core/homeassistant/components/tradfri/base_class.py

"""Base class for IKEA TRADFRI."""
from functools import wraps
import logging

from pytradfri.error import PytradfriError

from homeassistant.core import callback
from homeassistant.helpers.entity import Entity

from .const import DOMAIN

_LOGGER = logging.getLogger(__name__)


def handle_error(func):
    """Handle tradfri api call error."""

    @wraps(func)
    async def wrapper(command):
        """Decorate api call."""
        try:
            await func(command)
        except PytradfriError as err:
            _LOGGER.error("Unable to execute command %s: %s", command, err)

    return wrapper


class TradfriBaseClass(Entity):
    """Base class for IKEA TRADFRI.

    All devices and groups should ultimately inherit from this class.
    """

    _attr_should_poll = False

    def __init__(self, device, api, gateway_id):
        """Initialize a device."""
        self._api = handle_error(api)
        self._device = None
        self._device_control = None
        self._device_data = None
        self._gateway_id = gateway_id
        self._refresh(device)

    @callback
    def _async_start_observe(self, exc=None):
        """Start observation of device."""
        if exc:
            self.async_write_ha_state()
            _LOGGER.warning("Observation failed for %s", self._attr_name, exc_info=exc)

        try:
            cmd = self._device.observe(
                callback=self._observe_update,
                err_callback=self._async_start_observe,
                duration=0,
            )
            self.hass.async_create_task(self._api(cmd))
        except PytradfriError as err:
            _LOGGER.warning("Observation failed, trying again", exc_info=err)
            self._async_start_observe()

    async def async_added_to_hass(self):
        """Start thread when added to hass."""
        self._async_start_observe()

    @callback
    def _observe_update(self, device):
        """Receive new state data for this device."""
        self._refresh(device)
        self.async_write_ha_state()

    def _refresh(self, device):
        """Refresh the device data."""
        self._device = device
        self._attr_name = device.name


class TradfriBaseDevice(TradfriBaseClass):
    """Base class for a TRADFRI device.

    All devices should inherit from this class.
    """

    @property
    def device_info(self):
        """Return the device info."""
        info = self._device.device_info

        return {
            "identifiers": {(DOMAIN, self._device.id)},
            "manufacturer": info.manufacturer,
            "model": info.model_number,
            "name": self._attr_name,
            "sw_version": info.firmware_version,
            "via_device": (DOMAIN, self._gateway_id),
        }

    def _refresh(self, device):
        """Refresh the device data."""
        super()._refresh(device)
        self._attr_available = device.reachable