Automate rsync w/ authentication

[Chris Rebert]

On Fri, Jul 10, 2009 at 9:13 AM, Bryan<bryanvick at gmail.com> wrote:
> I am trying to automate rsync to backup server A from server B.  I
> have set up a private/public key between the two servers so I don't
> have to enter a password when using rsync.  Running rsync manually
> with the following command works fine:
> rsync -av --dry-run -e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"
> root at 10.0.45.67:/home/bry/jquery.lookup /home/bry/tmp
>
> But when I try to do it with python, the subprocess simply returns the
> ssh -h output on stderr like I am passing some invalid syntax.  What
> is wrong in my translation of rsync's -e command from shell to
> pythyon?
>
> #! /usr/bin/python
> from subprocess import Popen, PIPE
> rsyncExec = '/usr/bin/ssh'
> source = 'root at 10.0.45.67:/home/bry/jquery.lookup'
> dest = '/home/bry/tmp'
> rshArg = '-e "/usr/bin/ssh -i /home/bry/keys/brybackup.key"'
> args = [rsyncExec, '-a', '-v', '--dry-run', rshArg, source, dest]

Like many problems involving the subprocess module, I think you've
tokenized the arguments incorrectly. Try:

rshArg = '"/usr/bin/ssh -i /home/bry/keys/brybackup.key"'
args = [rsyncExec, '-av', '--dry-run', '-e', rshArg, source, dest]

Note that the -e switch and its operand are separate arguments for the
purposes of POSIX shell tokenization.

Cheers,
Chris
-- 
http://blog.rebertia.com