galera-swarm-lxc-ansible/roles/lxc_swarm/tasks/prepare_worker_host.yml

---
- name: Install python-apt to use ansible apt module
  shell: apt update && apt install -y python-apt

- name: Ensure python and other dependencies are installed.
  apt:
    name:
      - apt-transport-https
      - ca-certificates
      - gnupg
      - python-pip
    state: present

- name: pip install docker
  pip:
    name: docker
    state: present

- name: Add docker gpg key
  apt_key: 
    url: "https://download.docker.com/linux/debian/gpg"
    state: present

- name: Add docker stable repository for debian
  apt_repository:
    repo: "deb https://download.docker.com/linux/debian stretch stable"
    state: present

- name: Install docker engine on worker nodes
  apt:
    name:
      - docker-ce

- name: Fix docker kernel module (from bridge utils) missing issue
  command: touch /.dockerenv
  run_once: true
  notify: Restart docker