index.js

const MongoClient = require('mongodb').MongoClient;
const url = "mongodb://mongo:27017/mydb";
const query = { address: "Highway 37" };
const myDoc = { name: "Company Inc", address: "Highway 37" };

const p = new Promise((resolve, reject) => {
    MongoClient.connect(url, (err, db) => {
        if (err) reject(err);
        console.log("Database created!");
        resolve(db);
    });
});

p.then(db => {
    return new Promise((resolve, reject) => {
        const dbo = db.db("mydb");
        dbo.createCollection("customers", function(err, res) {
            if (err) reject(err);
            console.log("Collection created!");
            resolve(db);
        });
    })
})
.then(db => {
    return new Promise((resolve, reject) => {
        const dbo = db.db("mydb");
        dbo
            .collection("customers")
            .insertOne(myDoc, function(err, res) {
                if (err) reject(err);
                console.log("1 document inserted");
                resolve(db);
            });
    });
})
.then(db => {
    return new Promise((resolve, reject) => {
        const dbo = db.db("mydb");
        dbo
            .collection("customers")
            .find(query)
            .toArray(function(err, result) {
                if (err) reject(err);
                console.log('This is what we found:', result);
                resolve(db);
            });
    });
})
.then(db => {
    db.close();
})
.catch(error => {
    console.error(error);
});