Subscription callbacks

SpiderMQTT.py

@@ -243,6 +243,7 @@ class Subscription:
     self.topic = Topic(topic)
     self.state = self.PENDING
     self.callbacks = set()
+    self.subscriptionCallbacks = set()
 
     self.__sub()
 
@@ -253,6 +254,11 @@ class Subscription:
   def onSubscribe(self, mid):
     if self.sub_mid == mid:
       self.state = self.ACTIVE
+      for callback in self.subscriptionCallbacks:
+        try:
+          callback()
+        except Exception as ex:
+          pass  # TODO: logging!
 
   def onMessage(self, msg):
     if self.topic.compare(msg.topic):
@@ -275,6 +281,13 @@ class Subscription:
     if callback in self.callbacks:
       self.callbacks.remove(callback)
 
+  def addSubscriptionCallback(self, callback):
+    self.subscriptionCallbacks.add(callback)
+
+  def removeSubscriptionCallback(self, callback):
+    if callback in self.subscriptionCallbacks:
+      self.subscriptionCallbacks.remove(callback)
+
 
 class SpiderMQTT: