Ansible：从每个主机的寄存器减少到变量

Question

---
- hosts: all
  tasks:
  - name: Read the file
    command: cat the_file
    register: the_file

  - name: Reduce them
    set_fact:
      result: "{{ the_file.stdout }}"
      reduce: yes # magic option

当the_file在每个主机中分别写成"a","b","c"时，是否可以得到像["a", "b", "c"]或"abc"这样的变量？

主机之间不是通过 ssh 连接的，而是仅来自 playbook 运行一个。

Answer 1

extract 来自 hostvars

的变量

    - set_fact:
        result: "{{ ansible_play_hosts_all|
                    map('extract', hostvars, 'the_file')|list }}"
      run_once: true

给予

result: [a, b, c]

如果你愿意，你可以加入项目

    - set_fact:
        result: "{{ ansible_play_hosts_all|
                    map('extract', hostvars, 'the_file')|join }}"
      run_once: true

给予

result: abc

请参阅 Special Variables 并根据您的需要调整主机列表。

Ansible：从每个主机的寄存器减少到变量

Ansible: reduce to the variable from registers of each host

ansible