Deploying Express.js Web Application to VPS with Nginx, PM2 and Ubuntu 16.04/18 or Debian

Prerequisites :

1. CREATING USER

We want to create a new user with “sudo” rights because it’s bad practice to user default

root user in production.

I will create a user with the name algo.

# creating new user
adduser algo

# providing superuser rights
usermod -aG sudo algo

Log out and log in as your new user.

sudo apt-get update && sudo apt-get upgrade

2. Node.js
We will install Node.js version 10

# this command will download install script with curl

curl -o- https://raw.githubusercontent.com/creationix/nvm/v0.33.11/install.sh | bash

# or use wget
wget -qO- https://raw.githubusercontent.com/creationix/nvm/v0.33.11/install.sh | bash

Then log out and log back in.

# check if installed
nvm --version
==> 0.33.11

# list available Node.js versions
nvm ls-remote

# choose one version and install it
# example of v10.4.1 installation
nvm install v10.4.1

# check if installed properly
node --version
==> v10.4.1

NVM is a powerful tool, that allows you to have multiple Node versions installed and to switch between them as you like.

Creating a basic server with Express.js

# go to your user's directory
cd /home/algo

# create folder simpleServer
mkdir simpleServer

# go inside
cd simpleServer

# create package.json
npm init -y

# install Express.js
npm install express

Create a file with this text inside it and save it. You can use nano or any other tool using Nano or VIM

# open nano
nano server.js

# to save, press Ctrl + X ==> Y ==> Enter

# start server
node server.js
==> Listening on http://localhost:3000

If you go to <YourVPSIpAddress>:3000, you should see “Hello World!” inside your browser widow.

If you now close your SSH client widow, your website will stop working. We need some tool that will keep our server “alive”. Say hello to PM2!

# globally install PM2
npm install pm2 -g

# check if installed properly
pm2 -V
==> 2.10.4

PM2 will make our server run in the background and if it crashes, PM2 will restart it automatically.

# start our server with PM2
pm2 start server.js

# check <YourVPSIpAddress>:3000 if your server is running

Make PM2 to start at boot

If we now reboot VPS, our server won’t start up.

pm2 startup
# this will generate another command that you need to run

# We also need to save what processes 
# should get started with pm2
pm2 save

# reboot VPS and check if your website is up
sudo reboot

Install Nginx:

sudo apt-get install nginx

# check if installed
sudo nginx -v
==> nginx version: nginx/1.14.0 (Ubuntu)

Create a configuration file for your server.

cd /etc/nginx/sites-available

sudo nano simpleServer

Inside this file write this piece of code:

server {
    listen 80;
    server_name <YourVPSIpAddress>;

    location / {
        proxy_pass http://localhost:3000/;
    }
}

If you have your domain set up, you can do this.

# ...
server_name www.xyz.com xyz.com;
# ...

Final steps

# check if your configuration is ok

sudo nginx -t

# enable your configuration
sudo ln -s /etc/nginx/sites-available/simpleServer /etc/nginx/sites-enabled

# restart nginx
sudo systemctl restart nginx

Your server should be now available on <Your VPS IP-Address>

This is just a basic setup to get you running as soon as possible. For production it’s probably a good idea to do some other things: