Problems trying to snap emacs

1

I’m trying to snap emacs and it works fine as a devmode snap. Since it is the norm for IDEs / editors to use classic confinement, I tried switching it to confinement: classic but now on launching it complains that the gnome platform snap is not connected (although it actually is):

amurray@sec-disco-amd64:~$ sudo snap install --classic emacs-alexmurray_26.2_amd64.snap  --dangerous
emacs-alexmurray 26.2 installed
amurray@sec-disco-amd64:~$ emacs-alexmurray.emacs
You need to connect this snap to the gnome platform snap.

You can do this with those commands:
snap install gnome-3-28-1804
snap connect emacs-alexmurray:gnome-3-28-1804 gnome-3-28-1804

amurray@sec-disco-amd64:~$ snap interfaces emacs-alexmurray
Slot                             Plug
gnome-3-28-1804:gnome-3-28-1804  emacs-alexmurray
gtk-common-themes:gtk-3-themes   emacs-alexmurray
gtk-common-themes:icon-themes    emacs-alexmurray
gtk-common-themes:sound-themes   emacs-alexmurray
amurray@sec-disco-amd64:~$ sudo snap connect emacs-alexmurray:gnome-3-28-1804 gnome-3-28-1804

The snap connect command didn’t show any errors but even then it still fails to launch in the same manner - I tried removing the whole use of the gnome-platform snap but then when launching it appears to just hang so I assume I need the desktop-launcher etc to set things up correctly. Can anyone suggest what I might need to do to get this working as classicly confined?

2

I just realised I can still use desktop-launch without the desktop-gnome-platform part and this appears to work with classic (ie emacs launches correctly) but when testing on an install of Ubuntu 19.04 I get a lot of errors about invalid fontconfig:

Fontconfig warning: "/etc/fonts/fonts.conf", line 5: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/fonts.conf", line 6: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/fonts.conf", line 6: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/fonts.conf", line 6: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/fonts.conf", line 7: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/fonts.conf", line 7: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/fonts.conf", line 9: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/10-hinting-slight.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/10-hinting-slight.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/10-hinting-slight.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/10-hinting-slight.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/10-hinting-slight.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/10-hinting-slight.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/10-hinting-slight.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/10-scale-bitmap-fonts.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/10-scale-bitmap-fonts.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/10-scale-bitmap-fonts.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/10-scale-bitmap-fonts.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/10-scale-bitmap-fonts.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/10-scale-bitmap-fonts.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/10-scale-bitmap-fonts.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/11-lcdfilter-default.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/11-lcdfilter-default.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/11-lcdfilter-default.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/11-lcdfilter-default.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/11-lcdfilter-default.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/11-lcdfilter-default.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/11-lcdfilter-default.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/20-unhint-small-vera.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/20-unhint-small-vera.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/20-unhint-small-vera.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/20-unhint-small-vera.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/20-unhint-small-vera.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/20-unhint-small-vera.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/20-unhint-small-vera.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/30-metric-aliases.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/30-metric-aliases.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/30-metric-aliases.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/30-metric-aliases.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/30-metric-aliases.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/30-metric-aliases.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/30-metric-aliases.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/40-nonlatin.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/40-nonlatin.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/40-nonlatin.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/40-nonlatin.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/40-nonlatin.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/40-nonlatin.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/40-nonlatin.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/45-generic.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/45-generic.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/45-generic.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/45-generic.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/45-generic.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/45-generic.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/45-generic.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/45-latin.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/45-latin.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/45-latin.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/45-latin.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/45-latin.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/45-latin.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/45-latin.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/49-sansserif.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/49-sansserif.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/49-sansserif.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/49-sansserif.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/49-sansserif.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/49-sansserif.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/49-sansserif.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/50-user.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/50-user.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/50-user.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/50-user.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/50-user.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/50-user.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/50-user.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/51-local.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/51-local.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/51-local.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/51-local.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/51-local.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/51-local.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/51-local.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/60-generic.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/60-generic.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/60-generic.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/60-generic.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/60-generic.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/60-generic.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/60-generic.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/60-latin.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/60-latin.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/60-latin.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/60-latin.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/60-latin.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/60-latin.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/60-latin.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/65-fonts-persian.conf", line 34: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/65-fonts-persian.conf", line 35: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/65-fonts-persian.conf", line 35: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/65-fonts-persian.conf", line 35: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/65-fonts-persian.conf", line 36: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/65-fonts-persian.conf", line 36: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/65-nonlatin.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/65-nonlatin.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/65-nonlatin.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/65-nonlatin.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/65-nonlatin.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/65-nonlatin.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/65-nonlatin.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/69-unifont.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/69-unifont.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/69-unifont.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/69-unifont.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/69-unifont.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/69-unifont.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/70-no-bitmaps.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/70-no-bitmaps.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/70-no-bitmaps.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/70-no-bitmaps.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/70-no-bitmaps.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/70-no-bitmaps.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/70-no-bitmaps.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/80-delicious.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/80-delicious.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/80-delicious.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/80-delicious.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/80-delicious.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/80-delicious.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/90-synthetic.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/90-synthetic.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/90-synthetic.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/90-synthetic.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/90-synthetic.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/90-synthetic.conf", line 6: invalid attribute 'version'
Fontconfig error: Cannot load config file from /etc/fonts/fonts.conf

Is this to be expected?

3

I don’t think it’s recommended to use desktop launchers for classic snaps. @kenvandine may know best practice for classic gtk apps.

4

It should be fine to use the desktop launchers for classic snaps, just without the content interface. In fact, it sets up some environment variables you still need. It might be more “greedy” than you need, but should be harmless. These fontconfig warnings and errors are probably harmless as well, just noise. However the cause of these might slow down the startup time by a second or two. I was actually investigating this very issue last night with another snap, I’ll post my findings here later.

Looking at your yaml, you need to drop the content interface plugs for classic. Lines 31-47 can be removed.

5

Thanks @popey and @kenvandine - next step is I want to try and make this ‘official’ - so I will create a new thread to ask about getting approval for classic confinement from the store and to have the name ‘emacs’ (unless we can just do it all in this thread?)

6

Just to follow up for anyone else looking at this thread for advice - my previous comment

I can still use desktop-launch without the desktop-gnome-platform part

is incorrect (I thought this was the case since I had not done a snapcraft clean so the desktop-gnome-platform part was still staged etc) - as such a follow up commit was needed to add back in the desktop-gnome-platform part BUT without the override-build stanza since we do not want to create the gnome-platform directory as otherwise desktop-launch will assume we have the gnome-platform content interface available (which we do not since we are classic).