From ee967c1e72d8d1093e38255912a75dfe61eb3f7c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marek=20Marczykowski-G=C3=B3recki?=
 <marmarek@invisiblethingslab.com>
Date: Mon, 10 Apr 2017 00:50:18 +0200
Subject: [PATCH] events: add function to remove event handlers

Event handlers for remote mgmt API will be registered dynamically, so
allow to unregister them.

QubesOS/qubes-issues#2622
---
 qubes/events.py | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/qubes/events.py b/qubes/events.py
index 03081b0b..4b15e480 100644
--- a/qubes/events.py
+++ b/qubes/events.py
@@ -115,6 +115,17 @@ class Emitter(object, metaclass=EmitterMeta):
         # pylint: disable=no-member
         cls.__handlers__[event].add(func)
 
+    @classmethod
+    def remove_handler(cls, event, func):
+        '''Remove event handler from subject's class.
+
+        :param str event: event identificator
+        :param collections.Callable handler: handler callable
+        '''
+
+        # pylint: disable=no-member
+        cls.__handlers__[event].remove(func)
+
 
     def _fire_event_in_order(self, order, event, kwargs):
         '''Fire event for classes in given order.