Example 15

hosts.yml

centos:
  hosts:
    provisioner:
      ansible_connection: local
    centos1:
      ansible_host: '192.168.77.22'
ubuntu:
  hosts:
    ubuntu1:
      ansible_host: '192.168.77.23'

playbook.yml

- name: Example playbook
  hosts: provisioner
  gather_facts: false
  vars:
    vars_directory_content: "{{ lookup('pipe', 'ls {{ playbook_dir }}')}}"
  tasks:
    - name: Set the custom fact
      set_fact:
        fact_directory_content: "{{ lookup('pipe', 'ls')}}"
    - name: Initial value for vars_directory_content
      debug:
        msg: "{{ vars_directory_content }}"
    - name: Initial value for fact_directory_content
      debug:
        msg: "{{ fact_directory_content }}"
    - name: Add a file to the playbook directory
      file:
        state: touch
        dest: "{{ playbook_dir}}/var_vs_fact"
    - name: Post-modification value for vars_directory_content
      debug:
        msg: "{{ vars_directory_content }}"
    - name: Post-modification value for fact_directory_content
      debug:
        msg: "{{ fact_directory_content }}"

Tip

In Ansible vars and facts act in a different manner. Knowing when and how to use on of these concepts or another is key to successful playbook writing.

Execute the following command

ansible-playbook playbook.yml

What is the expected output of the command ?

The var will reflect the changes in the directory content. Variables are evaluated in runtime, whereas facts as the name suggests are set in stone.