Mongo connection using promises

mongo-promise.js

'use strict';
const mongoClient = require('mongodb').MongoClient;

const url = 'mongodb://localhost:27017/test';

mongoClient.connect(url)
  .then(conn => {
    return conn.collection('restaurants')
      .find().limit(10).toArray()
      .then(out => console.log(out))
      .then(() => conn.close())
  })