Catch exceptions in button handlers

i3pystatus/core/modules.py

@@ -94,6 +94,7 @@ class Module(SettingsBase):
         else:
             args = []
 
+        try:
             our_method = is_method_of(cb, self)
             if callable(cb) and not our_method:
                 self.__log_button_event(button, cb, args, "Python callback")
@@ -113,6 +114,8 @@ class Module(SettingsBase):
                     args = [arg.format(**self.data) for arg in args]
                     cb = cb.format(**self.data)
                 execute(cb + " " + " ".join(args), detach=True)
+        except Exception as e:
+            self.logger.critical("Exception while processing button callback: {!r}".format(e))
 
         # Notify status handler
         try: