From Code to the Cloud: A Step-by-Step Guide to Deploying Your Node.js App on AWS EC2

Introduction

In this article, we will deploy a nodejs express app to ec2. We will also add SSL and Nginx in the next article.

Let's dive in

Prerequisites

🎯 AWS account
🎯 Github account
🎯 Nodejs installed on your local machine
🎯 Git installed on your local machine
🎯 Basic knowledge of nodejs and express
🎯 Basic knowledge of git
🎯 Basic knowledge of ssh
🎯 Basic knowledge of linux commands

⏭️ Create a Nodejs express app

Run the following commands in your terminal

mkdir ec2
cd ec2
npm init -y

The -y flag is to skip the questions and use the default values

⏭️ Install the following packages

npm install express dotenv

✅ Express is a web framework for nodejs
✅ Dotenv is a zero-dependency module that loads environment variables from a .env file into process.env.

⏭️ Confirm the installed packages in the package.json file

✅ package.json is the heart💖 of npm. It holds metadata relevant to the project and it is used to give information to npm that allows it to identify the project as well as handle the project's dependencies.

{
  "name": "ec2",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "dependencies": {
    "dotenv": "^16.3.1",
    "express": "^4.18.2"
  }
}

⏭️ Write your start script

In essence, you can run npm start to start your server.

⏭️ Create a .env file

This is where we will store our environment variables. The environment variables are accessible through process.env object. We will use the dotenv package to load the environment variables from the .env file into process.env object.

touch .env

⏭️ Add the following to the .env file

PORT=2323

⏭️ Create a .gitignore file

This is where we will add the files we don't want to push to github. Preventing the .env file from being pushed to github is very important because it contains sensitive information like your database credentials, api keys, etc.

touch .gitignore

⏭️ Add the following to the .gitignore file

node_modules
.env

⏭️ Create app.js

require('dotenv').config(); // load environment variables from .env file
const express = require('express');
const app = express();
const port = process.env.PORT || 3000; // default port is 3000

app.get('/', (req, res) => {
    return res.status(200).json({
        message: 'Hello World'
    });
});

app.listen(port, () => {
    console.log(`Server running on port ${port}`);
});

⏭️ Start the server

Open your terminal and run the following command

npm start

⏭️ Curl the server

Open another terminal and run the following command

curl localhost:2323

You should see the following

⏭️ Create a git repository

Now that we have our app running, let's create a git repository and push our code to github. Run the following commands in your terminal

git init
git add .
git commit -m "Initial commit"

⏭️ Create a new repository on github

⏭️ I choose private because I don't want this code to be public

⏭️ Copy the code in the highlighted area and add to your terminal

⏭️ You should see the following

⏭️ Now lets setup our ec2 instance

Login to your aws account and go to ec2

⏭️ Choose EC2 from the list of services

⏭️ Choose Launch Instance

⏭️ Choose Ubuntu Server 20.04 LTS (HVM), SSD Volume Type

Name your instance and click next

⏭️ Create a new key pair

A key pair consists of a public key that AWS stores and a private key file that you store. Together, they allow you to connect to your instance securely.
⚠️ Ensure you note the location of the key pair

⏭️ Network setting

Tick the the three boxes and click next

• Allow ssh traffic: This allows you to connect to the instance using ssh
• Allow http traffic from internet: This allows you to access the instance from the browser over http (unsecure)
• Allow https traffic from internet: This allows you to access the instance from the browser over https (secure)

⏭️ Review and launch

⏭️ Success

We have successfully created our ec2 instance. Click on the instance highlighted in green to view the details

⏭️ Click on the instance Id to view the details

⏭️ Connecting to the ec2 instance using ssh

There are two ways to connect to the ec2 instance using ssh. You can either use the browser or use the terminal.

Method 1: Using the browser
Click on connect and follow the instructions

⏭️ Click the connect button

⏭️ Change to root user

• Sudo: Super User Do; allows a user with proper permissions to execute a command as another user, such as the superuser.

• su: Switch User; allows you to switch to another user account without logging out of your current terminal session.

