Comment 0 for bug 1836594

eoan:

livecd-rootfs | 2.599

bionic:

livecd-rootfs | 2.525.27

Images currently being built have non-functional snaps. Seeding never finishes, and the journal contains:

Jul 15 13:52:16 ubuntu snapd[944]: stateengine.go:102: state ensure error: devicemgr: cannot proceed without seeding "core"

seed.yaml doesn't contain core:

ubuntu@ubuntu:~$ cat /var/lib/snapd/seed/seed.yaml
snaps:
  -
    name: core18
    channel: stable
    file: core18_1055.snap
  -
    name: snapd
    channel: stable
    file: snapd_3646.snap
  -
    name: gnome-3-28-1804
    channel: stable/ubuntu-19.10
    file: gnome-3-28-1804_67.snap
  -
    name: gnome-calculator
    channel: stable/ubuntu-19.10
    file: gnome-calculator_406.snap
  -
    name: gnome-characters
    channel: stable/ubuntu-19.10
    file: gnome-characters_296.snap
  -
    name: gnome-logs
    channel: stable/ubuntu-19.10
    file: gnome-logs_61.snap
  -
    name: gnome-system-monitor
    channel: stable/ubuntu-19.10
    file: gnome-system-monitor_100.snap
  -
    name: gtk-common-themes
    channel: stable/ubuntu-19.10
    file: gtk-common-themes_1313.snap

I think it is due to this change in livecd-rootfs:

laney@raleigh (ubuntu/master↑3|✔)> git show 05e71b38409b5a7cef41ebc864223466292268bb -- live-build/functions ~/dev/canonical/release/livecd-rootfs
commit 05e71b38409b5a7cef41ebc864223466292268bb
Author: Tobias Koch <email address hidden>
Date: Thu Apr 11 17:46:00 2019 +0200

    Do not include any snaps in ubuntu-cpc:minimized builds

diff --git a/live-build/functions b/live-build/functions
index c0dfcdca..6cc87d91 100644
--- a/live-build/functions
+++ b/live-build/functions
@@ -436,6 +436,17 @@ _snap_preseed() {
         return
     fi

+ # Determine if and what core snap is needed
+ local core_snap=$(/usr/share/livecd-rootfs/snap-tool info \
+ --cohort-key="${COHORT_KEY:-}" \
+ --channel="$CHANNEL" "$SNAP_NAME" | \
+ grep '^base:' | awk '{print $2}'
+ )
+
+ if [ -n "$core_snap" ]; then
+ _snap_preseed $CHROOT_ROOT $core_snap stable
+ fi
+
     sh -c "
         set -x;
         cd \"$CHROOT_ROOT/var/lib/snapd/seed\";
@@ -544,9 +555,6 @@ snap_prepare() {
     local CUSTOM_BRAND_MODEL=${2:-generic:generic-classic}

     snap_prepare_assertions "$CHROOT_ROOT" "$CUSTOM_BRAND_MODEL"
-
- # Download the core snap
- _snap_preseed $CHROOT_ROOT core stable
 }

 snap_preseed() {

Which stopped unconditionally seeding core. But this can't be the whole story, since disco was built with that livecd-rootfs and it *does* have core.