core/homeassistant/components/sensor/arwn.py

129 lines
3.8 KiB
Python

"""
Support for collecting data from the ARWN project.
For more details about this platform, please refer to the documentation at
https://home-assistant.io/components/sensor.arwn/
"""
import json
import logging
import homeassistant.components.mqtt as mqtt
from homeassistant.const import (TEMP_FAHRENHEIT, TEMP_CELSIUS)
from homeassistant.helpers.entity import Entity
from homeassistant.util import slugify
_LOGGER = logging.getLogger(__name__)
DEPENDENCIES = ['mqtt']
DOMAIN = 'arwn'
SENSORS = {}
TOPIC = 'arwn/#'
def discover_sensors(topic, payload):
"""Given a topic, dynamically create the right sensor type."""
parts = topic.split('/')
unit = payload.get('units', '')
domain = parts[1]
if domain == 'temperature':
name = parts[2]
if unit == 'F':
unit = TEMP_FAHRENHEIT
else:
unit = TEMP_CELSIUS
return ArwnSensor(name, 'temp', unit)
if domain == 'barometer':
return ArwnSensor('Barometer', 'pressure', unit)
if domain == 'wind':
return (ArwnSensor('Wind Speed', 'speed', unit),
ArwnSensor('Wind Gust', 'gust', unit),
ArwnSensor('Wind Direction', 'direction', '°'))
def _slug(name):
return 'sensor.arwn_{}'.format(slugify(name))
def setup_platform(hass, config, add_devices, discovery_info=None):
"""Set up the ARWN platform."""
def sensor_event_received(topic, payload, qos):
"""Process events as sensors.
When a new event on our topic (arwn/#) is received we map it
into a known kind of sensor based on topic name. If we've
never seen this before, we keep this sensor around in a global
cache. If we have seen it before, we update the values of the
existing sensor. Either way, we push an ha state update at the
end for the new event we've seen.
This lets us dynamically incorporate sensors without any
configuration on our side.
"""
event = json.loads(payload)
sensors = discover_sensors(topic, event)
if not sensors:
return
if 'timestamp' in event:
del event['timestamp']
for sensor in sensors:
if sensor.name not in SENSORS:
sensor.hass = hass
sensor.set_event(event)
SENSORS[sensor.name] = sensor
_LOGGER.debug("Registering new sensor %(name)s => %(event)s",
dict(name=sensor.name, event=event))
add_devices((sensor,))
else:
SENSORS[sensor.name].set_event(event)
SENSORS[sensor.name].update_ha_state()
mqtt.subscribe(hass, TOPIC, sensor_event_received, 0)
return True
class ArwnSensor(Entity):
"""Representation of an ARWN sensor."""
def __init__(self, name, state_key, units):
"""Initialize the sensor."""
self.hass = None
self.entity_id = _slug(name)
self._name = name
self._state_key = state_key
self.event = {}
self._unit_of_measurement = units
def set_event(self, event):
"""Update the sensor with the most recent event."""
self.event = {}
self.event.update(event)
@property
def state(self):
"""Return the state of the device."""
return self.event.get(self._state_key, None)
@property
def name(self):
"""Get the name of the sensor."""
return self._name
@property
def state_attributes(self):
"""Return all the state attributes."""
return self.event
@property
def unit_of_measurement(self):
"""Unit this state is expressed in."""
return self._unit_of_measurement
@property
def should_poll(self):
"""Should we poll."""
return False