Dealing with the Python Time Module From Rocket MV Basic

September 2, 2020

Part 2 of 3

In the previous post “Dealing with Internal and Display format data in your MV database with Python” I showed how it is possible to convert the Python date to the MV internal format. We will now show how we can get the Python time date representation. In the time.time() function returns the number of seconds since the Epoch. The Epoch is a system defined date.

python> time.asctime(time.gmtime(0))
'Thu Jan  1 00:00:00 1970'

By having the number of seconds from a specified point in time, we are able to generate a display value that has both the time and the date. This is different than what MV provides, which is q date value and a separate time value.

What we now need to show is how to get the Python time values into an MV BASIC program.

The first thing we need is a module that contains the functions we want to expose to the MV BASIC programmer.

python_time.py
# Example module used in article that describes how to get the Python
# time/date from a MV BASIC program.
import time
def gettime( ):
    “””gettime( ) – returns the number of seconds from Epoch”””
    now = int(time.time())
    return now
def localtime( now ):
    “””localtime( now ) – takes an integer that represents the seconds
                        since Epoch and converts it into a display format”””
    theLocalTime = time.localtime(now)
    d = ( time.asctime(theLocalTime) )
    return d
def getepoch( outtime ):
   “””getepoch( outtime ) – takes a display formatted date/time and returns
                            the number of seconds since the Epoch”””
   itime = time.strptime( outtime )
   epochtime = time.mktime( itime )
   return epochtime

Note that if we run the functions from Python, you see we can get the time is seconds, convert it to a display format, and get the time in seconds from the display format:

python>
import python_time
python> python_time.gettime()
1418144928
python> python_time.localtime(1418144928)
‘Tue Dec 9 09:08:48 2014’
python> python_time.getepoch(‘Tue Dec 9 09:08:48 2014’)
1418144928.0

To access the Python module from MV BASIC we will need to import the module into the current session.

001: ModuleName = “python_time”
002: * import the module
003: pymodule = PyImport(ModuleName)

Note that the U2 Python API provides several @ variables to access any Python exception information of the last executed Python method/function.

029: CHECK_ERROR:
030: IF @PYEXCEPTIONTYPE NE ” THEN
031:  PRINT “EXCEPTION TYPE IS ” :@PYEXCEPTIONTYPE
032:  PRINT “EXCEPTION MESSAGE IS ” :@PYEXCEPTIONMSG
033:  PRINT “EXCEPTIONTRACEBACK IS ” :@PYEXCEPTIONTRACEBACK
034:  STOP “ENDING AT EXECPTION”
035: END
036: RETURN

To call the Python function, we need to set a variable with the function name, and pass it into the U2 Basic pyCallFunction:

006: * call the Python function
007 FuncName = “gettime”
008: pyresult = PyCallFunction(ModuleName, FuncName)
009: GOSUB CHECK_ERROR
010: PRINT “Python RESULT: “
011: PRINT “python time= ” :pyresult

In the above example once we verified there were no raised exceptions, we display the results:

Python RESULT:
python time= 1418146039