Bug#944769: python3-h5py fails to import if offline due to apparent MPI failure

[Jameson Graef Rollins]

On Fri, 15 Nov 2019 15:36:23 +0800 Drew Parsons <dparsons at debian.org> wrote:
> Package: python3-h5py
> Version: 2.10.0-2
> Followup-For: Bug #944769
> Control: severity -1 important
> 
> I don't think this issue warrants severity Serious.
> 
> The failure is not triggered simply by having no network connection.
> It is only triggered if there is no network interface at all. The only
> way there can be no network interface is if the localhost loopback
> interface lo has been taken down.  This is a very artificial situation
> I think.
> 
> Ensure that the loopback interface is active with
>   ifup lo

I'm sorry, but I strongly disagree.  This situation is not artificial in
any way.  This bug was triggered by the default configuration on my
laptop when my primary network interface was down, a very common
situation.  Any application using h5py in this situation is rendered
useless, so it effectively breaks every application that imports h5py.
The severity should be set appropriately.  This package is not suitable
for release in it's current state.

I think that the base h5py packages should not be compiled against
OpenMPI.  OpenMPI is really only used in specialized circumstances,
which I suspect are not common to most users.  I don't think performance
should be degraded for the majority of users in order to boot
performance for a small subset of users in a highly specialized
circumstance.

If there is a need to provide OpenMPI support, then I humbly ask that we
do so in a separate python3-h5py-openmpi package.

Upstream was responsive when I forwarded the issue about the messages to
stderr, so they can probably help sorting out how to disable MPI support
by default if it's not obvious.

jamie.