Docker Support

As far as I can tell, /v2/<name/ is the same as the /v1/<namespace>/<repository>. In the case that there is no namespace, Docker hub still hosts the content at library/<repository>, so I am assuming that <name> = <namespace>/<repository>

Neither will correctly work at the moment due to the auth bug, but on the branch that is fixing that:

This will sync correctly:

pulp-admin docker repo create --repo-id=busybox --feed=https://registry-1.docker.io --upstream-name=library/busybox

This will not sync correctly:

pulp-admin docker repo create --repo-id=busybox --feed=https://registry-1.docker.io --upstream-name=busybox

To fix this, we have some options.

1. upstream-name could be required to have a namespace. I this is not ideal, since docker itself doesn't require this and assumes library/<repo> if a namespace is not provided.
2. We can prepend "library/" to self.name here: https://github.com/pulp/pulp_docker/blob/master/plugins/pulp_docker/plugins/registry.py#L290 This would be my preference, but I am unsure if this would have unintended consequences elsewhere. Specifically I am curious why for v1 this is only done in the `get_tags` function. This works with the busybox repo example above.
3. We could prepend "library/" where it is needed. At least get_tags.

So, for Docker Hub, adding "library" will work because Docker Hub is special.

For other Distribution instances, or other implementations, adding "library" will not work. "busybox" and "library/busybox" reference different repositories, except as a special case on Docker Hub.

That's what this bug is about: when syncing from a V2 registry, "library" is always added and that is incorrect.

To be clear: correct behaviour would be for pulp_docker to be requesting /v2/busybox/ when upstream-name is busybox. The current incorrect behaviour is that it requests /v2/library/busybox/.

See also https://github.com/openshift/origin/issues/6570, where a similar bug was also fixed.

Pulp wrote:

Reopening due to https://pulp.plan.io/issues/1685.

We probably need to adjust the code that fixed this originally.

Good catch Austin, I would have forgotten about this!

--
Randy Barlow
irc: bowlofeggs

There was some behavior change at the dockerhub endpoints, but it turns out that we do not need to change anything on our end as far as namespacing the repos goes.