[lxc-users] is there a lxc-attach -v switch equivalent in lxc python bindings ?

[Benoit Barthelet]

it seems like there's a built-in kwarg, extra_env_vars, that does the -v
switch job of lxc-attach in fact, I wrapped it in a function here but it
could be written without :

def run_command(container, command, env={}):
    env['LANG'] = "C.UTF-8"
    env['TERM'] = "xterm"
    return container.attach_wait(
            lxc.attach_run_command, command,
            extra_env_vars=env, env_policy=lxc.LXC_ATTACH_CLEAR_ENV)

run_command(container, ["env", ])

returns :

PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
container=lxc
TERM=xterm
LANG=C.UTF-8

I managed to find it thanks to its use in
http://bazaar.launchpad.net/~ubuntu-lxc/lxc/steam-lxc/view/head:/steam-lxc

I couldn't find it documented, have I bad googling skills or is there a
place where I could have found it ?
If there isn't I'm ok to try document it, is there a dedicated place, wiki
for that or it's not worth the effort ?



On Tue, Mar 14, 2017 at 6:32 PM, Benoit Barthelet <
benoit.barthelet at gmail.com> wrote:

> thanks, that is exactly what I wanted !
>
> On Tue, Mar 14, 2017 at 1:37 PM, Stéphane Graber <stgraber at ubuntu.com>
> wrote:
>
>> On Tue, Mar 14, 2017 at 11:22:26AM +0100, Benoit Barthelet wrote:
>> > ultimately I'd like to do this in python:
>> >
>> > lxc-attach --clear-env -n lxcws -v TERM=xterm
>> >
>> > So far I managed to clear the env variables doing the following, but I
>> > didn't find a way to pass the TERM env variable.
>> >
>> > container.attach_wait(lxc.attach_run_command,
>> >                       ["apt-get", "dist-upgrade", "-y"],
>> >                       env_policy=lxc.LXC_ATTACH_CLEAR_ENV)
>>
>> Easiest I think is to use your own attach function instead of the
>> generic lxc.attach_run_command. In that function you can then set
>> os.environ as you want and call subprocess to run the command you want.
>>
>> In the lxc-ci code we have something like this:
>>
>>     def execute(self, cmd, cwd="/"):
>>         def run_command(args):
>>             cmd, cwd = args
>>
>>             os.environ['PATH'] = '/usr/sbin:/usr/bin:/sbin:/bin'
>>             os.environ['HOME'] = '/root'
>>             if "env" in config and "proxy" in config['env']:
>>                 os.environ["DEBIAN_FRONTEND"] = "noninteractive"
>>                 os.environ['http_proxy'] = config['env']['proxy']
>>                 os.environ['https_proxy'] = config['env']['proxy']
>>
>>             return subprocess.call(cmd, cwd=cwd)
>>
>>         if isinstance(cmd, str):
>>             pid = self.container.init_pid
>>             cmdpath = "/proc/%d/root/tmp/exec_script" % pid
>>             with open(cmdpath, "w+") as fd:
>>                 fd.write(cmd)
>>             os.chmod(cmdpath, 0o755)
>>             cmd = ["/tmp/exec_script"]
>>
>>         print(" ==> Executing: \"%s\" in %s" % (" ".join(cmd), cwd))
>>         return self.container.attach_wait(run_command,
>>                                           (cmd, cwd),
>>                                           env_policy=lxc.LXC_ATTACH_CLEA
>> R_ENV)
>>
>>
>>
>> --
>> Stéphane Graber
>> Ubuntu developer
>> http://www.ubuntu.com
>>
>> _______________________________________________
>> lxc-users mailing list
>> lxc-users at lists.linuxcontainers.org
>> http://lists.linuxcontainers.org/listinfo/lxc-users
>>
>
>
>
> --
> benoit barthelet
> http://pgp.mit.edu/pks/lookup?op=get&search=0xF150E01A72F6D2EE
>



-- 
benoit barthelet
http://pgp.mit.edu/pks/lookup?op=get&search=0xF150E01A72F6D2EE
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