Calculate session between in and out and total working hours of session

Question

Is there any way to improve this code: punch:0 -> in punch:1 -> out

from datetime import datetime

attendance = [{"id": 1, "punch": 0, "date": "22-04-2022 02:10:00"},
          {"id": 1, "punch": 1, "date": "22-04-2022 03:00:00"},

          {"id": 1, "punch": 1, "date": "22-04-2022 04:00:00"},
          {"id": 1, "punch": 0, "date": "22-04-2022 05:00:00"},

          {"id": 1, "punch": 1, "date": "22-04-2022 06:00:00"},
          {"id": 1, "punch": 1, "date": "22-04-2022 08:00:10"},
          ]

sessions = []
total_hours = datetime.strptime("00:00:00", '%H:%M:%S')
in_time = None
out_time = None
for k in attendance:
if k["punch"].__eq__(0):
    in_time = k["date"]
elif k["punch"].__eq__(1):
    print(k)
    if in_time is not None:
        out_time = k["date"]
        total_hours += datetime.strptime(out_time, '%d-%m-%Y %H:%M:%S') - \
                           datetime.strptime(in_time, '%d-%m-%Y %H:%M:%S')
        sessions.append((in_time, out_time))
        in_time = None
print(sessions, total_hours.time())

output: [('22-04-2022 02:10:00', '22-04-2022 03:00:00'), ('22-04-2022 05:00:00', '22-04-2022 06:00:00')] 01:50:00

Answer 1

Declare the constants your program needs. This helps to document your code and reduce the chance of bugs:

from datetime import datetime, timedelta

PUNCH_IN = 0
PUNCH_OUT = 1
TIME_FORMAT = '%d-%m-%Y %H:%M:%S'

Organize the logic in well-focused functions. Avoid the temptation to do too many things at once. First handle the grouping of punches into start-end pairs. (Since it's a very simple operation, parsing the datetimes can be handled here as well, but if the situation were more complex, delegating the parsing to a separate function would make sense.)

def get_sessions(attendance):
    start = None
    for d in attendance:
        t = datetime.strptime(d['date'], TIME_FORMAT)
        p = d['punch']
        if p == PUNCH_IN:
            start = t
        elif start and p == PUNCH_OUT:
            yield (start, t)
            start = None

Compute the total. With the annoying part out of the way, computing the total is a straightforward sum of timedeltas.

def compute_total_time(sessions):
    return sum(
        (end - start for start, end in sessions),
        timedelta()
    )

def main():
    attendance = [ ... ]
    sessions = tuple(get_sessions(attendance))
    total = compute_total_time(sessions)
    print(total)

if __name__ == '__main__':
    main()