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) 2007: Edouard TISSERANT and Laurent BESSARD
# Copyright (C) 2017: Andrey Skvortsov <andrej.skvortzov@gmail.com>
#
# 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 wx
from graphics.GraphicCommons import LEFTRAIL, RIGHTRAIL
from graphics.LD_Objects import LD_PowerRail
from dialogs.BlockPreviewDialog import BlockPreviewDialog
# -------------------------------------------------------------------------------
# Set Ladder Power Rail Parameters Dialog
# -------------------------------------------------------------------------------
class LDPowerRailDialog(BlockPreviewDialog):
"""
Class that implements a dialog for defining parameters of a power rail graphic
element
"""
def __init__(self, parent, controller, tagname):
"""
Constructor
@param parent: Parent wx.Window of dialog for modal
@param controller: Reference to project controller
@param tagname: Tagname of project POU edited
"""
BlockPreviewDialog.__init__(self, parent, controller, tagname,
title=_('Power Rail Properties'))
# Init common sizers
self._init_sizers(2, 0, 5, None, 2, 1)
# Create label for connection type
type_label = wx.StaticText(self, label=_('Type:'))
self.LeftGridSizer.AddWindow(type_label, flag=wx.GROW)
# Create radio buttons for selecting power rail type
self.TypeRadioButtons = {}
first = True
for type, label in [(LEFTRAIL, _('Left PowerRail')),
(RIGHTRAIL, _('Right PowerRail'))]:
radio_button = wx.RadioButton(self, label=label,
style=(wx.RB_GROUP if first else 0))
radio_button.SetValue(first)
self.Bind(wx.EVT_RADIOBUTTON, self.OnTypeChanged, radio_button)
self.LeftGridSizer.AddWindow(radio_button, flag=wx.GROW)
self.TypeRadioButtons[type] = radio_button
first = False
# Create label for power rail pin number
pin_number_label = wx.StaticText(self, label=_('Pin number:'))
self.LeftGridSizer.AddWindow(pin_number_label, flag=wx.GROW)
# Create spin control for defining power rail pin number
self.PinNumber = wx.SpinCtrl(self, min=1, max=50,
style=wx.SP_ARROW_KEYS)
self.PinNumber.SetValue(1)
self.Bind(wx.EVT_SPINCTRL, self.OnPinNumberChanged, self.PinNumber)
self.LeftGridSizer.AddWindow(self.PinNumber, flag=wx.GROW)
# Add preview panel and associated label to sizers
self.RightGridSizer.AddWindow(self.PreviewLabel, flag=wx.GROW)
self.RightGridSizer.AddWindow(self.Preview, flag=wx.GROW)
# Add buttons sizer to sizers
self.MainSizer.AddSizer(
self.ButtonSizer, border=20,
flag=wx.ALIGN_RIGHT | wx.BOTTOM | wx.LEFT | wx.RIGHT)
self.Fit()
# Left Power Rail radio button is default control having keyboard focus
self.TypeRadioButtons[LEFTRAIL].SetFocus()
def GetMinElementSize(self):
"""
Get minimal graphic element size
@return: Tuple containing minimal size (width, height) or None if no
element defined
"""
return self.Element.GetMinSize(True)
def GetPowerRailType(self):
"""
Return type selected for power rail
@return: Type selected (LEFTRAIL or RIGHTRAIL)
"""
return (LEFTRAIL
if self.TypeRadioButtons[LEFTRAIL].GetValue()
else RIGHTRAIL)
def SetValues(self, values):
"""
Set default power rail parameters
@param values: Power rail parameters values
"""
# For each parameters defined, set corresponding control value
for name, value in values.items():
# Parameter is power rail type
if name == "type":
self.TypeRadioButtons[value].SetValue(True)
# Parameter is power rail pin number
elif name == "pin_number":
self.PinNumber.SetValue(value)
def GetValues(self):
"""
Return power rail parameters defined in dialog
@return: {parameter_name: parameter_value,...}
"""
values = {
"type": self.GetPowerRailType(),
"pin_number": self.PinNumber.GetValue()}
values["width"], values["height"] = self.Element.GetSize()
return values
def OnTypeChanged(self, event):
"""
Called when power rail type changed
@param event: wx.RadioButtonEvent
"""
self.RefreshPreview()
event.Skip()
def OnPinNumberChanged(self, event):
"""
Called when power rail pin number value changed
@param event: wx.SpinEvent
"""
self.RefreshPreview()
event.Skip()
def RefreshPreview(self):
"""
Refresh preview panel of graphic element
Override BlockPreviewDialog function
"""
# Set graphic element displayed, creating a power rail element
self.Element = LD_PowerRail(self.Preview,
self.GetPowerRailType(),
connectors=self.PinNumber.GetValue())
# Call BlockPreviewDialog function
BlockPreviewDialog.RefreshPreview(self)