Re: [libvirt] [jenkins-ci PATCH] lcitool: Raise Error instead of Exception

On Mon, 2019-03-11 at 17:55 +0000, Daniel P. Berrangé wrote: > On Mon, Mar 11, 2019 at 06:48:11PM +0100, Andrea Bolognani wrote: > > This results in > > > > $ ./lcitool dockerfile dockerfile -x foo libvirt-debian-9 libvirt > > FROM debian:9 > > ./lcitool: Unsupported architecture ppc64el > > > > being printed on error, instead of the much nastier > > > > $ ./lcitool dockerfile dockerfile -x foo libvirt-debian-9 libvirt > > FROM debian:9 > > Traceback (most recent call last): > > File "./lcitool", line 704, in <module> > > Application().run() > > File "./lcitool", line 699, in run > > args.func(args) > > File "./lcitool", line 643, in _action_dockerfile > > deb_arch = Util.native_arch_to_deb_arch(args.cross_arch) > > File "./lcitool", line 126, in native_arch_to_deb_arch > > raise Exception("Unsupported architecture {}".format(native_arch)) > > Exception: Unsupported architecture foo > > I'm curious why the "Error" class exists at all ? It doesn't seem > to add anything that the normal "Exception" class can't do, and > leads to bugs like the one here. I seem to understand you're not supposed to use Exception directly, but rather define your own exception types: https://docs.python.org/3/tutorial/errors.html#user-defined-exceptions I remember reading more about this, but I can't find the source right now.