SVGHMI: Prepare accepting multiple clients on multiple HMI: Use POULibrary new capability to add variables to PLC Configuration. Now heartbeat and HMI tree root are added by the library part of SVGHMI, and not by each instance.
#!/usr/bin/env python
# -*- coding: utf-8 -*-
from __future__ import absolute_import
from __future__ import print_function
import traceback
import sys
from runtime.Worker import worker
MainWorker = worker()
_PLCObjectSingleton = None
def GetPLCObjectSingleton():
assert _PLCObjectSingleton is not None
return _PLCObjectSingleton
def LogMessageAndException(msg, exp=None):
if exp is None:
exp = sys.exc_info()
if _PLCObjectSingleton is not None:
_PLCObjectSingleton.LogMessage(0, msg + '\n'.join(traceback.format_exception(*exp)))
print(msg)
traceback.print_exception(*exp)
def CreatePLCObjectSingleton(*args, **kwargs):
global _PLCObjectSingleton
from runtime.PLCObject import PLCObject # noqa # pylint: disable=wrong-import-position
_PLCObjectSingleton = PLCObject(*args, **kwargs)
def default_evaluator(tocall, *args, **kwargs):
try:
res = (tocall(*args, **kwargs), None)
except Exception:
res = (None, sys.exc_info())
return res