There's some delicate ownership issues with the files mounted into the containers that need to be addressed in documentation for Docker Compose and Nomad. The issue is exactly the same for both of them so @lordy2 has promised to document what they had to do and I'll make sure it's universally applicable.
docs/docker.rst now has a bit more info in it, including a real example of creating a data dir and chowning it to www-data:www-data. In theory that should be enough.
There's some delicate ownership issues with the files mounted into the containers that need to be addressed in documentation for Docker Compose and Nomad. The issue is exactly the same for both of them so @lordy2 has promised to document what they had to do and I'll make sure it's universally applicable.