Add geniushub sensors for issues (#23976)

* Inital commit

* delint - use new string formatting

homeassistant/components/geniushub/sensor.py

@@ -14,6 +14,12 @@ _LOGGER = logging.getLogger(__name__)
 GH_HAS_BATTERY = [
     'Room Thermostat', 'Genius Valve', 'Room Sensor', 'Radiator Valve']
 
+GH_LEVEL_MAPPING = {
+    'error': 'Errors',
+    'warning': 'Warnings',
+    'information': 'Information'
+}
+
 
 async def async_setup_platform(hass, config, async_add_entities,
                                discovery_info=None):
@@ -23,7 +29,10 @@ async def async_setup_platform(hass, config, async_add_entities,
     sensors = [GeniusDevice(client, d)
                for d in client.hub.device_objs if d.type in GH_HAS_BATTERY]
 
-    async_add_entities(sensors)
+    issues = [GeniusIssue(client, i)
+              for i in list(GH_LEVEL_MAPPING)]
+
+    async_add_entities(sensors + issues, update_before_add=True)
 
 
 class GeniusDevice(Entity):
@@ -80,3 +89,47 @@ class GeniusDevice(Entity):
             last_comms).isoformat()
 
         return {**attrs}
+
+
+class GeniusIssue(Entity):
+    """Representation of a Genius Hub sensor."""
+
+    def __init__(self, client, level):
+        """Initialize the sensor."""
+        self._hub = client.hub
+        self._name = GH_LEVEL_MAPPING[level]
+        self._level = level
+        self._issues = []
+
+    async def async_added_to_hass(self):
+        """Set up a listener when this entity is added to HA."""
+        async_dispatcher_connect(self.hass, DOMAIN, self._refresh)
+
+    @callback
+    def _refresh(self):
+        self.async_schedule_update_ha_state(force_refresh=True)
+
+    @property
+    def name(self):
+        """Return the name of the sensor."""
+        return self._name
+
+    @property
+    def should_poll(self) -> bool:
+        """Return False as the geniushub devices should not be polled."""
+        return False
+
+    @property
+    def state(self):
+        """Return the number of issues."""
+        return len(self._issues)
+
+    @property
+    def device_state_attributes(self):
+        """Return the device state attributes."""
+        return {'{}_list'.format(self._level): self._issues}
+
+    async def async_update(self):
+        """Process the sensor's state data."""
+        self._issues = [i['description']
+                        for i in self._hub.issues if i['level'] == self._level]