Source code for caspia.node.components.sensors.sht2x

import arrow

from .base import SensorBase
from .datatypes import parse_humidity, parse_temperature


class SHT2XSensor(SensorBase):
    type = 0x08

    class MeasurementEvent(SensorBase.MeasurementEvent):
        def parse(self):
            super().parse()
            self.temperature = self.measurement_data[0]
            self.humidity = self.measurement_data[1]
            self.error = any(m is None for m in self.measurement_data)

        def __repr_fields__(self):
            time = self.timestamp.format() if self.timestamp else '-'
            temp = '{:.02f}°C'.format(self.temperature) if not self.error else 'error'
            rh = '{:.02f} %'.format(self.humidity) if not self.error else 'error'
            return dict(time=time, temp=temp, humidity=rh)

    class State(SensorBase.State):
        def __init__(self, temperature=None, humidity=None, error=None, timestamp=None):
            self.temperature = temperature
            self.error = error
            self.humidity = humidity
            self.timestamp = timestamp

        def update_from_bytes(self, data):
            measurement = SHT2XSensor.parse_measurement_data(data)
            self.temperature = measurement[0]
            self.humidity = measurement[1]
            self.error = any(m is None for m in measurement)
            self.timestamp = arrow.now()

        def update_from_event(self, event):
            if isinstance(event, SHT2XSensor.MeasurementEvent):
                self.temperature = event.temperature
                self.humidity = event.humidity
                self.error = event.error
                self.timestamp = event.timestamp

        def __repr_fields__(self):
            return dict(temp=self.temperature,
                        humidity=self.humidity,
                        timestamp=self.timestamp,
                        error=self.error)

    class Config(SensorBase.Config):
        pass

    @classmethod
    def parse_measurement_data(cls, data):
        return parse_temperature(data[0:2]), parse_humidity(data[2:4])