stable tag for containers

[garryod]

During development of services it would be nice if we could have a stable tag for containers which would be applied to non alpha/beta/dev releases, allowing latest to point to potentially unstable releases

[coretl]

I'd prefer to detect pre-release tags (alpha/beta/dev), release them, but not point latest at them. Is this possible with the docker action?

[garryod]

That seems reasonable, could we point nightly or something similar at them instead? And yeah, just need to add a bit of logic to the tags section of docker/metadata-action

[coretl]

We already do something similar for github releases, could extract this somewhere:

python3-pip-skeleton/.github/workflows/code.yml

Line 194 in db76a31

prerelease: ${{ contains(github.ref_name, 'a') || contains(github.ref_name, 'b') || contains(github.ref_name, 'rc') }}

[gilesknap]

I can see a nice way to implement this using the same condition as prerelease.

Will make a PR.

[gilesknap]

do we want
stable: for non alpha/beta
nightly: for alpha/beta

and no latest?

[coretl]

I would prefer latest pointing to latest non-prerelease version, and requiring people to point at a specific pre-release version. @garryod would this suit you?

[gilesknap]

I like that - and it matches what for example python does on dockerhub https://hub.docker.com/_/python/tags

[garryod]

I would prefer a nightly or equivalent, but I can work with pointing to specific versions

[gilesknap]

I've said I'd make a PR but I see this is assigned to you Garry - and I see you know about the enable flag for https://github.com/docker/metadata-action tags.

[coretl]

I don't mind who does this. Who would like to make the PR?

[garryod]

Went ahead and tried this and found some weirdness due to latest being applied by default. It seems that anything but latest is suggested for moving tags, see: https://vsupalov.com/docker-latest-tag/