I've got a use case. ACI support would let me use containers without being coupled to Docker's registry. I really don't want to run that software, and I really, really don't want to rely on Docker Hub. ACI's use of existing standards for their "registry" implementation is a major draw for me.
To clarify, I don't want to run my own registry and I don't want to rely on any third party for image hosting. I just want to pull tarballs from a dumb file server. No need to run a registry for that, and no one company has a privileged position in the namespace.
It's maddening, because I love Docker-the-concept but not Docker-the-implementation nor Docker-the-ecosystem. I honestly do understand how many would find the UX of "Docker, Inc. at the center of things" to be a refreshing convenience, but to me that notion is frustrating and repellent, as much so as if Git remotes defaulted to GitHub.
> I just want to pull tarballs from a dumb file server.
Is there something I'm missing that you couldn't just use wget? If you have the URIs, I can't imagine how pulling down an image by name would be more than a quarter-page Python script, even if you include the untarring and such.
Yeah, that's about what I've been doing, but AFAICT I lose the benefits of layering when I refuse to speak the registry protocol. Docker's export command dumps the entire image tree, so I'm stuck transferring GB-sized payloads to deploy the tiniest change to my app. appc manages to do layers without a coordinating registry. (Kind of funny that CoreOS bought Quay, on that note.)
Yes, you can run your own registry, but doing so without every pulling anything from DockerHub means rebuilding all images yourself and tagging all of them for your own registry and pushing to that, or DNS / firewall hacks to redirect requests for index.docker.io (or forking Docker).
