[ovirt-devel] vdsm libs dependencies

[Edward Haas]

> On 9 Jun 2017, at 19:44, Dan Kenigsberg <danken at redhat.com> wrote:
> 
>> On Fri, Jun 9, 2017 at 2:49 PM, Pavel Gashev <Pax at acronis.com> wrote:
>> Hello,
>> 
>> 
>> 
>> I have a question about dependencies of vdsm libraries. Could somebody
>> suggest how I can use vdsm.network.ipwrapper from vdsm.storage?
>> 
>> 
>> 
>> Specifically, I need a way to determine that an IP address of NFS path is
>> local. The right way to determine that is as simple as the following:
>> 
>> 
>> 
>> # /sbin/ip route get X.X.X.X | grep -q ^local && echo IP is local
>> 
>> 
>> 
>> This is why I need to use vdsm.network.ipwrapper. See details at
>> https://gerrit.ovirt.org/#/c/68822/
> 
> I think that we should create a new
> vdsm.network.api.is_local_address() for this. Do you have a better
> idea, Edy?
> 
> P.S I just notice that we have a similar problem in already merged to iscsi.py:
> 
> from vdsm.network.netinfo.routes import getRouteDeviceTo
> 
> should be similarly avoided.

Anyone outside the network subtree accessing anything except the api module is in risk, as internals may be changed or removed. It is equivalent to accessing a private attribute in python. 

In general I am not in favor of contacting the network package for things that are not really its main business logic. Asking it if an IP is under one of the networks it manages seems fine, but asking this in general for the host is something else.
This could fit a helper in common.network, but we'll need execCmd moved to common first.

Thanks,
Edy.