Ansible 自学笔记（七）模板

  

 

修改文件nginx.conf.j2 下面行为
worker_processes {{ ansible_processor_vcpus }};

cat temnginx2.yml
- hosts: websrvs
  remote_user: root
  tasks:
    - name: template config to remote hosts
      template: src=nginx.conf.j2 dest=/etc/nginx/nginx.conf

ansible-playbook temnginx2.yml

 Playbook中template算术运算  

算法运算：
示例：
    vim nginx.conf.j2
    worker_processes {{ ansible_processor_vcpus**2 }};
    worker_processes {{ ansible_processor_vcpus+2 }};

Playbook中template for if when循环 

{% for vhost in nginx_vhosts %}

server {    #重复执行server代码
listen {{ vhost.listen | default('80 default_server') }};

{% if vhost.server_name is defined %}
server_name {{ vhost.server_name }};
{% endif %}

{% if vhost.root is defined %}
root {{ vhost.root }};
{% endif %}

{% endfor %}

when条件判断 

- hosts: websrvs
  remote_user: root
  tasks:
    - name: add group nginx
      tags: user
      user: name=nginx state=present
    - name: add user nginx
      user: name=nginx state=present group=nginx
    - name: Install Nginx
      yum: name=nginx state=present
    - name: restart Nginx
      service: name=nginx state=restarted
      when: ansible_distribution_major_version == "6"

 

示例：
tasks:
  - name: install conf file to centos7
    template: src=nginx.conf.c7.j2 dest=/etc/nginx/nginx.conf
    when: ansible_distribution_major_version == "7"
  - name: install conf file to centos6
    template: src=nginx.conf.c6.j2 dest=/etc/nginx/nginx.conf
    when: ansible_distribution_major_version == "6"

迭代：with_items

迭代：当有需要重复性执行的任务时，可以使用迭代机制
    > 对迭代项的引用，固定变量名为"item"
    > 要在task中使用with_items给定要迭代的元素列表
    > 列表格式：
         字符串
         字典

示例： 创建用户
- name: add several users
  user: name={{ item }} state=present groups=wheel   #{{ item }} 系统自定义变量
  with_items:       # 定义{{ item }} 的值和个数
    - testuser1
    - testuser2

上面语句的功能等同于下面的语句：
- name: add user testuser1
  user: name=testuser1 state=present groups=wheel
- name: add user testuser2
  user: name=testuser2 state=present groups=wheel
  
with_items中可以使用元素还可为hashes
示例：
- name: add several users
  user: name={{ item.name }} state=present groups={{ item.groups }}
  with_items:
    - { name: 'testuser1', groups: 'wheel' }
    - { name: 'testuser2', groups: 'root' }

ansible的循环机制还有更多的高级功能，具体请参见官方文档
http://docs.ansible.com/playbooks_loops.html

 

示例：将多个文件进行copy到被控端
---
- hosts: testsrv
  remote_user: root
  tasks
  - name: Create rsyncd config
    copy: src={{ item }} dest=/etc/{{ item }}
    with_items:
  - rsyncd.secrets
  - rsyncd.conf

with_itmes 嵌套子变量

with_itmes 嵌套子变量
示例
---
- hosts: testweb
  remote_user: root
  tasks:
    - name: add several users
      user: name={{ item.name }} state=present groups={{ item.groups }}
      with_items:
    - { name: 'testuser1' , groups: 'wheel'}
    - { name: 'testuser2' , groups: 'root'}