nginx + Let's encrypt = <3

1_install_lets_encrypt

#!/bin/bash

sudo apt-get install git bc
sudo git clone https://github.com/letsencrypt/letsencrypt /opt/letsencrypt
sudo mkdir /var/www/letsencrypt
sudo chown www-data /var/www/letsencrypt

2_generate_cert

#!bin/bash

sudo service nginx stop
cd /opt/lestencrypt
./letsencrypt-auto certonly --standalone
sudo service nginx start

3_https.vhost

server {
	listen 443 ssl; 
	server_name domain.com;
	ssl_certificate /etc/letsencrypt/live/domain.com/fullchain.pem;
	ssl_certificate_key /etc/letsencrypt/live/domain.com/privkey.pem;
	ssl_protocols TLSv1 TLSv1.1 TLSv1.2;
	ssl_prefer_server_ciphers on;
	ssl_ciphers 'EECDH+AESGCM:EDH+AESGCM:AES256+EECDH:AES256+EDH';
	
	location /.well-known/acme-challenge {
        	root /var/www/letsencrypt;
    	}

	access_log /var/log/nginx/website.log;
	location / {
		proxy_set_header X-Real-IP $remote_addr;
      		proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
      		proxy_set_header Host $http_host;
      		proxy_set_header X-NginX-Proxy true;

      		proxy_pass http://localhost:3000/;
      		proxy_redirect off;      
	}
}
server {
	listen 80;
	server_name domain.com;
	return 301 https://$host$request_uri;
}

4_renew-letsencrypt.ini

# /usr/local/etc/renew-letsencrypt.ini
# All flags used by the client can be configured here. Run Let's Encrypt with
# "--help" to learn more about the available options.

# Use a 4096 bit RSA key instead of 2048
rsa-key-size = 4096

# Uncomment and update to register with the specified e-mail address
email = email@gmail.com

# Uncomment and update to generate certificates for the specified
# domains.
domains = domain.com, www.domain.com, sub.domain.com

# Uncomment to use a text interface instead of ncurses
# text = True

# Uncomment to use the standalone authenticator on port 443
# authenticator = standalone
# standalone-supported-challenges = tls-sni-01

# Uncomment to use the webroot authenticator. Replace webroot-path with the
# path to the public_html / webroot folder being served by your web server.
# authenticator = webroot
webroot-path = /var/www/letsencrypt

5_renew_letsencrypt.sh

#!/bin/bash
# /usr/local/sbin/renew_letsencrypt.sh
# https://gist.githubusercontent.com/thisismitch/e1b603165523df66d5cc/raw/fbffbf358e96110d5566f13677d9bd5f4f65794c/le-renew-webroot

web_service='nginx'
config_file="/usr/local/etc/renew-letsencrypt.ini"

le_path='/opt/letsencrypt'
exp_limit=30;

if [ ! -f $config_file ]; then
        echo "[ERROR] config file does not exist: $config_file"
        exit 1;
fi

domain=`grep "^\s*domains" $config_file | sed "s/^\s*domains\s*=\s*//" | sed 's/(\s*)\|,.*$//'`
cert_file="/etc/letsencrypt/live/$domain/fullchain.pem"

if [ ! -f $cert_file ]; then
	echo "[ERROR] certificate file not found for domain $domain."
fi

exp=$(date -d "`openssl x509 -in $cert_file -text -noout|grep "Not After"|cut -c 25-`" +%s)
datenow=$(date -d "now" +%s)
days_exp=$(echo \( $exp - $datenow \) / 86400 |bc)

echo "Checking expiration date for $domain..."

if [ "$days_exp" -gt "$exp_limit" ] ; then
	echo "The certificate is up to date, no need for renewal : $days_exp days left."
	exit 0;
else
	echo "The certificate for $domain is about to expire soon. Starting webroot renewal script..."
        $le_path/letsencrypt-auto certonly -a webroot --agree-tos --renew-by-default --config $config_file
	echo "Reloading $web_service"
	/usr/sbin/service $web_service restart
	echo "Renewal process finished for domain $domain"
	exit 0;
fi

6_auto_renewal

sudo chmod +x /usr/local/sbin/renew_letsencrypt.sh
sudo crontab -e
# Crontab entry
# 30 2 * * 1 /usr/local/sbin/renew_letsencrypt.sh >> /var/log/renew_letsencrypt.log

7_test_renewal_conf

cd /opt/letsencrypt
./letsencrypt-auto certonly -a webroot --renew-by-default --config /usr/local/etc/renew-letsencrypt.ini
sudo service nginx restart