Add Github Registry to the supported list

[marc-x-andre]

Github as is own package registry, docker.pkg.github.com, that can be used as a docker registry.

Connecting as a Generic Docker Registry result to 404 page not found error. Maybe the API is different.

More info about Github packages

It could be nice to add Github registry to the list of providers.

[philliphoff]

@the224 It appears that the Github Package Docker Registry does not support the _catalog API used to list the repositories within the registry. I can't find any information about the extent to which Github supports the (V2) API for Docker registries. It does appear to support, for example, listing tags for a given image.

@Phanatic Would you be able to point me to information about Github's support for the Docker registry API?

[Phanatic]

@philliphoff we don't support the _catalog endpoint in the GitHub Docker Registry today.
I can open an issue to track this, which other API endpoints are necessary for this extension to work?
I can check and create issues for any missing support from the Docker HTTP API spec

[philliphoff]

@Phanatic Our extension creates a tree view for Docker registries, listing each repository in a registry and then each tag within a repository, which means supporting at least the _catalog and <repo>/tag/list endpoints. It then allows the user to pull/delete an entire repository, or to pull/untag/delete/get-digest-for individual images. Some of those commands go through the Docker command line, while others use the HTTP API directly (via a Node.js client library), so it's somewhat tedious to identify the exhaustive list of endpoints used, but the closer GitHub can get to 100% coverage of the (V2) spec, the more likely the tools will "just work".

[dbreshears]

@Phanatic, is there an issue logged that we can track and any current status / eta on this? This is a frequent request for a Docker extension container registry feature

[bwateratmsft]

@Phanatic Do you know where we can create/track issues on the API?

[bwateratmsft]

For now I'll resolve this as a dupe of #869, we are tracking GitHub support there.

[jayarjo]

Everybody involved in this, please proceed. @Phanatic please cooperate.