docker.yml

- hosts: master
  become: yes
  vars:
    packages:
      - libffi-dev 
      - libssl-dev
      - python-pip
    docker_users:
      - pi

  tasks:
    - name: Check if Docker is already present.
      command: which docker
      failed_when: false
      changed_when: false
      register: docker_command_result

    - name: Download Docker install convenience script.
      get_url:
        url: https://get.docker.com/
        dest: /tmp/get-docker.sh
        mode: 0775

    - name: Run Docker install convenience script.
      command: /tmp/get-docker.sh
      environment:
        CHANNEL: stable
      when: docker_command_result.rc == 1

    - name: Install pip
      apt:
        name: "{{ packages }}"
        state: present

    - name: Ensure Docker is started.
      service:
        name: docker
        state: started
        enabled: true

    - name: Install Docker Compose using Pip.
      pip:
        name: docker-compose
        state: present

    - name: Ensure docker users are added to the docker group.
      user:
        name: "{{ item }}"
        group: docker
        append: true
      with_items: "{{ docker_users }}"