Record approx disk usage for 45 roles (to iiab.ini)

roles/nodered/tasks/install.yml

@@ -23,6 +23,11 @@
 #  when: nodejs_version != "12.x"
 
 
+- name: Record (initial) available disk space
+  shell: df -PB1 $(findmnt / -o SOURCE -n) | awk 'NR==2 {print $4}'
+  register: df1
+
+
 # BRUTAL but ensures consistency across OS's / distros like Raspbian Desktop &
 # Ubermix that often include an older version of Node-RED.  Brutal, as this
 # removes customizations on graphical desktop OS's e.g. Raspbian Desktop's:
@@ -138,6 +143,17 @@
 
 # RECORD Node-RED AS INSTALLED
 
+- name: Record (final) available disk space
+  shell: df -PB1 $(findmnt / -o SOURCE -n) | awk 'NR==2 {print $4}'
+  register: df2
+
+- name: Add 'nodered_disk_usage = {{ df1.stdout|int - df2.stdout|int }}' to {{ iiab_ini_file }}
+  ini_file:
+    path: "{{ iiab_ini_file }}"    # /etc/iiab/iiab.ini
+    section: nodered
+    option: nodered_disk_usage
+    value: "{{ df1.stdout|int - df2.stdout|int }}"
+
 - name: "Set 'nodered_installed: True'"
   set_fact:
     nodered_installed: True