How To Connect MongoDB Database in a Node.js Applications ?

To connect MongoDB to a Node.js application, you can follow a simple process using the Mongoose library, which provides a flexible way to work with MongoDB. Mongoose acts as an Object Data Modeling (ODM) library, making it easier to structure and interact with MongoDB from Node.js.

Prerequisites:

• Node js
• MongoDB

Approach

To connect MongoDB to the Node application, we will

• First, initialize the node.js project in the particular folder on your machine.
• install Mongoose npm package and import
• After this create a connection to the database using mongoose.connect method

Steps to Connect MongoDB Database with Node Application

Step 1: Create a project folder using the following command.

mkdir mongodb-connection
cd mongodb-connection

Step 2: Initialize the node project using the following command.

npm init -y

Step 3: Install the required dependencies

npm i express mongodb mongoose

Project Structure

Our file structure will look like the following:

Dependencies

"dependencies": {
    "express": "^4.19.2",
    "mongodb": "^6.7.0",
    "mongoose": "^8.4.1",
}

Example: This example demonstrates connection of mongo with node js.

// index.js

const express = require("express");
const app = express();
console.log("App listen at port 5000");

// To connect with your MongoDB database
const mongoose = require("mongoose");
// Connecting to database
mongoose.connect(
    "mongodb://localhost:27017/",
    {
        dbName: "yourDB-name",
        useNewUrlParser: true,
        useUnifiedTopology: true,
    },
    (err) =>
        err ? console.log(err) : console.log(
            "Connected to yourDB-name database")
);

To start the application run the following command.

nodemon index.js