flutter-apps-layer: add init service to automatically launch Flutter demo

This commit introduces a dynamic layer that extends the flutter-apps layer by
adding an init service to automatically launch the Flutter demo on boot.

https://onedigi.atlassian.net/browse/DEL-9380

Signed-off-by: Arturo Buzarra <arturo.buzarra@digi.com>

meta-digi-dey/conf/layer.conf

@@ -28,6 +28,8 @@ BBFILES_DYNAMIC += " \
     qt6-layer:${LAYERDIR}/dynamic-layers/qt6-layer/*/*/*.bbappend \
     qt6-layer:${LAYERDIR}/dynamic-layers/qt6-layer/${DEY_SOC_VENDOR}/*/*/*.bb \
     qt6-layer:${LAYERDIR}/dynamic-layers/qt6-layer/${DEY_SOC_VENDOR}/*/*/*.bbappend \
+    flutter-apps-layer:${LAYERDIR}/dynamic-layers/flutter-apps-layer/*/*/*/*.bb \
+    flutter-apps-layer:${LAYERDIR}/dynamic-layers/flutter-apps-layer/*/*/*/*.bbappend \
 "
 
 BBFILE_COLLECTIONS += "digi-dey"

meta-digi-dey/dynamic-layers/flutter-apps-layer/recipes-graphics/flutter-apps/first-party/files/flutter-demo-init

@@ -0,0 +1,111 @@
+#!/bin/sh
+#===============================================================================
+#
+#  Copyright (C) 2025 by Digi International Inc.
+#  All rights reserved.
+#
+#  This program is free software; you can redistribute it and/or modify it
+#  under the terms of the GNU General Public License version 2 as published by
+#  the Free Software Foundation.
+#
+#
+#  !Description: Initialize Flutter demo
+#
+#===============================================================================
+
+readonly DEMO_NAME="##FLUTTER_DEMO_NAME##"
+readonly FLUTTER_VERSION="##FLUTTER_SDK_TAG##"
+readonly FLUTTER_MODE="##FLUTTER_MODE##"
+readonly DEMO_PATH="/usr/share/flutter/${DEMO_NAME}/${FLUTTER_VERSION}/${FLUTTER_MODE}/"
+readonly DEMO_TITLE="Flutter Demo Application"
+readonly PID_FILE="/run/${DEMO_NAME}.pid"
+
+log() {
+	if type "systemd-cat" >/dev/null 2>/dev/null; then
+		systemd-cat -p "${1}" -t "${DEMO_NAME}" printf "%s" "${2}"
+	fi
+	logger -p "${1}" -t "${DEMO_NAME}" "${2}"
+}
+
+get_demo_pid() {
+	local pid="$(pgrep -f ${DEMO_PATH})"
+
+	[ -n "${pid}" ] && { echo "${pid}"; return 0; }
+
+	return 1
+}
+
+check_is_running() {
+	local pid
+
+	if [ -s "${PID_FILE}" ]; then
+		pid="$(cat ${PID_FILE})"
+	else
+		pid="$(get_demo_pid)"
+		echo "${pid}" > ${PID_FILE}
+	fi
+
+	if [ "${pid}" ]; then
+		kill -0 "${pid}" >/dev/null 2>&1 && return 0
+	fi
+
+	rm -f "${PID_FILE}"
+
+	return 1
+}
+
+stop() {
+	check_is_running || return
+
+	local pid="$(cat ${PID_FILE})"
+	kill -TERM "${pid}" >/dev/null 2>&1
+
+	local STOP_TIMEOUT="5"
+	for i in $(seq ${STOP_TIMEOUT}); do
+		check_is_running || { log info "stopped"; break; }
+		if [ "${i}" -eq ${STOP_TIMEOUT} ]; then
+			log warning "stop: ${DEMO_NAME} did not stop gracefully"
+			kill -KILL "${pid}" >/dev/null 2>&1
+		fi
+		sleep 1
+	done
+}
+
+start() {
+	check_is_running && { log warning "start: ${DEMO_NAME} ALREADY running"; exit 0; }
+
+	# Launch demo
+	flutter-pi --release ${DEMO_PATH} >/dev/null 2>&1 &
+
+	if [ $? -eq 0 ]; then
+		echo $! > ${PID_FILE}
+		log info "$(cat ${PID_FILE})"
+		log info "started"
+	fi
+}
+
+case "$1" in
+	start)
+		echo -n "Starting ${DEMO_TITLE}: "
+		start
+		echo "done."
+		;;
+	stop)
+		stop
+		echo -n "Stopping ${DEMO_TITLE}: "
+		if [ -n "`/bin/pidof ${DEMO_PATH}`" ] ; then
+			echo "FAIL"
+		else
+			echo "OK"
+		fi
+		;;
+	restart)
+		stop
+		sleep 1
+		start
+		;;
+	*)
+		echo "Usage: $0 {start|stop|restart}"
+		exit 1
+		;;
+esac

