# docker-letsencrypt-cron
Create and automatically renew website SSL certificates using the letsencrypt free certificate authority, and its client *certbot*.

This image will renew your certificates every 2 months, and place the lastest ones in the /certs folder in the container, and in the ./certs folder on the host.

# Usage

## Setup

In docker-compose.yml, change the environment variables:
- WEBROOT: set this variable to the webroot path if you want to use the webroot plugin. Leave to use the standalone webserver.
- DOMAINS: a space separated list of domains for which you want to generate certificates.
- EMAIL: where you will receive updates from letsencrypt.
- CONCAT: true or false on whether you want to concatenate the certificate's full chain with the private key (required for e.g. haproxy), or keep the two files separate (required for e.g. nginx or apache).

## Running

### Using the automated image

docker run --name certbot -v `pwd`/certs:/certs --restart always -e "DOMAINS=domain1.com domain2.com" -e "EMAIL=webmaster@domain1.com" -e "CONCAT=true" henridwyer/docker-letsencrypt-cron

### Building the image

The easiest way to build the image yourself is to use the provided docker-compose file.

```shell
docker-compose up -d
```

The first time you start it up, you may want to run the certificate generation script immediately:

```shell
docker exec certbot ash -c "/scripts/run_certbot.sh"
```

At 3AM, on the 1st of every odd month, a cron job will start the script, renewing your certificates.

# ACME Validation challenge

To authenticate the certificates, the you need to pass the ACME validation challenge. This requires requests made on port 80 to your.domain.com/.well-known/ to be forwarded to this container.

The recommended way to use this image is to set up your reverse proxy to automatically forward requests for the ACME validation challenges to this container.

## Haproxy example

If you use a haproxy reverse proxy, you can add the following to your configuration file in order to pass the ACME challenge.

``` haproxy
frontend http
  bind *:80
  acl letsencrypt_check path_beg /.well-known

  use_backend certbot if letsencrypt_check

backend certbot
  server certbot certbot:80 maxconn 32
```

## Nginx example

If you use nginx as a reverse proxy, you can add the following to your configuration file in order to pass the ACME challenge.

``` nginx
upstream certbot_upstream{
  server certbot:80;
}

server {
  listen              80;
  location '/.well-known/acme-challenge' {
    default_type "text/plain";
    proxy_pass http://certbot_upstream;
  }
}

```

# More information

Find out more about letsencrypt: https://letsencrypt.org

Certbot github: https://github.com/certbot/certbot

# Changelog

### 0.3
- Add support for webroot mode.
- Run certbot once with all domains.

### 0.2
- Upgraded to use certbot client
- Changed image to use alpine linux

### 0.1
- Initial release