iiab/roles/cups/tasks/install.yml

# 2021-07-11: (1) WE NEED TO GET http://box:631 AND http://box.lan:631 WORKING.
# /var/log/cups/error_log* shows "400 Bad Request" errors as follows:
#
# Request from "localhost" using invalid Host: field "box:631".
# Request from "localhost" using invalid Host: field "box.lan:631".
#
# (2) WE NEED NGINX PROXY TO GET http://box/print WORKING RELIABLY ON ALL OS's.

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

- name: Add user '{{ iiab_admin_user }}' to Linux group 'lpadmin' for remote administration (or modify default 'SystemGroup lpadmin' in /etc/cups/cups-files.conf -- in coordination with ~14 '@SYSTEM' lines in /etc/cups/cupsd.conf)
  command: "gpasswd -a {{ iiab_admin_user | quote }} lpadmin"    # iiab-admin
  #command: "gpasswd -d {{ iiab_admin_user | quote }} lpadmin"


# WARNING: 'apt install cups' AND 'apt install --reinstall cups'
# UNFORTUNATELY DO *NOT* RECREATE /etc/cups/cupsd.conf IF A PRIOR
# INSTALL OF CUPS EXISTED!  SO OPTION #1 OR #2 ARE NEEDED BELOW:

# OPTION #1: OLD WAY (BRITTLE)
#
# - name: Install our own /etc/cups/cupsd.conf from template, to permit local LAN admin
#   template:
#     src: cupsd.conf.j2
#     dest: /etc/cups/cupsd.conf

# OPTION #2: NEW WAY (MORE FUTURE-PROOF, WE HOPE!)

- name: FILE /etc/cups/cupsd.conf WILL BE CREATED BY THE ~5 STANZAS BELOW...
  meta: noop
# - debug:
#     msg: FILE /etc/cups/cupsd.conf WILL BE CREATED BY THE ~5 STANZAS BELOW...

- name: Copy /usr/share/cups/cupsd.conf.default to /etc/cups/cupsd.conf (root:lp, 0640) -- a timestamped backup of the prior 'cupsd.conf' is saved in /etc/cups
  copy:
    src: /usr/share/cups/cupsd.conf.default
    dest: /etc/cups/cupsd.conf
    owner: root
    group: lp
    mode: 0640
    backup: yes

- name: (Re)Start 'cups' and 'cups-browsed' systemd services -- CUPS DAEMON MUST BE RUNNING FOR 'cupsctl' COMMAND JUST BELOW
  systemd:
    daemon_reload: yes
    name: "{{ item }}"
    state: restarted
  with_items:
    - cups
    - cups-browsed

- name: Run 'cupsctl --remote-admin --share-printers --user-cancel-any --debug-logging' for /var/log/cups/error_log (if cups_enabled) -- REPEATED USE OF 'cupsctl' COMMANDS CAN *DAMAGE* /etc/cups/cupsd.conf BY ADDING DUPLICATE LINES (AND WORSE!) -- SO PLEASE ALSO MANUALLY RUN 'sudo cupsctl' AND 'sudo cupsd -t' TO VERIFY /etc/cups/cupsd.conf
  command: cupsctl --remote-admin --share-printers --user-cancel-any --debug-logging

# 2021-07-11: BOTH FLAGS *CANNOT* BE USED TOGETHER -- CHOOSE ONE OR THE OTHER:
# (1) '--remote-admin' AS ABOVE, OR (2) '--remote-any' AS BELOW.
# (RUN 'cupsctl' WITHOUT PARAMETERS TO CONFIRM THIS!)

# - name: Run 'cupsctl --remote-any --share-printers --user-cancel-any --debug-logging' for /var/log/cups/error_log (if cups_enabled) -- REPEATED USE OF 'cupsctl' COMMANDS CAN *DAMAGE* /etc/cups/cupsd.conf BY ADDING DUPLICATE LINES (AND WORSE!) -- SO PLEASE ALSO MANUALLY RUN 'sudo cupsctl' AND 'sudo cupsd -t' TO VERIFY /etc/cups/cupsd.conf
#   command: cupsctl --remote-any --share-printers --user-cancel-any --debug-logging

# 2021-07-11: In theory 'cupsctl' stanzas could be put in enable-or-disable.yml
# BUT LET'S AVOID THAT -- AS REPEATED USE OF 'cupsctl' COMMANDS CAN *DAMAGE*
# /etc/cups/cupsd.conf BY ADDING DUPLICATE LINES (AND WORSE!)
#
# FYI repeated use of 'cupsctl' commands also removes comments and blank lines.
#
# - name: Run 'cupsctl --no-remote-admin --no-remote-any --no-share-printers --no-user-cancel-any --no-debug-logging' (if not cups_enabled) -- REPEATED USE OF 'cupsctl' COMMANDS CAN *DAMAGE* /etc/cups/cupsd.conf BY ADDING DUPLICATE LINES (AND WORSE!) -- SO PLEASE ALSO MANUALLY RUN 'sudo cupsctl' AND 'sudo cupsd -t' TO VERIFY /etc/cups/cupsd.conf
#   command: cupsctl --no-remote-admin --no-remote-any --no-share-printers --no-user-cancel-any --no-debug-logging
#   when: not cups_enabled

- name: "2021-07-11: UNFORTUNATELY http://box:631 AND http://box/print DO NOT YET WORK RELIABLY -- CUPS NEEDS TO WORK FROM MANY MORE URL'S THAN JUST http://localhost:631 AND http://192.168.0.x:631 AND http://172.18.96.1:631 -- please help us find the correct directive(s) for /etc/cups/cupsd.conf and /etc/nginx/conf.d/cups.conf followed by 'systemctl restart cups' and 'systemctl restart nginx'"
  lineinfile:
    path: /etc/cups/cupsd.conf
    line: "{{ item }}"
    insertbefore: '^Listen .*/run/cups/cups.sock$'    # Also matches old form: '^Listen /var/run/cups/cups.sock$'
  with_items:
    - "#ServerAlias *"
    - "#ServerName {{ iiab_hostname }}.{{ iiab_domain }}"    # box.lan
    - "#Listen {{ lan_ip }}:631"    # 172.18.96.1
    - "Listen 127.0.0.1:631"
    - "#Listen 0.0.0.0:631"
    - "#Listen *:631"

- name: "OPTIONAL: Change 'MaxLogSize 0' (no log rotation) to 'MaxLogSize 1m' (log rotation at 1MB) in /etc/cups/cupsd.conf (EITHER WAY LOG BLOAT IS A RISK!)"
  lineinfile:
    path: /etc/cups/cupsd.conf
    regexp: '^MaxLogSize '
    insertbefore: 'Listen '
    firstmatch: yes
    line: "MaxLogSize 1m"    # CUPS Documentation (claims!) log rotation at "1m" is the default.  But In Practice: 'MaxLogSize 0' (no log rotation) is now part of /usr/share/cups/cupsd.conf.default

# REMINDER: 3 systemd services should be restarted (cups, cups-browsed, nginx)
# within enable-or-disable.yml, so /etc/cups/cupsd.conf (ETC) take effect!


# RECORD CUPS AS INSTALLED

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

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