bug#29072: The usability of Guix configurations

[myglc2]

On 11/06/2017 at 17:16 Leo Famulari writes:

> On Mon, Nov 06, 2017 at 03:12:11PM -0500, myglc2 wrote:
>> My system recently broke when I did an upgrade. I reported what I
>> thought was a bug (bug#29072) but it turned out that, because qemu
>> package code had been moved, my system configuration had become broken
>> ;-(
>> 
>> Confronted with my situation, helpful developers said "The package code
>> was moved in commit xxx" (Leo) and "maybe you have a mistake in your
>> config (Efraim)."
>
> I'm sorry that my comment was not enough on its own!
>
>> Once I understood what had happened I wondered, "Gee, I have been using
>> guix for 18 months so why didn't I figure this out myself." ;-)
>> 
>> But a less committed user might say, "Wow, Guix breaks at random, error
>> messages are hard to understand, and support is difficult."  :-(
>
> Good point.
>
>> ISTM this raises issues and questions about Guix configuration
>> usability:
>
> Indeed.
>
>> Guix config errors are reported as raw scheme errors which are not
>> user-friendly, except, perhaps, to guile users ;-) Could we improve this
>> situation by adding config troubleshooting guidance to the doc?
>
> Yes, we do try to add helpful error messages, although obviously there
> is a lot more work to be done.
[...]
>
>> Guix config errors consume meaningful amounts of user and support
>> effort. I say this because a) it took quite a few iterations to figure
>> out what was wrong in my situation, and b) google search for '"no code
>> for module" guix' finds 613 hits, which will no doubt grow linearly with
>> number of Guix users unless something is done. So I wonder, could an
>> error handler that translates into more user-friendly terms reduce user
>> frustration, increase the rate of user self help, reduce support load,
>> and effectively pay for itself?
>
> That would be awesome!
>
>> Are the current Guix config errors usable by the average GNU/Linux
>> distribution user? If not, don't they need to be improved before we call
>> it 1.0?
>
> Based on how much time it's possible to spend on IRC helping people, I'd
> say there is lots of room for improvement in this area.
>
>> Does this mean that package code must not be moved after 1.0?
>
> A couple thoughts... it would be nice if the GuixSD configuration
> example templates used a filename agnostic method of resolving module
> imports. I'm not a strong enough Schemer to evaluate the situation or
> suggest a solution, but I think that the filenames should not be
> relevant at that level. Perhaps one could use
> 'specification->package+output',
> as demonstrated in the documentation of package manifests:
>
> https://www.gnu.org/software/guix/manual/html_node/Invoking-guix-package.html
>
There is a parallel solution 
>> Finally: Should I close bug#29072? ;-)
>
> The problem of the missing QEMU patch is resolved. The broader issue of
> confusing error messages could be continued here, or elsewhere. It's up
> to you :)