[Kimchi-devel] [PATCH 1/4] bug fix: Identify update tool based on available system tools

[Paulo Ricardo Paz Vital]

Even with the nested try-exception code, I'm OK with this patch :-D
-- 
Reviewed-by: Paulo Vital <pvital at linux.vnet.ibm.com>


On Tue, 2014-03-11 at 17:34 -0300, Aline Manera wrote:
> From: Aline Manera <alinefm at br.ibm.com>
> 
> Instead of using platform.linux_distribution() and keep a list of possible
> values to match, this patch verifies the tools on the system to identify
> which update tool to use in Kimchi.
> So try to import yum module, apt module or run the zypper command and in
> last case raise an error.
> 
> Signed-off-by: Aline Manera <alinefm at br.ibm.com>
> ---
>  src/kimchi/swupdate.py |   33 ++++++++++++++++-----------------
>  1 file changed, 16 insertions(+), 17 deletions(-)
> 
> diff --git a/src/kimchi/swupdate.py b/src/kimchi/swupdate.py
> index 2c2713a..ff5c9d1 100644
> --- a/src/kimchi/swupdate.py
> +++ b/src/kimchi/swupdate.py
> @@ -17,7 +17,6 @@
>  # License along with this library; if not, write to the Free Software
>  # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
> 
> -import platform
>  import subprocess
>  import time
> 
> @@ -25,11 +24,6 @@ from kimchi.basemodel import Singleton
>  from kimchi.exception import NotFoundError, OperationFailed
>  from kimchi.utils import kimchi_log, run_command
> 
> -YUM_DISTROS = ['fedora', 'red hat enterprise linux',
> -               'red hat enterprise linux server']
> -APT_DISTROS = ['debian', 'ubuntu']
> -ZYPPER_DISTROS = ['opensuse ', 'suse linux enterprise server ']
> -
> 
>  class SoftwareUpdate(object):
>      __metaclass__ = Singleton
> @@ -51,19 +45,24 @@ class SoftwareUpdate(object):
> 
>          # Get the distro of host machine and creates an object related to
>          # correct package management system
> -        self._distro = platform.linux_distribution()[0].lower()
> -        if (self._distro in YUM_DISTROS):
> +        try:
> +            __import__('yum')
>              kimchi_log.info("Loading YumUpdate features.")
>              self._pkg_mnger = YumUpdate()
> -        elif (self._distro in APT_DISTROS):
> -            kimchi_log.info("Loading AptUpdate features.")
> -            self._pkg_mnger = AptUpdate()
> -        elif (self._distro in ZYPPER_DISTROS):
> -            kimchi_log.info("Loading ZypperUpdate features.")
> -            self._pkg_mnger = ZypperUpdate()
> -        else:
> -            raise Exception("There is no compatible package manager for "
> -                            "this system.")
> +        except ImportError:
> +            try:
> +                __import__('apt')
> +                kimchi_log.info("Loading AptUpdate features.")
> +                self._pkg_mnger = AptUpdate()
> +            except ImportError:
> +                zypper_help = "zypper --help"
> +                (stdout, stderr, returncode) = run_command(zypper_help)
> +                if returncode == 0:
> +                    kimchi_log.info("Loading ZypperUpdate features.")
> +                    self._pkg_mnger = ZypperUpdate()
> +                else:
> +                    raise Exception("There is no compatible package manager "
> +                                    "for this system.")
> 
>      def _scanUpdates(self):
>          """