Re: [atomic-devel] dependencies for spc containers on atomic hosts

If so, is there some
"atomic" provider that installs all containers that a nulecule specifies?

Check out Atomicapp https://github.com/projectatomic/atomicapp

Nulecule is the specification for handling multi-container multi-provider applications. Atomicapp is a reference implementation that consists of a tool that can deploy Nulecule defined apps. There is an Atomicapp container that can be used as a base layer with atomic that uses docker LABELs to provide run instructions. I've not tried a SPC container with an Atomicapp.

cc'ing container-tools list to get some visibility to the Nulecule/Atomicapp folks.

- Matt M

On Mon, Aug 24, 2015 at 9:37 AM, Colin Walters <walters verbum org> wrote:

On Fri, Aug 21, 2015, at 09:07 AM, Tobias Florek wrote:
> Hi,
>
> is there a way to specify dependencies for (spc) containers that provide
> some service?

This is an interesting topic; both raw docker and kubernetes lack
dependency mechanisms. I think down the line, kubernetes is going
to have to grow this to some degree. Currently one can basically just
do retry/backoff loops in applications.

> Is nulecule the way to do it? If so, is there some
> "atomic" provider that installs all containers that a nulecule specifies?

We don't have a best practice around this yet that I'm aware of, but I would
approach it with systemd units whose ExecStart=docker run. (Or if you want
in the future, drop to runc, or use systemd-nspawn)

I think you could indeed use nulecule to handle pulling multiple images
and generating unit files to install them.