ifupdown2/addons/usercmds.py

   1 #!/usr/bin/python
   2 #
   3 # Copyright 2014 Cumulus Networks, Inc. All rights reserved.
   4 # Author: Roopa Prabhu, roopa@cumulusnetworks.com
   5 #
   6
   7 import subprocess
   8 import ifupdownaddons
   9
  10 class usercmds(ifupdownaddons.modulebase.moduleBase):
  11     """  ifupdown2 addon module to configure user specified commands """
  12
  13     _modinfo = {'mhelp' : 'user commands for interfaces',
  14                 'attrs' : {
  15                    'pre-up' :
  16                         {'help' : 'run command before bringing the interface up'},
  17                    'up' :
  18                         {'help' : 'run command at interface bring up'},
  19                    'post-up' :
  20                         {'help' : 'run command after interface bring up'},
  21                    'pre-down' :
  22                         {'help' : 'run command before bringing the interface down'},
  23                    'down' :
  24                         {'help' : 'run command at interface down'},
  25                    'post-down' :
  26                         {'help' : 'run command after bringing interface down'}}}
  27
  28     def _exec_user_cmd(self, cmd):
  29         """ exec's commands using subprocess Popen
  30
  31         special wrapper using use closefds=True and shell=True
  32         for user commands
  33         """
  34
  35         cmd_returncode = 0
  36         try:
  37             self.logger.info('executing %s' %cmd)
  38             if self.DRYRUN:
  39                 return
  40             ch = subprocess.Popen(cmd,
  41                     stdout=subprocess.PIPE,
  42                     shell=True,
  43                     stderr=subprocess.STDOUT,
  44                     close_fds=True)
  45             cmd_returncode = ch.wait()
  46             cmdout = ch.communicate()[0]
  47         except Exception, e:
  48             raise Exception('failed to execute cmd \'%s\' (%s)'
  49                             %(cmd, str(e)))
  50         if cmd_returncode != 0:
  51             raise Exception(cmdout)
  52         return cmdout
  53
  54     def _run_command(self, ifaceobj, op):
  55         cmd_list = ifaceobj.get_attr_value(op)
  56         if cmd_list:
  57             for cmd in cmd_list:
  58                 self.logger.info('executing cmd \'%s\'' %cmd)
  59                 try:
  60                     self._exec_user_cmd(cmd)
  61                 except Exception, e:
  62                     if not self.ignore_error(str(e)):
  63                         self.logger.warn('%s: %s cmd \'%s\' failed (%s)'
  64                                 %(ifaceobj.name, op, cmd, str(e).strip('\n')))
  65                     pass
  66
  67     _run_ops = {'pre-up' : _run_command,
  68                'pre-down' : _run_command,
  69                'up' : _run_command,
  70                'post-up' : _run_command,
  71                'down' : _run_command,
  72                'post-down' : _run_command}
  73
  74     def get_ops(self):
  75         """ returns list of ops supported by this module """
  76         return self._run_ops.keys()
  77
  78     def run(self, ifaceobj, operation, query_ifaceobj=None, **extra_args):
  79         """ run user commands
  80
  81         Args:
  82             **ifaceobj** (object): iface object
  83
  84             **operation** (str): list of ops
  85
  86         Kwargs:
  87             **query_ifaceobj** (object): query check ifaceobject. This is only
  88                 valid when op is 'query-checkcurr'. It is an object same as
  89                 ifaceobj, but contains running attribute values and its config
  90                 status. The modules can use it to return queried running state
  91                 of interfaces. status is success if the running state is same
  92                 as user required state in ifaceobj. error otherwise.
  93         """
  94         op_handler = self._run_ops.get(operation)
  95         if not op_handler:
  96             return
  97         op_handler(self, ifaceobj, operation)