Added LIRC component for responding to IR remote commands

homeassistant/components/sensor/lirc.py

@@ -0,0 +1,109 @@
+"""
+LIRC interface to receive signals from a infrared remote control.
+
+This sensor will momentarily set state to various values as defined
+in the .lintrc file which can be interpreted in home-assistant to
+trigger various actions.
+
+Sending signals to other IR receivers can be accomplished with the
+shell_command component and the irsend command.
+"""
+
+import threading
+import time
+import logging
+
+from homeassistant.helpers.entity import Entity
+from homeassistant.const import EVENT_HOMEASSISTANT_STOP
+
+LIRC = None
+
+REQUIREMENTS = ['python-lirc==1.2.1']
+_LOGGER = logging.getLogger(__name__)
+ICON = 'mdi:remote'
+
+
+def setup_platform(hass, config, add_devices, discovery_info=None):
+    """Setup LIRC capability."""
+    # Perform safe import of third-party python-lirc module
+    try:
+        import lirc
+        global LIRC
+        LIRC = lirc
+    except ImportError:
+        _LOGGER.error("You are missing a required dependency: python-lirc.")
+        return False
+
+    LIRC.init('home-assistant', blocking=False)
+    sensor = LircSensor()
+    add_devices([sensor])
+
+    hass.bus.listen_once(EVENT_HOMEASSISTANT_STOP, sensor.stop)
+
+
+class LircSensor(Entity):
+    """Sensor entity for LIRC."""
+
+    def __init__(self, *args, **kwargs):
+        """Contruct a LircSensor entity."""
+        _LOGGER.info('Initializing LIRC sensor')
+        Entity.__init__(self, *args, **kwargs)
+        self.last_key_pressed = ''
+        self._lirc_interface = LircInterface(self)
+        self._lirc_interface.start()
+
+    @property
+    def name(self):
+        """Name of lirc sensor."""
+        return 'lirc'
+
+    @property
+    def state(self):
+        """State of LIRC sensor."""
+        return self.last_key_pressed
+
+    def update_state(self, new_state):
+        """Inform system of update when they occur."""
+        self.last_key_pressed = new_state
+        self.update_ha_state()
+
+    def stop(self, event):
+        """Kill the helper thread on stop."""
+        _LOGGER.info('Ending LIRC interface thread')
+        self._lirc_interface.stopped.set()
+
+
+class LircInterface(threading.Thread):
+    """
+    This interfaces with the lirc daemon to read IR commands.
+
+    When using lirc in blocking mode, sometimes repeated commands get produced
+    in the next read of a command so we use a thread here to just wait
+    around until a non-empty response is obtained from lirc.
+    """
+
+    def __init__(self, parent):
+        """Construct a LIRC interface object."""
+        threading.Thread.__init__(self)
+        self.stopped = threading.Event()
+        self._parent = parent
+
+    def run(self):
+        """Main loop of LIRC interface thread."""
+        while not self.stopped.isSet():
+            code = LIRC.nextcode()  # list; empty if no buttons pressed
+
+            # interpret result from python-lirc
+            if code:
+                code = code[0]
+            else:
+                code = ''
+
+            # update if changed.
+            if code != self._parent.state:
+                _LOGGER.info('Got new LIRC code %s', code)
+                self._parent.update_state(code)
+            else:
+                time.sleep(0.1)  # avoid high CPU in this thread
+
+        _LOGGER.info('LIRC interface thread stopped')

requirements_all.txt

@@ -262,6 +262,9 @@ pysnmp==4.2.5
 # homeassistant.components.sensor.forecast
 python-forecastio==1.3.4
 
+# homeassistant.components.sensor.lirc
+python-lirc==1.2.1
+
 # homeassistant.components.media_player.mpd
 python-mpd2==0.5.5