Script Syntax


Scripts are a sequence of actions that Home Assistant will execute. Scripts are available as an entity through the standalone Script component but can also be embedded in automations and Alexa/Amazon Echo configurations.

When the script is executed within an automation the trigger variable is available. See Available-Trigger-Data.

The script syntax basic structure is a list of key/value maps that contain actions. If a script contains only 1 action, the wrapping list can be omitted.

All actions support an optional alias.

# Example script integration containing script syntax
script:
  example_script:
    sequence:
      # This is written using the Script Syntax
      - alias: "Turn on ceiling light"
        service: light.turn_on
        target:
          entity_id: light.ceiling
      - alias: "Notify that ceiling light is turned on"
        service: notify.notify
        data:
          message: "Turned on the ceiling light!"

Call a Service

The most important one is the action to call a service. This can be done in various ways. For all the different possibilities, have a look at the service calls page.

- alias: "Bedroom lights on"
  service: light.turn_on
  target:
    entity_id: group.bedroom
  data:
    brightness: 100

Activate a Scene

Scripts may also use a shortcut syntax for activating scenes instead of calling the scene.turn_on service.

- scene: scene.morning_living_room

Variables

The variables action allows you to set/override variables that will be accessible by templates in actions after it. See also script variables for how to define variables accessible in the entire script.

- alias: "Set variables"
  variables:
    entities: 
      - light.kitchen
      - light.living_room
    brightness: 100
- alias: "Control lights"
  service: light.turn_on
  target:
    entity_id: "{{ entities }}"
  data:
    brightness: "{{ brightness }}"

Scope of Variables

Variables have local scope. This means that if a variable is changed in a nested sequence block, that change will not be visible in an outer sequence block.

The following example will always say “There are 0 people home”. Inside the choose sequence the variables action will only alter the people variable for that sequence.

sequence:
  # Set the people variable to a default value
  - variables:
      people: 0
  # Try to increment people if Paulus is home
  - choose:
    - conditions:
        - condition: state
          entity_id: device_tracker.paulus
          state: "home"
      sequence:
        # At this scope and this point of the sequence, people == 0
        - variables:
            people: "{{ people + 1 }}"
        # At this scope, people will now be 1 ...
  # ... but at this scope it will still be 0
  # Announce the count of people home
  - service: notify.notify
    data:
      message: "There are {{ people }} people home"

Test a Condition

While executing a script you can add a condition in the main sequence to stop further execution. When a condition does not return true, the script will stop executing. There are many different conditions which are documented at the conditions page.

The condition action only stops executing the current sequence block. When it is used inside a repeat action, only the current iteration of the repeat loop will stop. When it is used inside a choose action, only the actions within that choose will stop.

# If paulus is home, continue to execute the script below these lines
- alias: "Check if Paulus is home"
  condition: state
  entity_id: device_tracker.paulus
  state: "home"

Delay

Delays are useful for temporarily suspending your script and start it at a later moment. We support different syntaxes for a delay as shown below.

# Seconds
# Waits 5 seconds
- alias: "Wait 5s"
  delay: 5
# HH:MM
# Waits 1 hour
- delay: "01:00"
# HH:MM:SS
# Waits 1.5 minutes
- delay: "00:01:30"
# Supports milliseconds, seconds, minutes, hours, days
# Can be used in combination, at least one required
# Waits 1 minute
- delay:
    minutes: 1

All forms accept templates.

# Waits however many minutes input_number.minute_delay is set to
- delay: "{{ states('input_number.minute_delay') | multiply(60) | int }}"

Wait

These actions allow a script to wait for entities in the system to be in a certain state as specified by a template, or some event to happen as expressed by one or more triggers.

Wait Template

This action evaluates the template, and if true, the script will continue. If not, then it will wait until it is true.

The template is re-evaluated whenever an entity ID that it references changes state. If you use non-deterministic functions like now() in the template it will not be continuously re-evaluated, but only when an entity ID that is referenced is changed. If you need to periodically re-evaluate the template, reference a sensor from the Time and Date component that will update minutely or daily.


