duplicate service provision error message is too terse

OpenSubmitted by Ricardo Wurmus.
Details
2 participants
  • Ludovic Courtès
  • Ricardo Wurmus
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unassigned
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normal
R
R
Ricardo Wurmus wrote on 8 May 2020 22:39
(address . bug-guix@gnu.org)
87r1vu2mbb.fsf@elephly.net
“guix system” prints a very terse error message when a display manager
is added on top of %desktop-services:

guix system: error: service 'xorg-server' provided more than once

This is not very helpful, because it’s hard to tell how we got there.
Which of the selected services provide xorg-server?

It would be nice if the error message could be a little more helpful.

--
Ricardo
R
R
Ricardo Wurmus wrote on 14 May 2020 07:33
(address . 41139@debbugs.gnu.org)
87o8qrcc84.fsf@elephly.net
Ricardo Wurmus <rekado@elephly.net> writes:

Toggle quote (3 lines)
> This is not very helpful, because it’s hard to tell how we got there.
> Which of the selected services provide xorg-server?

This is the wrong question. While Shepherd services may have been
introduced to the Shepherd service graph by other general system
services, this kind of information is unavailable when just looking at
the Shepherd service itself.

The only user-facing identifiers a Shepherd service has is its
provisions. It’s hard to do better without extending Shepherd services
to include provenance information.

--
Ricardo
L
L
Ludovic Courtès wrote on 18 May 2020 00:16
(name . Ricardo Wurmus)(address . rekado@elephly.net)(address . 41139@debbugs.gnu.org)
87tv0eky1j.fsf@gnu.org
Hi,

Ricardo Wurmus <rekado@elephly.net> skribis:

Toggle quote (14 lines)
> Ricardo Wurmus <rekado@elephly.net> writes:
>
>> This is not very helpful, because it’s hard to tell how we got there.
>> Which of the selected services provide xorg-server?
>
> This is the wrong question. While Shepherd services may have been
> introduced to the Shepherd service graph by other general system
> services, this kind of information is unavailable when just looking at
> the Shepherd service itself.
>
> The only user-facing identifiers a Shepherd service has is its
> provisions. It’s hard to do better without extending Shepherd services
> to include provenance information.

Yes, or ‘fold-services’ could provide the “service extension stack”
somehow, for use in error reports.

Ludo’.
?