[virt-tools-list] [virt-manager PATCH] host: catch KeyError in interface_selected

[Chen Hanxiao]

> -----Original Message-----
> From: Cole Robinson [mailto:crobinso at redhat.com]
> Sent: Tuesday, March 11, 2014 11:54 PM
> To: Chen Hanxiao; Chen Hanxiao; virt-tools-list at redhat.com
> Subject: Re: [virt-tools-list] [virt-manager PATCH] host: catch KeyError
in
> interface_selected
> 
> On 03/11/2014 11:34 AM, Chen Hanxiao wrote:
> >
> > On 03/11/2014 08:26 PM, Cole Robinson wrote:
> >> On 03/11/2014 03:12 AM, Chen Hanxiao wrote:
> >>> We should catch KeyError in interface_selected,
> >>> for that error could happen when
> >>> singal on_interface_list_changed comes.
> >>>
> >>> How to reproduce:
> >>> 1. create 3 bridge by Edit->Connection Details->Network Interface
> >>> 2. delete them
> >>> 3. We would get a KeyError
> >>>
> >>> Signed-off-by: Chen Hanxiao <chenhanxiao at cn.fujitsu.com>
> >>> ---
> >>>   virtManager/host.py | 9 +++++++++
> >>>   1 file changed, 9 insertions(+)
> >>>
> >>> diff --git a/virtManager/host.py b/virtManager/host.py
> >>> index c8d7ee0..97a4f74 100644
> >>> --- a/virtManager/host.py
> >>> +++ b/virtManager/host.py
> >>> @@ -1098,6 +1098,15 @@ class vmmHost(vmmGObjectUI):
> >>>           name = model[treeiter][0]
> >>>             try:
> >>> +            self.conn.get_interface(name)
> >>> +        except KeyError:
> >>> +            self.widget("interface-apply").set_sensitive(False)
> >>> +            return
> >>> +        except Exception, e:
> >>> +            logging.exception(e)
> >>> +            self.set_interface_error_page(_("Error selecting
interface:
> >>> %s") %
> >>> +                    e)
> >>> +        try:
> >>>               self.populate_interface_state(name)
> >>>           except Exception, e:
> >>>               logging.exception(e)
> >>>
> >> If an interface is removed, vmmConnection should emit
interface-removed,
> which
> >> calls host.py:repopulate_interfaces and should remove the missing
interface
> >> from the list before the user has a chance to select anything. If
that's not
> >> working we should figure out why that is.
> >>
> >> - Cole
> > When we delete interface by UI, interface list will be changed,
> > signal "on_interface_list_changed" will be raised and it will also
> > invoke interface_selected.
> > I think that caused this issue.
> 
> Does this reproduce with the test driver? I couldn't reproduce.
> Does this issue affect storage pools or virtual networks? If so, can we
find a
> general solution (since they all use the same pattern). If not, what is
> different about the interface bits here?
> 
I spot this issue by manual test. And I could reproduce it on Fedora20 and
RHEL7.

Pls open debug logs of virt-manager, we could see the error message there.
1. add 2 bridges by UI
2. add 1 vlan by UI
3. delete the newly added vlan

Traceback (most recent call last):
  File "/root/virt-manager/virtManager/host.py", line 1101, in
interface_selected
    self.populate_interface_state(name)
  File "/root/virt-manager/virtManager/host.py", line 1110, in
populate_interface_state
    interface = self.conn.get_interface(name)
  File "/root/virt-manager/virtManager/connection.py", line 691, in
get_interface
    return self.interfaces[name]
KeyError: 'enp6s0f0.0'

Thanks
- Chen

> Generally any change like this in host.py should take a look at the other
> object handling as well, since storage/network/interface handling is near
> identical.
> 
> - Cole