ed@448: #!/usr/bin/env python
ed@448: # -*- coding: utf-8 -*-
ed@448: #
ed@448: #Copyright (C) 2007: Edouard TISSERANT and Laurent BESSARD
ed@448: #
ed@448: #See COPYING file for copyrights details.
ed@448: #
ed@448: #This library is free software; you can redistribute it and/or
ed@448: #modify it under the terms of the GNU General Public
ed@448: #License as published by the Free Software Foundation; either
ed@448: #version 2.1 of the License, or (at your option) any later version.
ed@448: #
ed@448: #This library is distributed in the hope that it will be useful,
ed@448: #but WITHOUT ANY WARRANTY; without even the implied warranty of
ed@448: #MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
ed@448: #General Public License for more details.
ed@448: #
ed@448: #You should have received a copy of the GNU General Public
ed@448: #License along with this library; if not, write to the Free Software
ed@448: #Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
ed@448: import traceback
ed@448: 
ed@448: 
ed@448: def LPC_connector_factory(uri, pluginsroot):
ed@448:     """
ed@448:     This returns the connector to LPC style PLCobject
ed@448:     """
ed@448:     pluginsroot.logger.write(_("Connecting to URI : %s\n")%uri)
ed@448: 
ed@448:     servicetype, location = uri.split("://")
ed@448:     
ed@448:     # Try to get the proxy object
ed@448:     try :
ed@448:         # TODO: Open Serial Port
ed@448:         RemotePLCObjectProxy = LPCObject(pluginsroot) # LPC_PLCObject_Proxy
ed@448:     except Exception, msg:
ed@448:         pluginsroot.logger.write_error(_("Couldn't connect !\n"))
ed@448:         pluginsroot.logger.write_error(traceback.format_exc())
ed@448:         return None
ed@448: 
ed@448:     def LPCCatcher(func, default=None):
ed@448:         """
ed@448:         A function that catch a pyserial exceptions, write error to logger
ed@448:         and return defaul value when it happen
ed@448:         """
ed@448:         def catcher_func(*args,**kwargs):
ed@448:             try:
ed@448:                 return func(*args,**kwargs)
ed@448:             except Exception,e:
ed@448:                 #pluginsroot.logger.write_error(traceback.format_exc())
ed@448:                 pluginsroot.logger.write_error(str(e)+"\n")
ed@448:                 pluginsroot._connector = None
ed@448:                 return default
ed@448:         return catcher_func
ed@448: 
ed@448:     # Check connection is effective. 
ed@448:     # lambda is for getattr of GetPLCstatus to happen inside catcher
ed@448:     if LPCCatcher(lambda:RemotePLCObjectProxy.GetPLCstatus())() == None:
ed@448:         pluginsroot.logger.write_error(_("Cannot get PLC status - connection failed.\n"))
ed@448:         return None
ed@448: 
ed@448: 
ed@448:     class LPCProxy:
ed@448:         """
ed@448:         A Serial proxy class to handle Beremiz Pyro interface specific behavior.
ed@448:         And to put LPC exception catcher in between caller and pyro proxy
ed@448:         """
ed@448:         def _LPCGetTraceVariables(self):
ed@448:             return self.RemotePLCObjectProxy.GetTraceVariables()
ed@448:         GetTraceVariables = LPCCatcher(_LPCGetTraceVariables,("Broken",None,None))
ed@448: 
ed@448:         def _LPCGetPLCstatus(self):
ed@448:             return RemotePLCObjectProxy.GetPLCstatus()
ed@448:         GetPLCstatus = LPCCatcher(_LPCGetPLCstatus, "Broken")
ed@448:         
ed@448:         def __getattr__(self, attrName):
ed@448:             member = self.__dict__.get(attrName, None)
ed@448:             if member is None:
ed@448:                 def my_local_func(*args,**kwargs):
ed@448:                     return RemotePLCObjectProxy.__getattr__(attrName)(*args,**kwargs)
ed@448:                 member = LPCCatcher(my_local_func, None)
ed@448:                 self.__dict__[attrName] = member
ed@448:             return member
ed@448: 
ed@448:     return LPCProxy()
ed@448:     
ed@448: