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layout	title	description	date	sidebar	comments	sharing	footer	redirect_from
page	Automation Templating	Advanced automation documentation using templating.	2016-04-24 08:30 +0100	true	false	true	true	/getting-started/automation-templating/

In Home Assistant 0.19 we introduced a new powerful feature: variables in scripts and automations. This makes it possible to adjust your condition and action based on the information of the trigger.

The trigger data made is available during template rendering as the trigger variable.

{% raw %}

# Example configuration.yaml entries
automation:
  trigger:
    platform: state
    entity_id: device_tracker.paulus
  action:
    service: notify.notify
    data_template:
      message: >
        Paulus just changed from {{ trigger.from_state.state }}
        to {{ trigger.to_state.state }}

automation 2:
  trigger:
    platform: mqtt
    topic: /notify/+
  action:
    service_template: >
      notify.{{ trigger.topic.split('/')[-1] }}
    data_template:
      message: '{{ trigger.payload }}'
      
automation 3:
  trigger:
    # Multiple Entities for which you want to perform the same action.
    - platform: state
      entity_id:
        - light.bedroom_closet
      to: 'on'
      # Trigger when someone leaves the closet light on for 10 minutes.
      for: '00:10:00'
    - platform: state
      entity_id:
        - light.kiddos_closet
      to: 'on'
      for: '00:10:00'
    - platform: state
      entity_id:
        - light.linen_closet
      to: 'on'
      for: '00:10:00'
  action:
    - service: light.turn_off
      data_template:
        # Whichever entity triggers the automation we want to turn off THAT entity, not the others.
        entity_id: "{{ trigger.entity_id }}"

{% endraw %}

Important Template Rules

There are a few very important rules to remember when writing automation templates:

1. You must use data_template in place of data when using templates in the data section of a service call.
2. You must use service_template in place of service when using templates in the service section of a service call.
3. You must surround single-line templates with double quotes (") or single quotes (').
4. It is advised that you prepare for undefined variables by using if ... is not none or the default filter, or both.
5. It is advised that when comparing numbers, you convert the number(s) to a float or an int by using the respective filter.
6. While the float and int filters do allow a default fallback value if the conversion is unsuccessful, they do not provide the ability to catch undefined variables.

Remembering these simple rules will help save you from many headaches and endless hours of frustration when using automation templates.

Trigger State Object

Knowing how to access the state object of a trigger entity could be one of the more common questions. Here are a few ways for the state, numeric_state and template triggers:

• trigger.from_state will return the previous state object of the entity.
• trigger.to_state will return the new state object that triggered trigger.
• states[trigger.to_state.domain][trigger.to_state.object_id] will return the current state object of the entity.

Available Trigger Data

The following tables show the available trigger data per platform.

event

Template variable	Data
trigger.platform	Hardcoded: event.
trigger.event	Event object that matched.
trigger.event.data	Optional data

mqtt

Template variable	Data
trigger.platform	Hardcoded: mqtt.
trigger.topic	Topic that received payload.
trigger.payload	Payload.
trigger.payload_json	Dictonary of the JSON parsed payload.
trigger.qos	QOS of payload.

numeric_state

Template variable	Data
trigger.platform	Hardcoded: numeric_state
trigger.entity_id	Entity ID that we observe.
trigger.below	The below threshold, if any.
trigger.above	The above threshold, if any.
trigger.from_state	The previous state object of the entity.
trigger.to_state	The new state object that triggered trigger.

state

Template variable	Data
trigger.platform	Hardcoded: state
trigger.entity_id	Entity ID that we observe.
trigger.from_state	The previous state object of the entity.
trigger.to_state	The new state object that triggered trigger.
trigger.for	Timedelta object how long state has been to state, if any.

sun

Template variable	Data
trigger.platform	Hardcoded: sun
trigger.event	The event that just happened: sunset or sunrise.
trigger.offset	Timedelta object with offset to the event, if any.

template

Template variable	Data
trigger.platform	Hardcoded: template
trigger.entity_id	Entity ID that caused change.
trigger.from_state	Previous state object of entity that caused change.
trigger.to_state	New state object of entity that caused template to change.

time

Template variable	Data
trigger.platform	Hardcoded: time
trigger.now	DateTime object that triggered the time trigger.

time pattern

Template variable	Data
trigger.platform	Hardcoded: time_pattern
trigger.now	DateTime object that triggered the time_pattern trigger.

webhook

Template variable	Data
trigger.platform	Hardcoded: webhook
trigger.webhook_id	The webhook ID that was triggered.
trigger.json	The JSON data of the request (if it had a JSON content type).
trigger.data	The form data of the request (if it had a form data content type).

zone

Template variable	Data
trigger.platform	Hardcoded: zone
trigger.entity_id	Entity ID that we are observing.
trigger.from_state	Previous state object of the entity.
trigger.to_state	New state object of the entity.
trigger.zone	State object of zone
trigger.event	Event that trigger observed: enter or leave.