PEP 804: An external dependency registry and name mapping mechanism

[tobiasdiez]

@jaimergp

A hook hasn’t come up yet. What we have discussed is that CLI should allow users the “default” mapping in some way (configuration file, CLI flag, environment variable), which would work as a complete replacement. What you are describing is a mechanism to perform an operation like mapping = deep_update(default_mapping, user_override), correct? I feel that this is up to CLI tools to implement, but maybe we could leave a hint that such feature may be desirable?

Yes, my idea was a mechanism to partially overwrite/fine-tune a given resolution. What I vaguely had in mind was a hook

(depurl, central registry resolution, target system) → custom user resolution (if needed)

But I guess the details don’t matter much at this stage.

At least from my experience I would expect you need such a hook as soon as your package has sufficiently complex dependencies and you would like to have a reproducible env that works “all” the time (eg to install the necessary system deps in cibuildwheels).

I think it would also provide a quite flexible solution to some of the issues discussed in the other PEP thread, like PEP 725: Specifying external dependencies in pyproject.toml (round 2) - #35 by ncoghlan .