beremiz

Dirty fix for error '_object_has_no_attribute_'getSlave' in EtherCAT extension

2018-08-10, Andrey Skvortsov
a3ac46366b86
Dirty fix for error '_object_has_no_attribute_'getSlave' in EtherCAT extension

traceback:
File "/home/developer/WorkData/PLC/beremiz/beremiz/IDEFrame.py", line 1433, in OnPouSelectedChanged
window.RefreshView()
File "/home/developer/WorkData/PLC/beremiz/beremiz/etherlab/ConfigEditor.py", line 837, in RefreshView
self.RefreshProcessVariables()
File "/home/developer/WorkData/PLC/beremiz/beremiz/etherlab/ConfigEditor.py", line 886, in RefreshProcessVariables
slaves = self.Controler.GetSlaves(**self.CurrentNodesFilter)
File "/home/developer/WorkData/PLC/beremiz/beremiz/etherlab/EthercatMaster.py", line 341, in GetSlaves
for slave in self.Config.getConfig().getSlave():
:_'lxml.etree._Element'_object_has_no_attribute_'getSlave'

Steps to reproduce problem:

- Add new EtherCAT master
- Add new EthercatNode to the master
- double click on


this is looks like dirty hack to fix strange problem with initial[0]
changing its type after returning from _init_ method to lxml.etree._Element
As a result all methods generated by class factory are lost.

For example, in function initMethod initial[0].__class__ points to
xmlclass.xmlclass.Config. After map(self.append, initial)
self.Config.__class__ is 'xmlclass.xmlclass.Config' as well.
But after returning from initMethod (_init) in CreateElement
self.Config.__class__ has changed to lxml.etree._Element.


I've noticed similar behavior if copy/deepcopy is used for any child
of etree.ElementBase. See simple example below.
[-------------------------------------------------------------]
#!/usr/bin/python

from __future__ import print_function
from lxml import etree
import copy

class DefaultElementClass(etree.ElementBase):
def getLocalTag(self):
return etree.QName(self.tag).localname


def printInformation(x):
print(x, x.__class__, "getLocalTag" in dir(x))


a = DefaultElementClass()
printInformation(a)

#
printInformation(copy.copy(a))
printInformation(copy.deepcopy(a))
[-------------------------------------------------------------]
#!/usr/bin/env python
# -*- coding: utf-8 -*-
# This file is part of Beremiz, a Integrated Development Environment for
# programming IEC 61131-3 automates supporting plcopen standard and CanFestival.
#
# Copyright (C) 2012: Edouard TISSERANT and Laurent BESSARD
#
# See COPYING file for copyrights details.
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
from __future__ import absolute_import
import os
import wx
# -------------------------------------------------------------------------------
# Library Structures
# -------------------------------------------------------------------------------
BitmapLibrary = {}
BitmapFolders = []
# -------------------------------------------------------------------------------
# Library Helpers
# -------------------------------------------------------------------------------
def AddBitmapFolder(path):
if os.path.exists(path) and os.path.isdir(path) and path not in BitmapFolders:
BitmapFolders.append(path)
def SearchBitmap(bmp_name):
for folder in BitmapFolders:
bmp_path = os.path.join(folder, bmp_name + ".png")
if os.path.isfile(bmp_path):
return wx.Bitmap(bmp_path)
return None
def GetBitmap(bmp_name1, bmp_name2=None, size=None):
bmp = BitmapLibrary.get((bmp_name1, bmp_name2, size))
if bmp is not None:
return bmp
if bmp_name2 is None:
bmp = SearchBitmap(bmp_name1)
else:
# Bitmap with two icon
bmp1 = SearchBitmap(bmp_name1)
bmp2 = SearchBitmap(bmp_name2)
if bmp1 is not None and bmp2 is not None:
# Calculate bitmap size
width = bmp1.GetWidth() + bmp2.GetWidth() - 1
height = max(bmp1.GetHeight(), bmp2.GetHeight())
# Create bitmap with both icons
bmp = wx.EmptyBitmap(width, height)
dc = wx.MemoryDC()
dc.SelectObject(bmp)
dc.Clear()
dc.DrawBitmap(bmp1, 0, 0)
dc.DrawBitmap(bmp2, bmp1.GetWidth() - 1, 0)
dc.Destroy()
elif bmp1 is not None:
bmp = bmp1
elif bmp2 is not None:
bmp = bmp2
if bmp is not None:
BitmapLibrary[(bmp_name1, bmp_name2, size)] = bmp
return bmp