# Wait until media player is stopped
- alias: "Wait until media player is stopped"
  wait_template: "{{ is_state('media_player.floor', 'stop') }}"

Wait for Trigger

This action can use the same triggers that are available in an automation’s trigger section. See Automation Trigger. The script will continue whenever any of the triggers fires. All previously defined trigger variables, variables and script variables are passed to the trigger.

# Wait for a custom event or light to turn on and stay on for 10 sec
- alias: "Wait for MY_EVENT or light on"
  wait_for_trigger:
    - platform: event
      event_type: MY_EVENT
    - platform: state
      entity_id: light.LIGHT
      to: "on"
      for: 10

Wait Timeout

With both types of waits it is possible to set a timeout after which the script will continue its execution if the condition/event is not satisfied. Timeout has the same syntax as delay, and like delay, also accepts templates.

# Wait for sensor to change to 'on' up to 1 minute before continuing to execute.
- wait_template: "{{ is_state('binary_sensor.entrance', 'on') }}"
  timeout: "00:01:00"

You can also get the script to abort after the timeout by using optional continue_on_timeout: false.


# Wait for IFTTT event or abort after specified timeout.
- wait_for_trigger:
    - platform: event
      event_type: ifttt_webhook_received
      event_data:
        action: connected_to_network
  timeout:
    minutes: "{{ timeout_minutes }}"
  continue_on_timeout: false

Without continue_on_timeout: false the script will always continue since the default for continue_on_timeout is true.

Wait Variable

After each time a wait completes, either because the condition was met, the event happened, or the timeout expired, the variable wait will be created/updated to indicate the result.

Variable Description
wait.completed Exists only after wait_template. true if the condition was met, false otherwise
wait.trigger Exists only after wait_for_trigger. Contains information about which trigger fired. (See Available-Trigger-Data.) Will be none if no trigger happened before timeout expired
wait.remaining Timeout remaining, or none if a timeout was not specified

This can be used to take different actions based on whether or not the condition was met, or to use more than one wait sequentially while implementing a single timeout overall.

# Take different actions depending on if condition was met.
- wait_template: "{{ is_state('binary_sensor.door', 'on') }}"
  timeout: 10
- choose:
    - conditions: "{{ not wait.completed }}"
      sequence:
        - service: script.door_did_not_open
  default:
    - service: script.turn_on
      target:
        entity_id:
          - script.door_did_open
          - script.play_fanfare

# Wait a total of 10 seconds.
- wait_template: "{{ is_state('binary_sensor.door_1', 'on') }}"
  timeout: 10
  continue_on_timeout: false
- service: switch.turn_on
  target:
    entity_id: switch.some_light
- wait_for_trigger:
    - platform: state
      entity_id: binary_sensor.door_2
      to: "on"
      for: 2
  timeout: "{{ wait.remaining }}"
  continue_on_timeout: false
- service: switch.turn_off
  target:
    entity_id: switch.some_light

Fire an Event

This action allows you to fire an event. Events can be used for many things. It could trigger an automation or indicate to another integration that something is happening. For instance, in the below example it is used to create an entry in the logbook.

- alias: "Fire LOGBOOK_ENTRY event"
  event: LOGBOOK_ENTRY
  event_data:
    name: Paulus
    message: is waking up
    entity_id: device_tracker.paulus
    domain: light

You can also use event_data to fire an event with custom data. This could be used to pass data to another script awaiting an event trigger.

The event_data accepts templates.

- event: MY_EVENT
  event_data:
    name: myEvent
    customData: "{{ myCustomVariable }}"

Raise and Consume Custom Events

The following automation example shows how to raise a custom event called event_light_state_changed with entity_id as the event data. The action part could be inside a script or an automation.

