matrix-docker-ansible-deploy/roles/matrix-client-cinny/tasks/validate_config.yml

---
- name: Fail if required Cinny settings not defined
  ansible.builtin.fail:
    msg: >
      You need to define a required configuration setting (`{{ item }}`) to use Cinny.      
  when: "vars[item] == '' or vars[item] is none"
  with_items:
    - "matrix_client_cinny_default_hs_url"