---
- name: Add repo file
  template: src=mariadb_ubuntu.list.j2 dest=/etc/apt/sources.list.d/mariadb.list owner=root group=root mode=0644
  register: mariadb_list

- name: Add repo key
  apt_key: id=1BB943DB url=http://keyserver.ubuntu.com/pks/lookup?op=get&search=0xCBCB082A1BB943DB state=present
  register: mariadb_key
  when: ansible_distribution_version | version_compare('16.04', 'lt')

- name: Add apt key for mariadb for Ubuntu >= 16.04
  apt_key: id=C74CD1D8 url=http://keyserver.ubuntu.com/pks/lookup?op=get&search=0xF1656F24C74CD1D8 state=present
  register: mariadb_key
  when: ansible_distribution_version | version_compare('16.04', 'ge')

- name: Update apt cache
  apt: update_cache=yes
  when: mariadb_list.changed == True or mariadb_key.changed == True

- name: Unattended package installation
  shell: export DEBIAN_FRONTEND=noninteractive
  changed_when: false

- name: Install MariaDB
  apt: pkg={{ item }} state=present
  with_items:
    - mariadb-server
    - python-mysqldb # required to set the MySQL password using ansible
...