Add pre and post signals to haystack's update index command

apps/signaler/management/commands/update_index.py

@@ -0,0 +1,14 @@
+from haystack.management.commands import update_index
+
+from signaler.signals import post_update_index, pre_update_index
+
+
+class Command(update_index.Command):
+    """
+    Wrapper for the haystack's update_index command
+    """
+
+    def handle(self, *args, **kwargs):
+        pre_update_index.send(sender=self)
+        super(Command, self).handle(*args, **kwargs)
+        post_update_index.send(sender=self)

apps/signaler/signals.py

@@ -1,3 +1,5 @@
 from django.dispatch import Signal
 
 pre_collectstatic = Signal()
+pre_update_index = Signal()
+post_update_index = Signal()