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

roles/mongodb/tasks/install.yml

@@ -4,6 +4,11 @@
 # https://www.mongodb.com/docs/manual/installation/
 
 
+- name: Record (initial) available disk space
+  shell: df -PB1 $(findmnt / -o SOURCE -n) | awk 'NR==2 {print $4}'
+  register: df1
+
+
 # 1. INSTALL MongoDB PACKAGES AND/OR BINARIES
 
 # 2019-02-02: Sugarizer with Node.js 10.x requires MongoDB 2.6+ so
@@ -367,6 +372,17 @@
 
 # 3. RECORD MongoDB AS INSTALLED
 
+- name: Record (final) available disk space
+  shell: df -PB1 $(findmnt / -o SOURCE -n) | awk 'NR==2 {print $4}'
+  register: df2
+
+- name: Add 'mongodb_disk_usage = {{ df1.stdout|int - df2.stdout|int }}' to {{ iiab_ini_file }}
+  ini_file:
+    path: "{{ iiab_ini_file }}"    # /etc/iiab/iiab.ini
+    section: mongodb
+    option: mongodb_disk_usage
+    value: "{{ df1.stdout|int - df2.stdout|int }}"
+
 - name: "Set 'mongodb_installed: True'"
   set_fact:
     mongodb_installed: True