Running specific views.py method on django_cron

Question

I have this method on my views.py file:

def getHistoricRates():
    """ Here we have the function that will retrieve the historical rates from fixer.io, since last month """
    rates = {}
    response = urlopen('http://data.fixer.io/api/2018-12-31?access_key=c2f5070ad78b0748111281f6475c0bdd')
    data = response.read()
    rdata = json.loads(data.decode(), parse_float=float) 
    rates_from_rdata = rdata.get('rates', {})
    for rate_symbol in ['USD', 'GBP', 'HKD', 'AUD', 'JPY', 'SEK', 'NOK', 'EUR']:
        try:
            rates[rate_symbol] = rates_from_rdata[rate_symbol]
        except KeyError:
            logging.warning('rate for {} not found in rdata'.format(rate_symbol)) 
            pass

    return rates

@require_http_methods(['GET', 'POST'])
def historical(request):
    date_str = "2018-12-31"
    if datetime.datetime.strptime(date_str,"%Y-%m-%d").weekday()<5:
        rates = getHistoricRates()
        fixerio_rates = [Fixerio_rates(currency=currency, rate=rate)
                     for currency, rate in rates.items()]
        Fixerio_rates.objects.bulk_create(fixerio_rates) 
        return render(request, 'historical.html') 

I want to run historical at 9am every day, except for weekends.

Now, I can't find any example on how to run an existent method, or how to call it from the cron.py file whatsoever.

I do have everything configured, for django_cron but I just can't figure out how to "use" this method from my cron file to run it at specific times.

This is my cron.py file so far:

from django_cron import CronJobBase, Schedule
from .views import historical

class MyCronJob(CronJobBase):
    RUN_AT_TIMES = ['9:00']

    schedule = Schedule(run_at_times=RUN_AT_TIMES)
    code = 'fixerio.my_cron_job'    # a unique code

    def do(self):
        pass    # do your thing here

The name fixerio is my app's name.

Any ideas on this?

Answer 1

Since you're looking to call the getHistoricRates() and the bulk_create() logic from both your historical() view and also a cron job, it would be better to first refactor that common code from the view into a separate module - for example into helpers.py that lives alongside the views.py and cron.py.

helpers.py

from .models import Fixerio_rates

def create_rates():
    rates = getHistoricRates()
    fixerio_rates = [Fixerio_rates(currency=currency, rate=rate)
                     for currency, rate in rates.items()]
    Fixerio_rates.objects.bulk_create(fixerio_rates) 

def getHistoricRates():
    ...

You can then invoke that from your cron job:

cron.py

from .helpers import create_rates

class MyCronJob(CronJobBase):
    RUN_AT_TIMES = ['9:00']

    schedule = Schedule(run_at_times=RUN_AT_TIMES)
    code = 'fixerio.my_cron_job'    # a unique code

    def do(self):
        create_rates()

And also from your view:

views.py

from .helpers import create_rates

@require_http_methods(['GET', 'POST'])
def historical(request):
    date_str = "2018-12-31"
    if datetime.datetime.strptime(date_str,"%Y-%m-%d").weekday()<5:
        create_rates()
        return render(request, 'historical.html')