1 #!/usr/bin/env python

     2 # -*- coding: utf-8 -*-

     3 

     4 # This file is part of Beremiz, a Integrated Development Environment for

     5 # programming IEC 61131-3 automates supporting plcopen standard and CanFestival.

     6 #

     7 # Copyright (C) 2007: Edouard TISSERANT and Laurent BESSARD

     8 #

     9 # See COPYING file for copyrights details.

    10 #

    11 # This program is free software; you can redistribute it and/or

    12 # modify it under the terms of the GNU General Public License

    13 # as published by the Free Software Foundation; either version 2

    14 # of the License, or (at your option) any later version.

    15 #

    16 # This program is distributed in the hope that it will be useful,

    17 # but WITHOUT ANY WARRANTY; without even the implied warranty of

    18 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

    19 # GNU General Public License for more details.

    20 #

    21 # You should have received a copy of the GNU General Public License

    22 # along with this program; if not, write to the Free Software

    23 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

    24 

    25 

    26 from time import sleep

    27 import copy

    28 import socket

    29 import os.path

    30 

    31 import Pyro5

    32 import Pyro5.client

    33 import Pyro5.errors

    34 

    35 # TODO: PSK

    36 

    37 import importlib

    38 

    39 

    40 Pyro5.config.SERIALIZER = "msgpack"

    41 

    42 

    43 def PYRO_connector_factory(uri, confnodesroot):

    44     """

    45     This returns the connector to Pyro style PLCobject

    46     """

    47     confnodesroot.logger.write(_("PYRO connecting to URI : %s\n") % uri)

    48 

    49     scheme, location = uri.split("://")

    50 

    51     # TODO: use ssl

    52 

    53     schemename = "PYRO"

    54 

    55     # Try to get the proxy object

    56     try:

    57         RemotePLCObjectProxy = Pyro5.client.Proxy(f"{schemename}:PLCObject@{location}")

    58     except Exception as e:

    59         confnodesroot.logger.write_error(

    60             _("Connection to {loc} failed with exception {ex}\n").format(

    61                 loc=location, ex=str(e)))

    62         return None

    63 

    64     RemotePLCObjectProxy._pyroTimeout = 60

    65 

    66     class MissingCallException(Exception):

    67         pass

    68 

    69     def PyroCatcher(func, default=None):

    70         """

    71         A function that catch a Pyro exceptions, write error to logger

    72         and return default value when it happen

    73         """

    74         def catcher_func(*args, **kwargs):

    75             try:

    76                 return func(*args, **kwargs)

    77             except Pyro5.errors.ConnectionClosedError as e:

    78                 confnodesroot._SetConnector(None)

    79                 confnodesroot.logger.write_error(_("Connection lost!\n"))

    80             except Pyro5.errors.ProtocolError as e:

    81                 confnodesroot.logger.write_error(_("Pyro exception: %s\n") % e)

    82             except MissingCallException as e:

    83                 confnodesroot.logger.write_warning(_("Remote call not supported: %s\n") % e.message)

    84             except Exception as e:

    85                 errmess = ''.join(Pyro5.errors.get_pyro_traceback())

    86                 confnodesroot.logger.write_error(errmess + "\n")

    87                 print(errmess)

    88                 confnodesroot._SetConnector(None)

    89             return default

    90         return catcher_func

    91 

    92     # Check connection is effective.

    93     # lambda is for getattr of GetPLCstatus to happen inside catcher

    94     IDPSK = PyroCatcher(RemotePLCObjectProxy.GetPLCID)()

    95     if IDPSK is None:

    96         confnodesroot.logger.write_warning(_("PLC did not provide identity and security infomation.\n"))

    97     else:

    98         ID, secret = IDPSK

    99         PSK.UpdateID(confnodesroot.ProjectPath, ID, secret, uri)

   100 

   101     class PyroProxyProxy(object):

   102         """

   103         A proxy proxy class to handle Beremiz Pyro interface specific behavior.

   104         And to put Pyro exception catcher in between caller and Pyro proxy

   105         """

   106         def __getattr__(self, attrName):

   107             member = self.__dict__.get(attrName, None)

   108             if member is None:

   109                 def my_local_func(*args, **kwargs):

   110                     call = RemotePLCObjectProxy.__getattr__(attrName)

   111                     if call is None:

   112                         raise MissingCallException(attrName)

   113                     else:

   114                         return call(*args, **kwargs)

   115                 member = PyroCatcher(my_local_func, self.PLCObjDefaults.get(attrName, None))

   116                 self.__dict__[attrName] = member

   117             return member

   118 

   119     return PyroProxyProxy