Introducing support to Melnor RainCloud sprinkler systems (#9287)

*  Introducing support to Melnor RainCloud sprinkler systems

* Make monitored_conditions optional for sub-components

*  Part 1/2 - Modified attributes, added DATA_ constant and using battery helper

* Part 2/2 - Refactored self-update hub

* Fixed change requested:
- Dispatcher signal connection
- Don't send raincloud object via dispatcher_send()
- Honoring the dynamic scan_interval value on track_time_interval()

* Inherents async_added_to_hass() on all device classes

* Makes lint happy

* * Refactored RainCloud code to incorporate suggestions.
  Many thanks to @pvizelli and @martinhjelmare!!

* Removed Entity from RainCloud sensor and fixed docstrings

* Update raincloud.py

* Update raincloud.py

* fix lint

homeassistant/components/binary_sensor/raincloud.py

@@ -0,0 +1,70 @@
+"""
+Support for Melnor RainCloud sprinkler water timer.
+
+For more details about this platform, please refer to the documentation at
+https://home-assistant.io/components/binary_sensor.raincloud/
+"""
+import logging
+
+import voluptuous as vol
+
+import homeassistant.helpers.config_validation as cv
+from homeassistant.components.raincloud import (
+    BINARY_SENSORS, DATA_RAINCLOUD, ICON_MAP, RainCloudEntity)
+from homeassistant.components.binary_sensor import (
+    BinarySensorDevice, PLATFORM_SCHEMA)
+from homeassistant.const import CONF_MONITORED_CONDITIONS
+
+DEPENDENCIES = ['raincloud']
+
+_LOGGER = logging.getLogger(__name__)
+
+PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend({
+    vol.Optional(CONF_MONITORED_CONDITIONS, default=list(BINARY_SENSORS)):
+        vol.All(cv.ensure_list, [vol.In(BINARY_SENSORS)]),
+})
+
+
+def setup_platform(hass, config, add_devices, discovery_info=None):
+    """Set up a sensor for a raincloud device."""
+    raincloud = hass.data[DATA_RAINCLOUD].data
+
+    sensors = []
+    for sensor_type in config.get(CONF_MONITORED_CONDITIONS):
+        if sensor_type == 'status':
+            sensors.append(
+                RainCloudBinarySensor(raincloud.controller, sensor_type))
+            sensors.append(
+                RainCloudBinarySensor(raincloud.controller.faucet,
+                                      sensor_type))
+
+        else:
+            # create an sensor for each zone managed by faucet
+            for zone in raincloud.controller.faucet.zones:
+                sensors.append(RainCloudBinarySensor(zone, sensor_type))
+
+    add_devices(sensors, True)
+    return True
+
+
+class RainCloudBinarySensor(RainCloudEntity, BinarySensorDevice):
+    """A sensor implementation for raincloud device."""
+
+    @property
+    def is_on(self):
+        """Return true if the binary sensor is on."""
+        return self._state
+
+    def update(self):
+        """Get the latest data and updates the state."""
+        _LOGGER.debug("Updating RainCloud sensor: %s", self._name)
+        self._state = getattr(self.data, self._sensor_type)
+
+    @property
+    def icon(self):
+        """Return the icon of this device."""
+        if self._sensor_type == 'is_watering':
+            return 'mdi:water' if self.is_on else 'mdi:water-off'
+        elif self._sensor_type == 'status':
+            return 'mdi:pipe' if self.is_on else 'mdi:pipe-disconnected'
+        return ICON_MAP.get(self._sensor_type)