matrix-docker-ansible-deploy/roles/matrix-server/tasks/self_check/self_check_dns.yml

---

# This requires the dnspython library and will fail with a friendly error when unavailable.
- name: Check DNS SRV record
  set_fact:
    result_dig_srv: "{{ lookup('dig', ('_matrix._tcp.' + hostname_identity + './SRV'), 'flat=0', wantlist=False) }}"

- name: Fail if DNS SRV record missing
  fail:
    msg: "It appears the DNS SRV record for {{ hostname_identity }} is not set up correctly (the record is missing). See the 'Configuring DNS' documentation for this playbook."
  when: "result_dig_srv == 'NXDOMAIN'"

- name: Fail if DNS SRV record incorrect
  fail:
    msg: >
      It appears the DNS SRV record for {{ hostname_identity }} is not set up correctly.
      Expected it to point to `{{ (hostname_matrix + '.') }}` (port 8448).
      Found it pointing to `{{ result_dig_srv.target }}` (port {{ result_dig_srv.port }}).
      See the 'Configuring DNS' documentation for this playbook.
  when: "result_dig_srv.target != (hostname_matrix + '.') or result_dig_srv.port != 8448"

- name: Report correct DNS SRV record
  debug:
    msg: "The DNS SRV record for {{ hostname_identity }} points to {{ hostname_matrix }}, as expected"