matrix-docker-ansible-deploy/roles/custom/matrix-dendrite/tasks/validate_config.yml

---
- name: Fail if required Dendrite settings not defined
  ansible.builtin.fail:
    msg: >-
      You need to define a required configuration setting (`{{ item }}`) for using Dendrite.
  when: "vars[item] == ''"
  with_items:
    - "matrix_dendrite_registration_shared_secret"

- name: (Deprecation) Catch and report renamed settings
  ansible.builtin.fail:
    msg: >-
      Your configuration contains a variable, which now has a different name.
      Please change your configuration to rename the variable (`{{ item.old }}` -> `{{ item.new }}`).
  when: "item.old in vars"
  with_items: []