A Home Assistant script to make a Sonos speaker join whichever speaker is currently playing

join_playing_sonos.yaml

# Add this to your scripts.yaml file

join_playing_sonos:
  description: "Make a Sonos spaker join whichever speaker is current playing."
  fields:
    target:
      description: "Entity ID of the Sonos which you'd like to make join the group"
      example: "media_player.office"
  variables:
    group_owner: '{{ state_attr((integration_entities("sonos") | select("is_state", "playing") | first), "group_members") | first }}'
  sequence:
    - alias: "Join Sonos to currently playing group"
      service: media_player.join
      data:
        group_members:
          - "{{ target }}"
      target:
        entity_id: "{{ group_owner }}"