infra-role-alertmanager/tasks/discover.yml

---
- name: Get data centers
  uri:
    url: '{{ consul_catalog_url }}/datacenters'
  register: data_centers

- name: Get AlertManager node addresses
  uri:
    url: '{{ consul_catalog_url }}/service/{{ alertmanager_service_name }}?dc={{ item }}'
    method: GET
    validate_certs: no
  with_items: '{{ data_centers.json }}'
  register: alertmanager_services

- name: Extract IP addresses
  set_fact:
    alertmanager_cluster_peers: |
      {{ alertmanager_services.results
      | sum(attribute="json", start=[])
      | sort(attribute='Node')
      | list }}