Ansible Loop循环控制

Ansible 2.5之前主要使用with_ <lookup>关键字来创建循环，循环关键字基本上类似于with_list，with_items。

Ansible 2.5开始官网推荐使用Loop来进行循环控制。

示例1 Loop数组循环：

---
- name: create user
  hosts: dev
  tasks:
    - name: create user
      user:
        name: "{{ item }}"
        state: present
      loop:
      - user01
      - user02
      - user03

    - name: set password
      shell: echo '12345678' | passwd --stdin "{{ item }}"
      loop:
      - user01
      - user02
      - user03

示例2 vars传递数组给Loop循环

---
- name: create user
  hosts: dev
  vars:
     users:
      - user01
      - user02
      - user03
  tasks:
    - name: create user
      user:
        name: "{{ item }}"
        state: present
      loop: "{{ users }}"

    - name: set password
      shell: echo '12345678' | passwd --stdin "{{ item }}"
      loop: "{{ users }}"

示例3 Loop字典循环：

---
- name: create user
  hosts: dev
  tasks: 
  - name: create user and group
    user:
        name: "{{ item.name }}"
        group: "{{ item.groups }}"
    loop:
    - {name: 'user01', groups: 'wheel'}
    - {name: 'user02', groups: 'root'}

示例4 vars传递字典给Loop循环

---
- name: loop test
  hosts: dev
  vars:
    users:
    - user: 'user01'
      group: 'wheel'
    - user: 'user02'
      group: 'root'
  tasks:
    - name: debug
      user:
        name: "{{ item.user }}"
        group: "{{ item.group }}"
      loop: "{{ users }}"

示例5 vars传递字典给Loop循环，并使用dict filter

---
- name: loop test
  hosts: dev
  vars:
    users:
      user: 'user01'
      groups: 'root'
  tasks:
    - name: debug
      debug:
        msg: "{{ item.key }}  {{ item.value }}"
      loop: "{{ users|dict2items }}"　　# dict2items 是 jinjia2 filter