After looking at David Wheeler's PGXN and David Cantrell's CPAN snapshots, I've come up with a story. Tell me if you think this makes sense (or not):
Historically, CPAN mirrors have always been static files. In other words, the paths in the 02packages file always pointed directly to some physical file on disk. This made it possible to access mirrors the with the older ftp:// and file:// protocols supported by CPAN.pm. It also made synchronizing the mirrors easy with tools like rsync. This has worked well for a long time. But the need to support older protocols limits the flexibility of a CPAN mirror. If you drop support for ftp:// and file://, and just focus on http:// then things can become more interesting. This open the door for a CPAN server (like the PGXN::Manager) that can do all sorts of things. For example, it could serve up distros that are spread across multiple remote machines. Or they could be stored in version control system or database. Or you could present a view of the mirror that meets certain criteria, such as by time, or cpantesters results, or by author, or by kwalitee scores, or by some other metadata (like http://cp2011-05an.barnyard.co.uk/). The concept of a CPAN server also provides a convenient hook for plugging in other services, like a private PAUSE or MetaCPAN. I'm not saying that *the* CPAN should work this way. I'm just suggesting that a *private* CPAN could work this way. Jeffrey Thalhammer Imaginative Software Systems vcard: http://www.imaginative-software.com/contact/jeff.vcf
