Improve MQTT JSON light to allow non-ambiguous states (#45522)

homeassistant/components/mqtt/light/schema_json.py

@@ -175,6 +175,43 @@ class MqttLightJson(MqttEntity, LightEntity, RestoreEntity):
         self._supported_features |= config[CONF_XY] and SUPPORT_COLOR
         self._supported_features |= config[CONF_HS] and SUPPORT_COLOR
 
+    def _parse_color(self, values):
+        try:
+            red = int(values["color"]["r"])
+            green = int(values["color"]["g"])
+            blue = int(values["color"]["b"])
+
+            return color_util.color_RGB_to_hs(red, green, blue)
+        except KeyError:
+            pass
+        except ValueError:
+            _LOGGER.warning("Invalid RGB color value received")
+            return self._hs
+
+        try:
+            x_color = float(values["color"]["x"])
+            y_color = float(values["color"]["y"])
+
+            return color_util.color_xy_to_hs(x_color, y_color)
+        except KeyError:
+            pass
+        except ValueError:
+            _LOGGER.warning("Invalid XY color value received")
+            return self._hs
+
+        try:
+            hue = float(values["color"]["h"])
+            saturation = float(values["color"]["s"])
+
+            return (hue, saturation)
+        except KeyError:
+            pass
+        except ValueError:
+            _LOGGER.warning("Invalid HS color value received")
+            return self._hs
+
+        return self._hs
+
     async def _subscribe_topics(self):
         """(Re)Subscribe to topics."""
         last_state = await self.async_get_last_state()
@@ -190,37 +227,11 @@ class MqttLightJson(MqttEntity, LightEntity, RestoreEntity):
             elif values["state"] == "OFF":
                 self._state = False
 
-            if self._supported_features and SUPPORT_COLOR:
-                try:
-                    red = int(values["color"]["r"])
-                    green = int(values["color"]["g"])
-                    blue = int(values["color"]["b"])
-
-                    self._hs = color_util.color_RGB_to_hs(red, green, blue)
-                except KeyError:
-                    pass
-                except ValueError:
-                    _LOGGER.warning("Invalid RGB color value received")
-
-                try:
-                    x_color = float(values["color"]["x"])
-                    y_color = float(values["color"]["y"])
-
-                    self._hs = color_util.color_xy_to_hs(x_color, y_color)
-                except KeyError:
-                    pass
-                except ValueError:
-                    _LOGGER.warning("Invalid XY color value received")
-
-                try:
-                    hue = float(values["color"]["h"])
-                    saturation = float(values["color"]["s"])
-
-                    self._hs = (hue, saturation)
-                except KeyError:
-                    pass
-                except ValueError:
-                    _LOGGER.warning("Invalid HS color value received")
+            if self._supported_features and SUPPORT_COLOR and "color" in values:
+                if values["color"] is None:
+                    self._hs = None
+                else:
+                    self._hs = self._parse_color(values)
 
             if self._supported_features and SUPPORT_BRIGHTNESS:
                 try:
@@ -236,7 +247,10 @@ class MqttLightJson(MqttEntity, LightEntity, RestoreEntity):
 
             if self._supported_features and SUPPORT_COLOR_TEMP:
                 try:
-                    self._color_temp = int(values["color_temp"])
+                    if values["color_temp"] is None:
+                        self._color_temp = None
+                    else:
+                        self._color_temp = int(values["color_temp"])
                 except KeyError:
                     pass
                 except ValueError:

tests/components/mqtt/test_light_json.py

@@ -295,11 +295,21 @@ async def test_controlling_state_via_topic(hass, mqtt_mock):
     light_state = hass.states.get("light.test")
     assert light_state.attributes.get("hs_color") == (180.0, 50.0)
 
+    async_fire_mqtt_message(hass, "test_light_rgb", '{"state":"ON", "color":null}')
+
+    light_state = hass.states.get("light.test")
+    assert "hs_color" not in light_state.attributes
+
     async_fire_mqtt_message(hass, "test_light_rgb", '{"state":"ON", "color_temp":155}')
 
     light_state = hass.states.get("light.test")
     assert light_state.attributes.get("color_temp") == 155
 
+    async_fire_mqtt_message(hass, "test_light_rgb", '{"state":"ON", "color_temp":null}')
+
+    light_state = hass.states.get("light.test")
+    assert "color_temp" not in light_state.attributes
+
     async_fire_mqtt_message(
         hass, "test_light_rgb", '{"state":"ON", "effect":"colorloop"}'
     )
@@ -1004,6 +1014,18 @@ async def test_invalid_values(hass, mqtt_mock):
     assert state.attributes.get("white_value") == 255
     assert state.attributes.get("color_temp") == 100
 
+    # Empty color value
+    async_fire_mqtt_message(
+        hass,
+        "test_light_rgb",
+        '{"state":"ON",' '"color":{}}',
+    )
+
+    # Color should not have changed
+    state = hass.states.get("light.test")
+    assert state.state == STATE_ON
+    assert state.attributes.get("rgb_color") == (255, 255, 255)
+
     # Bad HS color values
     async_fire_mqtt_message(
         hass,