ifupdown/ifupdownbase.py

   1 #!/usr/bin/python
   2 #
   3 # Copyright 2014 Cumulus Networks, Inc. All rights reserved.
   4 # Author: Roopa Prabhu, roopa@cumulusnetworks.com
   5 #
   6 # ifupdownBase --
   7 #    base object for various ifupdown objects
   8 #
   9
  10 import logging
  11 import subprocess
  12 import re
  13 import os
  14 import rtnetlink_api as rtnetlink_api
  15 import signal
  16 import shlex
  17
  18 from iface import *
  19 from ifupdown.utils import utils
  20
  21
  22 class ifupdownBase(object):
  23
  24     def __init__(self):
  25         modulename = self.__class__.__name__
  26         self.logger = logging.getLogger('ifupdown.' + modulename)
  27
  28     def exec_command(self, cmd, cmdenv=None, nowait=False):
  29         cmd_returncode = 0
  30         cmdout = ''
  31         try:
  32             self.logger.info('executing ' + cmd)
  33             if self.DRYRUN:
  34                 return cmdout
  35             ch = subprocess.Popen(shlex.split(cmd),
  36                     stdout=subprocess.PIPE,
  37                     shell=False, env=cmdenv,
  38                     stderr=subprocess.STDOUT,
  39                     close_fds=True)
  40             utils.enable_subprocess_signal_forwarding(ch, signal.SIGINT)
  41             cmdout = ch.communicate()[0]
  42             cmd_returncode = ch.wait()
  43         except OSError, e:
  44             raise Exception('could not execute ' + cmd +
  45                     '(' + str(e) + ')')
  46         finally:
  47             utils.disable_subprocess_signal_forwarding(signal.SIGINT)
  48         if cmd_returncode != 0:
  49             raise Exception('error executing cmd \'%s\'' %cmd +
  50                 '\n(' + cmdout.strip('\n ') + ')')
  51         return cmdout
  52
  53     def ignore_error(self, errmsg):
  54         if (self.FORCE == True or re.search(r'exists', errmsg,
  55             re.IGNORECASE | re.MULTILINE) is not None):
  56             return True
  57         return False
  58
  59     def log_warn(self, str):
  60         if self.ignore_error(str) == False:
  61             if self.logger.getEffectiveLevel() == logging.DEBUG:
  62                 traceback.print_stack()
  63             self.logger.warn(str)
  64         pass
  65
  66     def log_error(self, str):
  67         if self.ignore_error(str) == False:
  68             raise
  69             #raise Exception(str)
  70         else:
  71             pass
  72
  73     def link_exists(self, ifacename):
  74         return os.path.exists('/sys/class/net/%s' %ifacename)
  75
  76     def link_up(self, ifacename):
  77         rtnetlink_api.rtnl_api.link_set(ifacename, "up")
  78
  79     def link_down(self, ifacename):
  80         rtnetlink_api.rtnl_api.link_set(ifacename, "down")