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))
[-------------------------------------------------------------]
<?xml version='1.0' encoding='utf-8'?>
<PyFile xmlns:xhtml="http://www.w3.org/1999/xhtml">
<variables>
<variable name="Power_ON" type="BOOL"/>
<variable name="Power_OFF" type="BOOL"/>
<variable name="DrawTest" type="BOOL"/>
<variable name="DrawLogo" type="BOOL"/>
<variable name="DrawEscher" type="BOOL"/>
<variable name="Detect_Circle" type="BOOL"/>
<variable name="XaxisPos" type="INT"/>
<variable name="YaxisPos" type="INT"/>
<variable name="ZaxisPos" type="INT"/>
<variable name="TaxisPos" type="INT"/>
<variable name="XaxisMinus" type="BOOL"/>
<variable name="YaxisMinus" type="BOOL"/>
<variable name="ZaxisMinus" type="BOOL"/>
<variable name="TaxisMinus" type="BOOL"/>
<variable name="XaxisPlus" type="BOOL"/>
<variable name="YaxisPlus" type="BOOL"/>
<variable name="ZaxisPlus" type="BOOL"/>
<variable name="TaxisPlus" type="BOOL"/>
<variable name="DrawTestBtn" type="BOOL"/>
<variable name="DrawTestBtn2" type="BOOL"/>
</variables>
<globals>
<xhtml:p><![CDATA[
import ctypes
import wx, sys
AxisList = ["X","Y","Z","T"]
PwrButtons = ['Power_ON',
'Power_OFF']
ActionButtons = ['Detect_Circle',
'DrawTest',
'DrawLogo',
'DrawEscher']
class ThreeDee(wx.StaticText):
def __init__(self, *args, **kwargs):
self.initialized = False
kwargs["style"] = wx.ALIGN_CENTRE_HORIZONTAL
super(ThreeDee, self).__init__(*args, **kwargs)
self.SetFont(wx.Font(24, wx.SWISS, wx.NORMAL, wx.BOLD))
self.positions = [0.]*4
self.Message = None
self.NegLimits = None
self.Disk = None
def UpdatePositions(self, positions):
# get globals from PLC
self.positions = positions
self.SetLabel(
((self.Message +'\n\n') if self.Message else '' )+
" ".join(["%s %+.2f"%(axis,self.positions[i])
for i,axis in enumerate(AxisList)]))
def MakeButtonFunc(window, sizer, btname):
def ButtonDown(event):
setattr(PLCGlobals,btname,1)
event.Skip()
def ButtonUp(event):
setattr(PLCGlobals,btname,0)
event.Skip()
obj = wx.BitmapButton(window, -1, wx.Bitmap('%s.png'%btname))
sizer.Add(obj, 2, wx.EXPAND, 0)
obj.Bind(wx.EVT_LEFT_DOWN, ButtonDown)
obj.Bind(wx.EVT_LEFT_UP, ButtonUp)
return obj
def UpdPos(self):
positions = [getattr(PLCGlobals,axname+"axisPos") for axname in AxisList]
self.window_1.UpdatePositions(positions)
Class_wxglade_hmi.UpdPos = UpdPos
#def UpdatePositions(self, event):
#
# positions = [getattr(PLCGlobals,axname+"axisPos") for axname in AxisList]
#
# self.window_1.UpdatePositions(positions)
#
# event.Skip()
#Class_wxglade_hmi.UpdatePositions = UpdatePositions
initorig = Class_wxglade_hmi.__init__
def Init(self,*args,**kargs):
initorig(self,*args,**kargs)
sizer = self.GetSizer().GetItem(1).GetSizer().GetItem(0).GetSizer()
self.main_buttons = map(
lambda btname: MakeButtonFunc(self, sizer, btname), PwrButtons)
sizer = self.GetSizer().GetItem(1).GetSizer().GetItem(1).GetSizer()
self.main_buttons = map(
lambda btname: MakeButtonFunc(self, sizer, btname), ActionButtons)
self.axis_buttons = map(
lambda axis:( MakeButtonFunc(self, sizer, axis+"axisMinus"),
MakeButtonFunc(self, sizer, axis+"axisPlus")),
AxisList)
# self.timer = wx.Timer(self, -1)
# self.Bind(wx.EVT_TIMER, self.UpdatePositions, self.timer)
# self.ShowFullScreen(True,wx.FULLSCREEN_ALL)
# wx.CallAfter(self.timer.Start,200)
Class_wxglade_hmi.__init__ = Init
def SetPLCTestBtnGlobalVar(self, evt):
setattr(PLCGlobals, "DrawTestBtn", evt.GetEventObject().GetValue())
def SetPLCTestBtn2GlobalVar(self, evt):
setattr(PLCGlobals, "DrawTestBtn2", evt.GetEventObject().GetValue())
]]></xhtml:p>
</globals>
<init>
<xhtml:p><![CDATA[
]]></xhtml:p>
</init>
<cleanup>
<xhtml:p><![CDATA[
]]></xhtml:p>
</cleanup>
<start>
<xhtml:p><![CDATA[
]]></xhtml:p>
</start>
<stop>
<xhtml:p><![CDATA[
]]></xhtml:p>
</stop>
</PyFile>