def satoshi_to_currency(num, currency):
"""Converts a given number of satoshi to another currency as a formatted
string rounded down to the proper number of decimal places.
:param num: The number of satoshi.
:type num: ``int``
:param currency: One of the :ref:`supported currencies`.
:type currency: ``str``
:rtype: ``str``
"""
return '{:f}'.format(
Decimal(num / Decimal(EXCHANGE_RATES[currency]())).quantize(
Decimal('0.' + '0' * CURRENCY_PRECISION[currency]),
rounding=ROUND_DOWN).normalize())
def currency_to_satoshi(cls, currency):
headers = {"x-accept-version": "2.0.0",
"Accept": "application/json"}
r = requests.get(cls.SINGLE_RATE % currency, headers=headers)
r.raise_for_status()
rate = r.json()['freecash'][currency]
return int(ONE / Decimal(rate) * FCH)
def satoshi_to_currency_cached(num, currency):
"""Converts a given number of satoshi to another currency as a formatted
string rounded down to the proper number of decimal places. Results are
cached using a decorator for 60 seconds by default. See :ref:`cache times`.
:param num: The number of satoshi.
:type num: ``int``
:param currency: One of the :ref:`supported currencies`.
:type currency: ``str``
:rtype: ``str``
"""
return '{:f}'.format(
Decimal(num /
Decimal(currency_to_satoshi_cached(1, currency))).quantize(
Decimal('0.' + '0' * CURRENCY_PRECISION[currency]),
rounding=ROUND_DOWN).normalize())
def wrapper(amount, currency):
now = time()
cached_rate = cached_rates[currency]
if not cached_rate.satoshis or now - cached_rate.last_update > DEFAULT_CACHE_TIME:
cached_rate.satoshis = EXCHANGE_RATES[currency]()
cached_rate.last_update = now
return int(cached_rate.satoshis * Decimal(amount))
def currency_to_satoshi(amount, currency):
"""Converts a given amount of currency to the equivalent number of
satoshi. The amount can be either an int, float, or string as long as
it is a valid input to :py:class:`decimal.Decimal`.
:param amount: The quantity of currency.
:param currency: One of the :ref:`supported currencies`.
:type currency: ``str``
:rtype: ``int``
"""
satoshis = EXCHANGE_RATES[currency]()
return int(satoshis * Decimal(amount))
from collections import OrderedDict
from decimal import ROUND_DOWN
from functools import wraps
from time import time
import requests
from freetx.utils import Decimal
DEFAULT_CACHE_TIME = 300
# Constant for use in deriving exchange
# rates when given in terms of 1 BCH.
ONE = Decimal(1)
# https://en.bitcoin.it/wiki/Units
SATOSHI = 1
C = 100
FCH = 10 ** 8
SUPPORTED_CURRENCIES = OrderedDict([
('satoshi', 'Satoshi'),
('c', 'cash'),
('fch', 'freecash'),
('usd', 'United States Dollar'),
('eur', 'Eurozone Euro'),
('gbp', 'Pound Sterling'),
('jpy', 'Japanese Yen'),
('cny', 'Chinese Yuan'),
('cad', 'Canadian Dollar'),
('aud', 'Australian Dollar'),
def test_decimal():
assert Decimal(0.8) == Decimal('0.8')
def test_zero_places(self):
assert Decimal(satoshi_to_currency(100000, 'jpy')).as_tuple().exponent == 0