Re: Problem with packagesource::sites in setup

[Jon Turney <jon dot turney at dronecode dot org dot uk>]

On 15/03/2018 21:23, Ken Brown wrote:
> I think we're currently mishandling packagesource::sites when several 
> libsolv repos contain the same version of a package.  If I'm not 
> mistaken, we create a new packageversion pv for each repo, and 
> pv.source()->sites contains a single site, corresponding to that repo.
>
> So we never take advantage of the fact that we have more than one mirror 
> (or mirror directory) from which we can potentially obtain an archive 
> for the package.

Hmm... I think this is going to interact with the package repositories 
release: label.  If they are both "cygwin", then one will overwrite the 
other.  If they are different, then we'll have 2 separate libsolv repos.

In the first case, I'm not sure that having the same package available 
from more than one package repository mirror was ever was doing anything 
terribly useful (i.e. it doesn't make the download any faster, or more 
reliable)

But, yeah, what we are doing currently is probably wrong.

In the second case, it's possible for the length/hash of the "same" 
version to be different, so it's not clear in what sense they really are 
the same, and I think it's random which one we're going to get 
(silently), which is unhelpful at best...

> I think the way to fix this is to consolidate all the packageversions pv 
> into a single one, which knows about all the sites.
>
> This could be handled by packagemeta::add_version().  When it replaces 
> an existing version, it could remove the old one from the pool after 
> copying the sites information.  In order to obtain the sites 
> information, it would have to be able to query the libsolv pool, so we 
> would have to internalize repo data as we go along, presumably in the 
> IniDBBuilderPackage destructor.
>
> Does this sound about right?  If so, I'll try to prepare a patch.  Or 
> maybe there's a better/easier way to solve the problem.