sfa/nitos/nitosshell.py

   1 import sys
   2 import xmlrpclib
   3 import socket
   4 from urlparse import urlparse
   5
   6 from sfa.util.sfalogging import logger
   7
   8 class NitosShell:
   9     """
  10     A simple xmlrpc shell to a myplc instance
  11     This class can receive all NITOS API  calls to the underlying testbed
  12     For safety this is limited to a set of hard-coded calls
  13     """
  14
  15     direct_calls = ['getNodes','getChannels','getSlices','getUsers','getReservedNodes',
  16                     'getReservedChannels','getTestbedInfo'
  17                     'reserveNodes','reserveChannels','addSlice','addUser','addUserToSlice',
  18                     'addUserKey','addNode', 'addChannel',
  19                     'updateReservedNodes','updateReservedChannels','updateSlice','updateUser',
  20                     'updateNode', 'updateChannel',
  21                     'deleteNode','deleteChannel','deleteSlice','deleteUser', 'deleteUserFromSLice',
  22                     'deleteKey', 'releaseNodes', 'releaseChannels'
  23                     ]
  24
  25
  26     # use the 'capability' auth mechanism for higher performance when the PLC db is local
  27     def __init__ ( self, config ) :
  28         url = config.SFA_NITOS_URL
  29 #        url = "http://195.251.17.239:8080/RPC2"
  30         # try to figure if the url is local
  31         hostname=urlparse(url).hostname
  32         is_local=False
  33         if hostname == 'localhost': is_local=True
  34         # otherwise compare IP addresses;
  35         # this might fail for any number of reasons, so let's harden that
  36         try:
  37             # xxx todo this seems to result in a DNS request for each incoming request to the AM
  38             # should be cached or improved
  39             url_ip=socket.gethostbyname(hostname)
  40             local_ip=socket.gethostbyname(socket.gethostname())
  41             if url_ip==local_ip: is_local=True
  42         except:
  43             pass
  44
  45         if is_local:
  46             try:
  47                 # too bad this is not installed properly
  48                 plcapi_path="/usr/share/plc_api"
  49                 if plcapi_path not in sys.path: sys.path.append(plcapi_path)
  50                 import PLC.Shell
  51                 plc_direct_access=True
  52             except:
  53                 plc_direct_access=False
  54         if is_local and plc_direct_access:
  55             logger.debug('plshell access - capability')
  56             #self.plauth = { 'AuthMethod': 'capability',
  57             #                'Username':   config.SFA_PLC_USER,
  58             #                'AuthString': config.SFA_PLC_PASSWORD,
  59             #                }
  60             self.proxy = PLC.Shell.Shell ()
  61
  62         else:
  63             logger.debug('nitosshell access - xmlrpc')
  64             #self.plauth = { 'AuthMethod': 'password',
  65             #                'Username':   config.SFA_PLC_USER,
  66             #                'AuthString': config.SFA_PLC_PASSWORD,
  67             #                }
  68             self.proxy = xmlrpclib.Server(url, verbose = False, allow_none = True)
  69
  70     def __getattr__(self, name):
  71         def func(*args, **kwds):
  72             actual_name=None
  73             if name in NitosShell.direct_calls: actual_name=name
  74 #            if name in NitosShell.alias_calls: actual_name=NitosShell.alias_calls[name]
  75             if not actual_name:
  76                 raise Exception, "Illegal method call %s for NITOS driver"%(name)
  77             actual_name = "scheduler.server." + actual_name
  78             result=getattr(self.proxy, actual_name)(*args, **kwds)
  79             logger.debug('NitosShell %s (%s) returned ... '%(name,actual_name))
  80             return result
  81         return func
  82