an example of an sensible task to install Mattermost app and database

ansible-task-mattermost.yml

---
- name: internal mattermost network
  docker_network:
    name: mm.int.network

- name: create db container
  docker_container:
    name: mattermost-db
    image: postgres:{{ mattermost_db_version }}
    restart_policy: unless-stopped
    volumes:
      - "{{ mattermost_volume_dir }}/mm/db/var/lib/postgresql/data:/var/lib/postgresql/data"
      - /etc/localtime:/etc/localtime:ro
    env:
      POSTGRES_USER: "{{ mm_db_user }}"
      POSTGRES_PASSWORD: "{{ mm_db_password }}"
      POSTGRES_DB: "{{ mm_db_name }}"
    labels:
      "{{ mm_db_traefik_labels }}"
    networks:
      - name: mm.int.network
    pull: yes
    healthcheck:
      test: ["CMD-SHELL", "pg_isready -U mmuser -d mattermost"]
      interval: 1m30s
      timeout: 10s
      retries: 3
      start_period: 30s

- name: create app container
  docker_container:
    name: mattermost-app
    image: mattermost/mattermost-team-edition:{{ mattermost_app_version }}
    restart_policy: unless-stopped
    volumes:
      - "{{ mattermost_volume_dir }}/app/mattermost/config:/mattermost/config:rw"
      - "{{ mattermost_volume_dir }}/app/mattermost/data:/mattermost/data:rw"
      - "{{ mattermost_volume_dir }}/app/mattermost/logs:/mattermost/logs:rw"
      - /etc/localtime:/etc/localtime:ro
    env:
    # set same as db credentials and dbname
      MM_USERNAME: "{{ mm_db_user }}"
      MM_PASSWORD: "{{ mm_db_password }}"
      MM_DBNAME: "{{ mm_db_name }}"
      DB_HOST: mattermost-db
    labels:
      "{{ mm_traefik_labels }}"
    networks:
      - name: mm.int.network
      - name: traefik.int.network