core/homeassistant/components/template/trigger.py

161 lines
4.6 KiB
Python

"""Offer template automation rules."""
import logging
import voluptuous as vol
from homeassistant import exceptions
from homeassistant.components.automation import (
AutomationActionType,
AutomationTriggerInfo,
)
from homeassistant.const import CONF_FOR, CONF_PLATFORM, CONF_VALUE_TEMPLATE
from homeassistant.core import CALLBACK_TYPE, HassJob, HomeAssistant, callback
from homeassistant.helpers import config_validation as cv, template
from homeassistant.helpers.event import (
TrackTemplate,
async_call_later,
async_track_template_result,
)
from homeassistant.helpers.template import Template, result_as_boolean
from homeassistant.helpers.typing import ConfigType
# mypy: allow-untyped-defs, no-check-untyped-defs
_LOGGER = logging.getLogger(__name__)
TRIGGER_SCHEMA = IF_ACTION_SCHEMA = cv.TRIGGER_BASE_SCHEMA.extend(
{
vol.Required(CONF_PLATFORM): "template",
vol.Required(CONF_VALUE_TEMPLATE): cv.template,
vol.Optional(CONF_FOR): cv.positive_time_period_template,
}
)
async def async_attach_trigger(
hass: HomeAssistant,
config: ConfigType,
action: AutomationActionType,
automation_info: AutomationTriggerInfo,
*,
platform_type: str = "template",
) -> CALLBACK_TYPE:
"""Listen for state changes based on configuration."""
trigger_data = automation_info["trigger_data"]
value_template: Template = config[CONF_VALUE_TEMPLATE]
value_template.hass = hass
time_delta = config.get(CONF_FOR)
template.attach(hass, time_delta)
delay_cancel = None
job = HassJob(action)
armed = False
# Arm at setup if the template is already false.
try:
if not result_as_boolean(
value_template.async_render(automation_info["variables"])
):
armed = True
except exceptions.TemplateError as ex:
_LOGGER.warning(
"Error initializing 'template' trigger for '%s': %s",
automation_info["name"],
ex,
)
@callback
def template_listener(event, updates):
"""Listen for state changes and calls action."""
nonlocal delay_cancel, armed
result = updates.pop().result
if isinstance(result, exceptions.TemplateError):
_LOGGER.warning(
"Error evaluating 'template' trigger for '%s': %s",
automation_info["name"],
result,
)
return
if delay_cancel:
# pylint: disable=not-callable
delay_cancel()
delay_cancel = None
if not result_as_boolean(result):
armed = True
return
# Only fire when previously armed.
if not armed:
return
# Fire!
armed = False
entity_id = event and event.data.get("entity_id")
from_s = event and event.data.get("old_state")
to_s = event and event.data.get("new_state")
if entity_id is not None:
description = f"{entity_id} via template"
else:
description = "time change or manual update via template"
template_variables = {
"platform": platform_type,
"entity_id": entity_id,
"from_state": from_s,
"to_state": to_s,
}
trigger_variables = {
**trigger_data,
"for": time_delta,
"description": description,
}
@callback
def call_action(*_):
"""Call action with right context."""
nonlocal trigger_variables
hass.async_run_hass_job(
job,
{"trigger": {**template_variables, **trigger_variables}},
(to_s.context if to_s else None),
)
if not time_delta:
call_action()
return
try:
period = cv.positive_time_period(
template.render_complex(time_delta, {"trigger": template_variables})
)
except (exceptions.TemplateError, vol.Invalid) as ex:
_LOGGER.error(
"Error rendering '%s' for template: %s", automation_info["name"], ex
)
return
trigger_variables["for"] = period
delay_cancel = async_call_later(hass, period.total_seconds(), call_action)
info = async_track_template_result(
hass,
[TrackTemplate(value_template, automation_info["variables"])],
template_listener,
)
unsub = info.async_remove
@callback
def async_remove():
"""Remove state listeners async."""
unsub()
if delay_cancel:
# pylint: disable=not-callable
delay_cancel()
return async_remove