SVGHMI: JsonTable now use intermediate variables again to address JSON data without duplicating code or referencing. Using intermediate variables also alows to check for availability of data and stop evaluating early if data is missing. Finally added complete roundtrip example to illustrate use of JSonTable to display "alarms" collected in python from changes on PLC boolean variables.
#!/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