podman_image: using force is required to pull locally existing changed image from registry

[cwchristerw]

I think using pull with this module should check from registry if it has newer image or digest has changed, then pull image only when it has changed. I would like to not use force parameter, because it will waste limited quota very fast. In my own registry there is no quota and I can continue to use force: true, but in case of Docker Hub this isn't possible.

I will build my own versions of these images in single machine and then push them to my own Gitea instance.

This might be related to issue in the past #153.

[cwchristerw]

There is no module to get latest image information from repository, which causes this problem to be currently only solvable by using uri module and using HEAD request.

[sshnaidm]

Podman doesn't support such functionality, there is a Skopeo tool for this. I don't think image module should require a Skopeo.
But I'm open to a separate Skopeo module.

[sshnaidm]

related to #876 as well

[cwchristerw]

If its not possible to make it with podman itself then skopeo module would be good solution to make.

[sshnaidm]

Yeah, I'd like to have it. Would you like to prepare a patch 😄 ?

[cwchristerw]

Unfortunately I have no time and original reason why I suggested this wasn't solution to my real problem with Docker Hub quota. Docker Hub requires clients to login when getting digest in HEAD request from images and I'm not aware of what scope should be in login request to get info about all public images with one login request. But in current documentation of Docker Hub API it will have scope of one image and this will consume quota as fast as issuing podman pull directly. I'm not sure if skopeo has solved this quota issue itself somehow, if they have then it could be solution, but currently I have too much work todo before the end of the year.