Do not delete old notifications when user unsubscribes + allow notifications to…

Do not delete old notifications when user unsubscribes + allow notifications to be created without a subscription (to enable notifications for only one specific user)

django_notify/decorators.py

@@ -6,7 +6,12 @@ from django.contrib.auth.decorators import login_required
 import django_notify
 
 def disable_notify(func):
-    """Disable notifications within a """
+    """Disable notifications. Example:
+    
+    @disable_notify
+    def your_function():
+        notify("no one will be notified", ...)
+    """
     def wrap(request, *args, **kwargs):
         django_notify._disable_notifications = True
         response = func(request, *args, **kwargs)

django_notify/models.py

@@ -58,7 +58,7 @@ class Subscription(models.Model):
 
 class Notification(models.Model):
     
-    subscription = models.ForeignKey(Subscription)
+    subscription = models.ForeignKey(Subscription, null=True, blank=True, on_delete=models.SET_NULL)
     message = models.TextField()
     url = models.URLField(blank=True, null=True, verbose_name=_(u'link for notification'))
     is_viewed = models.BooleanField(default=False)