unattended-upgrades must always be installed

[filnko]

removed detection of init system.
the package unattended-upgrades needs to be always installed regardless of init system.

[Voronenko]

Perhaps I would explain about init systems detection:

root@automaticupdates:~# cat /etc/lsb-release | head -2
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=14.04
root@automaticupdates:~# ls /etc/systemd/system/apt-daily.timer.d/
ls: cannot access /etc/systemd/system/apt-daily.timer.d/: No such file or directory
root@automaticupdates:~# 

Currently yes, role targets only xenial with systemd magic.
But in nearest plans there is also to support classic ubuntu 14.04 , at least until end of support.

Thus, I would propose leave init system detection

[filnko]

ok, in that case it makes sense.
ansible already provides the init system in the variable {{ ansible_service_mgr }}, so theres no need to detect it yourself.

also unattended-upgrades must be installed always because it doesn't work on systemd otherwise.

[Voronenko]

@filnko Yep, I know also more often study gather_facts output.

I.e. I first wrote detection, later discovered variable. But as a lot of roles re-use recipe, use it historically
But it is now ansible_service_mgr for unknown cases/

---
  - name: USE | Detect upstart system
    shell: |
      if [[ `/sbin/init --version 2> /dev/null` =~ upstart ]]; then echo upstart;
      elif [[ `systemctl` =~ -\.mount ]]; then echo systemd;
      elif [[ -f /etc/init.d/cron && ! -h /etc/init.d/cron ]]; then echo sysv-init;
      else echo {{ansible_service_mgr | default('UNKNOWN')}};
      fi
    become: yes
    args:
      executable: /bin/bash
    register: upstart_detect_raw
    changed_when: False

  - set_fact:
      upstart_system: "{{upstart_detect_raw.stdout}}"