node_mongo_connection.js

/**
 * Basic script to start with 
 * mongodb (Connection steps 
 * and Read operation)
 */

//  Step-1: Get the MongoClient (Driver for node)
const MongoClient = require("mongodb").MongoClient;

// Step-2: Store mongo server url
let url = 'mongodb://localhost:27017';


// Step-5: Custom function
const getAllData = function(client, callback) {

    // Step-6:  Select db
    let db = client.db("analytics");
    // Step-7: Select collection
    let collection = db.collection("sites");

    // Step-8: Call functions on the collection
    collection.find({
        "domain": "debojyoti.xyz"
    }).toArray((err, docs) => {
        console.log(docs);
        callback();
    })
}

const config = {
    useNewUrlParser: true
};


//  Step-3: Call connect using the client
MongoClient.connect(url, config, (err, client) => {
    // Step-4: Send the client instance to custom function
    getAllData(client, () => {
        console.log("Closing db connection");
        client.close();
    });
});