Home Assistant and The Things Network (TTN)

"""Relay MQTT messages from The Things Network to a local MQTT broker."""
import paho.mqtt.client as mqtt
import paho.mqtt.publish as publish

DEVICE_NAME = '<DeviceID>'

TTN_BROKER = '<Region>.thethings.network'
TTN_USERNAME = '<AppID>'
TTN_PASSWORD = '<AppKey>'
TTN_TOPIC = '+/devices/{}/up'.format(DEVICE_NAME)

LOCAL_BROKER = '192.168.0.2'
LOCAL_TOPIC = 'home/ttn/garden_temp'


def on_connect(client, userdata, flags, rc):
    """Subscribe to topic after connection to broker is made."""
    print("Connected with result code", str(rc))
    client.subscribe(TTN_TOPIC)


def on_message(client, userdata, msg):
    """Relay message to a different broker."""
    publish.single(
        LOCAL_TOPIC, payload=msg.payload, qos=0, retain=False,
        hostname=LOCAL_BROKER, port=1883, client_id='ttn-local',
        keepalive=60, will=None, auth=None, tls=None, protocol=mqtt.MQTTv311)


client = mqtt.Client()
client.username_pw_set(TTN_USERNAME, password=TTN_PASSWORD)
client.on_connect = on_connect
client.on_message = on_message
client.connect(TTN_BROKER, 1883, 60)

client.loop_forever()

"""Support for The Things Network MQTT sensors."""
import asyncio
from datetime import timedelta
import json
import logging

import voluptuous as vol

import homeassistant.components.mqtt as mqtt
from homeassistant.components.mqtt import CONF_STATE_TOPIC
from homeassistant.const import CONF_NAME, CONF_UNIT_OF_MEASUREMENT
from homeassistant.core import callback
import homeassistant.helpers.config_validation as cv
from homeassistant.helpers.entity import Entity

_LOGGER = logging.getLogger(__name__)

DEFAULT_NAME = 'MQTT TTN Sensor'
DEFAULT_FORCE_UPDATE = False
DEPENDENCIES = ['mqtt']

PLATFORM_SCHEMA = mqtt.MQTT_RO_PLATFORM_SCHEMA.extend({
    vol.Optional(CONF_NAME, default=DEFAULT_NAME): cv.string,
    vol.Optional(CONF_UNIT_OF_MEASUREMENT): cv.string,

})


@asyncio.coroutine
def async_setup_platform(hass, config, async_add_devices, discovery_info=None):
    """Set up the TTN MQTT Sensor."""
    async_add_devices([MqttTtnSensor(
        config.get(CONF_NAME), config.get(CONF_STATE_TOPIC),
        config.get(CONF_UNIT_OF_MEASUREMENT))
    ])


class MqttTtnSensor(Entity):
    """Representation of a sensor."""

    def __init__(self, name, state_topic, unit_of_measurement):
        """Initialize the sensor."""
        self._state = None
        self._name = name
        self._unit_of_measurement = unit_of_measurement
        self._attributes = {}
        self._state_topic = state_topic

    def async_added_to_hass(self):
        """Subscribe to MQTT events."""
        @callback
        def message_received(topic, payload, qos):
            """Handle new MQTT messages."""

            try:
                data = json.loads(payload)
            except json.JSONDecodeError:
                _LOGGER.error("Invalid JSON data received: %s", data)

            self._state = data['payload_fields'][next(
                iter(data['payload_fields']))]
            self._attributes = data
            del self._attributes['payload_fields']
            del self._attributes['metadata']
            self.async_schedule_update_ha_state()

        return mqtt.async_subscribe(
            self.hass, self._state_topic, message_received, 0)

    @property
    def should_poll(self):
        """No polling needed."""
        return False

    @property
    def name(self):
        """Return the name of the sensor."""
        return self._name

    @property
    def unit_of_measurement(self):
        """Return the unit this state is expressed in."""
        return self._unit_of_measurement

    @property
    def state_attributes(self):
        """Return the attributes of the entity."""
        return self._attributes

    @property
    def state(self):
        """Return the state of the entity."""
        return self._state