Add new config variable to MQTT light (#9304)

* Add new config variable to MQTT light

* Address reviewer's issues: refactor template render part.

* Update mqtt.py

homeassistant/components/light/mqtt.py

@@ -39,6 +39,7 @@ CONF_EFFECT_COMMAND_TOPIC = 'effect_command_topic'
 CONF_EFFECT_LIST = 'effect_list'
 CONF_EFFECT_STATE_TOPIC = 'effect_state_topic'
 CONF_EFFECT_VALUE_TEMPLATE = 'effect_value_template'
+CONF_RGB_COMMAND_TEMPLATE = 'rgb_command_template'
 CONF_RGB_COMMAND_TOPIC = 'rgb_command_topic'
 CONF_RGB_STATE_TOPIC = 'rgb_state_topic'
 CONF_RGB_VALUE_TEMPLATE = 'rgb_value_template'
@@ -75,6 +76,7 @@ PLATFORM_SCHEMA = mqtt.MQTT_RW_PLATFORM_SCHEMA.extend({
     vol.Optional(CONF_OPTIMISTIC, default=DEFAULT_OPTIMISTIC): cv.boolean,
     vol.Optional(CONF_PAYLOAD_OFF, default=DEFAULT_PAYLOAD_OFF): cv.string,
     vol.Optional(CONF_PAYLOAD_ON, default=DEFAULT_PAYLOAD_ON): cv.string,
+    vol.Optional(CONF_RGB_COMMAND_TEMPLATE): cv.template,
     vol.Optional(CONF_RGB_COMMAND_TOPIC): mqtt.valid_publish_topic,
     vol.Optional(CONF_RGB_STATE_TOPIC): mqtt.valid_subscribe_topic,
     vol.Optional(CONF_RGB_VALUE_TEMPLATE): cv.template,
@@ -125,6 +127,7 @@ def async_setup_platform(hass, config, async_add_devices, discovery_info=None):
             CONF_COLOR_TEMP: config.get(CONF_COLOR_TEMP_VALUE_TEMPLATE),
             CONF_EFFECT: config.get(CONF_EFFECT_VALUE_TEMPLATE),
             CONF_RGB: config.get(CONF_RGB_VALUE_TEMPLATE),
+            CONF_RGB_COMMAND_TEMPLATE: config.get(CONF_RGB_COMMAND_TEMPLATE),
             CONF_STATE: config.get(CONF_STATE_VALUE_TEMPLATE),
             CONF_WHITE_VALUE: config.get(CONF_WHITE_VALUE_TEMPLATE),
             CONF_XY: config.get(CONF_XY_VALUE_TEMPLATE),
@@ -397,10 +400,17 @@ class MqttLight(Light):
         if ATTR_RGB_COLOR in kwargs and \
            self._topic[CONF_RGB_COMMAND_TOPIC] is not None:
 
+            tpl = self._templates[CONF_RGB_COMMAND_TEMPLATE]
+            if tpl:
+                colors = {'red', 'green', 'blue'}
+                variables = {key: val for key, val in
+                             zip(colors, kwargs[ATTR_RGB_COLOR])}
+                rgb_color_str = tpl.async_render(variables)
+            else:
+                rgb_color_str = '{},{},{}'.format(*kwargs[ATTR_RGB_COLOR])
             mqtt.async_publish(
                 self.hass, self._topic[CONF_RGB_COMMAND_TOPIC],
-                '{},{},{}'.format(*kwargs[ATTR_RGB_COLOR]), self._qos,
-                self._retain)
+                rgb_color_str, self._qos, self._retain)
 
             if self._optimistic_rgb:
                 self._rgb = kwargs[ATTR_RGB_COLOR]

tests/components/light/test_mqtt.py

@@ -123,6 +123,20 @@ light:
   payload_on: "on"
   payload_off: "off"
 
+config for RGB Version with RGB command template:
+
+light:
+  platform: mqtt
+  name: "Office Light RGB"
+  state_topic: "office/rgb1/light/status"
+  command_topic: "office/rgb1/light/switch"
+  rgb_state_topic: "office/rgb1/rgb/status"
+  rgb_command_topic: "office/rgb1/rgb/set"
+  rgb_command_template: "{{ '#%02x%02x%02x' | format(red, green, blue)}}"
+  qos: 0
+  payload_on: "on"
+  payload_off: "off"
+
 """
 import unittest
 from unittest import mock
@@ -512,6 +526,38 @@ class TestLightMQTT(unittest.TestCase):
         self.assertEqual(80, state.attributes['white_value'])
         self.assertEqual((0.123, 0.123), state.attributes['xy_color'])
 
+    def test_sending_mqtt_rgb_command_with_template(self):
+        """Test the sending of RGB command with template."""
+        config = {light.DOMAIN: {
+            'platform': 'mqtt',
+            'name': 'test',
+            'command_topic': 'test_light_rgb/set',
+            'rgb_command_topic': 'test_light_rgb/rgb/set',
+            'rgb_command_template': '{{ "#%02x%02x%02x" | '
+                                    'format(red, green, blue)}}',
+            'payload_on': 'on',
+            'payload_off': 'off',
+            'qos': 0
+        }}
+
+        with assert_setup_component(1, light.DOMAIN):
+            assert setup_component(self.hass, light.DOMAIN, config)
+
+        state = self.hass.states.get('light.test')
+        self.assertEqual(STATE_OFF, state.state)
+
+        light.turn_on(self.hass, 'light.test', rgb_color=[255, 255, 255])
+        self.hass.block_till_done()
+
+        self.mock_publish().async_publish.assert_has_calls([
+            mock.call('test_light_rgb/set', 'on', 0, False),
+            mock.call('test_light_rgb/rgb/set', '#ffffff', 0, False),
+        ], any_order=True)
+
+        state = self.hass.states.get('light.test')
+        self.assertEqual(STATE_ON, state.state)
+        self.assertEqual((255, 255, 255), state.attributes['rgb_color'])
+
     def test_show_brightness_if_only_command_topic(self):
         """Test the brightness if only a command topic is present."""
         config = {light.DOMAIN: {