acme.sh server script

#!/bin/bash
admin="<email>"
site="<the site we need a cert for>"
dest="/etc/nginx/certs"
remote_file="https://acme.int.<domain>/$site/fullchain.cer"
local_file="$dest/$site-fullchain.cer"

# create local file if it doesnt exist
[ -f $local_file ] || touch -t 8001031305 $local_file

# get the potential new cert
modified=$(curl --silent --head $remote_file | \
    awk '/^Last-Modified/{print $0}' | \
    sed 's/^Last-Modified: //')
remote_ctime=$(date --date="$modified" +%s)
local_ctime=$(stat -c %Y "$local_file")

if [ $local_ctime -lt $remote_ctime ] ; then
    curl -Ls  https://acme.int.flattr.net/$site/fullchain.cer -o $dest/$site-fullchain.cer
    curl -Ls  https://acme.int.flattr.net/$site/$site.key -o $dest/$site-fullchain.key
    nginx -t > /dev/null 2>&1
    #reload nginx if success
    [ $? -eq 0 ] && service nginx reload ||  echo "error updating $site with le-acme" | mail -s "Error doing letsencrypt on $site" "$admin"
fi