docker-flow-proxy-letsencrypt is a docker-flow-proxy companion that automatically create and renew certificates for your swarm services using letsencrypt.

Join the #df-letsencrypt Slack channel in DevOps20 and ping me (@nibor) if you have any questions, suggestions, or problems.

The mecanism is mostly inspired by the JrCs/docker-letsencrypt-nginx-proxy-companion designed for jwilder/nginx-proxy.

Normally (without using DFPLE) when a new service is created in the swarm, the docker-flow-swarm-listener (DFSL) will send a notify request to the docker-flow-proxy (DFP) wich reload based on new config.

DFSL  -----notify----->  DFP

docker-flow-proxy-letsencrypt (DFPLE) acts as a man-in-the-middle service which gets notify requests from DFSL, process its work, and then forward original request to DFP.

DFSL  -----notify----->  DFPLE  -----notify----->  DFP

Its work consists in :

• check if letsencrypt support is enabled by the service (check service labels)
• generate or renew certificates using certbot utility (if support enabled)
• distribute certificates to DFP (if support enabled)
• forward request to dfp

Check the tutorial to get started with docker-flow-proxy-letsencrypt environment.

Please note that in order to keep persistent certificates :

• on DFPLE side : you will need to use a volume on /etc/letsencrypt,
• on DFP side : you will have to either use a volume (see example using volumes) or store certificates as secrets (see example using secrets)

You can use both dns and http letsencrypt ACME challenges (see configuration).

Automatic renewal is performed at fixed interval. By default renewal process is performed once per day at 2.30 am. You can specify your own interval using LETSENCRYPT_RENEWAL_CRON env var on DFLE (see configuration).