在安裝 docker 之前，有一些套件是必需要用到，使用 ansible 統一部署安裝：目前個人覺得可程式化部署最方便
增加以下變數清單:
其實一般照原則是要統一放在 vars.yml，為了能讓大家更了解直接寫在全域變數較容易理解

vars:
  requried_packages:
    - apt-transport-https
    - ca-certificates
    - curl
    - gnupg-agent
    - software-properties-common  

主程式說明:
部署程式跟之前的差別如下:
1.增加 list vars
2.利用項目迴圈安裝

- hosts: web7
  name: play-test
  gather_facts: no
  become: yes
  vars:
    ansible_become: yes 
    ansible_become_method: sudo
    ansible_become_pass: docker

    requried_packages:
      - apt-transport-https
      - ca-certificates
      - curl
      - gnupg-agent
      - software-properties-common  
  tasks:

    - name: Install required packages
      apt:
        name: "{{ item }}"
        state: latest
        update_cache: true
      loop: "{{ requried_packages }}"     

執行以下程式:

ansible-playbook -i inventory.ini playbook6.yml

成功畫面如下:

joulong@joulong1:~/playbook/docker$ ansible-playbook -i inventory.ini playbook6.yml

PLAY [play-test] *********************************************************************************************************************************************************************************************

TASK [Install required packages] *****************************************************************************************************************************************************************************
changed: [server1] => (item=apt-transport-https)
changed: [server1] => (item=ca-certificates)
changed: [server1] => (item=curl)
changed: [server1] => (item=gnupg-agent)
changed: [server1] => (item=software-properties-common)

PLAY RECAP ***************************************************************************************************************************************************************************************************
server1                    : ok=3    changed=1    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0