Added a trick to reduce the snap size

This trick reduces the size from 110 to 87 MBytes.

scripts/launch.sh

@@ -0,0 +1,7 @@
+#!/bin/sh
+
+export GIO_MODULE_DIR=$SNAP/gnome-platform/usr/lib/$ARCH_TRIPLET/gio/modules
+export GSETTINGS_SCHEMA_DIR=$SNAP/usr/share/glib-2.0/schemas:$SNAP/gnome-platform/usr/share/glib-2.0/schemas${GSETTINGS_SCHEMA_DIR:+:$GSETTINGS_SCHEMA_DIR}
+export GST_PLUGIN_PATH=$SNAP/gnome-platform/usr/lib/$ARCH_TRIPLET/gstreamer-1.0${GST_PLUGIN_PATH:+:$GST_PLUGIN_PATH}
+export GST_PLUGIN_SYSTEM_PATH=$GST_PLUGIN_SYSTEM_PATH:$SNAP/gnome-platform/usr/lib/$ARCH_TRIPLET/gstreamer-1.0
+exec "$@"

snapcraft.yaml

@@ -31,7 +31,7 @@ layout:
 
 apps:
   epiphany:
-    command: bin/snapcraft-preload $SNAP/usr/bin/epiphany
+    command: scripts/launch $SNAP/bin/snapcraft-preload $SNAP/usr/bin/epiphany
     extensions: [ gnome ]
     plugs:
       - audio-playback
@@ -52,14 +52,52 @@ apps:
       - upower-observe
     desktop: usr/share/applications/org.gnome.Epiphany.desktop
     environment:
-      GSETTINGS_SCHEMA_DIR: $SNAP/usr/share/glib-2.0/schemas
-      GIO_MODULE_DIR: $SNAP/gnome-platform/usr/lib/$CRAFT_ARCH_TRIPLET/gio/modules/
-      LD_LIBRARY_PATH: ${LD_LIBRARY_PATH:+$LD_LIBRARY_PATH:}$SNAP/usr/lib/$CRAFT_ARCH_TRIPLET/epiphany:$SNAP/usr/lib/$CRAFT_ARCH_TRIPLET:$SNAP/usr/lib/$CRAFT_ARCH_TRIPLET/blas:$SNAP/usr/lib/$CRAFT_ARCH_TRIPLET/lapack
+      ARCH_TRIPLET: $CRAFT_ARCH_TRIPLET
+      LD_LIBRARY_PATH: $SNAP/usr/lib/$CRAFT_ARCH_TRIPLET/epiphany:$SNAP/usr/lib/$CRAFT_ARCH_TRIPLET:$SNAP/usr/lib/$CRAFT_ARCH_TRIPLET/blas:$SNAP/usr/lib/$CRAFT_ARCH_TRIPLET/lapack${LD_LIBRARY_PATH:+:$LD_LIBRARY_PATH}
 
