使用已定义的参数规范验证传递给 ansible-playbook 的参数

Question

我们想要运行以下剧本与 yml 文件 - ansible-playbook install_os.yml

playbook install_os.yml 运行良好，但现在我们要添加参数验证 <machine name>,<machine IP>。

如下：

ansible-playbook install_os.yml --limit RHEL01,73.22.3.44

从我的观点来看，两个参数都应该被识别为字符串（不验证有效 IP）并且在 <machine name> 到 <machine IP> 之间，我们应该设置 , 分隔符

那么，是否可以验证字符串？如果其中一个或两个未定义则退出？

Answer 1

您可以在特殊变量 ansible_limit 的帮助下访问 ansible-playbook 的参数中指定的限制。

从那时起，您可以 assert 根据您的业务需求选择 --limit 值。

例如：

- hosts: all
  gather_facts: no

  tasks:
    - assert: 
        that: 
          ## We have exactly one comma, separating two hosts
          - ansible_limit | split(',') | length == 2
          ## We have a string before the comma
          - (ansible_limit | split(',')).0 is string
          ## We have a non-empty string before the comma
          - (ansible_limit | split(',')).0 | length > 0
          ## We have a string after the comma
          - (ansible_limit | split(',')).1 is string
          ## We have a non-empty string after the comma
          - (ansible_limit | split(',')).1 | length > 0
          ## 'all', which has a wildcard meaning, 
          ## is not one of the two hosts separated by the comma
          - "'all' not in ansible_limit | split(',')"
          ## We do not have any character having a special meaning in the limit
          ## see: https://docs.ansible.com/ansible/latest/user_guide/intro_patterns.html#common-patterns
          - "'@' not in ansible_limit"
          - "':' not in ansible_limit"
          - "'!' not in ansible_limit"
          - "'&' not in ansible_limit"
          - "'*' not in ansible_limit"
      run_once: true

这可能会将其限制为您想要的用例。
这就是说，请注意 --limit is an existing flag with its own behaviour, so, based on what you are aiming for, you could also be better with an extra parameter passed in command line.

使用已定义的参数规范验证传递给 ansible-playbook 的参数

Validates arguments passed to ansible-playbook with a defined argument specification

linux

ansible

ansible-facts