Introduce run_app_container script

app_containers/.local/bin/run_app_container

@@ -0,0 +1,56 @@
+#!/usr/bin/env bash
+
+die() {
+  echo "$1" >&2
+  exit 1
+}
+
+[ -z "$CONTAINER_NAME" ] && die "\$CONTAINER_NAME not set"
+[ -z "$DISPLAY" ] && die "\$DISPLAY not set (you must run the script in a desktop environment"
+
+# From <https://liolok.com/run-desktop-app-with-systemd-nspawn-container>
+if [[ -n $DBUS_SESSION_BUS_ADDRESS ]]; then # remove prefix
+    host_bus=${DBUS_SESSION_BUS_ADDRESS#unix:path=}
+else # default guess
+    host_bus=$XDG_RUNTIME_DIR/bus
+fi
+
+if [[ -n $PULSE_SERVER ]]; then # remove prefix
+  host_pulse=${PULSE_SERVER#unix:}
+else # default guess
+  host_pulse=$XDG_RUNTIME_DIR/pulse
+fi
+
+# Default username
+run_as=user
+homedir=/home/user
+if [ "$CONTAINER_RUN_AS_ROOT" = true ]; then
+  run_as=root
+  homedir=/root
+fi
+
+sudo systemd-nspawn -M $CONTAINER_NAME \
+    `# DNS (when containers do not have their own netns)` \
+    --bind-ro=/run/systemd/resolve/stub-resolv.conf:/etc/resolv.conf \
+    `# GPU` \
+    --bind=/dev/dri/card0 \
+    --bind=/dev/shm \
+    --property=DeviceAllow='char-drm rw' \
+    `# Input devices` \
+    --bind-ro=/dev/input \
+    --property=DeviceAllow='char-input r' \
+    `# Xorg / Xwayland` \
+    --bind-ro=/tmp/.X11-unix \
+    --setenv=DISPLAY=$DISPLAY \
+    `# PulseAudio` \
+    --bind-ro=$host_pulse:/run/host/pulse \
+    --setenv=PULSE_SERVER=unix:/run/host/pulse/native \
+    `# DBus` \
+    --bind-ro=$host_bus:/run/host/bus \
+    --setenv=DBUS_SESSION_BUS_ADDRESS=unix:path=/run/host/bus \
+    `# Scaling `\
+    --setenv=GDK_SCALE="$GDK_SCALE" \
+    `# Extra params` \
+    $SYSTEMD_NSPAWN_EXTRA_ARGS \
+    `# Launch app` \
+    --user=$run_as --chdir=$homedir --as-pid2 $@