Call a function periodically from a component

cagabi · July 3, 2019, 2:20pm

Hi,

I need to call the same function every minute from inside my component.

I want to do it using the event loop so was thinking of using async_create_task and in my function check if enough time has passed. But this doesn’t feel right and that’s why the question: is there a way to periodically call a function from a component?

andrewdolphin · July 3, 2019, 3:14pm

Check async_track_time_interval.

github.com

home-assistant/core/blob/eec67d8b1a3b25276a1dc0b2eb3449571ae71284/homeassistant/helpers/event.py

"""Helpers for listening to events."""
from datetime import timedelta
import functools as ft
from typing import Callable

import attr

from homeassistant.loader import bind_hass
from homeassistant.helpers.sun import get_astral_event_next
from homeassistant.core import HomeAssistant, callback
from homeassistant.const import (
    ATTR_NOW, EVENT_STATE_CHANGED, EVENT_TIME_CHANGED, MATCH_ALL,
    SUN_EVENT_SUNRISE, SUN_EVENT_SUNSET, EVENT_CORE_CONFIG_UPDATE)
from homeassistant.util import dt as dt_util
from homeassistant.util.async_ import run_callback_threadsafe

# PyLint does not like the use of threaded_listener_factory
# pylint: disable=invalid-name

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cagabi · July 3, 2019, 3:31pm

Thank you, I’ll have a look

cagabi · July 3, 2019, 4:41pm

I am trying the async_track_time_interval with this simple line

hass.helpers.event.async_track_time_interval(_LOGGER.debug("triggered"), datetime.timedelta(seconds=2))

The _LOGGER is run once and after I get this error every 2 seconds

Traceback (most recent call last):
  File "/usr/lib/python3.6/concurrent/futures/thread.py", line 56, in run
    result = self.fn(*self.args, **self.kwargs)
TypeError: 'NoneType' object is not callable

Am I passing the action right?

cagabi · July 5, 2019, 12:42pm

I was doing 2 things wrong, first not passing the hass object and second passing arguments with my function.