vps/roles/mailserver/tasks/backup.yml

- name: "Backup PostgreSQL stalwart database & {{ volumes['mailserver_datadir'] }} directory"
  shell: >
    docker exec postgres
    pg_dump -c {{ role_name }} |
    borg create
    --compression lzma
    "{{ borg_repodir }}::{{ role_name }}-{now:%Y-%m-%d_%H-%M-%S}"
    "{{ volumes['mailserver_datadir'] }}"
    -
    --stdin-name dump_{{ role_name }}.sql
  environment:
    DOCKER_HOST: "{{ docker_host }}"
    BORG_PASSCOMMAND: "cat {{ borg_passphrase_file }}"
  become: true

- name: Prune borg repository
  command:
    cmd: |
      borg prune
      --glob-archives='{{ role_name }}-*'
      {{ borg_prune_options }}
      {{ borg_repodir }}
  environment:
    BORG_PASSCOMMAND: "cat {{ borg_passphrase_file }}"
  become: true