Python / Django interval of hours

Question

I need to create a schedule of hours:

I have the following information in the Django template:

Initial time: 08:00

Final time: 18:00

Break in minutes 00:30

I would have been able to implement something like:

for hora in range(hrInicial, hrFinal, intervalo):
      print(hora)

08:00
08:30
09:00
09:30
...

This would be the parameterization to create the agenda, for this reason I do not have the date, only the time. The idea is to register for each day of the week a specific period. Ex.:

Segunda - 08:00 as 12:00
Terça   - 08:00 as 18:00
Quarta  - 12:00 as 18:00
...

In the template considering the 30 minute interval to Monday, I want to display:

08:00
08:30
09:00
09:30
10:00
10:30
11:00
11:30
12:00

I researched the similar questions, but for Python, I did not find similar question.

Thank you for the force.

Answer 1

You can use the module datetime, with the guys datetime, timedelta and time. The only detail is that you will need to inform a date, that is, year, month and day, however, as we are only interested in the time, any valid date will be possible, because in the end it will be disregarded. In this example, I used the date 01/01/2017.

The logic is as follows: you can create an object of type datetime as follows

>>> from datetime import datetime, timedelta, time
>>> hrInicial = datetime(2017, 1, 1, 8, 0, 0)

Note that I had to inform the date initially and after, I informed the time, 8, minutes, 0, and seconds, 0. I can check if the time was set correctly by doing:

>>> print(hrInicial.time())
08:00:00

To add a time interval, we use the type timedelta. For a 30-minute break, we do:

>>> intervalo = timedelta(minutes=30)

We can add this interval to the initial time with the same sum operator:

>>> novaHora = hrInicial + intervalo
>>> print(novaHora.time())
08:30:00

Note that the time has been incremented as expected. Using this logic, we can create a generic function:

def get_interval (inicio, fim, intervalo):

    """ 
    Retorna a lista de horários entre `inicio` e `fim`, inclusive, com um intervalo definido por `intervalo`.

    @param inicio    iterable Lista de três valores no formato (hora, minutos, segundos)
    @param fim       iterable Lista de três valores no formato (hora, minutos, segundos)
    @param intervalo iterable Lista de três valores no formato (hora, minutos, segundos)
    @return generator
    """

    inicio = datetime(2017, 1, 1, *inicio)
    fim = datetime(2017, 1, 1, *fim)

    iHoras, iMinutos, iSegundos = intervalo

    intervalo = timedelta(hours=iHoras, minutes=iMinutos, seconds=iSegundos)

    while inicio <= fim:
        yield inicio.time()
        inicio += intervalo

The parameters will be a list of three values: the first defines the hours, the second the minutes and the third the seconds. This way, we can do:

>>> hrInicial = (8, 0, 0)
>>> hrFinal   = (12, 0, 0)
>>> intervalo = (0, 30, 0)
>>> for hora in get_interval(hrInicial, hrFinal, intervalo):
...     print(hora)
08:00:00
08:30:00
09:00:00
09:30:00
10:00:00
10:30:00
11:00:00
11:30:00
12:00:00

See working on Ideone.