Soma cover battery level attribute (#44459)

.coveragerc

@@ -828,8 +828,9 @@ omit =
     homeassistant/components/solaredge_local/sensor.py
     homeassistant/components/solarlog/*
     homeassistant/components/solax/sensor.py
-    homeassistant/components/soma/cover.py
     homeassistant/components/soma/__init__.py
+    homeassistant/components/soma/cover.py
+    homeassistant/components/soma/sensor.py
     homeassistant/components/somfy/*
     homeassistant/components/somfy_mylink/*
     homeassistant/components/sonos/*

homeassistant/components/soma/__init__.py

@@ -27,7 +27,7 @@ CONFIG_SCHEMA = vol.Schema(
     extra=vol.ALLOW_EXTRA,
 )
 
-SOMA_COMPONENTS = ["cover"]
+SOMA_COMPONENTS = ["cover", "sensor"]
 
 
 async def async_setup(hass, config):
@@ -74,6 +74,7 @@ class SomaEntity(Entity):
         self.device = device
         self.api = api
         self.current_position = 50
+        self.battery_state = 0
         self.is_available = True
 
     @property
@@ -120,4 +121,25 @@ class SomaEntity(Entity):
             self.is_available = False
             return
         self.current_position = 100 - response["position"]
+        try:
+            response = await self.hass.async_add_executor_job(
+                self.api.get_battery_level, self.device["mac"]
+            )
+        except RequestException:
+            _LOGGER.error("Connection to SOMA Connect failed")
+            self.is_available = False
+            return
+        if response["result"] != "success":
+            _LOGGER.error(
+                "Unable to reach device %s (%s)", self.device["name"], response["msg"]
+            )
+            self.is_available = False
+            return
+        # https://support.somasmarthome.com/hc/en-us/articles/360026064234-HTTP-API
+        # battery_level response is expected to be min = 360, max 410 for
+        # 0-100% levels above 410 are consider 100% and below 360, 0% as the
+        # device considers 360 the minimum to move the motor.
+        _battery = round(2 * (response["battery_level"] - 360))
+        battery = max(min(100, _battery), 0)
+        self.battery_state = battery
         self.is_available = True

homeassistant/components/soma/sensor.py

@@ -0,0 +1,40 @@
+"""Support for Soma sensors."""
+from homeassistant.const import DEVICE_CLASS_BATTERY, PERCENTAGE
+from homeassistant.helpers.entity import Entity
+
+from . import DEVICES, SomaEntity
+from .const import API, DOMAIN
+
+
+async def async_setup_entry(hass, config_entry, async_add_entities):
+    """Set up the Soma sensor platform."""
+
+    devices = hass.data[DOMAIN][DEVICES]
+
+    async_add_entities(
+        [SomaSensor(sensor, hass.data[DOMAIN][API]) for sensor in devices], True
+    )
+
+
+class SomaSensor(SomaEntity, Entity):
+    """Representation of a Soma cover device."""
+
+    @property
+    def device_class(self):
+        """Return the class of this device, from component DEVICE_CLASSES."""
+        return DEVICE_CLASS_BATTERY
+
+    @property
+    def name(self):
+        """Return the name of the device."""
+        return self.device["name"] + " battery level"
+
+    @property
+    def state(self):
+        """Return the state of the entity."""
+        return self.battery_state
+
+    @property
+    def unit_of_measurement(self):
+        """Return the unit of measurement this sensor expresses itself in."""
+        return PERCENTAGE