 parts:
+# Install all stage packages, find files provided by the base and
+# platform snap and ensure they aren't duplicated in this snap
+  packages:
+    plugin: nil
+    stage-packages:
+      - gstreamer1.0-clutter-3.0
+      - gstreamer1.0-gl
+      - gstreamer1.0-gtk3
+      - gstreamer1.0-libav
+      - gstreamer1.0-plugins-base
+      - gstreamer1.0-plugins-good
+      - gstreamer1.0-plugins-bad
+      - gstreamer1.0-pulseaudio
+      - libarchive13
+      - libglu1-mesa
+      - libgpm2
+      - libjavascriptcoregtk-4.0-18
+      - libnettle8
+      - libslang2
+      - libsphinxbase3
+    build-snaps: [core22, gtk-common-themes, gnome-42-2204]
+    override-prime: |
+      set -eux
+      craftctl default
+      for snap in "core22" "gtk-common-themes" "gnome-42-2204"; do
+        cd "/snap/$snap/current"
+        find . -type f,l -exec rm -f "$CRAFT_PRIME/{}" \;
+      done
+      cd $CRAFT_PRIME
+      rm -f usr/lib/$CRAFT_ARCH_TRIPLET/webkit2gtk-4.0
+      rm -f usr/lib/$CRAFT_ARCH_TRIPLET/webkit2gtk-4.1
+      mkdir -p usr/lib/$CRAFT_ARCH_TRIPLET
+      ln -s ../../../gnome-platform/usr/lib/$CRAFT_ARCH_TRIPLET/webkit2gtk-4.0 usr/lib/$CRAFT_ARCH_TRIPLET/
+      ln -s ../../../gnome-platform/usr/lib/$CRAFT_ARCH_TRIPLET/webkit2gtk-4.1 usr/lib/$CRAFT_ARCH_TRIPLET/
+      cd $CRAFT_PRIME/usr/share/glib-2.0/schemas
+      glib-compile-schemas .
+
+
 # epiphany needs access to /dev/shm/
   snapcraft-preload:
     source: https://github.com/sergiusens/snapcraft-preload.git
+    after: [ packages ]
     source-depth: 1
 # ext:updatesnap
 #   version-format:
@@ -99,22 +137,6 @@ parts:
       - nettle-dev
       - python-gi-dev
       - libgirepository1.0-dev
-    stage-packages:
-      - gstreamer1.0-clutter-3.0
-      - gstreamer1.0-gl
-      - gstreamer1.0-gtk3
-      - gstreamer1.0-libav
-      - gstreamer1.0-plugins-base
-      - gstreamer1.0-plugins-good
-      - gstreamer1.0-plugins-bad
-      - gstreamer1.0-pulseaudio
-      - libarchive13
-      - libglu1-mesa
-      - libgpm2
-      - libjavascriptcoregtk-4.0-18
-      - libnettle8
-      - libslang2
-      - libsphinxbase3
     stage:
       - -usr/bin/gtk-update-icon-cache
       - -usr/lib/*/gtk-3.0/3.0.0/printbackends/libprintbackend*.so*
@@ -136,22 +158,9 @@ parts:
       - -usr/lib/*/libsecret-1.so.*
       - -usr/share/glib-2.0/schemas/org.gtk*
 
-  # Find files provided by the base and platform snap and ensure they aren't
-  # duplicated in this snap
-  cleanup:
-    after: [epiphany]
-    plugin: nil
-# ext:updatesnap
-#   version-format:
-#     ignore: true
-    build-snaps: [core22, gtk-common-themes, gnome-42-2204]
-    override-prime: |
-      set -eux
-      for snap in "core22" "gtk-common-themes" "gnome-42-2204"; do
-        cd "/snap/$snap/current" && find . -type f,l -name *.so.* -exec rm -f "$CRAFT_PRIME/{}" \;
-      done
-      cd $CRAFT_PRIME
-      rm -f usr/lib/$CRAFT_ARCH_TRIPLET/webkit2gtk-4.0
-      rm -f usr/lib/$CRAFT_ARCH_TRIPLET/webkit2gtk-4.1
-      ln -s ../../../gnome-platform/usr/lib/$CRAFT_ARCH_TRIPLET/webkit2gtk-4.0 usr/lib/$CRAFT_ARCH_TRIPLET/
-      ln -s ../../../gnome-platform/usr/lib/$CRAFT_ARCH_TRIPLET/webkit2gtk-4.1 usr/lib/$CRAFT_ARCH_TRIPLET/
+  scripts:
+    after: [ epiphany ]
+    plugin: dump
+    source: scripts
+    organize:
+      launch.sh: scripts/launch

squashfs-root/snap/command-chain/desktop-launch

@@ -0,0 +1,5 @@
+#!/bin/bash
+
+set -- "${SNAP}/gnome-platform/command-chain/desktop-launch" "$@"
+# shellcheck source=/dev/null
+source "${SNAP}/snap/command-chain/run"

squashfs-root/snap/command-chain/hooks-configure-fonts

@@ -0,0 +1,5 @@
+#!/bin/bash
+
+set -- "${SNAP}/gnome-platform/command-chain/hooks-configure-fonts" "$@"
+# shellcheck source=/dev/null
+source "${SNAP}/snap/command-chain/run"

squashfs-root/snap/command-chain/run

@@ -0,0 +1,25 @@
+#!/bin/bash
+
+if [ -z "$1" ]; then
+  echo "run <command>"
+  exit 1
+fi
+
+if [ -z "${SNAP}" ]; then
+  echo "Not running inside a snap context: SNAP not declared"
+  exit
+fi
+
+
+if [ ! -f "$1" ]; then
+  echo "Content snap command-chain for $1 not found: ensure slot is connected"
+  exit
+fi
+
+# emulate "exec $@" using "source"
+# have to disable "unused variables" because checkshell doesn't know that $BASH_ARGV0 is $0
+# shellcheck disable=SC2034  # Unused variables left for readability
+BASH_ARGV0=$1
+shift
+# shellcheck source=/dev/null
+source "$0"