core/homeassistant/components/automation/template.py

54 lines
1.6 KiB
Python

"""
Offer template automation rules.
For more details about this automation rule, please refer to the documentation
at https://home-assistant.io/components/automation/#template-trigger
"""
import logging
import voluptuous as vol
from homeassistant.const import (
CONF_VALUE_TEMPLATE, CONF_PLATFORM, MATCH_ALL)
from homeassistant.helpers import condition
from homeassistant.helpers.event import track_state_change
import homeassistant.helpers.config_validation as cv
_LOGGER = logging.getLogger(__name__)
TRIGGER_SCHEMA = IF_ACTION_SCHEMA = vol.Schema({
vol.Required(CONF_PLATFORM): 'template',
vol.Required(CONF_VALUE_TEMPLATE): cv.template,
})
def trigger(hass, config, action):
"""Listen for state changes based on configuration."""
value_template = config.get(CONF_VALUE_TEMPLATE)
# Local variable to keep track of if the action has already been triggered
already_triggered = False
def state_changed_listener(entity_id, from_s, to_s):
"""Listen for state changes and calls action."""
nonlocal already_triggered
template_result = condition.template(hass, value_template)
# Check to see if template returns true
if template_result and not already_triggered:
already_triggered = True
action({
'trigger': {
'platform': 'template',
'entity_id': entity_id,
'from_state': from_s,
'to_state': to_s,
},
})
elif not template_result:
already_triggered = False
track_state_change(hass, MATCH_ALL, state_changed_listener)
return True