add function for desktop notification

jobhelper.sh

@@ -82,6 +82,11 @@ function j_init(){
   j_requireBinary "tee"
   j_requireBinary "touch"
 
+  # for notify-send in j_notify()
+  if [ -n "$SUDO_USER" ]; then
+    export DBUS_SESSION_BUS_ADDRESS=unix:path=/run/user/$(id -u $SUDO_USER)/bus
+  fi
+
   # j_read
 }
 
@@ -419,6 +424,30 @@ function _getFqdn(){
   # echo "INFO: FQDN is [$FQDN]"
 }
 
+# show a desktop notification using notify-send
+# param  string   summary (aka title)
+# param  string   message text
+# paran  integer  optional: exitcode; if set it adds a prefix OK or ERRROR on summary and sets urgency on error
+function j_notify(){
+  local _summary="IML BACKUP :: $1"
+  local _body="$2"
+  local _rc="$3"
+
+  local _urgency="normal"
+
+  if [ -n "$DBUS_SESSION_BUS_ADDRESS" ]; then
+    if [ -n "$_rc" ]; then
+      if [ "$_rc" = "0" ]; then
+        _summary="OK: ${_summary}"
+      else
+        _summary="ERROR: ${_summary}"
+        _urgency="critical"
+      fi
+    fi
+    su "$SUDO_USER" -c "notify-send --urgency=${_urgency} '${_summary}' '${_body}'"
+  fi
+}
+
 # ------------------------------------------------------------
 # check if it was startet with a given user
 # This is skipped if MS windows was detected with "mingw".