Set up Node.js & connect to a MongoDB Database Using Node.js

 In this article, you will learn to install Node.js and then connect to a MongoDB database using Node.js step-by-step. 

Follow the below steps to learn how to install Node.js and then connect Node.js to a MongoDB database. 

Step 1: Install Nodejs

To set up Node.js on your computer, follow these steps:

• Go to the official Node.js website at https://nodejs.org

• Click the "Download" button for the LTS (Long Term Support) version or the current version, depending on your needs.

• Choose the appropriate installer for your operating system (Windows, Mac, or Linux).

• Run the installer and follow the installation instructions.

• Once the installation is complete, you can open a terminal or command prompt and type "node -v" to check that Node.js is installed correctly.

Step 2: Install the MongoDB Node.js Driver

To install the MongoDB Node.js Driver, follow these steps:

• Open a terminal or command prompt.

• Navigate to your project directory.

• Type the following command to install the MongoDB Node.js Driver using npm (Node Package Manager).

npm install mongodb

• Wait for the installation to complete. Once it's finished, you can start using the driver in your Node.js project.

Step 3: Generate a free Atlas cluster with MongoDB and load the sample

Here are the steps to create a free MongoDB Atlas cluster and load the sample data:

1. Go to the MongoDB Atlas website at https://www.mongodb.com/cloud/atlas and click the "Get started free" button.

2. Sign up for an account by entering your email address and creating a password. If you already have an account, simply log in.

3. Once you're logged in, click the "Create a cluster" button.

4. Choose the "Free" tier for your cluster and select your preferred cloud provider and region.

5. Give your cluster a name and click the "Create Cluster" button. It may take a few minutes for your cluster to be created.

6. Once your cluster is ready, click the "Connect" button next to it and then select "Connect with MongoDB Compass".

7. Follow the instructions to download and install MongoDB Compass, a GUI tool for MongoDB.

8. Open MongoDB Compass and select "Fill in connection fields individually". Enter the connection details for your cluster, including the connection string, username, and password.

9. Click the "Connect" button to connect to your cluster.

10. Once you're connected, click the "Load Sample Data" button to load the sample data into your cluster. This will create a database called "sample_mflix" and a collection called "movies" with sample movie data.

Step 4: Connect Node.js to a MongoDB database

1. After installing MongoDB Node.js Driver, create a new MongoClient object and specify the connection URL for your MongoDB database. You can use a local MongoDB instance or a remote database service like MongoDB Atlas. 

const MongoClient = require('mongodb').MongoClient; const uri = 'mongodb+srv://<username>:<password>@<cluster>.mongodb.net/<database-name>?retryWrites=true&w=majority'; const client = new MongoClient(uri, { useNewUrlParser: true, useUnifiedTopology: true });

Replace <username>, <password>, <cluster>, and <database-name> with your own values. And this is how you must get started with Node.js MongoDB.

2. Connect Node.js to the MongoDB server using the connect() method of the MongoClient object.

client.connect(err => {   if (err) {     console.error('Failed to connect to MongoDB:', err);     return;   }   console.log('Connected successfully to MongoDB'); });

The connect() method takes a callback function that will be called once the connection is established. If an error occurs, the callback will be called with the error as the first argument.

3. Use the client.db() method to get a reference to the database you want to use.

const db = client.db('<database-name>');

Replace <database-name> with the name of your database.

4. Use the db.collection() method to get a reference to the collection you want to work with.

const collection = db.collection('<collection-name>');

Replace <collection-name> with the name of your collection.

5. Perform database operations using the methods of the collection object. For example, you can insert a document into the collection using the insertOne() method:

collection.insertOne({ name: 'John Doe', age: 30 }, (err, result) => {   if (err) {     console.error('Failed to insert document:', err);     return;   }   console.log(`Inserted document with ID ${result.insertedId}`); });

This code will insert a document with the fields name and age into the collection.

6. Close the connection to the MongoDB server using the close() method of the MongoClient object.

client.close();

Here's the complete code example that connects Node.js to a MongoDB database, inserts a document into a collection, and then finds all documents in the collection:

const MongoClient = require('mongodb').MongoClient; const uri = 'mongodb+srv://<username>:<password>@<cluster>.mongodb.net/<database-name>?retryWrites=true&w=majority'; const client = new MongoClient(uri, { useNewUrlParser: true, useUnifiedTopology: true }); client.connect(err => {   if (err) {     console.error('Failed to connect to MongoDB:', err);     return;   }   console.log('Connected successfully to MongoDB');   const db = client.db('<database-name>');   const collection = db.collection('<collection-name>');   collection.insertOne({ name: 'John Doe', age: 30 }, (err, result) => {     if (err) {       console.error('Failed to insert document:', err);       return;     }     console.log(`Inserted document with ID ${result.insertedId}`);     collection.find({}).toArray((err