3.saltstack使用指南：Jinja使用技巧

saltstack中使用Jinja

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jinja简介

Jinja是基于python的模板引擎，在saltstack中我们使用yaml_jinja渲染器来根据模板生产对应的配置文件，对于不同的操作系统或者不同的情况通过jinja可以让配置文件或者操作形成一种模板的编写方式。

一般在diango或者saltstack这种python环境下使用较多。

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在saltstack中使用jinja

使用的步骤比较简单：
1.File状态使用template参数 - template: jiaja
2.模板文件里面使用{{名称}}
3.File状态模块要指定变量列表：
- default:
PORT: 8080

以zabbix_agentd客户端的配置文件为例：

/etc/zabbix_agentd.conf:
  file.managed:
    - name: /etc/zabbix/zabbix_agentd.conf
    - source: salt://zabbix/files/zabbix_agentd.conf
    - templete: jinja
    - Server: {{pillar['zabbix-agent']['Zabbix_Server']}}

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一个简单示例

我们以用saltstack安装apache服务为例，在centos和ubuntu中apache服务的安装包名称是不同的，如果在一个apache.sls文件中进行安装设置，则需要借助jinja和pillar对安装包的名称进行逻辑判断。

由grains.item可以获得salt客户端的相关信息，本例中需要获取os版本：

[root@server2 pillar]# salt '*' grains.items

显示部分结果如下：

 os:
        CentOS
    os_family:
        RedHat

所以我们要对grains的os值进行判断，不同的系统我们对apache的值进行不同的设定，这样apache就相当于是可以随机应变的值。

{% if grains['os'] == 'CentOS' %}
apache: httpd
git: git 
{% elif grains['os'] == 'Debian' %}
apache: apache2
git: git-core
{% endif %}

在安装的步骤apache.sls中直接使用如下设定：

[root@server2 init]# cat apache.sls 
apache:
  pkg.installed:
    - name: {{ pillar['apache']}}

{{pillar[‘apache’]}}就是使用了pillar中的apache的值，我们根据不同的系统会选择不同的安装包名称。通过这种方式可以简化我们配置时的系统差异，只需要考虑关键的逻辑即可。

执行结果如下：

[root@server2 init]# salt '*' state.highstate 
minion-192.168.42.130:
----------
          ID: /etc/resolv.conf
    Function: file.managed
      Result: True
     Comment: File /etc/resolv.conf is in the correct state
     Started: 15:59:02.850610
    Duration: 98.457 ms
     Changes:   
----------
          ID: /etc/bashrc
    Function: file.append
      Result: True
     Comment: File /etc/bashrc is in correct state
     Started: 15:59:02.949421
    Duration: 6.435 ms
     Changes:   
----------
          ID: /etc/profile
    Function: file.append
      Result: True
     Comment: File /etc/profile is in correct state
     Started: 15:59:02.956039
    Duration: 2.451 ms
     Changes:   
----------
          ID: /etc/yum.repos.d/local_yum.repo
    Function: file.managed
      Result: True
     Comment: File /etc/yum.repos.d/local_yum.repo is in the correct state
     Started: 15:59:02.958724
    Duration: 74.73 ms
     Changes:   
----------
          ID: apache
    Function: pkg.installed
        Name: httpd
      Result: True
     Comment: The following packages were installed/updated: httpd
     Started: 15:59:03.922463
    Duration: 7044.686 ms
     Changes:   
              ----------
              httpd:
                  ----------
                  new:
                      2.4.6-40.el7.centos
                  old:

Summary for minion-192.168.42.130
------------
Succeeded: 5 (changed=1)
Failed:    0
------------
Total states run:     5
Total run time:   7.227 s
minion-192.168.42.128:
----------
          ID: /etc/resolv.conf
    Function: file.managed
      Result: True
     Comment: File /etc/resolv.conf is in the correct state
     Started: 15:59:02.895075
    Duration: 108.572 ms
     Changes:   
----------
          ID: /etc/bashrc
    Function: file.append
      Result: True
     Comment: File /etc/bashrc is in correct state
     Started: 15:59:03.003882
    Duration: 8.062 ms
     Changes:   
----------
          ID: /etc/profile
    Function: file.append
      Result: True
     Comment: File /etc/profile is in correct state
     Started: 15:59:03.012117
    Duration: 3.349 ms
     Changes:   
----------
          ID: /etc/yum.repos.d/local_yum.repo
    Function: file.managed
      Result: True
     Comment: File /etc/yum.repos.d/local_yum.repo is in the correct state
     Started: 15:59:03.015661
    Duration: 66.75 ms
     Changes:   
----------
          ID: apache
    Function: pkg.installed
        Name: httpd
      Result: True
     Comment: The following packages were installed/updated: httpd
     Started: 15:59:03.992430
    Duration: 7570.761 ms
     Changes:   
              ----------
              httpd:
                  ----------
                  new:
                      2.4.6-40.el7.centos
                  old:

Summary for minion-192.168.42.128
------------
Succeeded: 5 (changed=1)
Failed:    0
------------
Total states run:     5
Total run time:   7.757 s