def get_approx(self, currency, date):
"""
Returns currency rates for the specified date or for the nearest date
if there is no data for the specified date.
"""
if currency == constants.LOCAL_CURRENCY:
return ( Decimal(1), Decimal(1) )
day = util.get_day(date)
today = util.get_day(datetime.date.today())
rates = [ rate for rate in self._db.execute("""
SELECT
day,
sell_rate,
buy_rate
FROM
rates
WHERE
currency = ? AND ? <= day AND day <= ?
""", (currency, day - MIN_RATE_ACCURACY, day + MIN_RATE_ACCURACY)) ]
if (
self._todays_rates is not None and
currency in self._todays_rates and
day - MIN_RATE_ACCURACY <= today <= day + MIN_RATE_ACCURACY
):
rates.append((today,) + self._todays_rates[currency])
nearest = None
for rate in rates:
if nearest is None or abs(day - rate[0]) < abs(day - nearest[0]):
nearest = rate
if nearest is None:
return None
else:
return (Decimal(nearest[1]), Decimal(nearest[2]))
def __add(self, rates):
"""Saves new rate info."""
data = []
for date, currencies in rates.items():
for currency, rates in currencies.items():
data.append((
util.get_day(date),
currency, str(rates[0]), str(rates[1])
))
self._db.executemany("INSERT INTO rates VALUES (?, ?, ?, ?)", data)
self._db.commit()
