core/homeassistant/components/sensor/mqtt.py

230 lines
8.6 KiB
Python

"""
Support for MQTT sensors.
For more details about this platform, please refer to the documentation at
https://home-assistant.io/components/sensor.mqtt/
"""
import logging
import json
from datetime import timedelta
from typing import Optional
import voluptuous as vol
from homeassistant.core import callback
from homeassistant.components import sensor
from homeassistant.components.mqtt import (
ATTR_DISCOVERY_HASH, CONF_AVAILABILITY_TOPIC, CONF_STATE_TOPIC,
CONF_PAYLOAD_AVAILABLE, CONF_PAYLOAD_NOT_AVAILABLE, CONF_QOS,
MqttAvailability, MqttDiscoveryUpdate, MqttEntityDeviceInfo)
from homeassistant.components.mqtt.discovery import MQTT_DISCOVERY_NEW
from homeassistant.components.sensor import DEVICE_CLASSES_SCHEMA
from homeassistant.const import (
CONF_FORCE_UPDATE, CONF_NAME, CONF_VALUE_TEMPLATE, STATE_UNKNOWN,
CONF_UNIT_OF_MEASUREMENT, CONF_ICON, CONF_DEVICE_CLASS, CONF_DEVICE)
from homeassistant.helpers.entity import Entity
from homeassistant.components import mqtt
import homeassistant.helpers.config_validation as cv
from homeassistant.helpers.typing import HomeAssistantType, ConfigType
from homeassistant.helpers.dispatcher import async_dispatcher_connect
from homeassistant.helpers.event import async_track_point_in_utc_time
from homeassistant.util import dt as dt_util
_LOGGER = logging.getLogger(__name__)
CONF_EXPIRE_AFTER = 'expire_after'
CONF_JSON_ATTRS = 'json_attributes'
CONF_UNIQUE_ID = 'unique_id'
DEFAULT_NAME = 'MQTT 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,
vol.Optional(CONF_ICON): cv.icon,
vol.Optional(CONF_DEVICE_CLASS): DEVICE_CLASSES_SCHEMA,
vol.Optional(CONF_JSON_ATTRS, default=[]): cv.ensure_list_csv,
vol.Optional(CONF_EXPIRE_AFTER): cv.positive_int,
vol.Optional(CONF_FORCE_UPDATE, default=DEFAULT_FORCE_UPDATE): cv.boolean,
# Integrations shouldn't never expose unique_id through configuration
# this here is an exception because MQTT is a msg transport, not a protocol
vol.Optional(CONF_UNIQUE_ID): cv.string,
vol.Optional(CONF_DEVICE): mqtt.MQTT_ENTITY_DEVICE_INFO_SCHEMA,
}).extend(mqtt.MQTT_AVAILABILITY_SCHEMA.schema)
async def async_setup_platform(hass: HomeAssistantType, config: ConfigType,
async_add_entities, discovery_info=None):
"""Set up MQTT sensors through configuration.yaml."""
await _async_setup_entity(hass, config, async_add_entities)
async def async_setup_entry(hass, config_entry, async_add_entities):
"""Set up MQTT sensors dynamically through MQTT discovery."""
async def async_discover_sensor(discovery_payload):
"""Discover and add a discovered MQTT sensor."""
config = PLATFORM_SCHEMA(discovery_payload)
await _async_setup_entity(hass, config, async_add_entities,
discovery_payload[ATTR_DISCOVERY_HASH])
async_dispatcher_connect(hass,
MQTT_DISCOVERY_NEW.format(sensor.DOMAIN, 'mqtt'),
async_discover_sensor)
async def _async_setup_entity(hass: HomeAssistantType, config: ConfigType,
async_add_entities, discovery_hash=None):
"""Set up MQTT sensor."""
