Add binary_sensor for Tank Full status of dehumidifiers

Incude a fault_code attribute for debugging/further info

README.md

@@ -31,6 +31,9 @@ Current temperature is displayed, and current humidity is available as a propert
 **Lock** (heaters and dehumidifiers)
 * **Child lock** (on/off)
 
+**Binary Sensor** (dehumidifiers)
+* **Tank full** (on/off)
+
 There was previously a sensor option, however this is easily achieved using a [template sensor](https://www.home-assistant.io/integrations/template/) and therefore is no longer supported.
 
 ---
@@ -101,6 +104,9 @@ goldair_climate:
 
     *Default value: false* 
 
+#### tank_full
+    *(boolean) (Optional)* Whether to surface this appliances's tank full sensor as a binary_sensor device (only supported for dehumidifiers).
+
 Heater gotchas
 --------------
 Goldair heaters have individual target temperatures for their Comfort and Eco modes, whereas Home Assistant only supports

custom_components/goldair_climate/__init__.py

@@ -33,6 +33,7 @@ CONF_TYPE_FAN = 'fan'
 CONF_CLIMATE = 'climate'
 CONF_DISPLAY_LIGHT = 'display_light'
 CONF_CHILD_LOCK = 'child_lock'
+CONF_TANK_FULL = 'tank_full'
 
 PLATFORM_SCHEMA = vol.Schema({
     vol.Required(CONF_NAME): cv.string,
@@ -43,6 +44,7 @@ PLATFORM_SCHEMA = vol.Schema({
     vol.Optional(CONF_CLIMATE, default=True): cv.boolean,
     vol.Optional(CONF_DISPLAY_LIGHT, default=False): cv.boolean,
     vol.Optional(CONF_CHILD_LOCK, default=False): cv.boolean,
+    vol.Optional(CONF_TANK_FULL, default=False): cv.boolean,
 })
 
 CONFIG_SCHEMA = vol.Schema({
@@ -70,6 +72,8 @@ def setup(hass, config):
             load_platform(hass, 'light', DOMAIN, discovery_info, config)
         if device_config.get(CONF_CHILD_LOCK) == True:
             load_platform(hass, 'lock', DOMAIN, discovery_info, config)
+        if device_config.get(CONF_TANK_FULL) == True:
+            load_platform(hass, 'binary_sensor', DOMAIN, discovery_info, config)
 
     return True
 

custom_components/goldair_climate/binary_sensor.py

@@ -0,0 +1,18 @@
+"""
+Setup for different kinds of Goldair climate devices
+"""
+from homeassistant.const import CONF_HOST
+from custom_components.goldair_climate import (
+    DOMAIN, CONF_TYPE, CONF_TYPE_HEATER, CONF_TYPE_DEHUMIDIFIER, CONF_TYPE_FAN
+)
+from custom_components.goldair_climate.dehumidifier.binary_sensor import GoldairDehumidifierTankFullBinarySensor
+
+def setup_platform(hass, config, add_devices, discovery_info=None):
+    """Set up the Goldair climate device according to its type."""
+    device = hass.data[DOMAIN][discovery_info[CONF_HOST]]
+    if discovery_info[CONF_TYPE] == CONF_TYPE_DEHUMIDIFIER:
+        add_devices([GoldairDehumidifierTankFullBinarySensor(device)])
+    if discovery_info[CONF_TYPE] == CONF_TYPE_HEATER:
+        raise ValueError('Goldair heaters do not support tank full sensors.')
+    if discovery_info[CONF_TYPE] == CONF_TYPE_FAN:
+        raise ValueError('Goldair fans do not support tank full sensors.')

custom_components/goldair_climate/dehumidifier/binary_sensor.py

@@ -0,0 +1,63 @@
+"""
+Platform to sense whether the dehumidifier tank is full.
+"""
+
+from homeassistant.components.binary_sensor import (BinarySensorDevice, DEVICE_CLASS_PROBLEM)
+from custom_components.goldair_climate import GoldairTuyaDevice
+from custom_components.goldair_climate.dehumidifier.climate import (
+    ATTR_FAULT, FAULT_CODE_TO_DPS_CODE, PROPERTY_TO_DPS_ID
+)
+
+ATTR_FAULT_CODE = 'fault_code'
+FAULT_TANK = 8
+FAULT_NONE = 0
+
+class GoldairDehumidifierTankFullBinarySensor(BinarySensorDevice):
+    """Representation of a Goldair WiFi-connected dehumidifier Tank sensor."""
+
+    def __init__(self, device):
+        """Initialize the binary sensor.
+        Args:
+            device (GoldairTuyaDevice): The device API instance."""
+        self._device = device
+        self._fault = None
+
+    @property
+    def should_poll(self):
+        """Return the polling state"""
+        return True
+
+    @property
+    def name(self):
+        """Return the name of the binary sensor."""
+        return self._device.name
+
+    @property
+    def is_on(self):
+        """Return true if the tank is full."""
+        if (self._fault is None):
+            return None
+        else:
+            return self._fault == FAULT_TANK
+
+    @property
+    def device_class(self):
+        """Return the class of device."""
+        return DEVICE_CLASS_PROBLEM
+
+    @property
+    def device_state_attributes(self):
+        """Return the state attributes"""
+        attrs = {ATTR_FAULT_CODE: self._fault}
+        # attrs.update(super().device_state_attributes)
+        return attrs
+
+    @property
+    def available(self):
+        """Return true if the device is available and value has not expired"""
+        return self._fault is not None
+
+    def update(self):
+        self._device.refresh()
+        self._fault = self._device.get_property(PROPERTY_TO_DPS_ID[ATTR_FAULT])
+