');
  });
  
subject: change name of mongdb var