core/homeassistant/components/temper/sensor.py

105 lines
3.2 KiB
Python

"""Support for getting temperature from TEMPer devices."""
import logging
import voluptuous as vol
from homeassistant.components.sensor import PLATFORM_SCHEMA
from homeassistant.const import CONF_NAME, DEVICE_DEFAULT_NAME, TEMP_FAHRENHEIT
from homeassistant.helpers.entity import Entity
_LOGGER = logging.getLogger(__name__)
CONF_SCALE = 'scale'
CONF_OFFSET = 'offset'
PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend({
vol.Optional(CONF_NAME, default=DEVICE_DEFAULT_NAME): vol.Coerce(str),
vol.Optional(CONF_SCALE, default=1): vol.Coerce(float),
vol.Optional(CONF_OFFSET, default=0): vol.Coerce(float)
})
TEMPER_SENSORS = []
def get_temper_devices():
"""Scan the Temper devices from temperusb."""
from temperusb.temper import TemperHandler
return TemperHandler().get_devices()
def setup_platform(hass, config, add_entities, discovery_info=None):
"""Set up the Temper sensors."""
temp_unit = hass.config.units.temperature_unit
name = config.get(CONF_NAME)
scaling = {
'scale': config.get(CONF_SCALE),
'offset': config.get(CONF_OFFSET)
}
temper_devices = get_temper_devices()
for idx, dev in enumerate(temper_devices):
if idx != 0:
name = name + '_' + str(idx)
TEMPER_SENSORS.append(TemperSensor(dev, temp_unit, name, scaling))
add_entities(TEMPER_SENSORS)
def reset_devices():
"""
Re-scan for underlying Temper sensors and assign them to our devices.
This assumes the same sensor devices are present in the same order.
"""
temper_devices = get_temper_devices()
for sensor, device in zip(TEMPER_SENSORS, temper_devices):
sensor.set_temper_device(device)
class TemperSensor(Entity):
"""Representation of a Temper temperature sensor."""
def __init__(self, temper_device, temp_unit, name, scaling):
"""Initialize the sensor."""
self.temp_unit = temp_unit
self.scale = scaling['scale']
self.offset = scaling['offset']
self.current_value = None
self._name = name
self.set_temper_device(temper_device)
@property
def name(self):
"""Return the name of the temperature sensor."""
return self._name
@property
def state(self):
"""Return the state of the entity."""
return self.current_value
@property
def unit_of_measurement(self):
"""Return the unit of measurement of this entity, if any."""
return self.temp_unit
def set_temper_device(self, temper_device):
"""Assign the underlying device for this sensor."""
self.temper_device = temper_device
# set calibration data
self.temper_device.set_calibration_data(
scale=self.scale,
offset=self.offset
)
def update(self):
"""Retrieve latest state."""
try:
format_str = ('fahrenheit' if self.temp_unit == TEMP_FAHRENHEIT
else 'celsius')
sensor_value = self.temper_device.get_temperature(format_str)
self.current_value = round(sensor_value, 1)
except IOError:
_LOGGER.error("Failed to get temperature. The device address may"
"have changed. Attempting to reset device")
reset_devices()