ansible with_dict 在提供 set_fact 变量时失败

Question

I am trying to dynamically provide dictionary name for interface variables.

My ansible task looks like this.

- name: Setting interface list
  set_fact:
    one_fact: "{{ host_name }}_interfaces"

- name: deb
  debug: var={{ one_fact }}

- name: Managing Interfaces
  ios_interface:
    enabled: "{{ item['value']['enabled'] }}"
    name: "{{ item['key'] }}"
    state: "{{ item['value']['state'] }}"
  with_dict: "{{ one_fact }}"

Dictionary looks something like this

---
h1_interfaces:
  Ethernet1/1:
    description: Firewall
    enabled: true
    speed: auto
    state: present
  Ethernet1/2:
    description: asd
    enabled: true
    speed: auto
    state: present
h2_interfaces:
  Ethernet1/1:
    description: Firewall
    enabled: true
    speed: auto
    state: present
  Ethernet1/2:
    description: asd
    enabled: true
    speed: auto
    state: present

When i set with_dict: {{ one_fact }} i get an error FAILED: => {"msg": "with_dict expects a dict"} But when i provide with with_dict: {{ h1_interfaces }} it works like a charm. What am i doing wrong?

Answer 1

Apparently you have a variable host_name too, which is set to h1 or h2 , and you want to access the dictionaries: h1_interfaces / h2_interfaces .

To construct dynamically the variable name and access its value, you should use the lookup plugin , please see below task:

  - name: Setting interface list
    set_fact:
      one_fact: "{{ lookup('vars', myvar + '_interfaces') }}"
    vars:
      myvar: "{{ host_name }}"

and a slightly altered playbook to demonstrate the result:

playbook:

---
- hosts: localhost
  gather_facts: false
  vars:
    host_name: h1
    h1_interfaces:
      Ethernet1/1:
        description: Firewall
        enabled: true
        speed: auto
        state: present
      Ethernet1/2:
        description: asd
        enabled: true
        speed: auto
        state: present
    h2_interfaces:
      Ethernet1/1:
        description: Firewall
        enabled: true
        speed: auto
        state: present
      Ethernet1/2:
        description: asd
        enabled: true
        speed: auto
        state: present
    
 
  tasks:

  - name: Setting interface list
    set_fact:
      one_fact: "{{ lookup('vars', myvar + '_interfaces') }}"
    vars:
      myvar: "{{ host_name }}"

  - name: deb
    debug: var=one_fact

  - name: Managing Interfaces
    debug:
      msg: "enabled: {{ item['value']['enabled'] }}, name: {{ item['key'] }}, state: {{ item['value']['state'] }}"
    with_dict: "{{ one_fact }}"

result:

TASK [Managing Interfaces] *********************************************************************************************************************************************************************************************
ok: [localhost] => (item={'key': 'Ethernet1/1', 'value': {'description': 'Firewall', 'enabled': True, 'speed': 'auto', 'state': 'present'}}) => {
    "msg": "enabled: True, name: Ethernet1/1, state: present"
}
ok: [localhost] => (item={'key': 'Ethernet1/2', 'value': {'description': 'asd', 'enabled': True, 'speed': 'auto', 'state': 'present'}}) => {
    "msg": "enabled: True, name: Ethernet1/2, state: present"
}

cheers