bug#55360: bug#58375: Installer does not show what is being downloaded

["Ludovic Courtès" <ludo@gnu.org>]

Hi!

Mathieu Othacehe <othacehe@gnu.org> skribis:

>> I’m not sure it’s a good idea for ‘guix system init’: we’d be logging
>> mostly progress bars, package names, and the likes to syslog—not super
>> useful.  So I’d suggest not capturing stdout of ‘guix system init’.
>
> In the bug report https://issues.guix.gnu.org/57983 capturing the 'guix
> system init' output highlighted a "guix substitute" crash. So it does
> seem like a useful mechanism, especially while 56005 is still open.

Hmm right.  <https://issues.guix.gnu.org/56005> is not
installer-specific, so it’s annoying that we have to prepare for that,
but we can’t deny such bugs exist and prevent installation.

If we really want to capture the output of ‘guix system init’, then we
need to open a pseudo-terminal with ‘openpty’ & co. instead of ‘pipe’ in
‘run-external-command-with-handler’.  That may be relatively easy
actually.

But then I think this should be used sparsely, maybe only for ‘guix
system init’.

> Now the current situation is also not really acceptable.

Nope.  :-)

> What about hiding the "guix system init" output completely and display
> a progress bar page instead?

I don’t think we can do that (with grafts, only part of the build plan
is known upfront so we don’t even know beforehand how many items will be
built/downloaded).

Also, I think there are two strategies: either we run ‘guix system
init’, in which case we let its output through, or we integrate ‘guix
system init’ functionality in the installer so we have more fine-grain
control over the process, in which case we could also have more
graphical output or something.

That second solution is a lot of work, though.

Thanks,
Ludo’.