Using isoformat is neglecting seconds with zero value-CodePudding

I am receiving a datetime string which I am converting into python datetime. My objective was to add 1 second to this datetime.

def modify_date_by_1_second(date):
    if date!="":
        try:
            date_time_obj = datetime.strptime(date, '%Y-%m-%dT%H:%M:%S.%fZ')
            date_time_obj = date_time_obj   timedelta(seconds=1)
            return date_time_obj.isoformat()[:-3] 'Z'
        except Exception as e:
            return None  
    else:
        return None

The above function gives result:

Passed Case:

Input = "2017-09-15T18:30:15.000Z"
Output = "2017-09-15T18:30:16.000Z"

Failed Case:

Input = "2017-09-15T18:30:00.000Z"
Output = "2017-09-15T18:30Z"

I checked by printing the date_time_obj object, it outputs datetime.datetime(2017, 12, 29, 18, 30)

Here seconds are not mentioned.

Is there any way to achieve this for this specific kind of input?

CodePudding user response：

It is YOU that is stripping the seconds off, with your [:-3].

Per the documentation, the .isoformat method does not include the microseconds if the value is 0. Perhaps you need to check the length of the string before you whack off your characters.

Just to elaborate, if the datetime value includes any microseconds at all, the return is

2017-09-15T18:30:15.000001

Which you truncate to:

2017-09-15T18:30:15.000Z

But if the microseconds value is zero, isoformst returns this:

2017-09-15T18:30:15

which you truncate to

2017-09-15T18:30Z