[woodruffw]

The issue does not require coordination; that's the point. It's a behavioral aspect of `pip` that's completely opaque to PyPI, because all PyPI does is serve index responses to installers. It doesn't know how many indices the installer contacts, or the order in which it contacts them (and it has no good reason to know those things, ever).

[IshKebab]

The simplest way to fix this problem is to support namespaces, which PyPI absolutely does need to be aware of.

[woodruffw]

This would not be meaningfully addressed by namespaces, since there's no authoritative, authenticated unique name system across indices. Two separate indices can (and will, based on what ecosystems like piwheels do[1]) advertise `foo/*`-namespaced packages, leaving installers where they are today.

(I think namespacing is a good idea regardless, if only because it eliminates artificial scarcity in a one-level namespace.)

[1]: https://www.piwheels.org/

[IshKebab]

This absolutely would be meaningfully addressed by namespaces because the typical use case is PyPI + a private repo you control. Register the namespace in both repos and you're done.

If you disagree I would love to hear of a concrete way that solution would be vulnerable.

[woodruffw]

> Register the namespace in both repos and you're done.

That’s the operative part of “authoritative.” It’s a distributed trust problem, and there’s no particular guarantee that your namespace on one index will be honored by another. Namespacing is great for eliminating scarcity on one index at a time; I don’t think it helps much with this kind of cross-index security.

[IshKebab]

Right, so it would provide a solution to the specific problem I'm taking about.

[ryan29]

> since there's no authoritative, authenticated unique name system across indices

Domains provide a globally unique namespace and ownership can be verified automatically with domain validation. Bluesky did an ok job of it, but they didn't do anything to account for domain ownership changes and re-validation is non-existent, which is disappointing to see from the first big adopter since the oversight will eventually invite criticism.

I've wanted domain validated namespaces for 5+ years. Here's a comment I made about using domain validated namespaces in package managers a couple of years ago [1]:

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I think one possible solution to that would be to assume namespaces can have their ownership changed and build something that works with that assumption.

Think along the lines of having 'pypi.org/example.com' be a redirect to an immutable organization; 'pypi.org/abcd1234'. If a new domain owner wants to take over the namespace they won't have access to the existing account and re-validating to take ownership would force them to use a different immutable organization; 'pypi.org/ef567890'.

If you have a package locking system (like NPM), it would lock to the immutable organization and any updates that resolve to a new organization could throw a warning and require explicit approval. If you think of it like an organization lock:

    v1:

        pypi.org/example.com --> pypi.org/abcd1234

    v2:

        pypi.org/example.com --> pypi.org/ef123456

If you go from v1 to v2 you know there was an ownership change or, at the very least, an event that you need to investigate.

Losing control of a domain would be recoverable because existing artifacts wouldn't be impacted and you could use the immutable organization to publish the change since that's technically the source of truth for the artifacts. Put another way, the immutable organization has a pointer back the current domain validated namespace:

    v1:

        pypi.org/abcd1234 --> example.com

    v2:

        pypi.org/abcd1234 --> example.net

If you go from v1 to v2 you know the owner of the artifacts you want has moved from the domain example.com to example.net. The package manager could give a warning about this and let an artifact consumer approve it, but it's less risky than the change above because the owner of 'abcd1234' hasn't changed and you're already trusting them.

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1. https://news.ycombinator.com/item?id=32754029