text: const mongoose = require('mongoose');
  
  mongoose.set('debug', true);
  mongoose.Promise = Promise;
  mongoose.connect(process.env.DB || 'mongodb://localhost/warbler', {
    keepAlive: true,
    useCreateIndex: true,
    useFindAndModify: false,
    useNewUrlParser: true,
    useUnifiedTopology: true,
  });
  
  module.exports.UserModel = require('./User');
  module.exports.MessageModel = require('./Message');
  