conditional test on ansible

July 28, 2023

I am trying to check if a specific package is installed or not using ansible, here’s my tasks

- name: check whether a package called {{ pkg_name }} is installed or not
  ansible.builtin.debug:
    msg: "{{ ansible_facts.packages['pkg_name'] }} is installed
  when: "pkg_name in ansible_facts.packages"

pkg_name is variable defined my me, I’ve tried different combinations with ansible_facts like:

"{{ ansible_facts.packages['pkg_name'] }} is installed"
"{{ ansible_facts.packages.{{ pkg_name }} }} is installed"

but none of the method works however if I simply put the string instead of variable it works fine ie.

ansible_facts.packages['httpd']

what is the correct syntax to check with variable?
also confirm can I pass array to it to check multiple packages at the same time

>Solution :

pkg_name is a variable. Do not quote it in the brackets

  {{ ansible_facts.packages[pkg_name] }}

Do not quote the condition

  when: pkg_name in ansible_facts.packages

Example of a complete playbook for testing

shell> cat pb.yml
- hosts: foo

  tasks:

    - package_facts:
        manager: auto

    - debug:
        msg: "{{ ansible_facts.packages[item].0.name }} is installed."
      when: item in ansible_facts.packages
      loop:
        - openssh
        - http

gives

shell> ansible-playbook pb.yml

PLAY [foo] ************************************************************************************

TASK [package_facts] **************************************************************************
ok: [foo]

TASK [debug] **********************************************************************************
ok: [foo] => (item=openssh) => 
  msg: openssh is installed.
skipping: [foo] => (item=http) 

PLAY RECAP ************************************************************************************
foo: ok=2    changed=0    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0