| """ |
| Support for MQTT discovery. |
| |
| For more details about this component, please refer to the documentation at |
| https://home-assistant.io/components/mqtt/#discovery |
| """ |
| import asyncio |
| import json |
| import logging |
| import re |
|
|
| import homeassistant.components.mqtt as mqtt |
| from homeassistant.helpers.discovery import async_load_platform |
| from homeassistant.const import CONF_PLATFORM |
| from homeassistant.components.mqtt import CONF_STATE_TOPIC |
|
|
| _LOGGER = logging.getLogger(__name__) |
|
|
| TOPIC_MATCHER = re.compile( |
| r'(?P<prefix_topic>\w+)/(?P<component>\w+)/' |
| r'(?:(?P<node_id>[a-zA-Z0-9_-]+)/)?(?P<object_id>[a-zA-Z0-9_-]+)/config') |
|
|
| SUPPORTED_COMPONENTS = ['binary_sensor', 'light', 'sensor', 'switch'] |
|
|
| ALLOWED_PLATFORMS = { |
| 'binary_sensor': ['mqtt'], |
| 'light': ['mqtt', 'mqtt_json', 'mqtt_template'], |
| 'sensor': ['mqtt'], |
| 'switch': ['mqtt'], |
| } |
|
|
| ALREADY_DISCOVERED = 'mqtt_discovered_components' |
|
|
|
|
| @asyncio.coroutine |
| def async_start(hass, discovery_topic, hass_config): |
| """Initialize of MQTT Discovery.""" |
| |
| @asyncio.coroutine |
| def async_device_message_received(topic, payload, qos): |
| """Process the received message.""" |
| match = TOPIC_MATCHER.match(topic) |
|
|
| if not match: |
| return |
|
|
| prefix_topic, component, node_id, object_id = match.groups() |
|
|
| try: |
| payload = json.loads(payload) |
| except ValueError: |
| _LOGGER.warning("Unable to parse JSON %s: %s", object_id, payload) |
| return |
|
|
| if component not in SUPPORTED_COMPONENTS: |
| _LOGGER.warning("Component %s is not supported", component) |
| return |
|
|
| payload = dict(payload) |
| platform = payload.get(CONF_PLATFORM, 'mqtt') |
| if platform not in ALLOWED_PLATFORMS.get(component, []): |
| _LOGGER.warning("Platform %s (component %s) is not allowed", |
| platform, component) |
| return |
|
|
| payload[CONF_PLATFORM] = platform |
| if CONF_STATE_TOPIC not in payload: |
| payload[CONF_STATE_TOPIC] = '{}/{}/{}{}/state'.format( |
| discovery_topic, component, '%s/' % node_id if node_id else '', |
| object_id) |
|
|
| if ALREADY_DISCOVERED not in hass.data: |
| hass.data[ALREADY_DISCOVERED] = set() |
|
|
| |
| discovery_id = '_'.join((node_id, object_id)) if node_id else object_id |
|
|
| discovery_hash = (component, discovery_id) |
| if discovery_hash in hass.data[ALREADY_DISCOVERED]: |
| _LOGGER.info("Component has already been discovered: %s %s", |
| component, discovery_id) |
| return |
|
|
| hass.data[ALREADY_DISCOVERED].add(discovery_hash) |
|
|
| _LOGGER.info("Found new component: %s %s", component, discovery_id) |
|
|
| yield from async_load_platform( |
| hass, component, platform, payload, hass_config) |
|
|
| yield from mqtt.async_subscribe( |
| hass, discovery_topic + '/#', async_device_message_received, 0) |
|
|
| return True |
|
|
