iiab/roles/vnstat/tasks/install.yml

- name: Record (initial) disk space used
  shell: df -B1 --output=used / | tail -1
  register: df1


- name: Install 'vnstat' package
  package:
    name: vnstat
    state: present


# Similar code block in roles/network/tasks/detected_network.yml (line ~35) and roles/network/tasks/computed_network.yml (lines ~74 and ~110)
- name: "Setting iiab_wan_iface to '{{ ansible_default_ipv4.alias }}' -- using ansible_default_ipv4.alias if detected"
  set_fact:
    iiab_wan_iface: "{{ ansible_default_ipv4.alias }}"
  when: ansible_default_ipv4.gateway is defined

# 2023-05-01: Probably no longer nec, as line 'Interface ""' in /etc/vnstat.conf (as installed by apt) automatically selects the default interface
- name: Insert 'Interface "{{ iiab_wan_iface }}"' into /etc/vnstat.conf
  lineinfile:
    path: /etc/vnstat.conf
    regexp: '^Interface '
    line: 'Interface "{{ iiab_wan_iface }}"'

# - name: Install /etc/vnstat.conf from template
#   template:
#     src: vnstat.conf.j2
#     dest: /etc/vnstat.conf
#     mode: '0744'


# 2023-05-01: https://github.com/vergoh/vnstat/issues/134#issuecomment-663836557
- name: 'Precautionary Start & Enable of vnstat.service, to mitigate intermittent #3539 (''Failed to open database "/var/lib/vnstat/vnstat.db" in read-only mode'') during WAN db creation just below'
  systemd:
    name: vnstat
    daemon_reload: true
    state: started
    enabled: true

- name: Create database for WAN to collect vnStat data
  shell: /usr/bin/vnstat -i {{ iiab_wan_iface }}

- name: Create database for LAN to collect vnStat data if not appliance config
  shell: /usr/bin/vnstat -i {{ iiab_lan_iface }}
  when: iiab_lan_iface is defined and iiab_lan_iface != "none"


# RECORD vnStat AS INSTALLED

- name: Record (final) disk space used
  shell: df -B1 --output=used / | tail -1
  register: df2

- name: Add 'vnstat_disk_usage = {{ df2.stdout|int - df1.stdout|int }}' to {{ iiab_ini_file }}
  ini_file:
    path: "{{ iiab_ini_file }}"    # /etc/iiab/iiab.ini
    section: vnstat
    option: vnstat_disk_usage
    value: "{{ df2.stdout|int - df1.stdout|int }}"

- name: "Set 'vnstat_installed: True'"
  set_fact:
    vnstat_installed: True

- name: "Add 'vnstat_installed: True' to {{ iiab_state_file }}"
  lineinfile:
    path: "{{ iiab_state_file }}"    # /etc/iiab/iiab_state.yml
    regexp: '^vnstat_installed'
    line: 'vnstat_installed: True'