# Deploy Node.js Application to DigitalOcean

> This step by step tutorial will show you how to set up a Node.js server with MongoDB to DigitalOcean using PM2, NGINX as reverse proxy and a SSL from LetsEncrypt. We will also add a custom domain name.

## Prerequisites
* Download [PuTTY & PuTTYgen](https://www.chiark.greenend.org.uk/~sgtatham/putty/latest.html)
* Download [WinSCP](https://winscp.net/eng/download.php)

## Create Droplet & Generate SSH Key
1. Create New Project/Create New Droplet
2. Choose Ubuntu, Choose your desired plan & country
3. Click on New SSH Key
4. Open PuTTyGen and generate a new RSA Key
5. Copy the key in the input field and add it to your droplet, **Add SSH Key**
7. **IMPORTANT** Be sure to save the public key as **.txt** and your private key as **.ppk** on your computer, you will need these later
8. **Create Droplet**

## Configure PuTTY
1. Open PuTTY
2. Add your droplets IP Adress to **'Host Name (or IP Adress)'**
3. In Connection -> Data, set username to "root"
4. In SSH -> Auth, load your **privatekey.ppk** that you created from last step
5. Set a session name and SAVE

## Create New User
1. Login to your server, click **yes** if first time connecting to server

2. Add user and assign him to the sudo group: 
```
adduser [username]
usermod -aG sudo [username]
```
You can check to make sure that user was added in sudo group ``id [username]``


3. Login as that user:</br>
```
sudo su - [username]
```

## Authorize Key For New User
1. Make new directory:
```
mkdir ~/.ssh
```

2. Change permission:
```
chmod 700 ~/.ssh
```

3. Create and go into new file:
```
nano ~/.ssh/authorized_keys
```

4. Copy ssh key from **publickey.txt** (exclude "Comment: rsa-key-date")
   Inside **authorized_keys** on the first line type: "ssh-rsa" space and add your key, also make everything in one line.
   > It should look something like this now: “ssh-rsa AAAABaxASDVAV17547DFDVGDVG...”</br>
   
   Save file: Ctrl+X & Y

5. Set permission for that file:
```
chmod 600 ~/.ssh/authorized_keys
```

6. Restart service:
```
sudo service ssh restart
```

7. Exit terminal and login as new user. Load config, click **Data** and change root to your [username].

## Disable Root & Password Login AND Change SSH-port
#### Disable Root & Password Login
1. Go into ssh config file:
```
sudo nano /etc/ssh/sshd_config
```
2. Search for PermitRootLogin: **Ctrl+W** and type "PermitRootLogin"
3. Set PermitRootLogin to "no"
4. Search for PasswordAuthentication: **Ctrl+W** and type "PasswordAuthentication"
5. Set PasswordAuthentication to "no"

#### Change SSH-port
> A lot of attacks on web servers occur by scripts trying to get into the default port for SSH, port 22. Therefore, we change this, feel free to take a five-digit port (difficulty guessing), but not higher than 65535. (Also: Note the number should not start with 0.)

6. Find the row Port 22 and change it to another port, eg. XXXXX  
**Important: Make sure to remember the Port you changed to**
```
# If the row start with a '#' you should remove it
# Ex.
Port 25565
```
Exit with Ctrl+X and Save
7. Reboot session:
```
reboot
```
8. Close terminal and open PuTTY
9. Now in the port input, type in your new port
> Note that if you try to open the terminal with another port like 22 you will get a "connection refused error".
10. Save and open terminal

## Enable Firewall
> Note: to enable firewall you need to be on the root user. Type ```sudo -i``` or ```sudo -s``` to switch to the root user</br>
> Type ```su - [username]``` to switch back to your user after enabling firewall
1. Enable firewall, ssh, http & https:
```
ufw enable
ufw allow ssh
ufw allow http
ufw allow https
```
To check your firewall status: ```ufw status```

