Fix: prevent multiple objects of heat in case of config reload

heat/_Heat.py

@@ -1,5 +1,6 @@
 
 import datetime
+import logging
 import threading
 import time
 
@@ -7,26 +8,31 @@ import RPi.GPIO as GPIO
 
 class Heat(threading.Thread):
     def __init__(self, pin):
-        super(Heat, self).__init__()
+        threading.Thread.__init__(self)
         self.__pin = pin
         self.__state = False
+        self.__lock = threading.Lock()
 
         GPIO.setwarnings(False)
         GPIO.setmode(GPIO.BCM)
         GPIO.setup(pin, GPIO.OUT)
 
-        if GPIO.input(pin):
+        if not GPIO.input(pin):
             self.__state = True
         self.__run_condition = True
         self.__next_update = datetime.datetime.now()
 
     def on(self):
-        self.__state = True
-        GPIO.output(self.__pin, 0)
+        """Switch the heat on"""
+        with self.__lock:
+            self.__state = True
+            GPIO.output(self.__pin, 0)
 
     def off(self):
-        self.__state = False
-        GPIO.output(self.__pin, 1)
+        """Switch the heat off"""
+        with self.__lock:
+            self.__state = False
+            GPIO.output(self.__pin, 1)
 
     def run(self):
         self.__next_update = datetime.datetime.now()
@@ -43,8 +49,10 @@ class Heat(threading.Thread):
         self.off()
 
     def stop(self):
+        """Stop the controlling thead"""
         self.__run_condition = False
         self.join()
 
     def state(self):
+        """Return the state of the heat"""
         return self.__state