ansible

yml文件中申明vars时需要用双引号包起来
- hosts: test
  vars:
      path: "{{ base_path }}/test"
      


-e EXTRA_VARS, --extra-vars=EXTRA_VARS   (优先级最高)
--extra-vars 实现vars替换、定义
--extra-vars  '{"xx":["a","b","c"]}' 
--extra-vars "hosts=test user=temp"
--extra-vars "@file.json"

cat file.json
host: test
user: temp

变量优先级：
1. extra vars(-e)
2. inventory
3. 系统发现的facts


yml中字符串转数字
tasks：
  - shell: echo "sas"
    when: start|int >= 6

满足条件，任务失败：
tasks：
  - command: echo failed
    register: command_result
    failed_when: "'failed' in command_result.stdout"


task:
  - command: echo failed
    register: command_result
    ignore_errors: true

  - name: failed echo
    fail: msg="echo failed"
    when: "'failed' in command_result.stdout"

with_first_found:

循环：
with_items:
  - { name: 'testuser1', groups: 'wheel' }
  - iter_test
  - "{{ iter_tes }}"

嵌套循环：
- name: give users access to multiple databases 
  mysql_user: name={{ item[0] }} priv={{ item[1] }}.*:ALL append_privs=yes password=foo 
  with_nested: 
    - [ 'alice', 'bob' ] 
    - [ 'clientdb', 'employeedb', 'providerdb' ]

遍历字典：
tasks: 
  - name: Print phone records 
    debug: msg="User {{ item.key }} is {{ item.value.name }} ({{ item.value.telephone }})" 
    with_dict: {'alice':{'name':'Alice Appleworth', 'telephone':'123-456-789'},'bob':{'name':'Bob Bananarama', 'telephone':'987-654-3210'} }

并行遍历：如果列表数目不匹配，用None补全（a-1,b-2,c-3,d-4,e-None）
tasks: 

  - debug: "msg={{ item.0 }} and {{ item.1 }}" 
    with_together: 
      - [ 'a', 'b', 'c', 'd','e' ] 
      - [ 1, 2, 3, 4 ]

遍历列表和索引：
- name: indexed loop demo 
  debug: "msg='at array position {{ item.0 }} there is a value {{ item.1 }}'" 
  with_indexed_items: [1,2,3,4]


重试循环： "重试次数retries" 的默认值为3，"delay"为5。
- action: shell /usr/bin/foo 
  register: result 
  until: result.stdout.find("all systems go") != -1 
  retries: 5 
  delay: 10


with_first_found: 找到一个文件，找到返回，找不到报错
with_random_choice:  随机选一个

循环程序的结果：
tasks: 
  - debug: "msg={{ item }}" 
    with_lines: ps aux

序列循环： 创建4 个用户组分表是组group1 group2 group3 group4   // with_sequence:  start=4 end=16 stride=2   4-16之间得偶数
tasks:
  - group: name=group{{ item }} state=present
    with_sequence: count=4

循环主机清单：
with_items: "{{ groups['all'] }}"
with_items: play_host    执行主机清单
with_inventory_hostnames: all
with_inventory_hostnames: all:!test   排除不在test的主机