Add unique_id to MQTT fan (#16949)

homeassistant/components/fan/mqtt.py

@@ -5,6 +5,7 @@ For more details about this platform, please refer to the documentation
 https://home-assistant.io/components/fan.mqtt/
 """
 import logging
+from typing import Optional
 
 import voluptuous as vol
 
@@ -41,6 +42,7 @@ CONF_PAYLOAD_LOW_SPEED = 'payload_low_speed'
 CONF_PAYLOAD_MEDIUM_SPEED = 'payload_medium_speed'
 CONF_PAYLOAD_HIGH_SPEED = 'payload_high_speed'
 CONF_SPEED_LIST = 'speeds'
+CONF_UNIQUE_ID = 'unique_id'
 
 DEFAULT_NAME = 'MQTT Fan'
 DEFAULT_PAYLOAD_ON = 'ON'
@@ -74,6 +76,7 @@ PLATFORM_SCHEMA = mqtt.MQTT_RW_PLATFORM_SCHEMA.extend({
                  default=[SPEED_OFF, SPEED_LOW,
                           SPEED_MEDIUM, SPEED_HIGH]): cv.ensure_list,
     vol.Optional(CONF_OPTIMISTIC, default=DEFAULT_OPTIMISTIC): cv.boolean,
+    vol.Optional(CONF_UNIQUE_ID): cv.string,
 }).extend(mqtt.MQTT_AVAILABILITY_SCHEMA.schema)
 
 
@@ -120,6 +123,7 @@ async def async_setup_platform(hass: HomeAssistantType, config: ConfigType,
         config.get(CONF_AVAILABILITY_TOPIC),
         config.get(CONF_PAYLOAD_AVAILABLE),
         config.get(CONF_PAYLOAD_NOT_AVAILABLE),
+        config.get(CONF_UNIQUE_ID),
         discovery_hash,
     )])
 
@@ -129,7 +133,8 @@ class MqttFan(MqttAvailability, MqttDiscoveryUpdate, FanEntity):
 
     def __init__(self, name, topic, templates, qos, retain, payload,
                  speed_list, optimistic, availability_topic, payload_available,
-                 payload_not_available, discovery_hash):
+                 payload_not_available, unique_id: Optional[str],
+                 discovery_hash):
         """Initialize the MQTT fan."""
         MqttAvailability.__init__(self, availability_topic, qos,
                                   payload_available, payload_not_available)
@@ -154,6 +159,7 @@ class MqttFan(MqttAvailability, MqttDiscoveryUpdate, FanEntity):
                                      is not None and SUPPORT_OSCILLATE)
         self._supported_features |= (topic[CONF_SPEED_STATE_TOPIC]
                                      is not None and SUPPORT_SET_SPEED)
+        self._unique_id = unique_id
         self._discovery_hash = discovery_hash
 
     async def async_added_to_hass(self):
@@ -323,3 +329,8 @@ class MqttFan(MqttAvailability, MqttDiscoveryUpdate, FanEntity):
         if self._optimistic_oscillation:
             self._oscillation = oscillating
             self.async_schedule_update_ha_state()
+
+    @property
+    def unique_id(self):
+        """Return a unique ID."""
+        return self._unique_id

tests/components/fan/test_mqtt.py

@@ -1,14 +1,14 @@
 """Test MQTT fans."""
 import unittest
 
-from homeassistant.setup import setup_component
+from homeassistant.setup import setup_component, async_setup_component
 from homeassistant.components import fan
 from homeassistant.components.mqtt.discovery import async_start
 from homeassistant.const import ATTR_ASSUMED_STATE, STATE_UNAVAILABLE
 
 from tests.common import (
     mock_mqtt_component, async_fire_mqtt_message, fire_mqtt_message,
-    get_test_home_assistant)
+    get_test_home_assistant, async_mock_mqtt_component)
 
 
 class TestMqttFan(unittest.TestCase):
@@ -125,3 +125,28 @@ async def test_discovery_removal_fan(hass, mqtt_mock, caplog):
     await hass.async_block_till_done()
     state = hass.states.get('fan.beer')
     assert state is None
+
+
+async def test_unique_id(hass):
+    """Test unique_id option only creates one fan per id."""
+    await async_mock_mqtt_component(hass)
+    assert await async_setup_component(hass, fan.DOMAIN, {
+        fan.DOMAIN: [{
+            'platform': 'mqtt',
+            'name': 'Test 1',
+            'state_topic': 'test-topic',
+            'command_topic': 'test-topic',
+            'unique_id': 'TOTALLY_UNIQUE'
+        }, {
+            'platform': 'mqtt',
+            'name': 'Test 2',
+            'state_topic': 'test-topic',
+            'command_topic': 'test-topic',
+            'unique_id': 'TOTALLY_UNIQUE'
+        }]
+    })
+
+    async_fire_mqtt_message(hass, 'test-topic', 'payload')
+    await hass.async_block_till_done()
+
+    assert len(hass.states.async_entity_ids(fan.DOMAIN)) == 1