- alias: "Fire Event"
  trigger:
    - platform: state
      entity_id: switch.kitchen
      to: "on"
  action:
    - event: event_light_state_changed
      event_data:
        state: "on"

The following automation example shows how to capture the custom event event_light_state_changed with an Event Automation Trigger, and retrieve corresponding entity_id that was passed as the event trigger data, see Available-Trigger-Data for more details.

- alias: "Capture Event"
  trigger:
    - platform: event
      event_type: event_light_state_changed
  action:
    - service: notify.notify
      data:
        message: "kitchen light is turned {{ trigger.event.data.state }}"

Repeat a Group of Actions

This action allows you to repeat a sequence of other actions. Nesting is fully supported. There are three ways to control how many times the sequence will be run.

Counted Repeat

This form accepts a count value. The value may be specified by a template, in which case the template is rendered when the repeat step is reached.

script:
  flash_light:
    mode: restart
    sequence:
      - service: light.turn_on
        target:
          entity_id: "light.{{ light }}"
      - alias: "Cycle light 'count' times"
        repeat:
          count: "{{ count|int * 2 - 1 }}"
          sequence:
            - delay: 2
            - service: light.toggle
              target:
                entity_id: "light.{{ light }}"
  flash_hallway_light:
    sequence:
      - alias: "Flash hallway light 3 times"
        service: script.flash_light
        data:
          light: hallway
          count: 3

While Loop

This form accepts a list of conditions (see conditions page for available options) that are evaluated before each time the sequence is run. The sequence will be run as long as the condition(s) evaluate to true.

script:
  do_something:
    sequence:
      - service: script.get_ready_for_something
      - alias: "Repeat the sequence AS LONG AS the conditions are true"
        repeat:
          while:
            - condition: state
              entity_id: input_boolean.do_something
              state: "on"
            # Don't do it too many times
            - condition: template
              value_template: "{{ repeat.index <= 20 }}"
          sequence:
            - service: script.something

The while also accepts a shorthand notation of a template condition. For example:

- repeat:
    while: "{{ is_state('sensor.mode', 'Home') and repeat.index < 10 }}"
    sequence:
    - ...

Repeat Until

This form accepts a list of conditions that are evaluated after each time the sequence is run. Therefore the sequence will always run at least once. The sequence will be run until the condition(s) evaluate to true.

automation:
  - trigger:
      - platform: state
        entity_id: binary_sensor.xyz
        to: "on"
    condition:
      - condition: state
        entity_id: binary_sensor.something
        state: "off"
    mode: single
    action:
      - alias: "Repeat the sequence UNTIL the conditions are true"
        repeat:
          sequence:
            # Run command that for some reason doesn't always work
            - service: shell_command.turn_something_on
            # Give it time to complete
            - delay:
                milliseconds: 200
          until:
            # Did it work?
            - condition: state
              entity_id: binary_sensor.something
              state: "on"

until also accepts a shorthand notation of a template condition. For example:

- repeat:
    until: "{{ is_state('device_tracker.iphone', 'home') }}"
    sequence:
    - ...

Repeat Loop Variable

A variable named repeat is defined within the repeat action (i.e., it is available inside sequence, while & until.) It contains the following fields:

field description
first True during the first iteration of the repeat sequence
index The iteration number of the loop: 1, 2, 3, …
last True during the last iteration of the repeat sequence, which is only valid for counted loops

Choose a Group of Actions

This action allows you to select a sequence of other actions from a list of sequences. Nesting is fully supported.

Each sequence is paired with a list of conditions. (See the conditions page for available options and how multiple conditions are handled.) The first sequence whose conditions are all true will be run. An optional default sequence can be included which will be run only if none of the sequences from the list are run.

An optional alias can be added to each of the sequences, excluding the default sequence.

The choose action can be used like an “if” statement. The first conditions/sequence pair is like the “if/then”, and can be used just by itself. Or additional pairs can be added, each of which is like an “elif/then”. And lastly, a default can be added, which would be like the “else.”

