task.yml

---
- name: Start a service without a port
  docker_container:
    name: service_without_port
    image: whatever
    ...
  register: my_service_status

- name: Save status
  set_fact:
    container_is_running: "{{ my_service_status.ansible_facts.docker_container.State.Running }}"

- fail:
    msg: "The service is not running"
  when: not container_is_running