core/homeassistant/components/switch/mqtt.py

120 lines
3.8 KiB
Python

"""
Support for MQTT switches.
For more details about this platform, please refer to the documentation at
https://home-assistant.io/components/switch.mqtt/
"""
import logging
import homeassistant.components.mqtt as mqtt
from homeassistant.components.switch import SwitchDevice
from homeassistant.const import CONF_VALUE_TEMPLATE
from homeassistant.helpers import template
_LOGGER = logging.getLogger(__name__)
DEFAULT_NAME = "MQTT Switch"
DEFAULT_QOS = 0
DEFAULT_PAYLOAD_ON = "ON"
DEFAULT_PAYLOAD_OFF = "OFF"
DEFAULT_OPTIMISTIC = False
DEFAULT_RETAIN = False
DEPENDENCIES = ['mqtt']
# pylint: disable=unused-argument
def setup_platform(hass, config, add_devices_callback, discovery_info=None):
"""Add MQTT switch."""
if config.get('command_topic') is None:
_LOGGER.error("Missing required variable: command_topic")
return False
add_devices_callback([MqttSwitch(
hass,
config.get('name', DEFAULT_NAME),
config.get('state_topic'),
config.get('command_topic'),
config.get('qos', DEFAULT_QOS),
config.get('retain', DEFAULT_RETAIN),
config.get('payload_on', DEFAULT_PAYLOAD_ON),
config.get('payload_off', DEFAULT_PAYLOAD_OFF),
config.get('optimistic', DEFAULT_OPTIMISTIC),
config.get(CONF_VALUE_TEMPLATE))])
# pylint: disable=too-many-arguments, too-many-instance-attributes
class MqttSwitch(SwitchDevice):
"""Representation of a switch that can be toggled using MQTT."""
def __init__(self, hass, name, state_topic, command_topic, qos, retain,
payload_on, payload_off, optimistic, value_template):
"""Initialize the MQTT switch."""
self._state = False
self._hass = hass
self._name = name
self._state_topic = state_topic
self._command_topic = command_topic
self._qos = qos
self._retain = retain
self._payload_on = payload_on
self._payload_off = payload_off
self._optimistic = optimistic
def message_received(topic, payload, qos):
"""A new MQTT message has been received."""
if value_template is not None:
payload = template.render_with_possible_json_value(
hass, value_template, payload)
if payload == self._payload_on:
self._state = True
self.update_ha_state()
elif payload == self._payload_off:
self._state = False
self.update_ha_state()
if self._state_topic is None:
# Force into optimistic mode.
self._optimistic = True
else:
mqtt.subscribe(hass, self._state_topic, message_received,
self._qos)
@property
def should_poll(self):
"""No polling needed."""
return False
@property
def name(self):
"""Return the name of the switch."""
return self._name
@property
def is_on(self):
"""Return true if device is on."""
return self._state
@property
def assumed_state(self):
"""Return true if we do optimistic updates."""
return self._optimistic
def turn_on(self, **kwargs):
"""Turn the device on."""
mqtt.publish(self.hass, self._command_topic, self._payload_on,
self._qos, self._retain)
if self._optimistic:
# Optimistically assume that switch has changed state.
self._state = True
self.update_ha_state()
def turn_off(self, **kwargs):
"""Turn the device off."""
mqtt.publish(self.hass, self._command_topic, self._payload_off,
self._qos, self._retain)
if self._optimistic:
# Optimistically assume that switch has changed state.
self._state = False
self.update_ha_state()