cc-4105: fixed first big event contracting bug

python_apps/media-monitor2/media/monitor/eventcontractor.py

@@ -2,6 +2,10 @@ from media.monitor.log import Loggable
 from media.monitor.events import DeleteFile
 
 class EventContractor(Loggable):
+    """
+    This class is responsible for "contracting" events together to ease the
+    load on airtime. It does this by morphing old events into newer ones
+    """
     def __init__(self):
         self.store = {}
 
@@ -12,18 +16,28 @@ class EventContractor(Loggable):
         return self.store[ evt.path ]
 
     def register(self, evt):
+        """
+        Returns true if event was actually registered. This means that
+        no old events were touched. On the other hand returns false if
+        some other event in the storage was morphed into this newer one.
+        Which should mean that the old event should be discarded.
+        """
         if self.event_registered(evt):
             old_e = self.get_old_event(evt)
+            # TODO : Perhaps there are other events that we can "contract"
+            # together
             # If two events are of the same type we can safely discard the old
             # one
             if evt.__class__ == old_e.__class__:
                 old_e.morph_into(evt)
+                return False
             # delete overrides any other event
             elif isinstance(evt, DeleteFile):
                 old_e.morph_into(evt)
-        else:
-            evt.add_safe_pack_hook( lambda : self.__unregister(evt) )
-            self.store[ evt.path ] = evt
+                return False
+        evt.add_safe_pack_hook( lambda : self.__unregister(evt) )
+        self.store[ evt.path ] = evt
+        return True # We actually added something, hence we return true.
 
     # events are unregistered automatically no need to screw around with them
     def __unregister(self, evt):