feat(systemd-service-demo):Add a systemd demo

The demo includes following features:
* notifications (ready and status)
* dependencies between services (strong and week)

layers/meta-belden-coreos-demo/recipes-core/images/coreos-image-demo.bb

@@ -1,4 +1,7 @@
 DESCRIPTION = "An image that come with most of the feature available in CoreOS"
 
 inherit coreos-image
-require coreos-image-all-features
+require recipes-core/images/coreos-image-all-features.bb
+
+# demos
+IMAGE_INSTALL:append = " systemd-services-demo"

layers/meta-belden-coreos-demo/recipes-demo/systemd-services-demo/files/demo_service_1.sh

@@ -0,0 +1,15 @@
+#!/bin/sh
+
+# This is a simple example for systemd start
+PIPE="/tmp/bar"
+if [ ! -p "$PIPE" ]; then
+        mkfifo $PIPE
+fi
+
+COUNTER=0
+
+while : ; do
+        COUNTER=$((COUNTER + 1))
+        echo "Hello Service 1: ${COUNTER}" > /tmp/bar
+        sleep 10
+done

layers/meta-belden-coreos-demo/recipes-demo/systemd-services-demo/files/demo_service_2.sh

@@ -0,0 +1,18 @@
+#!/bin/sh
+
+# This is a simple example for systemd start
+
+PIPE="/tmp/baz"
+if [ ! -p "$PIPE" ]; then
+        mkfifo $PIPE
+fi
+
+COUNTER=0
+
+while : ; do
+        COUNTER=$((COUNTER + 1))
+        echo "Hello Service 2: ${COUNTER}" > /tmp/baz
+        sleep 10
+done
+
+

layers/meta-belden-coreos-demo/recipes-demo/systemd-services-demo/files/demo_service_3.sh

@@ -0,0 +1,28 @@
+#!/bin/sh
+
+# This is an example for systemd-notify
+# You can see the status with systemctl status demoservice3.service
+
+
+PIPE="/tmp/foo"
+if [ ! -p "$PIPE" ]; then
+        mkfifo  -m 666 $PIPE
+fi
+
+sleep 10  # Assume we are doing some time consuming initialization
+
+# Notify systemd that we are ready
+systemd-notify --ready --status="Waiting for data ..."
+
+while : ; do
+        read a < /tmp/foo
+        # Tell systemd your current status
+        systemd-notify --status="Processing $a"
+
+        # Do something with $a …
+        sleep 10
+
+        systemd-notify --status="Waiting for data ..."
+done
+
+

layers/meta-belden-coreos-demo/recipes-demo/systemd-services-demo/files/demoservice1.service

@@ -0,0 +1,10 @@
+[Unit]
+Description=systemd demo
+After=demoservice3.service
+Wants=demoservice3.service
+
+[Service]
+ExecStart=/usr/bin/demo_service_1.sh
+
+[Install]
+WantedBy=multi-user.target

layers/meta-belden-coreos-demo/recipes-demo/systemd-services-demo/files/demoservice2.service

@@ -0,0 +1,10 @@
+[Unit]
+Description=systemd demo for showing dependencies
+After=demoservice3.service
+Requires=demoservice3.service
+
+[Service]
+ExecStart=/usr/bin/demo_service_2.sh
+
+[Install]
+WantedBy=multi-user.target

layers/meta-belden-coreos-demo/recipes-demo/systemd-services-demo/files/demoservice3.service

@@ -0,0 +1,9 @@
+[Unit]
+Description=systemd demo for showing notifications
+
+[Service]
+Type=notify
+ExecStart=/usr/bin/demo_service_3.sh
+
+[Install]
+WantedBy=multi-user.target

layers/meta-belden-coreos-demo/recipes-demo/systemd-services-demo/systemd-services-demo.bb

@@ -0,0 +1,34 @@
+DESCRIPTION = "Example that shows how services can be started by using systemd unit files"
+SECTION = "examples"
+DEPENDS = ""
+LICENSE = "CLOSED"
+
+FILESEXTRAPATHS:prepend := "${THISDIR}/files:"
+
+SRC_URI = " file://demo_service_1.sh \
+            file://demoservice1.service  \
+            file://demo_service_2.sh \
+            file://demoservice2.service  \
+            file://demo_service_3.sh \
+            file://demoservice3.service  \
+"
+
+inherit systemd
+
+SYSTEMD_SERVICE:${PN} += "demoservice1.service"
+SYSTEMD_SERVICE:${PN} += "demoservice2.service"
+SYSTEMD_SERVICE:${PN} += "demoservice3.service"
+SYSTEMD_AUTO_ENABLE = "enable"
+
+do_install(){
+    install -d ${D}${bindir}
+    install -m 0777 ${WORKDIR}/demo_service_1.sh ${D}${bindir}
+    install -m 0777 ${WORKDIR}/demo_service_2.sh ${D}${bindir}
+    install -m 0777 ${WORKDIR}/demo_service_3.sh ${D}${bindir}
+    install -d ${D}${systemd_unitdir}/system
+    install -m 0644 ${WORKDIR}/demoservice1.service ${D}${systemd_unitdir}/system
+    install -m 0644 ${WORKDIR}/demoservice2.service ${D}${systemd_unitdir}/system
+    install -m 0644 ${WORKDIR}/demoservice3.service ${D}${systemd_unitdir}/system
+}
+
+FILES:${PN} += " ${systemd_unitdir}/system/demoservice*.service ${bindir}/demo_service_*.sh"

layers/meta-belden-coreos/recipes-core/images/coreos-image-all-features.bb

@@ -7,3 +7,6 @@ IMAGE_FEATURES += "${@bb.utils.contains("MACHINE_FEATURES", "efi", "swupdate", "
 
 IMAGE_INSTALL:append = " packagegroup-core-full-cmdline"
 IMAGE_INSTALL:append = "${@bb.utils.contains("IMAGE_FEATURES", "swupdate", " swupdate-www", "", d)}"
+
+# development tools
+IMAGE_INSTALL:append = " systemd-analyze"