# Example with just an "if"
automation:
  - trigger:
      - platform: state
        entity_id: binary_sensor.motion
        to: "on"
    action:
      - choose:
          - alias: "IF nobody home, sound the alarm!"
            conditions:
              - condition: state
                entity_id: group.family
                state: not_home
            sequence:
              - service: script.siren
                data:
                  duration: 60
      - service: light.turn_on
        target:
          entity_id: all
# Example with "if" and "else"
automation:
  - trigger:
      - platform: state
        entity_id: binary_sensor.motion
    mode: queued
    action:
      - alias: "Turn on front lights if motion detected, else turn off"
        choose:
          # IF motion detected
          - alias: "Motion detected"
            conditions: "{{ trigger.to_state.state == 'on' }}"
            sequence:
              - service: script.turn_on
                target:
                  entity_id:
                    - script.slowly_turn_on_front_lights
                    - script.announce_someone_at_door
        # ELSE (i.e., motion stopped)
        default:
          - service: light.turn_off
            target:
              entity_id: light.front_lights
# Example with "if", "elif" and "else"
automation:
  - trigger:
      - platform: state
        entity_id: input_boolean.simulate
        to: "on"
    mode: restart
    action:
      - choose:
          # IF morning
          - conditions:
              - condition: template
                value_template: "{{ now().hour < 9 }}"
            sequence:
              - service: script.sim_morning
          # ELIF day
          - conditions:
              - condition: template
                value_template: "{{ now().hour < 18 }}"
            sequence:
              - service: light.turn_off
                target:
                  entity_id: light.living_room
              - service: script.sim_day
        # ELSE night
        default:
          - service: light.turn_off
            target:
              entity_id: light.kitchen
          - delay:
              minutes: "{{ range(1, 11)|random }}"
          - service: light.turn_off
            target:
              entity_id: all

conditions also accepts a shorthand notation of a template condition. For example:

automation:
  - trigger:
      - platform: state
        entity_id: input_select.home_mode
    action:
      - choose:
          - conditions: >
              {{ trigger.to_state.state == 'Home' and
                 is_state('binary_sensor.all_clear', 'on') }}
            sequence:
              - service: script.arrive_home
                data:
                  ok: true
          - conditions: >
              {{ trigger.to_state.state == 'Home' and
                 is_state('binary_sensor.all_clear', 'off') }}
            sequence:
              - service: script.turn_on
                target:
                  entity_id: script.flash_lights
              - service: script.arrive_home
                data:
                  ok: false
          - conditions: "{{ trigger.to_state.state == 'Away' }}"
            sequence:
              - service: script.left_home

More choose can be used together. This is the case of an IF-IF.

The following example shows how a single automation can control entities that aren’t related to each other but have in common the same trigger.

When the sun goes below the horizon, the porch and garden lights must turn on. If someone is watching the TV in the living room, there is a high chance that someone is in that room, therefore the living room lights have to turn on too. The same concept applies to the studio room.

# Example with "if" and "if"
automation:
  - alias: "Turn lights on when the sun gets dim and if some room is occupied"
      trigger:
        - platform: numeric_state
          entity_id: sun.sun
          attribute: elevation
          below: 4
      action:
        # This must always apply
        - service: light.turn_on
          data:
            brightness: 255
            color_temp: 366
          target:
            entity_id:
              - light.porch
              - light.garden
        # IF a entity is ON
        - choose:
            - conditions:
                - condition: state
                  entity_id: binary_sensor.livingroom_tv
                  state: "on"
              sequence:
                - service: light.turn_on
                  data:
                    brightness: 255
                    color_temp: 366
                  target:
                    entity_id: light.livingroom
         # IF another entity not related to the previous, is ON
        - choose:
            - conditions:
                - condition: state
                  entity_id: binary_sensor.studio_pc
                  state: "on"
              sequence:
                - service: light.turn_on
                  data:
                    brightness: 255
                    color_temp: 366
                  target:
                    entity_id: light.studio