confd

Take a look at confd, a single statically-linked executable that can expand config file templates using environment variables: https://github.com/kelseyhightower/confd Basically, you add confd into your Docker image and execute it at runtime to do just-in-time config file generation. Here's an example for nginx: https://github.com/grosskur/nginx-confd-dockerfile You can create separate environment variable files for beta/staging/prod and pass --env-file to "docker run". This lets you use the same Docker image across all your environments and avoid the operational complexity of mounting config files in Docker volumes.

Hey that watch stuff is pretty neat, I might have to switch back in some of my containers :-) https://github.com/kelseyhightower/confd/commit/16d6b347c3d3...

Again not to take anything away from consul-template or pyconfd, but confd supports "real-time" updates from both consul and etcd, the watch support was added about 2 weeks ago on the master branch. confd also has dry run support: https://github.com/kelseyhightower/confd/blob/master/docs/no... It was apart of the initial release of confd. These distributed K/V stores are designed to offer a minimal feature set, and the watch support is a perfect way to deliver events to clients. While HTTP call backs would be nice, I think you have to draw the line somewhere. Since these types of systems, consul or etcd, sit at a critical point in the infrastructure lets keep them lean and focused. But that's just my opinion.

Not to take anything away from consul-template, but that has been a feature of confd for a while: https://github.com/kelseyhightower/confd/blob/master/docs/te...

If you're still interested in doing this for any reason, check out confd [0] for populating templates based on etcd values. [0] https://github.com/kelseyhightower/confd

From the same guy that brought us confd: https://github.com/kelseyhightower/confd