When you cert is expired you get back this vague reply: {{{ $ fedpkg new-sources foobar.tar.gz Uploading: 29b555096f79dbd3fbc9b96b8d443083 foobar.tar.gz Could not upload new sources: Lookaside failure. Check your cert. }}}
Instead of a generic "Check your cert." it would be more friendly to return the URL of a page where you get a brief explanation and links to get to the user account page to fetch a new certificate.
Every 6 months this happens to me and I always forget where the link is, requiring searches around the web to get to the page.
It is not a big deal, but I am sure many pakagers would find it handy.
"fedora-cert -n" will get you a new cert at the cli. and "fedora-cert -v" will let you know if your cert is expired. probably a better option would be printing a message saying "Please run 'fedora-cert -v' to verify your certificate"
Hrm, that puts some rather fedora specific stuff in the library, but I can live with it for now. We'll figure something out later.