Rewnew LetsEncrypt Certificate using docker. I use this for a crontab script.

renew-cert.sh

#!/bin/bash

DOMAIN="$1"
TYPE="$2"

if [[ "$DOMAIN" == "" ]]; then
  echo "No domain passed e.g. example.com"
  exit 1
fi

if [[ "$TYPE" == "" ]]; then
  echo "No type passed e.g. digitalocean or cloudflare"
  exit 1
fi

DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null && pwd )"

if [[ "$TYPE" == "digitalocean" ]]; then
  export DIGITALOCEAN_CREDS="${DIR}/do_creds.ini"
  docker run \
    -it --rm --name certbot \
    -v "${DIGITALOCEAN_CREDS}:/root/.secrets/certbot/digitalocean.ini:ro" \
    -v "/etc/letsencrypt:/etc/letsencrypt" \
    -v "/var/lib/letsencrypt:/var/lib/letsencrypt" \
    "certbot/dns-digitalocean" \
      certonly \
        --keep \
        --quiet \
        --preferred-challenges dns-01 \
        --agree-tos \
        --dns-digitalocean \
        --dns-digitalocean-credentials ~/.secrets/certbot/digitalocean.ini \
        -d "$DOMAIN"
elif [[ "$TYPE" == "cloudflare" ]]; then
  export CLOUDFLARE_CREDS="${DIR}/cf_creds.ini"
  docker run \
    -it --rm --name certbot \
    -v "${CLOUDFLARE_CREDS}:/root/.secrets/certbot/cloudflare.ini:ro" \
    -v "/etc/letsencrypt:/etc/letsencrypt" \
    -v "/var/lib/letsencrypt:/var/lib/letsencrypt" \
  certbot/dns-cloudflare \
    certonly \
    --keep \
    --quiet \
    --preferred-challenges dns-01 \
    --agree-tos \
    --dns-cloudflare \
    --dns-cloudflare-credentials ~/.secrets/certbot/cloudflare.ini \
    -d "$DOMAIN"
fi