VPS Next.js App Deployment Guide

This guide explains how to deploy a Next.js app on a VPS running Ubuntu Server, using PM2, Nginx, and GitHub Actions for continuous deployment. SSL is handled by Certbot, and Fail2Ban with Nginx rate limiting is used for basic security.

1. Provision a VPS and Set Up SSH Access

Get a VPS: Purchase a VPS running Ubuntu Server from your preferred cloud provider.
Connect via SSH: Open a terminal and connect to your VPS.
```
ssh username@your-vps-ip
```

2. Install Node.js via NVM

Install NVM (Node Version Manager):

curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.39.3/install.sh | bash
source ~/.bashrc
nvm install --lts

Verify installation:
```
node -v
```

3. Install PM2

Install PM2:
```
npm install pm2@latest -g
```
Verify PM2 installation:
```
pm2 -v
```

4. Clone Your Next.js Application

Create a directory for your app:
```
mkdir ~/my-app
cd ~/my-app
```

Clone your repository:

git clone https://github.com/your-username/your-repo.git .

5. Install Dependencies

Install your application dependencies:
```
npm install
```

6. Run Your Application with PM2

Start your Next.js app using PM2:
```
pm2 start npm --name "my-app" -- start
```
Save the PM2 process:
```
pm2 save
```
Configure PM2 to start on server boot:
```
pm2 startup
```

7. Configure Nginx as a Reverse Proxy

Install Nginx:
```
sudo apt update
sudo apt install nginx
```
Configure Nginx to point to your Node.js app:
```
sudo nano /etc/nginx/sites-available/my-app
```

Add the following Nginx configuration:

server {
    listen 80;
    server_name my-app.example.com;

    location / {
        proxy_pass http://localhost:3000;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection 'upgrade';
        proxy_set_header Host $host;
        proxy_cache_bypass $http_upgrade;
    }
}

Enable the configuration:

sudo ln -s /etc/nginx/sites-available/my-app /etc/nginx/sites-enabled/

Test and reload Nginx:

sudo nginx -t
sudo systemctl reload nginx

8. Update DNS to Point to Your VPS

Go to your DNS/domain provider and set up an A record pointing my-app.example.com to your VPS's public IP.

9. Install and Configure Certbot for SSL

Install Certbot:

sudo apt install certbot python3-certbot-nginx

Generate SSL certificate:

sudo certbot --nginx -d my-app.example.com

Enable auto-renewal:
```
sudo systemctl enable certbot.timer
```

10. Harden Security with Fail2Ban and Nginx Rate Limiting

Install Fail2Ban:
```
sudo apt install fail2ban
```
Configure Nginx rate limiting by adding these lines to /etc/nginx/nginx.conf:
```
limit_req_zone $binary_remote_addr zone=one:10m rate=10r/s;
```

Apply rate limiting to your app:

location / {
    limit_req zone=one burst=5;
    proxy_pass http://localhost:3000;
}

Restart Nginx:
```
sudo systemctl restart nginx
```

11. Automate Deployment with a Bash Script

Create a deploy.sh script for building and restarting your app.

#!/bin/bash
cd /path/to/your/app
git pull origin main
npm run build
rm -rf .next && mv .next_temp .next
pm2 restart my-app

Make the script executable:
```
chmod +x deploy.sh
```

12. Set Up a Basic Node.js App for Webhooks

Create a simple Node.js webhook listener:

const express = require('express');
const { exec } = require('child_process');
const app = express();
app.use(express.json());

const SECRET = 'your-secret-token';

app.post('/webhook', (req, res) => {
    const token = req.headers['x-secret'];
    if (token === SECRET) {
        exec('./deploy.sh', (err, stdout, stderr) => {
            if (err) return res.status(500).send('Deployment failed.');
            res.status(200).send('Deployment successful.');
        });
    } else {
        res.status(401).send('Unauthorized');
    }
});

app.listen(4000, () => console.log('Webhook listener running on port 4000'));

Start the app with PM2:

pm2 start node webhook.js --name "webhook"

13. Automate Deployment with GitHub Actions

Add a GitHub Actions workflow under .github/workflows/deploy.yml:

name: Deploy to VPS

on:
  push:
    branches:
      - main

jobs:
  deploy:
    runs-on: ubuntu-latest

    steps:
      - name: Checkout code
        uses: actions/checkout@v2

      - name: Trigger deployment webhook
        run: |
          curl -X POST https://my-app.example.com/webhook             -H "x-secret: your-secret-token"

AtharvaCM/VPS_Node_App_Deployment_Guide.md