## Install packages
1. Update packages:
```
sudo apt update
```
2. Install latest version of nodejs:
> Note: this is version 14 we are installing, check nodejs homepage and see if there is a newer version, pick the one that says recommended for most users, and change "14" in this command to the new version
```
curl -sL https://deb.nodesource.com/setup_14.x | sudo -E bash -
```
3. Install nodejs & npm:
```
sudo apt-get install nodejs
```
You can make sure they are installed: ```"npm -v" and "node -v"```

## Install PM2
1. Install pm2 globally:
```
sudo npm install -g pm2
```
2. Start server:
```pm2 start index.js``` or ```pm2 start npm -- start```
3. App should now be running on the droplets ip adress:</br> 
> ex.165.227.216.5:8080

## NGINX
1. Install nginx:
```
sudo apt install nginx
```
2. Go into default folder:
```
sudo nano /etc/nginx/sites-available/default
```
3. Remove everything inside the location brackets and add proxies:
```
location / {
	
	proxy_pass http://localhost:8080; #whatever port your app runs on.
	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;
	
}
```
> Note: if localhost does not work use ip address from your droplet.
4. Above the location we have **server_name_;**. Set the server name to your domain name if you want to use a domain name for this app. It should look like this ```server_name mywebsite.com www.mywebsite.com```
5. Exit and save: Ctrl+X & Y
6. Check so nginx is configured properly ```sudo nginx -t```. It should say something like the test is successful
7. Now restart the service ```sudo service nginx restart```

## Clone App from github
> If your project is not on github, upload it to github so we can clone it to your droplet
1. Create ssh key for github:
```
ssh-keygen -t rsa -C 'your@githubemail.com'
```
2. Open **WinSCP** and choose import droplet & login
3. In /home/[username]/ add .ssh because its hidden by default, so go into the /home/[username]/.ssh directory
4. Drag over the **id_rsa.pub** file to the **document** folder and open the file
5. Copy the key and add it to ssh in GitHub
6. Now in your droplets terminal clone the project from github:
```
git clone git@github.com:user/your/repository
```
8. type ```ls``` and boom your project is there
9. ```cd``` into your projext and type ```npm install``` to install all packages that your project contains

## Add domain
1. First buy your domain through preferred service: ex, namecheap, godaddy.
2. Then in DigitalOcean go to the networking tab and add your domain
3. Where it says **HOSTNAME** you will add a "@" and at **WILL DIRECT TO** you want to put your droplet
4. Click on **Create Record**.
> The record you are creating is **"A"**
5. Create a Record for the **www** version, so do the same but replace "@" with "www"
6. Go to your domain name provider. Click on your domain or click manage domain and go to nameservers and click **Custom DNS**
7. Add 3 nameservers. It should look like this:
   * ns1.digitalocean.com
   * ns2.digitalocean.com
   * ns3.digitalocean.com
8. Click save
> Note: it can take up to a couple of hours for the domain name to take effect, but usually it takes 5-15 minutes

## Add SSL with LetsEncrypt (enables HTTPS)
> Note: certbot is deprecated. So its best to install snapshot of certbot so it stays up to date. We will install certbot by following [these instructions](https://certbot.eff.org/lets-encrypt/ubuntubionic-nginx)
> This installation is for web server on Nginx with Ubuntu 20.04
1. Make sure everything is up to date ```sudo apt-get update```
2. You should already have snapd installed, so make sure its up to date with this command:
```
sudo snap install core; sudo snap refresh core
```
3. Before installing certbot, remove it so we can install certbot snap, we dont want them to collide:
```
sudo apt-get remove certbot
```
4. Now install certbot:
```
sudo snap install --classic certbot
```
5. Prepare cerbot with your domains, it should look like this:
```
sudo certbot --nginx -d mywebsite.com -d www.mywebsite.com
```
This command gives you a certificate & Certbot edits your Nginx configuration automatically to serve it, turning on HTTPS access in a single step
6. Almost done, but this certificate will expire in 90 days, to renew it after every 90 days type this command:
```
sudo certbot renew --dry-run
```
# Congratulations you are done! Happy Hacking :D