[lxc-devel] [PATCH] python: Update to the device related functions

[Serge Hallyn]

Quoting Stéphane Graber (stgraber at ubuntu.com):
> This commit does the following changes to the python API:
>  - Rename the add_device API call to add_device_node
>  - Adds an extra check that the container is running to add_device_node
>  - Introduces a new add_device_net function
> 
> And the following changes to the lxc-device tool:
>  - Change parser setup to better cope with variable number of arguments
>  - Add support for network devices (currently auto-detected)
>  - Support for different names on the host and in the container
> 
> Signed-off-by: Stéphane Graber <stgraber at ubuntu.com>

Acked-by: Serge E. Hallyn <serge.hallyn at ubuntu.com>

> ---
>  src/lxc/lxc-device             | 48 ++++++++++++++++++++++++++++++++++--------
>  src/python-lxc/lxc/__init__.py | 26 +++++++++++++++++++++--
>  2 files changed, 63 insertions(+), 11 deletions(-)
> 
> diff --git a/src/lxc/lxc-device b/src/lxc/lxc-device
> index 467df17..db9399d 100644
> --- a/src/lxc/lxc-device
> +++ b/src/lxc/lxc-device
> @@ -42,24 +42,54 @@ gettext.textdomain("lxc-device")
>  parser = argparse.ArgumentParser(description=_("LXC: Manage devices"),
>                                   formatter_class=argparse.RawTextHelpFormatter)
>  
> +# Global arguments
>  parser.add_argument("-n", dest="container", metavar="CONTAINER",
> -                    help=_("Container to add the device to"), required=True)
> +                    help=_("Name of the container to add the device to"),
> +                    required=True)
>  
> -parser.add_argument("--add", action="append", default=[], metavar="DEVICE",
> -                    help=_("Add a device"), required=True)
> +# Commands
> +subparsers = parser.add_subparsers()
> +subparser_add = subparsers.add_parser('add', help=_('Add a device'))
> +subparser_add.set_defaults(action="add")
> +
> +subparser_add.add_argument(dest="device", metavar="DEVICE",
> +                           help=_("Add a device "
> +                                  "(path to a node or interface name)"))
> +
> +subparser_add.add_argument(dest="name", metavar="NAME", nargs="?",
> +                           help=_("Use an alternative path or name "
> +                                  "in the container"))
>  
>  args = parser.parse_args()
>  
> -# The user needs to be uid 0
> +# Some basic checks
> +if not hasattr(args, "action"):
> +    parser.error(_("You must specify an action."))
> +
> +## The user needs to be uid 0
>  if not os.geteuid() == 0:
>      parser.error(_("You must be root to run this script. Try running: sudo %s"
>                     % (sys.argv[0])))
>  
> +## Don't rename if no alternative name
> +if not args.name:
> +    args.name = args.device
> +
> +## Check that the container is ready
>  container = lxc.Container(args.container)
>  if not container.running:
> -    print("The container must be running.")
> -    sys.exit(1)
> +    parser.error("The container must be running.")
> +
> +# Do the work
> +if args.action == "add":
> +    if os.path.exists("/sys/class/net/%s/" % args.device):
> +        ret = container.add_device_net(args.device, args.name)
> +    else:
> +        ret = container.add_device_node(args.device, args.name)
>  
> -for device in args.add:
> -    container.add_device(device)
> -    print("Added '%s' to '%s'." % (device, container.name))
> +    if ret:
> +        print("Added '%s' to '%s' as '%s'." %
> +              (args.device, container.name, args.name))
> +    else:
> +        print("Failed to add '%s' to '%s' as '%s'." %
> +              (args.device, container.name, args.name))
> diff --git a/src/python-lxc/lxc/__init__.py b/src/python-lxc/lxc/__init__.py
> index 78852ec..cde4fd1 100644
> --- a/src/python-lxc/lxc/__init__.py
> +++ b/src/python-lxc/lxc/__init__.py
> @@ -154,11 +154,14 @@ class Container(_lxc.Container):
>          _lxc.Container.__init__(self, name)
>          self.network = ContainerNetworkList(self)
>  
> -    def add_device(self, path, destpath=None):
> +    def add_device_node(self, path, destpath=None):
>          """
> -            Add device to running container.
> +            Add block/char device to running container.
>          """
>  
> +        if not self.running:
> +            return False
> +
>          if not destpath:
>              destpath = path
>  
> @@ -214,6 +217,25 @@ class Container(_lxc.Container):
>  
>          return True
>  
> +    def add_device_net(self, name, destname=None):
> +        """
> +            Add network device to running container.
> +        """
> +
> +        if not self.running:
> +            return False
> +
> +        if not destname:
> +            destname = name
> +
> +        if not os.path.exists("/sys/class/net/%s/" % name):
> +            return False
> +
> +        return subprocess.call(['ip', 'link', 'set',
> +                                'dev', name,
> +                                'netns', str(self.init_pid),
> +                                'name', destname]) == 0
> +
>      def append_config_item(self, key, value):
>          """
>              Append 'value' to 'key', assuming 'key' is a list.
> -- 
> 1.8.0
> 
> 
> ------------------------------------------------------------------------------
> LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial
> Remotely access PCs and mobile devices and provide instant support
> Improve your efficiency, and focus on delivering more value-add services
> Discover what IT Professionals Know. Rescue delivers
> http://p.sf.net/sfu/logmein_12329d2d
> _______________________________________________
> Lxc-devel mailing list
> Lxc-devel at lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/lxc-devel