copyPackages only copies the latest package on non-deb PPAs

[Dan Ryan]

This is a follow up to lp#2022095

As part of several security team projects that interface with artifactory, we maintain some PPAs that use artifactory as a backend. We are trying to use the copyPackages API to move packages between several of these repositories.

We are now able to copyPackages() successfully, however, we have run into the following issues:

* copyPackages() only copies a single version of a given package. Because we must provide only a list of source package names to the api call, we have no control over which version is copied, but launchpad only seems to copy one version of a given package. I do not know how that version is selected, but I suspect it is either the most recently modified/released version, or the latest version. As we are managing python packages here, we are not bound by archive-like restrictions whereby we keep only one version of each package, so the normal assumptions that would apply to the archive do not apply to us. We probably need a way to specify either the version(s) we want, or to just copy all of the versions.

* copyPackages() does not copy all artifacts. In some instances, we have built architecture specific wheels for a package (e.g. for arm+amd64). Even for the version of the package selected, launchpad does not copy both the arm and the amd64 wheel. It appears to choose only one wheel (for every case I examined, it copied the arm wheel). Again, I'm not sure how it is making this choice, maybe it is the most recently uploaded wheel?

Thanks for investigating!

[Colin Watson (cjwatson)]

Please try `copyPackage` and see if you get along any better with that. It at least accepts a `version` argument.

[Dan Ryan (techalchemy)]

`copyPackage` works to copy targeted versions, but it does not resolve the issue with missing architecture specific wheels.

It however brings about another issue -- I tried copying multiple versions of `setuptools` but received numerous error emails like the following:

> Launchpad encountered an error during the following operation: copying package setuptools. setuptools 62.3.4 in focal (version older than the setuptools 65.3.0 in focal published in focal)

so it appears the standard archive restriction might need some adjustment to lift this restriction