• the - flag is used to preserve the environment variables
  

⏭️ Install nvm

nvm is a version manager for nodejs. It allows you to install multiple versions of nodejs and switch between them easily.

curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.34.0/install.sh | bash

⏭️ Activate nvm

We need to activate nvm so that we can use it in the current terminal session

. ~/.nvm/nvm.sh

Install node

Install the latest version of node using nvm

nvm install node

⏭️ Install git

Git is need to clone the repo we created earlier

sudo apt-get update -y
sudo apt-get install git -y

⚠️ You can omit the sudo since you are already root. So just run

apt-get update -y
apt-get install git -y

⏭️ Check if node is installed

We have the latest version of node installed

node -v

⏭️ Check if git is installed

git --version

⏭️ Clone the repo we created earlier using ssh

git clone git@github.com:drsimplegraffiti/ec2-deploy.git

You should get this error because you have not added your ssh key to github

⏭️ Connect github ssh key to ec2 instance

Generate a fingerprint for the ssh key

ssh-keygen -t ed25519 -C "your email"

Click enter thrice and leave the passphrase empty as default. You can add a passphrase if you want to add an extra layer of security.

⏭️ eval the ssh-agent

eval is used to evaluate the ssh-agent in the current terminal session. The ssh-agent is a program that runs in the background and stores your ssh keys. The ssh-agent is used to authenticate you to the remote server without having to type your password every time.

eval "$(ssh-agent -s)"

⏭️ Add the ssh key to the ssh-agent

⏭️ Copy the ssh key to the clipboard

cat ~/.ssh/id_ed25519.pub

⏭️ Paste the ssh key to github

Go to github settings -> SSH and GPG keys -> New SSH key
Paste the key and save. Auhenticate with your github password or Github mobile app

⏭️ Test the connection

Scan the ssh

ssh-keyscan github.com >> ~/.ssh/known_hosts

Let's test the connection to github in the ec2 instance terminal

ssh -T git@github.com

⏭️ Clone the repo again

This time, we should be able to clone the repo without any error

git clone git@github.com:drsimplegraffiti/ec2-deploy.git

⏭️ List the files in the directory

ls -la

You should see the ec2-deploy folder

cd into the ec2-deploy

• cd - change directory

⏭️ See the files in the ec2-deploy folder

ls -la

⏭️ Install dependencies

cd ec2-deploy
npm install

⏭️ Start the server

npm start

We got port 3000 because we ignored the .env file in the .gitignore file

💡 You can also use pm2 to start the server if you want to keep the server running even after you close the terminal
Install pm2 globally

npm install pm2 -g

⏭️ Start the server with pm2

pm2 start app.js

⏭️ Pick the ip address of the ec2 instance and curl it

YAAY! We have our server running on ec2 mapped to this ip address 🎉🎉🎉. However it is not secure because it is running on http. We will add SSL and Nginx in the next article.

⏭️ Method 2: Connecting to the ec2 instance using ssh from your local machine

Click connect from your instance -> connect -> ssh client -> copy the ssh command

⏭️ Open your terminal and cd into the directory where you saved the key pair

cd Downloads

Run the ssh command

ssh -i "devtokey.pem" ubuntu@ec2-35-175-174-169.compute-1.amazonaws.com

⏭️ You will get this warning

This warning is related to permissions. We need to change the permissions of the key pair. We will do that in the next step

⏭️ Chmod the key pair

Chmod is a command in Linux and other Unix-like operating systems that allows to change the permissions (or access mode) of a file or directory.

chmod 400 devtokey.pem

⚙️ 400 - read only by owner
⚙️ 600 - read and write by owner

⏭️ Run the ssh command again

ssh -i "devtokey.pem" ubuntu@ec2-35-175-174-169.compute-1.amazonaws.com

⏭️ You should see the following

⏭️ Start the server

cd ec2-deploy
pm2 start app.js

You should get script already running because we already started the server on the ec2 instance earlier in the browser. Stop the ec2 on the browser by running

pm2 stop app.js

or

pm2 stop 0 # 0 is the id of the script referencing app.js

⏭️ Start the server again

pm2 start app.js

⏭️ Check the ec2 ip by running

curl ifconfig.me

⏭️ Pick the ip address of the ec2 instance and curl it

⏭️ Open another terminal and curl the ip address

curl 35.175.174.169

🎉🎉🎉 We have connected to our ec2 instance using ssh from our local machine.

Conclusion

We have successfully deployed our nodejs express app to ec2. We will add SSL and Nginx in the next article. Thanks for reading. Please leave a comment if you have any questions or suggestions.