How to check in Ansible if group exist in Inventory file or not?

Question

My case is:

If group doesn't exist in inventory file then I want to throw an error instead of getting a warning like: 'No host matched'.

Ansible version: 2.4

Answer 1

Add a play checking for group existence to the top of your playbook. Use groups magic variable in the condition:

---
- hosts: localhost
  gather_facts: no
  connection: local
  tasks:
    - fail:
      when: "'my_group' not in groups"