cloud-init team mailing list archive

[Michael Felt <michael@xxxxxxxxxxxxx>]

On 19/12/2017 17:05, Robert Schweikert wrote:
> On 12/19/2017 10:14 AM, Scott Moser wrote:
> > The goal is to get off of net-tools (ifconfig and route) and over to 'ip'.
> > For freebsd and other things that do not have that, we'll have to keep
> > working.
> >
> > Ini python3, 'ipaddress'  is built in and we may be able to utilize it, but
> > I'm not interested in adding the python2 dependency.
> Does that imply that as long we support python2 we should shell out,
> i.e. use
>
> if util.which('netstat'):
>      return _route_info_from_netstat()
> elif util.which('ip'):
>      return _route_info_from_ip()

Considering your direction - I would go more towards:

if util.which('ip'):
    return _route_info_from_ip()
elif util.which('netstat'):
    return _route_info_from_netstat()

As, imho, you do not want to care if netstat is available UNLESS 'ip' is not available.

And, although it may be more work (initially) - are there library routines that can get the info you are looking for? I doubt it is uuid* family of calls, but there must be ways to call "what the *net*-utils call - rather than spawning subprocesses.
The hopeful upside is that that may be more portable than dealing with each potential distro change to "stdout" information.

> which is the direction I am working on now. I have the device
> information collection under control, working on the route information now.
>
> This direction would:
>    - avoid adding any new dependency for python2
>    - having to differentiate dependencies based on python version
>    - handle the freebsd case transparently
>
> Thanks,
> Robert