matrix-docker-ansible-deploy/roles/custom/matrix-email2matrix/tasks/validate_config.yml

---

- name: Fail if no email2matrix mappings
  ansible.builtin.fail:
    msg: >
      You need to define at least one mapping in `matrix_email2matrix_matrix_mappings` for enabling Email2Matrix.
  when: "matrix_email2matrix_matrix_mappings | length == 0"

- name: Fail if required email2matrix settings not defined
  ansible.builtin.fail:
    msg: >-
      You need to define a required configuration setting (`{{ item.name }}`).
  when: "item.when | bool and vars[item.name] == ''"
  with_items:
    - {'name': 'matrix_email2matrix_container_network', when: true}