Service Calls

Various components allow calling services when a certain event occurs. The most common one is calling a service when an automation trigger happens. But a service can also be called from a script or via the Amazon Echo.

The configuration options to call a config are the same between all components and are described on this page.

Examples on this page will be given as part of an automation component configuration but different approaches can be used for other components too.

Use the service developer tool in the frontend to discover available services.

The basics

Call the service homeassistant.turn_on on the entity group.living_room. This will turn all members of group.living_room on. You can also omit entity_id and it will turn on all possible entities.

automation:
- trigger:
    platform: sun
    event: sunset
  action:
    service: homeassistant.turn_on
    entity_id: group.living_room

Passing data to the service call

You can also specify other parameters beside the entity to target. For example, the light turn on service allows specifying the brightness.

automation:
- trigger:
    platform: sun
    event: sunset
  action:
    service: light.turn_on
    entity_id: group.living_room
    data:
      brightness: 120
      rgb_color: [255, 0, 0]

Use templates to decide which service to call

You can use templating support to dynamically choose which service to call. For example, you can call a certain service based on if a light is on.

automation:
- trigger:
    platform: sun
    event: sunset
  action:
    service_template: >
      {% if states.sensor.temperature | float > 15 %}
        switch.turn_on
      {% else %}
        switch.turn_off
      {% endif %}
    entity_id: switch.ac

Use templates to determine the attributes

Templates can also be used for the data that you pass to the service call.

automation:
- trigger:
    platform: sun
    event: sunset
  action:
    service_template: thermostat.set_temperature
    data_template:
      entity_id: >
        {% if is_state('device_tracker.paulus', 'home') %}
          thermostat.upstairs
        {% else %}
          thermostat.downstairs
        {% endif %}
      temperature: {{ 22 - distance(states.device_tracker.paulus) }}