const { MongoClient } = require('mongodb'); let World, Fortune; const projection = { _id:0 }; MongoClient.connect('mongodb://tfb-database:27017', { useNewUrlParser:true }, (err, ctx) => { const DB = ctx.db('hello_world'); Fortune = DB.collection('fortune'); World = DB.collection('world'); }); exports.fortunes = () => Fortune.find({}, { projection }).toArray(); exports.find = id => World.findOne({ id }, { projection }); exports.update = obj => World.replaceOne({ id:obj.id }, obj);