https://github.com/qdm12/omada has a docker-compose.yml file in 3.0 format, but I run it on Ubuntu 16.04 (docker-compose 1.8.0-2) which only accepts a 2.0 format. Here's my docker-compose.yml in case it saves anyone with old Linux some time.
The dockrun script is if one wants to start the docker by hand.