Testing a task result which uses a loop?

Question

So the first task is always skipped because RedHat 8 is detected which should trigger the fail module to run but this gets skipped also. Is works fine without the loop though.

- name: installing packages
  hosts: ansible2
  ignore_errors: true
  vars_files: varsfile
  tasks:
  - name: install software based on OS distro and version
    yum:
      name: "{{ item.name }}"
      state: latest
    loop: "{{ packages }}"
    when: >
       ( ansible_distribution == "RedHat" and ansible_distribution_major_version is version('12', '>=')  )
       or
       ( ansible_distribution == "CentOS" and ansible_distribution_major_version | int >= 8 )
    register: result
  - fail:
      msg: error {{ ansible_hostname }} does not meet minimum requirements
    when: result is skipped

Answer 1

Regarding

So the first task is always skipped because RedHat 8 is detected which should trigger the fail module to run but this gets skipped also.

with a small test setup and a debug task for the variable name to debug

---
- hosts: test.example.com
  become: false
  gather_facts: true

  tasks:

  - name: Install software based on OS distro and version
    debug:
      msg: "{{ ansible_distribution }} {{ ansible_distribution_major_version }}"
    register: result
    when: ansible_distribution == "RedHat" and ansible_distribution_major_version is version('12', '>=')
    with_items: ['pkg1', 'pkg2']

  - name: Show result
    debug:
      var: result

  - fail:
      msg: "Error: {{ ansible_hostname }} does not meet minimum requirements"
    when: result.results[0].skipped

resulting into an output of

TASK [Gathering Facts] ********************************
ok: [test.example.com]

TASK [Show result] ************************************
ok: [test.example.com] =>
  result:
    changed: false
    msg: All items completed
    results:
    - ansible_loop_var: item
      changed: false
      item: pkg1
      skip_reason: Conditional result was False
      skipped: true
   ...

TASK [fail] *******************************************
fatal: [test.example.com]: FAILED! => changed=false
  msg: 'Error: test does not meet minimum requirements'

you can see that the loop will create a list.

  - name: Show result
    debug:
      var: result.results | type_debug

TASK [Show result] ****************
ok: [test.example.com] =>
  result.results | type_debug: list

Therefore you need to set the Conditional to when: result.results[0].skipped.

---

Regarding

Is works fine without the loop though.

it is recommended to simplify your use case with the following approach

  - name: Install software based on OS distro and version
    yum:
      name: "{{ packages }}"
      state: latest

according the yum module Notes

When used with a loop: each package will be processed individually, it is much more efficient to pass the list directly to the name option.

and as it is faster and consumes less resources. Furthermore the result set and conditionals are less complex.