Added Philips Hue lights backend to monitor status changes to the lights

docs/source/backends.rst

@@ -15,6 +15,7 @@ Backends
     platypush/backend/http.rst
     platypush/backend/inotify.rst
     platypush/backend/kafka.rst
+    platypush/backend/light.hue.rst
     platypush/backend/midi.rst
     platypush/backend/mqtt.rst
     platypush/backend/music.mpd.rst

docs/source/events.rst

@@ -13,6 +13,7 @@ Events
     platypush/events/http.rst
     platypush/events/joystick.rst
     platypush/events/kafka.rst
+    platypush/events/light.rst
     platypush/events/midi.rst
     platypush/events/music.rst
     platypush/events/music.snapcast.rst

platypush/backend/light/hue.py

@@ -0,0 +1,93 @@
+import json
+import time
+
+from threading import Thread
+
+from platypush.backend import Backend
+from platypush.context import get_plugin
+from platypush.message.event.light import LightStatusChangeEvent
+
+
+class LightHueBackend(Backend):
+    """
+    This backend will periodically check for the status of your configured
+    Philips Hue light devices and trigger events when the status of a device
+    (power, saturation, brightness or hue) changes.
+
+    Triggers:
+
+        * :class:`platypush.message.event.light.LightStatusChangeEvent` when the
+            status of a lightbulb changes
+
+    Requires:
+
+        * The :class:`platypush.plugins.light.hue.LightHuePlugin` plugin to be
+            active and configured.
+    """
+
+    _DEFAULT_POLL_SECONDS = 10
+
+    def __init__(self, poll_seconds=_DEFAULT_POLL_SECONDS, *args, **kwargs):
+        """
+        :param poll_seconds: How often the backend will poll the Hue plugin for
+            status updates. Default: 10 seconds
+        :type poll_seconds: float
+        """
+
+        super().__init__(*args, **kwargs)
+        self.poll_seconds = poll_seconds
+
+
+    def _get_lights(self):
+        return get_plugin('light.hue').get_lights().output
+
+    def _listener(self):
+        def _thread():
+            lights = self._get_lights()
+
+            while not self.should_stop():
+                try:
+                    lights_new = self._get_lights()
+
+                    for light_id, light in lights_new.items():
+                        event_args = {}
+                        state = light.get('state')
+                        prev_state = lights.get(light_id, {}).get('state', {})
+
+                        if 'on' in state and state.get('on') != prev_state.get('on'):
+                            event_args['on'] = state.get('on')
+                        if 'bri' in state and state.get('bri') != prev_state.get('bri'):
+                            event_args['bri'] = state.get('bri')
+                        if 'sat' in state and state.get('sat') != prev_state.get('sat'):
+                            event_args['sat'] = state.get('sat')
+                        if 'hue' in state and state.get('hue') != prev_state.get('hue'):
+                            event_args['hue'] = state.get('hue')
+                        if 'ct' in state and state.get('ct') != prev_state.get('ct'):
+                            event_args['ct'] = state.get('ct')
+
+                        if event_args:
+                            event_args['light_id'] = light_id
+                            event_args['light_name'] = light.get('name')
+                            self.bus.post(LightStatusChangeEvent(**event_args))
+
+                    lights = lights_new
+                except Exception as e:
+                    self.logger.exception(e)
+                finally:
+                    time.sleep(self.poll_seconds)
+
+        return _thread
+
+    def run(self):
+        super().run()
+
+        while not self.should_stop():
+            try:
+                poll_thread = Thread(target=self._listener())
+                poll_thread.start()
+                poll_thread.join()
+            except Exception as e:
+                self.logger.exception(e)
+                time.sleep(self.poll_seconds)
+
+# vim:sw=4:ts=4:et:

platypush/message/event/light.py

@@ -0,0 +1,55 @@
+from platypush.message.event import Event
+
+
+class LightStatusChangeEvent(Event):
+    """
+    Event triggered when the state of a lightbulb changes
+    """
+
+    def __init__(self, light_id=None, light_name=None, on=None, bri=None,
+                 sat=None, hue=None, ct=None, *args, **kwargs):
+        """
+        :param light_id: Light ID that triggered the event
+        :type light_id: int
+
+        :param light_name: Light name that triggered the event
+        :type light_name: str
+
+        :param on: Set if the power state of the bulb changed
+        :type on: bool
+
+        :param bri: Set if the brightness state of the bulb changed
+        :type bri: int
+
+        :param sat: Set if the saturation state of the bulb changed
+        :type sat: int
+
+        :param hue: Set if the hue state of the bulb changed
+        :type hue: int
+
+        :param ct: Set if the color temperature state of the bulb changed
+        :type ct: int
+        """
+
+        attrs = {}
+
+        if light_id is not None:
+            attrs['light_id'] = light_id
+        if light_name is not None:
+            attrs['light_name'] = light_name
+        if on is not None:
+            attrs['on'] = on
+        if bri is not None:
+            attrs['bri'] = bri
+        if sat is not None:
+            attrs['sat'] = sat
+        if hue is not None:
+            attrs['hue'] = hue
+        if ct is not None:
+            attrs['ct'] = ct
+
+        super().__init__(*args, **attrs, **kwargs)
+
+
+# vim:sw=4:ts=4:et:
+