Google calendar sync

eventplanner_gcal/signals.py

@@ -1,27 +1,67 @@
 from django.db.models.signals import post_save,pre_delete
 from django.dispatch import receiver
-from eventplanner.models import Event, EventParticipation
+from eventplanner.models import Event, EventParticipation, before_read
+
+from eventplanner_gcal.models import createGCalEvent, updateGCalEvent
+from eventplanner_gcal.models import deleteGCalEvent, syncParticipationFromGoogleToLocal
+
+
+class SignalLock:
+    def __init__(self):
+        self.locked=False
+
+    def __enter__(self):
+        if self.locked:
+            return False
+
+        self.locked=True
+        return True
+
+    def __exit__(self, type, value, traceback):
+        self.locked=False
+
+    def isLocked(self):
+        return self.locked
+
+signalLock = SignalLock()
 
-from eventplanner_gcal.models import createGCalEvent, updateGCalEvent, deleteGCalEvent
 
 @receiver( post_save,sender= Event)
-def event_post_save_handler(event, **kwargs):
-    created = kwargs['created']
-    if created:
-        createGCalEvent( event ).execute()
-    else:
-        updateGCalEvent( event ).execute()
+def event_post_save_handler( **kwargs):
+    if not signalLock.isLocked():
+        with signalLock:
+            event = kwargs['instance']
+            created = kwargs['created']
+            if created:
+                print("Creating Gcal event")
+                createGCalEvent( event ).execute()
+            else:
+                print( "Updating Gcal event")
+                updateGCalEvent( event ).execute()
+
 
 
 @receiver( pre_delete,sender= Event)
-def event_pre_delete_handler(event, **kwargs):
-    deleteGCalEvent( event ).execute()
-
+def event_pre_delete_handler( **kwargs):
+    if not signalLock.isLocked():
+        with signalLock:
+            event = kwargs['instance']
+            print ("Deleting GCAL event")
+            deleteGCalEvent( event ).execute()
 
 
 @receiver( post_save, sender=EventParticipation )
-def participation_post_save_handler(participation, **kwargs):
-    updateGCalEvent( participation.event ).execute()
-
+def participation_post_save_handler( **kwargs):
+    if not signalLock.isLocked():
+        with signalLock:
+            participation = kwargs['instance']
+            print("Participation post save -> update gcal")
+            updateGCalEvent( participation.event ).execute()
 
 
+@receiver( before_read, sender=EventParticipation )
+def participation_before_read_handler( **kwargs):
+    if not signalLock.isLocked():
+        with signalLock:
+            print("SyncParticipation from google")
+            syncParticipationFromGoogleToLocal()