Get Template Version in Templates?

[rondefreitas]

I can't find the answer here beyond _copier_conf.vcs_ref / _copier_conf.vcs_ref_hash but I'm trying to figure out how to get the version of the template so I can render it out to one of my template output files.

vcs_ref is only populated if the user passes it in at the command line, and the hash would require me to use a script to go back to git to get the name of the tag...

Any help would be appreciated.

[sisp]

I think we could expose the resolved VCS ref instead of the optionally passed value of vcs_ref/--vcs-ref in the render context. Similarly, _copier_conf.src_path isn't the original source URL passed via CLI or API but the local path of the template (clone). As an (I just realized) unintended side effect of #2136, _copier_conf.vcs_ref already refers to the resolved VCS ref when updating with --vcs-ref :current: but not in other scenarios. This is inconsistent for sure. WDYT, @pawamoy, and if you agree, would changing the render context as described be a (breaking) fix or a feature in your opinion? Alternatively, we could partially revert #2136 to expose only the passed vcs_ref/--vcs-ref value in the render context again. Of course, this wouldn't solve the problem in this discussion but restore previous behavior.

[pawamoy]

So IIUC, this would be breaking for users who check _copier_conf.vcs_ref against "" or None? A quick search on GitHub tells me nobody is doing that, and only a single template is actually using _copier_conf.vcs_ref_hash, not even _copier_conf.vcs_ref.

So to me it would make a lot of sense to populate _copier_conf.vcs_ref in all cases, with the following logic maybe:

• if passed explicitly on the CLI, use that value
• otherwise try to use tag if there's one
• otherwise try to use branch name? not sure about this one
• otherwise (last option), use commit sha (same as vcs_ref_hash)

In short it would make vcs_ref the "friendly" reference, and vcs_ref_hash would continue being the commit hash, always.

[sisp]

Sounds good me. Only

• otherwise try to use branch name? not sure about this one

I wouldn't do because branches are typically unstable references. I'll send a PR and mark it as a fix; thanks for the GitHub search, that's a good idea!

[rondefreitas]

Digging through the source, turns out there's an undocumented property _commit that's available in the questions template and can easily be made the default for an answer variable like so, while handling for dirty commits:

source_commit:
    type: str
    when: false
    default: "{% if '-' in _commit %}{{ _copier_conf.vcs_ref_hash }}{% else %}{{ _commit }}{% endif %}"

[rondefreitas]

That said, I really like your suggestion of turning vcs_ref into the friendly reference... that would have prevented me from going down this rabbit hole, and would have represented what I'm already trying to do.

If it helps for context... my template repo has both the template and the main framework python modules for a child project which is fully internal to our org.

The reason I needed this was so I could set the right version constraints of dependencies in updates to subproject's pyproject.toml, based on the tag/version of the main repo and module.

Thanks @pawamoy , @sisp