Catch errors when connection to dbus

src/virtManager/connect.py

@@ -84,14 +84,15 @@ class vmmConnect(gobject.GObject):
 
         self.window.get_widget("conn-list").get_selection().connect("changed", self.conn_selected)
 
-        self.bus = dbus.SystemBus()
+        self.bus = None
+        self.server = None
+        self.can_browse = False
         try:
+            self.bus = dbus.SystemBus()
             self.server = dbus.Interface(self.bus.get_object("org.freedesktop.Avahi", "/"), "org.freedesktop.Avahi.Server")
             self.can_browse = True
         except Exception, e:
             logging.debug("Couldn't contact avahi: %s" % str(e))
-            self.server = None
-            self.can_browse = False
 
         self.reset_state()
 

src/virtManager/connection.py

@@ -773,9 +773,9 @@ class vmmConnection(gobject.GObject):
             logging.debug("Skipping policykit check as root")
             return 0
         logging.debug("Doing policykit for %s" % action)
-        bus = dbus.SessionBus()
 
         try:
+            bus = dbus.SessionBus()
             # First try to use org.freedesktop.PolicyKit.AuthenticationAgent
             # which is introduced with PolicyKit-0.7
             obj = bus.get_object("org.freedesktop.PolicyKit.AuthenticationAgent", "/")