Needs fontconfig integration

[Sebastien Bacher]

Seems that those variables are needed for fontconfig to work, ideally snapcraft would handle them for you

# Not good, needed for fontconfig
export XDG_DATA_HOME=$SNAP/usr/share

# Font Config
export FONTCONFIG_PATH=$SNAP/etc/fonts/config.d
export FONTCONFIG_FILE=$SNAP/etc/fonts/fonts.conf

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Bruno Nova (brunonova)]

I confirm that these are needed, at least for Java Swing applications.
They crash without this with a NullPointerException at sun.awt.FontConfiguration.getVersion(FontConfiguration.java:1264).

[Bruno Nova (brunonova)]

I also needed to add these variables to package a Racket/Scheme game that I made several years ago.

I also needed to bundle some fonts with the snap, namely fonts-dejavu. Without them, instead of letters, only rectangles were displayed. In case of Java, it didn't even start.

Snapcraft should handle these variables.
I also think that snapd should grant access to the fonts and fontconfig directories/files of the system and user. That would be really useful for things like LibreOffice.

[QkiZ (qkiz)]

Snapcraft applications should use their own fontconfig files, not from host system because of compatibility issues. I made a snap for application that is no longer in repositories. My host OS is 20.04 and snap base OS is 18.04. This causes incompatibilities between snaps and system.

[QkiZ (qkiz)]

Workaround for this issue:
(in apps section)
apps:
  some_app:
    command: some_app
    environment:
      XDG_DATA_HOME: $SNAP/usr/share
      FONTCONFIG_PATH: $SNAP/etc/fonts/conf.d
      FONTCONFIG_FILE: $SNAP/etc/fonts/fonts.conf

Of course this only works in devmode. After switching to strict mode program in snap ends with error that it can't reach /etc/fonts/fonts.conf file. I think should be resolved by adding interface.

[Maciej Borzecki (maciek-borzecki)]

This will probably be a part of larger work related to picking up bits of /etc from the host.