Re: how to make fonts available to a service?

[Timothy Sample <samplet@ngyro.com>]

Hi Robert,

Robert Vollmert <rob@vllmrt.net> writes:

>> On 12. Jul 2019, at 22:42, Robert Vollmert <rob@vllmrt.net> wrote:
>> I’m a bit at a loss right now with respect to how to make fonts available
>> to system services.
>> 
>> I’m running a service that uses rsvg-convert (from package librsvg) to
>> raster some SVG graphics. However, it appears that the default fonts
>> are missing some Unicode character.
>> 
>> It seems that I can make fonts available in my user profile by installing
>> the corresponding font package, and those would be available to rsvg-convert
>> via fontconfig via ~/.guix-profile/share/fonts. But how would I do the
>> same for a service?
>
> It turns out this was easy to fix, by adding a font package to the list
> of installed packages in the operating system definition.
>
> (and apologies for sending this to -devel instead of help-)

Just so you know, you can extend the “profile-service-type” in your
service type definition to add packages to the system profile.  It’s
kind of like having propagated inputs for your service.  The GDM service
needs to make fonts available, so it (effectively) does the following.

    (service-type (name 'gdm)
                    (extensions
                     (list ...
                           (service-extension profile-service-type
                                              (list font-cantarell))
                           ...))
                    ...)

Hope that helps!


-- Tim