Django currency

Overview

Simple django app that handles basic currency handling, formatting and manual addition of exchange rates that can be used to easy convert from one currency to another

Example usage

from currency.models import Currency, ExchangeRate, Money

usd = Currency.objects.create(code='USD', short_name=u'$')
eur = Currency.objects.create(code='EUR', short_name=u'€')

ExchangeRate.objects.create(base_currency=usd, foreign_currency=eur, rate=1/1.3)

print(usd.get_rate(eur))  # Decimal('0.76923')
print(eur.get_rate(usd))  # Decimal('1.30000')

my_money = Money(1531, 'USD')
print(my_money)  # 1531.00000USD
my_money += Money(23, 'USD')
print(my_money)  # 1554.00000USD
print(my_money.convert_to('EUR'))  # 1195.38342EUR

# be careful with conversions. Errors accumulate with each conversion. Example:
print(my_money.convert_to('EUR').convert_to('USD'))  # 1553.99845USD


# indirect rates through rates of default currency (USD) are available too
hrn = Currency.objects.create(code='UAH', short_name='hrn')
rub = Currency.objects.create(code='RUB', short_name='rub')

ExchangeRate.objects.create(
    base_currency=default_currency, foreign_currency=hrn,
    rate='0.125')
# get stored value to normalize decimals precision:
rate1 = ExchangeRate.objects.get(
    base_currency=default_currency, foreign_currency=hrn)

ExchangeRate.objects.create(
    base_currency=default_currency, foreign_currency=rub,
    rate='0.03125')
# get stored value to normalize decimals precision:
rate2 = ExchangeRate.objects.get(
    base_currency=default_currency, foreign_currency=rub)

self.assertEqual(hrn.get_rate(rub), rate1.rate / rate2.rate)