[ovirt-devel] python path conflicts issues while running python scripts from vdsm verbs

[Dan Kenigsberg]

Regardless of the solution you plan to take, let it serve as a reminder
about moving gluster bits out of /usr/share/vdsm/ and into
site-packages. I am willing to pay the price of an ugly
exception-handling in xmlrpc, if this is the cost.

On Wed, Nov 30, 2016 at 11:27:06AM +0530, Aravinda wrote:
> If vdsm setting PYTHONPATH as below
> 
>     export PYTHONPATH=/usr/share/vdsm:$PYTHONPATH
> 
> change it as
> 
>     export PYTHONPATH=$PYTHONPATH:/usr/share/vdsm
> 
> With this change, /usr/share/vdsm will not get first preference compared to
> /usr/lib*/python2.7/site-packages
> 
> regards
> Aravinda
> 
> On 11/30/2016 10:25 AM, Ramesh Nachimuthu wrote:
> > 
> > 
> > 
> > ----- Original Message -----
> > > From: "Nir Soffer" <nsoffer at redhat.com>
> > > To: "Ramesh Nachimuthu" <rnachimu at redhat.com>
> > > Cc: "devel" <devel at ovirt.org>, "Dan Kenigsberg" <danken at redhat.com>, "Piotr Kliczewski" <pkliczew at redhat.com>, "Yaniv
> > > Bronheim" <ybronhei at redhat.com>, "Aravinda Vishwanathapura Krishna Murthy" <avishwan at redhat.com>, "Sahina Bose"
> > > <sabose at redhat.com>
> > > Sent: Tuesday, November 29, 2016 7:20:57 PM
> > > Subject: Re: python path conflicts issues while running python scripts from vdsm verbs
> > > 
> > > On Tue, Nov 29, 2016 at 3:26 PM, Ramesh Nachimuthu <rnachimu at redhat.com>
> > > wrote:
> > > > Hi,
> > > > 
> > > >   I am trying to run a python script '/sbin/gluster-eventsapi' in vdsm verb
> > > >   which internally imports some python modules from
> > > >   /usr/lib/python2.7/site-packages/gluster/cliutils/. But it fails with the
> > > >   import error. Following error is seen in the supervdsm log.
> > > > 
> > > > 
> > > > MainProcess|Thread-1::DEBUG::2016-11-28
> > > > 16:54:35,130::commands::93::root::(execCmd) FAILED: <err> = 'Traceback
> > > > (most recent call last):\n  File "/sbin/gluster-eventsapi", line 25, in
> > > > <module>\n    from gluster.cliutils.cliutils import (Cmd, execute,
> > > > node_output_ok, node_output_notok,\nImportError: No module named
> > > > cliutils.cliutils\n'; <rc> = 1
> > > > 
> > > > 
> > > > I think the import statement "from gluster.cliutils.cliutils import (Cmd,
> > > > execute, node_output_ok, node_output_notok)" in the python script resolves
> > > > to '/usr/share/vdsm/gluster' instead of
> > > > /usr/lib/python2.7/site-packages/gluster/cliutils.
> > > > 
> > > > I see the following in python sys.path while executing a python script from
> > > > vdsm.
> > > > 
> > > > ['/usr/libexec/glusterfs', '/usr/share/vdsm', '/usr/lib64/python27.zip',
> > > > '/usr/lib64/python2.7', '/usr/lib64/python2.7/plat-linux2',
> > > > '/usr/lib64/python2.7/lib-tk', '/usr/lib64/python2.7/lib-old',
> > > > '/usr/lib64/python2.7/lib-dynload', '/usr/lib64/python2.7/site-packages',
> > > > '/usr/lib64/python2.7/site-packages/gtk-2.0',
> > > > '/usr/lib/python2.7/site-packages']
> > > > 
> > > > Looks like '/usr/share/vdsm' take precedence over
> > > > '/usr/lib64/python2.7/site-packages'.
> > > > 
> > > > Can someone suggests a way to fix this issue?
> > > > 
> > > > Note: '/sbin/gluster-eventsapi' works perfectly while running directly from
> > > > CLI.
> > > > 
> > > > Related vdsm patch:
> > > > https://gerrit.ovirt.org/#/c/67168/2/vdsm/gluster/events.py
> > > If an import fails because /usr/share/vdsm/foo hides a package in
> > > /usr/lib/python2.7/site-packages/vdsm it means that you have a wrong
> > > import, you need to import anything like this:
> > > 
> > >      from vdsm.foo import bar
> > > 
> > > So names in /usr/share/vdsm/* cannot hide names in vdsm package.
> > > 
> > Here its a different case. Some external python script (which I am trying to run from vdsm verb) is trying to import some gluster package from /usr/lib/python2.7/site-packages/gluster. But it is conflicting with gluster modules under /usr/share/vdsm/gluster
> > 
> > Python Script which I am trying to run: https://github.com/gluster/glusterfs/blob/master/events/src/peer_eventsapi.py
> > 
> > Regards,
> > Ramesh