meta-digi-dey/dynamic-layers/flutter-apps-layer/recipes-graphics/flutter-apps/first-party/files/flutter-demo-init.service

@@ -0,0 +1,11 @@
+[Unit]
+Description=Flutter Demo Application
+
+[Service]
+Type=forking
+PIDFile=/run/##FLUTTER_DEMO_NAME##.pid
+ExecStart=/etc/flutter-demo-init start
+ExecStop=/etc/flutter-demo-init stop
+
+[Install]
+WantedBy=multi-user.target

meta-digi-dey/dynamic-layers/flutter-apps-layer/recipes-graphics/flutter-apps/first-party/flutter-samples-veggieseasons_%.bbappend

@@ -0,0 +1,47 @@
+# Copyright (C) 2025, Digi International Inc.
+
+FILESEXTRAPATHS:prepend:dey := "${THISDIR}/files:"
+
+SRC_URI:append = " \
+    file://flutter-demo-init \
+    file://flutter-demo-init.service \
+"
+
+FLUTTER_DEMO_NAME ?= "${PN}"
+FLUTTER_MODE ?= "${FLUTTER_APP_RUNTIME_MODES}"
+
+inherit update-rc.d systemd
+
+do_install:append() {
+	# Install systemd service
+	if ${@bb.utils.contains('DISTRO_FEATURES', 'systemd', 'true', 'false', d)}; then
+		# Install systemd unit files
+		install -d ${D}${systemd_unitdir}/system
+		install -m 0644 ${WORKDIR}/flutter-demo-init.service ${D}${systemd_unitdir}/system/
+		sed -i -e "s,##FLUTTER_DEMO_NAME##,${FLUTTER_DEMO_NAME},g" \
+			"${D}${systemd_unitdir}/system/flutter-demo-init.service"
+	fi
+
+	# Install wrapper bootscript to launch Flutter demo on boot
+	install -d ${D}${sysconfdir}/init.d
+	install -m 0755 ${WORKDIR}/flutter-demo-init ${D}${sysconfdir}/flutter-demo-init
+	ln -sf ${sysconfdir}/flutter-demo-init ${D}${sysconfdir}/init.d/flutter-demo-init
+	sed -i -e "s@##FLUTTER_SDK_TAG##@${FLUTTER_SDK_TAG}@g" \
+		   -e "s@##FLUTTER_MODE##@${FLUTTER_MODE}@g" \
+		   -e "s@##FLUTTER_DEMO_NAME##@${FLUTTER_DEMO_NAME}@g" \
+		   "${D}${sysconfdir}/flutter-demo-init"
+}
+
+PACKAGES =+ "${PN}-init"
+FILES:${PN}-init = " \
+    ${sysconfdir}/flutter-demo-init \
+    ${sysconfdir}/init.d/flutter-demo-init \
+    ${systemd_unitdir}/system/flutter-demo-init.service \
+"
+
+INITSCRIPT_PACKAGES += "${PN}-init"
+INITSCRIPT_NAME:${PN}-init = "flutter-demo-init"
+INITSCRIPT_PARAMS:${PN}-init = "start 99 3 5 . stop 20 0 1 2 6 ."
+
+SYSTEMD_PACKAGES = "${PN}-init"
+SYSTEMD_SERVICE:${PN}-init = "flutter-demo-init.service"

meta-digi-dey/recipes-graphics/packagegroups/packagegroup-dey-flutter.bb

@@ -9,6 +9,7 @@ inherit packagegroup
 RDEPENDS:${PN} += " \
     flutter-pi \
     flutter-samples-veggieseasons \
+    flutter-samples-veggieseasons-init \
 "
 
 RDEPENDS:${PN}:append:imxgpu = " \