value_template = config.get(CONF_VALUE_TEMPLATE)
if value_template is not None:
value_template.hass = hass
async_add_entities([MqttSensor(
config.get(CONF_NAME),
config.get(CONF_STATE_TOPIC),
config.get(CONF_QOS),
config.get(CONF_UNIT_OF_MEASUREMENT),
config.get(CONF_FORCE_UPDATE),
config.get(CONF_EXPIRE_AFTER),
config.get(CONF_ICON),
config.get(CONF_DEVICE_CLASS),
value_template,
config.get(CONF_JSON_ATTRS),
config.get(CONF_UNIQUE_ID),
config.get(CONF_AVAILABILITY_TOPIC),
config.get(CONF_PAYLOAD_AVAILABLE),
config.get(CONF_PAYLOAD_NOT_AVAILABLE),
config.get(CONF_DEVICE),
discovery_hash,
)])
class MqttSensor(MqttAvailability, MqttDiscoveryUpdate, MqttEntityDeviceInfo,
Entity):
"""Representation of a sensor that can be updated using MQTT."""
def __init__(self, name, state_topic, qos, unit_of_measurement,
force_update, expire_after, icon, device_class: Optional[str],
value_template, json_attributes, unique_id: Optional[str],
availability_topic, payload_available, payload_not_available,
device_config: Optional[ConfigType], discovery_hash):
"""Initialize the sensor."""
MqttAvailability.__init__(self, availability_topic, qos,
payload_available, payload_not_available)
MqttDiscoveryUpdate.__init__(self, discovery_hash)
MqttEntityDeviceInfo.__init__(self, device_config)
self._state = STATE_UNKNOWN
self._name = name
self._state_topic = state_topic
self._qos = qos
self._unit_of_measurement = unit_of_measurement
self._force_update = force_update
self._template = value_template
self._expire_after = expire_after
self._icon = icon
self._device_class = device_class
self._expiration_trigger = None
self._json_attributes = set(json_attributes)
self._unique_id = unique_id
self._attributes = None
self._discovery_hash = discovery_hash
async def async_added_to_hass(self):
"""Subscribe to MQTT events."""
await MqttAvailability.async_added_to_hass(self)
await MqttDiscoveryUpdate.async_added_to_hass(self)
@callback
def message_received(topic, payload, qos):
"""Handle new MQTT messages."""
# auto-expire enabled?
if self._expire_after is not None and self._expire_after > 0:
# Reset old trigger
if self._expiration_trigger:
self._expiration_trigger()
self._expiration_trigger = None
# Set new trigger
expiration_at = (
dt_util.utcnow() + timedelta(seconds=self._expire_after))
self._expiration_trigger = async_track_point_in_utc_time(
self.hass, self.value_is_expired, expiration_at)
if self._json_attributes:
self._attributes = {}
try:
json_dict = json.loads(payload)
if isinstance(json_dict, dict):
attrs = {k: json_dict[k] for k in
self._json_attributes & json_dict.keys()}
self._attributes = attrs
else:
_LOGGER.warning("JSON result was not a dictionary")
except ValueError:
_LOGGER.warning("MQTT payload could not be parsed as JSON")
_LOGGER.debug("Erroneous JSON: %s", payload)
if self._template is not None:
payload = self._template.async_render_with_possible_json_value(
payload, self._state)
self._state = payload
self.async_schedule_update_ha_state()
await mqtt.async_subscribe(self.hass, self._state_topic,
message_received, self._qos)
@callback
def value_is_expired(self, *_):
"""Triggered when value is expired."""
self._expiration_trigger = None
self._state = STATE_UNKNOWN
self.async_schedule_update_ha_state()
@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 force_update(self):
"""Force update."""
return self._force_update
@property
def state(self):
"""Return the state of the entity."""
return self._state
@property
def device_state_attributes(self):
"""Return the state attributes."""
return self._attributes
@property
def unique_id(self):
"""Return a unique ID."""
return self._unique_id
@property
def icon(self):
"""Return the icon."""
return self._icon
@property
def device_class(self) -> Optional[str]:
"""Return the device class of the sensor."""
return self._device_class