Docker error message

[bluescarni]

Describe the bug Since a few days, this github action is not working properly for me any more. For reference, I am using the most basic setup as described in the project README - here's my yml file:

https://github.com/bluescarni/heyoka.py/blob/main/.github/workflows/gh_actions_ci.yml#L46

When the action executes after a push to main, it fails with error message:

 IMAGE_NAME must be explicitly set when DOCKER_USERNAME isn't set.

See here for the complete logs:

https://github.com/bluescarni/heyoka.py/runs/3074724754

I did not change anything in my CI configuration files recently.

Expected behavior The action should execute correctly.

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[yuvipanda]

Thank you for reporting this, @bluescarni

@consideRatio do you think this is related to #73?

[yuvipanda]

ok I think https://github.com/jupyterhub/repo2docker-action/pull/73/files#r670389529 is the cause

[consideRatio]

This was intentional from #73 (https://github.com/jupyterhub/repo2docker-action/pull/73#discussion_r665752417). I didn't see this to be documented behavior in any place so it felt reasonable to not set DOCKER_USERNAME to be $GITHUB_ACTOR and then let IMAGE_NAME be set with DOCKER_USERNAME as a fallback.

I don't consider this a bug but rather intentional behavior given the documentation we have. No examples in the docs are broken still right? What is the intentional behavior that is wanted though?

---

UPDATE: wooops well there is a big example, the first example, that use a config like this. So, this is a bug in one way or another.

What is desired, to have the example in the readme updated, or the logic updated to be like before and with all that logic which was quite non-obvious described?

[yuvipanda]

What is desired, to have the example in the readme updated, or the logic updated to be like before and with all that logic which was quite non-obvious described?

I think we should update the logic, since in many NO_PUSH situations you don't care about the image name. Plus this probably breaks a few installations out there.

[bluescarni]

Thanks! I can confirm the action is again working properly on my side.