[feature] Implement registry-to-registry synchronization for products and other artifacts.

[wstutt]

Is this Feature/Enhancement related to an Existing Problem? If so, please describe:

I would like to see the ability to synchronize from one registry to another with both the product flag and just a full skopeo-esque copy from one registry to another

Describe Proposed Solution(s):

Something similar to this:

hauler registry sync --product rancher=v2.13.4 registry://harbor.org.local
^one stop sync from carbide to a private registry.

hauler registry sync registry://registry.source.local registry://registry.dest.local
^sync from one registry to another.

Additional Context:

I had an existing hauler store serving a registry, and I thought it would be extremely convenient to then use a hauler command to populate a private registry.

[HoustonDad]

+100, this would be amazing

[amartin120]

@wstutt Just thinking this through some.

hauler registry sync --product rancher=v2.13.4 registry://harbor.org.local - seems pretty straightforward as the hauler manifest from the products flag will provide a specific list of artifacts. One gotcha here could be if any of the hauler manifests include stuff that's not in a registry. aka... files that are just URLs and helm charts that aren't OCI based... since we would be skipping the part where they would be pulled into haulers store first and "OCI'ified", it wouldn't be an apples to apples comparison.

hauler registry sync registry://registry.source.local registry://registry.dest.local - doable ONLY if the source registry has an exposed API for querying the available artifacts/tags. Otherwise, Hauler wouldn't know what to sync. i.e. AWS ECR probably wouldn't work as a source registry. Also if your destination registry is Harbor, you'd have to know ahead of time all of the "projects" you'd have to create in advance, etc. So this particular option in general will be pretty niche I feel.

None of this to say "no". I just want to work through these thoughts some.

[zackbradys]

I think a proof of concept and initial starting point for this would be with single artifacts aka replacing the workflow of docker pull, docker tag, docker push... with hauler store sync ... ...

And then we could build off of that for full syncs of entire registries or entire --products or whatever else...