Keep original tag and only append sha256 digest

[nuriel77]

Describe the problem/challenge you have
[A description of the current challenge that you are experiencing.]
Sorry if I have missed this while checking the documentation, but is it possible to maintain the original tag and simply append the digest? The effect would be the same, while keeping the image's original version tag readable.

Describe the solution you'd like
[A clear and concise description of what you want to happen. If applicable a visual representation of the UX (ex: new CLI argument name, the behavior expected).]

For example:
nginx:1.14.2

Would become:

index.docker.io/library/nginx:1.14.2@sha256:f7988fb6c02e0ce69257d9bd9cf37ae20a60f1df7563c3a2a6abe24160306b8d

Anything else you would like to add:
[Additional information that will assist in solving the issue.]

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[joaopapereira]

Hey @nuriel77, thanks for opening up this issue.
To the best of my knowledge, there is no way to keep the tag after we resolve the SHA.

Do you mind explaining to us a little more about your use case for this?

[nuriel77]

@joaopapereira Hi!

Yes, so basically when you keep the tag it is easier to see which version of the image is being used rather than just having the SHA alone.

index.docker.io/library/nginx:1.14.2@sha256:f7988fb6c02e0ce69257d9bd9cf37ae20a60f1df7563c3a2a6abe24160306b8d

This is useful when checking pods and their deployed images to infer the version.

[joostvdg]

What @nuriel77 said.

In addition, there are the following arguments:

• versioning of the application happens via setting Git Tags. I want to correlate the Tag in Git with the Docker Tag
• automated cleanup processes of Tags with specific formats, e.g., x.y.z-rc*

[joaopapereira]

Hey
Sorry for not replying earlier.

Is this something that yll would want to happen by default or only done when a configuration is done?

If we decide to do this by default this might cause issues to people that are currently using kbld because the output YAML would be different between versions(To be fair I do not think this is a huge issue but would like to state it out loud to see what yll think).
At the same time if we decide that this should be configurable we would have to add maybe a new key in the overrides section of the config something like

apiVersion: kbld.k14s.io/v1alpha1
kind: Config
overrides:
- image: nginx:1.2.3
  keepTag: true

What do yll think?

[nuriel77]

Valid concern.
I think that adding the keepTag makes sense when introducing this new change. Maybe somewhere down the road it can become the default.

[joostvdg]

Agreed, looks good enough for me.

[joaopapereira]

Cool, going to accept this feature.
Just to set expectations here, the maintainer team is a little busy with other work which might cause the development of this tool to take some time. Nevertheless, we are more than happy to review contributions or even help with the implementation of the feature.