Question

我希望在/etc/security.limits.conf中创建条目数据结构如下所示：

limits:
  - root:
    - "soft nproc unlimited"
    - "hard nfile unlimited"
  - ec2-user:
    - "soft nproc 4096"

在/etc/security.conf中生成行，如下所示：

root soft nproc unlimited root hard nfile unlimited ec2-user soft nproc 4096

数据定义生成数组字典。外部字典由用户键入，每个字典都有自己的行数组来添加。

我希望代码看起来像这个伪代码：

  for user in $limits   
     for line in $user  
        lineinfile $line ...  
     end  
  end

我无法通过Ansible看到如何做到这一点。

我一直在调试调试任务，所以我可以看到{{item}}包含的内容 - 就像这样：

 - name: limits | Set limits in /etc/security/limits.conf
     debug:
       msg: item is {{ item }}
     loop: "{{ limits }} "

但是如何获得数组的各个元素？最多可能有16个数组元素 - 每个可调参数一个。

我发现这对谷歌来说是不可能的 - 所有结果都是指Ansible docs，我已经彻底阅读了 - 并不总是理解。

任何指针都非常感激，如果我错过了一些明显的东西，我会道歉！

Answer 1

Using with_subelements:

File varloops.yml:

---
- name: Loop using with_subelements
  hosts: localhost
  connection: local
  vars_files:
    - vars.yml
  gather_facts: no


  tasks:
    - name: create a test file
      file:
        path: "{{ mytestfile }}"
        state: touch

     - name: create required entries in file
       lineinfile:
         dest: "{{ mytestfile }}"
         line: "{{ item.0.name }} {{ item.1 }}"
       with_subelements:
         - "{{ limits }}""
         - contents

File vars.yml:

---
mytestfile: ~/ansible-projects/test.txt

limits:
  - name: root
    contents:
      - "soft nproc unlimited"
      - "hard nfile unlimited"
  - name: ec2-user
    contents:
      - "soft nproc 4096"

I run this with:

$ ansible-playbook varloops.yml

and $ cat test.txt shows:

  root soft nproc unlimited
  root hard nfile unlimited
  ec2-user soft nproc 4096

lineinfile nested dict example

Answer 2

The best I've got is using subelements module. It is necessary to change the data structure, but it is also a best practice to use named elements instead of just nested lists:

   limits:
   - user: root
     limits:
     - "soft nproc unlimited"
     - "hard nfile unlimited"
   - user: ec2-user
     limits:
     - "soft nproc 4096"

And the task:

- debug:
    msg: "username is {{ item.0.user }}, security limits are {{item.1 }}"
  loop: "{{ query('subelements', limits, 'limits')  }}"

在Ansible

2 个答案: