The Koji hub does not have an option to configure the port for the DB server, and psycopg2 doesn't allow you to pass a "server:port" string as a host. This pull request adds the missing DBPort option.
PR #884
This was fixed by PR #884, but wasn't closed.
This was included in the 1.16.0 release
Metadata Update from @mikem: - Issue close_status updated to: Fixed - Issue status updated to: Closed (was: Open)
Metadata Update from @tkopecek: - Issue set to the milestone: 1.16
This issue has been migrated to Fedora Forge: https://forge.fedoraproject.org/koji/koji/issues/886
Please continue any further discussion there.