openstack-ansible-os_trove/extras/haproxy_trove.yml

 - service:
      haproxy_service_name: trove
      haproxy_backend_nodes: "{{ groups['trove_api'] | default([]) }}"
      haproxy_ssl: "{{ haproxy_ssl }}"
      haproxy_port: 8779
      haproxy_balance_type: http
      haproxy_backend_options:
        - "httpchk HEAD /"