Add sensor for Dweet.io

homeassistant/components/sensor/dweet.py

@@ -0,0 +1,119 @@
+"""
+homeassistant.components.sensor.dweet
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Displays values from Dweet.io..
+
+For more details about this platform, please refer to the documentation at
+https://home-assistant.io/components/sensor.dweet/
+"""
+from datetime import timedelta
+import logging
+
+import homeassistant.util as util
+from homeassistant.util import Throttle
+from homeassistant.helpers.entity import Entity
+from homeassistant.const import STATE_UNKNOWN
+
+_LOGGER = logging.getLogger(__name__)
+
+DEFAULT_NAME = 'Dweet.io Sensor'
+CONF_DEVICE = 'device'
+
+# Return cached results if last scan was less then this time ago
+MIN_TIME_BETWEEN_UPDATES = timedelta(seconds=60)
+
+
+# pylint: disable=unused-variable
+def setup_platform(hass, config, add_devices, discovery_info=None):
+    """ Setup the Dweet sensor. """
+
+    import dweepy
+
+    device = config.get('device')
+
+    if device is None:
+        _LOGGER.error('Not all required config keys present: %s',
+                      ', '.join(CONF_DEVICE))
+        return False
+
+    try:
+        dweepy.get_latest_dweet_for(device)
+    except dweepy.DweepyError:
+        _LOGGER.error("Device/thing '%s' could not be found", device)
+        return False
+
+    dweet = DweetData(device)
+
+    add_devices([DweetSensor(dweet,
+                             config.get('name', DEFAULT_NAME),
+                             config.get('variable'),
+                             config.get('unit_of_measurement'),
+                             config.get('correction_factor', None),
+                             config.get('decimal_places', None))])
+
+
+class DweetSensor(Entity):
+    """ Implements a Dweet sensor. """
+
+    def __init__(self, dweet, name, variable, unit_of_measurement, corr_factor,
+                 decimal_places):
+        self.dweet = dweet
+        self._name = name
+        self._variable = variable
+        self._state = STATE_UNKNOWN
+        self._unit_of_measurement = unit_of_measurement
+        self._corr_factor = corr_factor
+        self._decimal_places = decimal_places
+        self.update()
+
+    @property
+    def name(self):
+        """ The name of the sensor. """
+        return self._name
+
+    @property
+    def unit_of_measurement(self):
+        """ Unit the value is expressed in. """
+        return self._unit_of_measurement
+
+    @property
+    def state(self):
+        """ Returns the state. """
+        values = self.dweet.data
+
+        if values is not None:
+            value = util.extract_value_json(values[0]['content'],
+                                            self._variable)
+            if self._corr_factor is not None:
+                value = float(value) * float(self._corr_factor)
+            if self._decimal_places is not None:
+                value = round(value, self._decimal_places)
+            if self._decimal_places == 0:
+                value = int(value)
+            return value
+        else:
+            return STATE_UNKNOWN
+
+    def update(self):
+        """ Gets the latest data from REST API. """
+        self.dweet.update()
+
+
+# pylint: disable=too-few-public-methods
+class DweetData(object):
+    """ Class for handling the data retrieval. """
+
+    def __init__(self, device):
+        self._device = device
+        self.data = dict()
+
+    @Throttle(MIN_TIME_BETWEEN_UPDATES)
+    def update(self):
+        """ Gets the latest data from Dweet.io. """
+        import dweepy
+
+        try:
+            self.data = dweepy.get_latest_dweet_for(self._device)
+        except dweepy.DweepyError:
+            _LOGGER.error("Device '%s' could not be found", self._device)
+            self.data = None